[ { "sku": "232-710B", "brand": "NTN", "manufacturer_designation": "NTN 232/710B", "series": "23200-series", "type": "spherical_roller", "d_mm": 710, "D_mm": 1280, "B_mm": 450, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 18100, "static_load_kN": 32500, "fatigue_load_limit_kN": 1200, "limiting_speed_rpm": 200, "max_rpm": 200, "speed_oil_rpm": 260, "weight_g": 2540000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "232/710B belongs to the 23200 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. Reading the full code: the number gives the 710×1280 mm envelope, — names the cage/capacity execution, no bore suffix means cylindrical bore for a direct shaft seat, and plain outer ring (no D1/W33 groove) completes the order number. The plain outer ring (no D1/W33 groove) makes relubrication part of the design: fresh grease reaches the rolling elements through the outer-ring feature rather than relying solely on end-side packing. Selection: the C0/C ratio of 1.80 (32500/18100 kN) reflects the heavy static and shock proportioning of 232/710B; size the equivalent load at the required L10 with shock factor for the application. Never mount 232/710B by striking the outer ring through the roller set; drive through ring faces (or the adapter sleeve nut) and support the ring square to avoid brinelling the 1280 mm race.", "applications": [ "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "roller-end smearing during skidding starts under light load and high viscosity grease", "brinelling from static overload or a hammer blow during sleeve mounting", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range" ], "pitfalls": [ "At 710 mm bore 232/710B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 200 r/min grease rating is lost to abrasive wear long before fatigue.", "Minimum load must be maintained even at rest under vibration: an unloaded 232/710B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Minimum load must be maintained even at rest under vibration: an unloaded 232/710B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 710 mm bearing, and drive-up procedures differ.", "The 18100/32500 kN ratings, 1200 kN Pu and 2540000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 232/710B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 232/710B?", "a": "232/710B is an NTN double-row spherical roller bearing to ISO 15: 710 mm bore, 1280 mm OD and 450 mm width (27.953 × 50.394 × 17.717 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 18100 kN, C0 32500 kN, Pu 1200 kN, grease limiting speed 200 r/min, oil 260 r/min, mass about 2540000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "232/710B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 232/710BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 232/710B is the basic execution." }, { "q": "What do D1 and W33 mean on 232/710B?", "a": "232/710B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 232/710B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23200 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 18100 kN C / 32500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "232-710BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23200-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 232-710BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "232-710b", "232-710B" ], "locale_variants": {} }, { "sku": "232-710BK", "brand": "NTN", "manufacturer_designation": "NTN 232/710BK", "series": "23200-series", "type": "spherical_roller", "d_mm": 710, "D_mm": 1280, "B_mm": 450, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 18100, "static_load_kN": 32500, "fatigue_load_limit_kN": 1200, "limiting_speed_rpm": 200, "max_rpm": 200, "speed_oil_rpm": 260, "weight_g": 2470000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "232/710BK belongs to the 23200 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. Numbering ties 232/710BK to its envelope and execution: same-number EA versus EM or plain variants share the 710 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Open by design, 232/710BK requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. Selection: the C0/C ratio of 1.80 (32500/18100 kN) reflects the heavy static and shock proportioning of 232/710BK; size the equivalent load at the required L10 with shock factor for the application. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "roller-end smearing during skidding starts under light load and high viscosity grease", "hard-particle indentation through the open arrangement in dusty mining duty", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 710 mm bore 232/710BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 710 mm bearing, and drive-up procedures differ.", "Do not confuse EA and EM at the same number: 232/710BK carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 710×1280 mm envelope is identical.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 18100 kN rating no longer applies.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 18100 kN rating no longer applies.", "The 18100/32500 kN ratings, 1200 kN Pu and 2470000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 232/710BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 232/710BK?", "a": "232/710BK is an NTN double-row spherical roller bearing to ISO 15: 710 mm bore, 1280 mm OD and 450 mm width (27.953 × 50.394 × 17.717 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 18100 kN, C0 32500 kN, Pu 1200 kN, grease limiting speed 200 r/min, oil 260 r/min, mass about 2470000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 232/710BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 232/710B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 232/710BK is the basic execution." }, { "q": "What do D1 and W33 mean on 232/710BK?", "a": "232/710BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 232/710BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23200 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 18100 kN C / 32500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "232-710B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23200-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 232-710B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "232-710bk", "232-710BK" ], "locale_variants": {} }, { "sku": "239-750", "brand": "NTN", "manufacturer_designation": "NTN 239/750", "series": "23900-series", "type": "spherical_roller", "d_mm": 750, "D_mm": 1000, "B_mm": 185, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 5600, "static_load_kN": 13000, "fatigue_load_limit_kN": 990, "limiting_speed_rpm": 260, "max_rpm": 260, "speed_oil_rpm": 340, "weight_g": 412000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, 239/750 denotes the 750 mm bore spherical roller bearing (5600 kN C / 13000 kN C0) in the 23900 series, the self-aligning choice for heavy combined load. On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (cylindrical), lubrication feature (none); 239/750 is assembled exactly in that order. Open by design, 239/750 requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. Selection: the C0/C ratio of 2.32 (13000/5600 kN) reflects the heavy static and shock proportioning of 239/750; size the equivalent load at the required L10 with shock factor for the application. Fillet radii on shaft and housing must clear the ring chamfers of the 185 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.", "applications": [ "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "hard-particle indentation through the open arrangement in dusty mining duty", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient" ], "pitfalls": [ "At 750 mm bore 239/750 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The cylindrical-bore 239/750 and its tapered-bore counterpart 239/750K share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.", "The cylindrical-bore 239/750 and its tapered-bore counterpart 239/750K share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 260 r/min grease rating is lost to abrasive wear long before fatigue.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 5600 kN rating no longer applies.", "The 5600/13000 kN ratings, 990 kN Pu and 412000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/750 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/750?", "a": "239/750 is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1000 mm OD and 185 mm width (29.528 × 39.37 × 7.283 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 5600 kN, C0 13000 kN, Pu 990 kN, grease limiting speed 260 r/min, oil 340 r/min, mass about 412000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/750 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/750K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/750 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/750?", "a": "239/750 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/750 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 5600 kN C / 13000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-750K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-750K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-750" ], "locale_variants": {} }, { "sku": "239-750K", "brand": "NTN", "manufacturer_designation": "NTN 239/750K", "series": "23900-series", "type": "spherical_roller", "d_mm": 750, "D_mm": 1000, "B_mm": 185, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 5600, "static_load_kN": 13000, "fatigue_load_limit_kN": 990, "limiting_speed_rpm": 260, "max_rpm": 260, "speed_oil_rpm": 340, "weight_g": 399000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The NTN order number 239/750K identifies a 750×1000×185 mm (29.528 × 39.37 × 7.283 in) spherical roller bearing, 1:12 tapered bore (K), to the ISO 15 boundary plan. Numbering ties 239/750K to its envelope and execution: same-number EA versus EM or plain variants share the 750 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. The 125.0 mm radial section over the 750 mm bore carries two roller rows; capacity per millimetre of bore is about 7.5 kN/mm, among the highest of rolling bearings for the ISO 15 envelope. Selection: the C0/C ratio of 2.32 (13000/5600 kN) reflects the heavy static and shock proportioning of 239/750K; size the equivalent load at the required L10 with shock factor for the application. Fillet radii on shaft and housing must clear the ring chamfers of the 185 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.", "applications": [ "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "water-induced pitting in washdown or outdoor duty without effective external seals", "hard-particle indentation through the open arrangement in dusty mining duty" ], "pitfalls": [ "At 750 mm bore 239/750K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 750 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "Oil relubrication toward 340 r/min needs drain and level design; flooding the 185 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "The 1:12 tapered bore is the only difference from the cylindrical-bore 239/750: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "The 1:12 tapered bore is the only difference from the cylindrical-bore 239/750: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "The 5600/13000 kN ratings, 990 kN Pu and 399000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/750K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/750K?", "a": "239/750K is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1000 mm OD and 185 mm width (29.528 × 39.37 × 7.283 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 5600 kN, C0 13000 kN, Pu 990 kN, grease limiting speed 260 r/min, oil 340 r/min, mass about 399000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/750K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/750." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/750K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/750K?", "a": "239/750K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/750K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 5600 kN C / 13000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-750", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-750 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-750k", "239-750K" ], "locale_variants": {} }, { "sku": "230-750B", "brand": "NTN", "manufacturer_designation": "NTN 230/750B", "series": "23000-series", "type": "spherical_roller", "d_mm": 750, "D_mm": 1090, "B_mm": 250, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 9100, "static_load_kN": 18300, "fatigue_load_limit_kN": 1290, "limiting_speed_rpm": 250, "max_rpm": 250, "speed_oil_rpm": 320, "weight_g": 790000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NTN lists 230/750B with a cylindrical bore and plain outer ring (no D1/W33 groove): 750 mm bore, 1090 mm OD, 250 mm width, rated 250 r/min on grease. Numbering ties 230/750B to its envelope and execution: same-number EA versus EM or plain variants share the 750 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. The plain outer ring (no D1/W33 groove) makes relubrication part of the design: fresh grease reaches the rolling elements through the outer-ring feature rather than relying solely on end-side packing. With about 12.1 kN of C per millimetre of the 750 mm bore, 230/750B screens interchange candidates quickly — then verify cage (EA/EM), bore (K/K30) and lubrication feature (D1/W33) suffixes. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 750 mm bore assembly by hand to distribute it across both rows.", "applications": [ "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "roller-end smearing during skidding starts under light load and high viscosity grease", "false brinelling on stopped machines exposed to screen or crusher vibration", "water-induced pitting in washdown or outdoor duty without effective external seals" ], "pitfalls": [ "At 750 mm bore 230/750B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Do not confuse EA and EM at the same number: 230/750B carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 750×1090 mm envelope is identical.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 9100 kN rating no longer applies.", "Never substitute 230/750B by envelope alone: the 18300 kN C0 and 1290 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 750 mm bearing, and drive-up procedures differ.", "The 9100/18300 kN ratings, 1290 kN Pu and 790000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/750B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/750B?", "a": "230/750B is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1090 mm OD and 250 mm width (29.528 × 42.913 × 9.843 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 9100 kN, C0 18300 kN, Pu 1290 kN, grease limiting speed 250 r/min, oil 320 r/min, mass about 790000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "230/750B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 230/750BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/750B is the basic execution." }, { "q": "What do D1 and W33 mean on 230/750B?", "a": "230/750B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/750B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 9100 kN C / 18300 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-750BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 230-750BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-750b", "230-750B" ], "locale_variants": {} }, { "sku": "230-750BK", "brand": "NTN", "manufacturer_designation": "NTN 230/750BK", "series": "23000-series", "type": "spherical_roller", "d_mm": 750, "D_mm": 1090, "B_mm": 250, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 9100, "static_load_kN": 18300, "fatigue_load_limit_kN": 1290, "limiting_speed_rpm": 250, "max_rpm": 250, "speed_oil_rpm": 320, "weight_g": 763000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "230/750BK is the basic execution of NTN's spherical roller range for a 750 mm shaft — 9100 kN basic dynamic capacity in a 763000 g, open ISO 15 envelope. The leading digits are the ISO 15 dimension series (23000 series); the bore code resolves to 750 mm (two-digit code ×5, with the 00–03 exception table), and 1090 mm OD / 250 mm width follow the general plan. NTN prints two speeds for 230/750BK: 250 r/min grease and 320 r/min oil — the gap of 70 r/min reflects oil cooling of the heavy roller set. With about 12.1 kN of C per millimetre of the 750 mm bore, 230/750BK screens interchange candidates quickly — then verify cage (EA/EM), bore (K/K30) and lubrication feature (D1/W33) suffixes. Mount 230/750BK on its adapter or withdrawal sleeve on the 750 mm plain shaft: oil the sleeve, fit the lock nut, drive up to the NTN-specified residual clearance (or use oil injection on large seats), then lock the tab washer.", "applications": [ "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "roller-end smearing during skidding starts under light load and high viscosity grease", "rolling-contact fatigue after the catalogue L10 life at the actual load", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient" ], "pitfalls": [ "At 750 mm bore 230/750BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The 1:12 tapered bore is the only difference from the cylindrical-bore 230/750B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 750 mm bearing, and drive-up procedures differ.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 230/750BK in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Oil relubrication toward 320 r/min needs drain and level design; flooding the 250 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "The 9100/18300 kN ratings, 1290 kN Pu and 763000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/750BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/750BK?", "a": "230/750BK is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1090 mm OD and 250 mm width (29.528 × 42.913 × 9.843 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 9100 kN, C0 18300 kN, Pu 1290 kN, grease limiting speed 250 r/min, oil 320 r/min, mass about 763000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 230/750BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 230/750B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/750BK is the basic execution." }, { "q": "What do D1 and W33 mean on 230/750BK?", "a": "230/750BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/750BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 9100 kN C / 18300 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-750B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 230-750B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-750bk", "230-750BK" ], "locale_variants": {} }, { "sku": "240-750B", "brand": "NTN", "manufacturer_designation": "NTN 240/750B", "series": "24000-series", "type": "spherical_roller", "d_mm": 750, "D_mm": 1090, "B_mm": 335, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 11300, "static_load_kN": 24600, "fatigue_load_limit_kN": 1230, "limiting_speed_rpm": 220, "max_rpm": 220, "speed_oil_rpm": 280, "weight_g": 1060000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "240/750B is the basic execution of NTN's spherical roller range for a 750 mm shaft — 11300 kN basic dynamic capacity in a 1060000 g, open ISO 15 envelope. Digit by digit the code reads as spherical-roller dimension series plus 750 mm bore; the 335 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. NTN prints two speeds for 240/750B: 220 r/min grease and 280 r/min oil — the gap of 60 r/min reflects oil cooling of the heavy roller set. Grease/oil ratio: the 220 r/min limiting value is .79 of the 280 r/min oil value; heavy 335 mm-wide cages run hot in churning grease, so quantity and groove supply both matter. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 750 mm bore assembly by hand to distribute it across both rows.", "applications": [ "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 750 mm bore 240/750B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 335 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 220 r/min grease rating is lost to abrasive wear long before fatigue.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 220 r/min grease rating is lost to abrasive wear long before fatigue.", "Oil relubrication toward 280 r/min needs drain and level design; flooding the 335 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "The 11300/24600 kN ratings, 1230 kN Pu and 1060000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/750B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/750B?", "a": "240/750B is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1090 mm OD and 335 mm width (29.528 × 42.913 × 13.189 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 11300 kN, C0 24600 kN, Pu 1230 kN, grease limiting speed 220 r/min, oil 280 r/min, mass about 1060000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "240/750B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 240/750BK30 (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/750B is the basic execution." }, { "q": "What do D1 and W33 mean on 240/750B?", "a": "240/750B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/750B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 11300 kN C / 24600 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-750BK30", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 240-750BK30 (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-750b", "240-750B" ], "locale_variants": {} }, { "sku": "240-750BK30", "brand": "NTN", "manufacturer_designation": "NTN 240/750BK30", "series": "24000-series", "type": "spherical_roller", "d_mm": 750, "D_mm": 1090, "B_mm": 335, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 11300, "static_load_kN": 24600, "fatigue_load_limit_kN": 1230, "limiting_speed_rpm": 220, "max_rpm": 220, "speed_oil_rpm": 280, "weight_g": 1040000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "240/750BK30 is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 750×1090×335 mm to ISO 15, with pressed-steel cage (standard execution). Numbering ties 240/750BK30 to its envelope and execution: same-number EA versus EM or plain variants share the 750 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. NTN prints two speeds for 240/750BK30: 220 r/min grease and 280 r/min oil — the gap of 60 r/min reflects oil cooling of the heavy roller set. Selection: the C0/C ratio of 2.18 (24600/11300 kN) reflects the heavy static and shock proportioning of 240/750BK30; size the equivalent load at the required L10 with shock factor for the application. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "brinelling from static overload or a hammer blow during sleeve mounting", "water-induced pitting in washdown or outdoor duty without effective external seals" ], "pitfalls": [ "At 750 mm bore 240/750BK30 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 220 r/min grease rating is lost to abrasive wear long before fatigue.", "The 1:30 tapered bore is the only difference from the cylindrical-bore 240/750B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 335 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Oil relubrication toward 280 r/min needs drain and level design; flooding the 335 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "The 11300/24600 kN ratings, 1230 kN Pu and 1040000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/750BK30 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/750BK30?", "a": "240/750BK30 is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1090 mm OD and 335 mm width (29.528 × 42.913 × 13.189 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 11300 kN, C0 24600 kN, Pu 1230 kN, grease limiting speed 220 r/min, oil 280 r/min, mass about 1040000 g. It is open, with pressed-steel cage (standard execution) and a 1:30 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K30 denotes a 1:30 tapered bore (the wide 24000 series). 240/750BK30 mounts on a matching adapter or withdrawal sleeve on a plain 750 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 240/750B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/750BK30 is the basic execution." }, { "q": "What do D1 and W33 mean on 240/750BK30?", "a": "240/750BK30 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/750BK30 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 11300 kN C / 24600 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-750B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 240-750B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-750bk30", "240-750BK30" ], "locale_variants": {} }, { "sku": "231-750B", "brand": "NTN", "manufacturer_designation": "NTN 231/750B", "series": "23100-series", "type": "spherical_roller", "d_mm": 750, "D_mm": 1220, "B_mm": 365, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 14300, "static_load_kN": 27200, "fatigue_load_limit_kN": 1130, "limiting_speed_rpm": 200, "max_rpm": 200, "speed_oil_rpm": 260, "weight_g": 1700000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NTN lists 231/750B with a cylindrical bore and plain outer ring (no D1/W33 groove): 750 mm bore, 1220 mm OD, 365 mm width, rated 200 r/min on grease. Reading the full code: the number gives the 750×1220 mm envelope, — names the cage/capacity execution, no bore suffix means cylindrical bore for a direct shaft seat, and plain outer ring (no D1/W33 groove) completes the order number. The bearing accepts predominantly radial load with a moderate axial share, but is not a pure thrust bearing: sustained axial-only load skids the unloaded row and damages the basic cage. 750 mm bore is 29.528 in and 1220 mm OD is 48.031 in; the ISO 15 envelope swaps between brands, but the 14300/27200 kN ratings and cage design are NTN 2203E values. Fit the cylindrical-bore 231/750B with the inner ring heated (max 120 °C) for the shaft interference; the outer ring slides into the housing with its spherical seat able to pivot after seating.", "applications": [ "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient", "hard-particle indentation through the open arrangement in dusty mining duty" ], "pitfalls": [ "At 750 mm bore 231/750B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 365 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Never substitute 231/750B by envelope alone: the 27200 kN C0 and 1130 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 750 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "Never substitute 231/750B by envelope alone: the 27200 kN C0 and 1130 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "The 14300/27200 kN ratings, 1130 kN Pu and 1700000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 231/750B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 231/750B?", "a": "231/750B is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1220 mm OD and 365 mm width (29.528 × 48.031 × 14.37 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 14300 kN, C0 27200 kN, Pu 1130 kN, grease limiting speed 200 r/min, oil 260 r/min, mass about 1700000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "231/750B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 231/750BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 231/750B is the basic execution." }, { "q": "What do D1 and W33 mean on 231/750B?", "a": "231/750B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 231/750B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 14300 kN C / 27200 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "231-750BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23100-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 231-750BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "231-750b", "231-750B" ], "locale_variants": {} }, { "sku": "231-750BK", "brand": "NTN", "manufacturer_designation": "NTN 231/750BK", "series": "23100-series", "type": "spherical_roller", "d_mm": 750, "D_mm": 1220, "B_mm": 365, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 14300, "static_load_kN": 27200, "fatigue_load_limit_kN": 1130, "limiting_speed_rpm": 200, "max_rpm": 200, "speed_oil_rpm": 260, "weight_g": 1650000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For heavy radial load with misalignment on a 750 mm shaft, NTN supplies 231/750BK: sphered outer raceway, two roller rows, pressed-steel cage (standard execution), oil speed 260 r/min. Reading the full code: the number gives the 750×1220 mm envelope, — names the cage/capacity execution, K marks the 1:12 tapered bore for adapter/withdrawal-sleeve mounting, and plain outer ring (no D1/W33 groove) completes the order number. The plain outer ring (no D1/W33 groove) makes relubrication part of the design: fresh grease reaches the rolling elements through the outer-ring feature rather than relying solely on end-side packing. 750 mm bore is 29.528 in and 1220 mm OD is 48.031 in; the ISO 15 envelope swaps between brands, but the 14300/27200 kN ratings and cage design are NTN 2203E values. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 750 mm set.", "applications": [ "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "brinelling from static overload or a hammer blow during sleeve mounting", "water-induced pitting in washdown or outdoor duty without effective external seals" ], "pitfalls": [ "At 750 mm bore 231/750BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 200 r/min grease rating is lost to abrasive wear long before fatigue.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 14300 kN rating no longer applies.", "Never substitute 231/750BK by envelope alone: the 27200 kN C0 and 1130 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 750 mm bearing, and drive-up procedures differ.", "The 14300/27200 kN ratings, 1130 kN Pu and 1650000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 231/750BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 231/750BK?", "a": "231/750BK is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1220 mm OD and 365 mm width (29.528 × 48.031 × 14.37 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 14300 kN, C0 27200 kN, Pu 1130 kN, grease limiting speed 200 r/min, oil 260 r/min, mass about 1650000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 231/750BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 231/750B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 231/750BK is the basic execution." }, { "q": "What do D1 and W33 mean on 231/750BK?", "a": "231/750BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 231/750BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 14300 kN C / 27200 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "231-750B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23100-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 231-750B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "231-750bk", "231-750BK" ], "locale_variants": {} }, { "sku": "232-750B", "brand": "NTN", "manufacturer_designation": "NTN 232/750B", "series": "23200-series", "type": "spherical_roller", "d_mm": 750, "D_mm": 1360, "B_mm": 475, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 20300, "static_load_kN": 36500, "fatigue_load_limit_kN": 1980, "limiting_speed_rpm": 180, "max_rpm": 180, "speed_oil_rpm": 240, "weight_g": 3050000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NTN lists 232/750B with a cylindrical bore and plain outer ring (no D1/W33 groove): 750 mm bore, 1360 mm OD, 475 mm width, rated 180 r/min on grease. Numbering ties 232/750B to its envelope and execution: same-number EA versus EM or plain variants share the 750 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Pu 1980 kN is the catalogue fatigue load limit for 232/750B, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. Catalogue mass 3050000 g (3050.00 kg) for the 750×1360×475 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 750 mm bore assembly by hand to distribute it across both rows.", "applications": [ "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "roller-end smearing during skidding starts under light load and high viscosity grease", "false brinelling on stopped machines exposed to screen or crusher vibration", "rolling-contact fatigue after the catalogue L10 life at the actual load" ], "pitfalls": [ "At 750 mm bore 232/750B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Minimum load must be maintained even at rest under vibration: an unloaded 232/750B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 180 r/min grease rating is lost to abrasive wear long before fatigue.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 232/750B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 232/750B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The 20300/36500 kN ratings, 1980 kN Pu and 3050000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 232/750B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 232/750B?", "a": "232/750B is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1360 mm OD and 475 mm width (29.528 × 53.543 × 18.701 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 20300 kN, C0 36500 kN, Pu 1980 kN, grease limiting speed 180 r/min, oil 240 r/min, mass about 3050000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "232/750B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 232/750BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 232/750B is the basic execution." }, { "q": "What do D1 and W33 mean on 232/750B?", "a": "232/750B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 232/750B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23200 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 20300 kN C / 36500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "232-750BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23200-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 232-750BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "232-750b", "232-750B" ], "locale_variants": {} }, { "sku": "232-750BK", "brand": "NTN", "manufacturer_designation": "NTN 232/750BK", "series": "23200-series", "type": "spherical_roller", "d_mm": 750, "D_mm": 1360, "B_mm": 475, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 20300, "static_load_kN": 36500, "fatigue_load_limit_kN": 1980, "limiting_speed_rpm": 180, "max_rpm": 180, "speed_oil_rpm": 240, "weight_g": 2960000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The NTN order number 232/750BK identifies a 750×1360×475 mm (29.528 × 53.543 × 18.701 in) spherical roller bearing, 1:12 tapered bore (K), to the ISO 15 boundary plan. Numbering ties 232/750BK to its envelope and execution: same-number EA versus EM or plain variants share the 750 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. NTN prints two speeds for 232/750BK: 180 r/min grease and 240 r/min oil — the gap of 60 r/min reflects oil cooling of the heavy roller set. Equivalent-load planning keeps a radial plus moderate axial combination on 232/750BK; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 750 mm set.", "applications": [ "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "false brinelling on stopped machines exposed to screen or crusher vibration", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 750 mm bore 232/750BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Do not confuse EA and EM at the same number: 232/750BK carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 750×1360 mm envelope is identical.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 180 r/min grease rating is lost to abrasive wear long before fatigue.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 180 r/min grease rating is lost to abrasive wear long before fatigue.", "Oil relubrication toward 240 r/min needs drain and level design; flooding the 475 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "The 20300/36500 kN ratings, 1980 kN Pu and 2960000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 232/750BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 232/750BK?", "a": "232/750BK is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1360 mm OD and 475 mm width (29.528 × 53.543 × 18.701 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 20300 kN, C0 36500 kN, Pu 1980 kN, grease limiting speed 180 r/min, oil 240 r/min, mass about 2960000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 232/750BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 232/750B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 232/750BK is the basic execution." }, { "q": "What do D1 and W33 mean on 232/750BK?", "a": "232/750BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 232/750BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23200 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 20300 kN C / 36500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "232-750B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23200-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 232-750B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "232-750bk", "232-750BK" ], "locale_variants": {} }, { "sku": "239-800", "brand": "NTN", "manufacturer_designation": "NTN 239/800", "series": "23900-series", "type": "spherical_roller", "d_mm": 800, "D_mm": 1060, "B_mm": 195, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 6000, "static_load_kN": 13700, "fatigue_load_limit_kN": 1040, "limiting_speed_rpm": 240, "max_rpm": 240, "speed_oil_rpm": 310, "weight_g": 487000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NTN lists 239/800 with a cylindrical bore and plain outer ring (no D1/W33 groove): 800 mm bore, 1060 mm OD, 195 mm width, rated 240 r/min on grease. The leading digits are the ISO 15 dimension series (23900 series); the bore code resolves to 800 mm (two-digit code ×5, with the 00–03 exception table), and 1060 mm OD / 195 mm width follow the general plan. The bearing accepts predominantly radial load with a moderate axial share, but is not a pure thrust bearing: sustained axial-only load skids the unloaded row and damages the basic cage. Equivalent-load planning keeps a radial plus moderate axial combination on 239/800; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. Fit the cylindrical-bore 239/800 with the inner ring heated (max 120 °C) for the shaft interference; the outer ring slides into the housing with its spherical seat able to pivot after seating.", "applications": [ "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient", "rolling-contact fatigue after the catalogue L10 life at the actual load" ], "pitfalls": [ "At 800 mm bore 239/800 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 239/800 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 239/800 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 800 mm bearing, and drive-up procedures differ.", "Never substitute 239/800 by envelope alone: the 13700 kN C0 and 1040 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "The 6000/13700 kN ratings, 1040 kN Pu and 487000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/800 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/800?", "a": "239/800 is an NTN double-row spherical roller bearing to ISO 15: 800 mm bore, 1060 mm OD and 195 mm width (31.496 × 41.732 × 7.677 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 6000 kN, C0 13700 kN, Pu 1040 kN, grease limiting speed 240 r/min, oil 310 r/min, mass about 487000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/800 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/800K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/800 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/800?", "a": "239/800 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/800 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 6000 kN C / 13700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-800K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-800K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-800" ], "locale_variants": {} }, { "sku": "239-800K", "brand": "NTN", "manufacturer_designation": "NTN 239/800K", "series": "23900-series", "type": "spherical_roller", "d_mm": 800, "D_mm": 1060, "B_mm": 195, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 6000, "static_load_kN": 13700, "fatigue_load_limit_kN": 1040, "limiting_speed_rpm": 240, "max_rpm": 240, "speed_oil_rpm": 310, "weight_g": 471000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "239/800K is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 800×1060×195 mm to ISO 15, with pressed-steel cage (standard execution). Numbering ties 239/800K to its envelope and execution: same-number EA versus EM or plain variants share the 800 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Suffix reading on 239/800K: the bare number is the standard open execution; K marks the 1:12 tapered bore; quote the full code because each suffix is a distinct article. With about 7.5 kN of C per millimetre of the 800 mm bore, 239/800K screens interchange candidates quickly — then verify cage (EA/EM), bore (K/K30) and lubrication feature (D1/W33) suffixes. On vibrating-duty shafts verify the radial clearance class and cage choice at order time; the open 239/800K leaves sealing and the C3/C4 clearance decision to the application drawing.", "applications": [ "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient", "water-induced pitting in washdown or outdoor duty without effective external seals" ], "pitfalls": [ "At 800 mm bore 239/800K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 800 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "Never substitute 239/800K by envelope alone: the 13700 kN C0 and 1040 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 800 mm bearing, and drive-up procedures differ.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 195 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The 6000/13700 kN ratings, 1040 kN Pu and 471000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/800K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/800K?", "a": "239/800K is an NTN double-row spherical roller bearing to ISO 15: 800 mm bore, 1060 mm OD and 195 mm width (31.496 × 41.732 × 7.677 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 6000 kN, C0 13700 kN, Pu 1040 kN, grease limiting speed 240 r/min, oil 310 r/min, mass about 471000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/800K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/800." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/800K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/800K?", "a": "239/800K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/800K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 6000 kN C / 13700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-800", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-800 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-800k", "239-800K" ], "locale_variants": {} }, { "sku": "230-800B", "brand": "NTN", "manufacturer_designation": "NTN 230/800B", "series": "23000-series", "type": "spherical_roller", "d_mm": 800, "D_mm": 1150, "B_mm": 258, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 9350, "static_load_kN": 19500, "fatigue_load_limit_kN": 1340, "limiting_speed_rpm": 220, "max_rpm": 220, "speed_oil_rpm": 290, "weight_g": 890000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For heavy radial load with misalignment on a 800 mm shaft, NTN supplies 230/800B: sphered outer raceway, two roller rows, pressed-steel cage (standard execution), oil speed 290 r/min. The leading digits are the ISO 15 dimension series (23000 series); the bore code resolves to 800 mm (two-digit code ×5, with the 00–03 exception table), and 1150 mm OD / 258 mm width follow the general plan. Pu 1340 kN is the catalogue fatigue load limit for 230/800B, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. Pu 1340 kN against C0 19500 kN anchors the contamination derating; for dirty mining duty the adjusted life of 230/800B moves with cleanliness far more than with small C variations. On vibrating-duty shafts verify the radial clearance class and cage choice at order time; the open 230/800B leaves sealing and the C3/C4 clearance decision to the application drawing.", "applications": [ "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "false brinelling on stopped machines exposed to screen or crusher vibration", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient" ], "pitfalls": [ "At 800 mm bore 230/800B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 220 r/min grease rating is lost to abrasive wear long before fatigue.", "Oil relubrication toward 290 r/min needs drain and level design; flooding the 258 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 220 r/min grease rating is lost to abrasive wear long before fatigue.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 230/800B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The 9350/19500 kN ratings, 1340 kN Pu and 890000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/800B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/800B?", "a": "230/800B is an NTN double-row spherical roller bearing to ISO 15: 800 mm bore, 1150 mm OD and 258 mm width (31.496 × 45.276 × 10.157 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 9350 kN, C0 19500 kN, Pu 1340 kN, grease limiting speed 220 r/min, oil 290 r/min, mass about 890000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "230/800B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 230/800BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/800B is the basic execution." }, { "q": "What do D1 and W33 mean on 230/800B?", "a": "230/800B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/800B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 9350 kN C / 19500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-800BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 230-800BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-800b", "230-800B" ], "locale_variants": {} }, { "sku": "230-800BK", "brand": "NTN", "manufacturer_designation": "NTN 230/800BK", "series": "23000-series", "type": "spherical_roller", "d_mm": 800, "D_mm": 1150, "B_mm": 258, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 9350, "static_load_kN": 19500, "fatigue_load_limit_kN": 1340, "limiting_speed_rpm": 220, "max_rpm": 220, "speed_oil_rpm": 290, "weight_g": 859000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "230/800BK is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 800×1150×258 mm to ISO 15, with pressed-steel cage (standard execution). Reading the full code: the number gives the 800×1150 mm envelope, — names the cage/capacity execution, K marks the 1:12 tapered bore for adapter/withdrawal-sleeve mounting, and plain outer ring (no D1/W33 groove) completes the order number. Pu 1340 kN is the catalogue fatigue load limit for 230/800BK, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. Pu 1340 kN against C0 19500 kN anchors the contamination derating; for dirty mining duty the adjusted life of 230/800BK moves with cleanliness far more than with small C variations. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 800 mm bore assembly by hand to distribute it across both rows.", "applications": [ "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "roller-end smearing during skidding starts under light load and high viscosity grease", "hard-particle indentation through the open arrangement in dusty mining duty", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 800 mm bore 230/800BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Never substitute 230/800BK by envelope alone: the 19500 kN C0 and 1340 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 258 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Do not confuse EA and EM at the same number: 230/800BK carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 800×1150 mm envelope is identical.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 230/800BK in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The 9350/19500 kN ratings, 1340 kN Pu and 859000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/800BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/800BK?", "a": "230/800BK is an NTN double-row spherical roller bearing to ISO 15: 800 mm bore, 1150 mm OD and 258 mm width (31.496 × 45.276 × 10.157 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 9350 kN, C0 19500 kN, Pu 1340 kN, grease limiting speed 220 r/min, oil 290 r/min, mass about 859000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 230/800BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 230/800B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/800BK is the basic execution." }, { "q": "What do D1 and W33 mean on 230/800BK?", "a": "230/800BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/800BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 9350 kN C / 19500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-800B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 230-800B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-800bk", "230-800BK" ], "locale_variants": {} }, { "sku": "240-800B", "brand": "NTN", "manufacturer_designation": "NTN 240/800B", "series": "24000-series", "type": "spherical_roller", "d_mm": 800, "D_mm": 1150, "B_mm": 345, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 12400, "static_load_kN": 27800, "fatigue_load_limit_kN": 1360, "limiting_speed_rpm": 200, "max_rpm": 200, "speed_oil_rpm": 260, "weight_g": 1190000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "240/800B is the basic execution of NTN's spherical roller range for a 800 mm shaft — 12400 kN basic dynamic capacity in a 1190000 g, open ISO 15 envelope. Reading the full code: the number gives the 800×1150 mm envelope, — names the cage/capacity execution, no bore suffix means cylindrical bore for a direct shaft seat, and plain outer ring (no D1/W33 groove) completes the order number. Suffix reading on 240/800B: the bare number is the standard open execution; B marks the standard large-bore internal design on slash-size 230–232 series; quote the full code because each suffix is a distinct article. With about 15.5 kN of C per millimetre of the 800 mm bore, 240/800B screens interchange candidates quickly — then verify cage (EA/EM), bore (K/K30) and lubrication feature (D1/W33) suffixes. Never mount 240/800B by striking the outer ring through the roller set; drive through ring faces (or the adapter sleeve nut) and support the ring square to avoid brinelling the 1150 mm race.", "applications": [ "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "roller-end smearing during skidding starts under light load and high viscosity grease", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range" ], "pitfalls": [ "At 800 mm bore 240/800B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Do not confuse EA and EM at the same number: 240/800B carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 800×1150 mm envelope is identical.", "Minimum load must be maintained even at rest under vibration: an unloaded 240/800B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 345 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 345 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The 12400/27800 kN ratings, 1360 kN Pu and 1190000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/800B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/800B?", "a": "240/800B is an NTN double-row spherical roller bearing to ISO 15: 800 mm bore, 1150 mm OD and 345 mm width (31.496 × 45.276 × 13.583 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 12400 kN, C0 27800 kN, Pu 1360 kN, grease limiting speed 200 r/min, oil 260 r/min, mass about 1190000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "240/800B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 240/800BK30 (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/800B is the basic execution." }, { "q": "What do D1 and W33 mean on 240/800B?", "a": "240/800B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/800B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 12400 kN C / 27800 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-800BK30", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 240-800BK30 (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-800b", "240-800B" ], "locale_variants": {} }, { "sku": "240-800BK30", "brand": "NTN", "manufacturer_designation": "NTN 240/800BK30", "series": "24000-series", "type": "spherical_roller", "d_mm": 800, "D_mm": 1150, "B_mm": 345, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 12400, "static_load_kN": 27800, "fatigue_load_limit_kN": 1360, "limiting_speed_rpm": 200, "max_rpm": 200, "speed_oil_rpm": 260, "weight_g": 1170000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "240/800BK30 is the basic execution of NTN's spherical roller range for a 800 mm shaft — 12400 kN basic dynamic capacity in a 1170000 g, open ISO 15 envelope. On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (K30), lubrication feature (none); 240/800BK30 is assembled exactly in that order. The 175.0 mm radial section over the 800 mm bore carries two roller rows; capacity per millimetre of bore is about 15.5 kN/mm, among the highest of rolling bearings for the ISO 15 envelope. With about 15.5 kN of C per millimetre of the 800 mm bore, 240/800BK30 screens interchange candidates quickly — then verify cage (EA/EM), bore (K/K30) and lubrication feature (D1/W33) suffixes. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 800 mm bore assembly by hand to distribute it across both rows.", "applications": [ "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range", "brinelling from static overload or a hammer blow during sleeve mounting" ], "pitfalls": [ "At 800 mm bore 240/800BK30 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 240/800BK30 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Do not confuse EA and EM at the same number: 240/800BK30 carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 800×1150 mm envelope is identical.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 345 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The 1:30 tapered bore is the only difference from the cylindrical-bore 240/800B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "The 12400/27800 kN ratings, 1360 kN Pu and 1170000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/800BK30 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/800BK30?", "a": "240/800BK30 is an NTN double-row spherical roller bearing to ISO 15: 800 mm bore, 1150 mm OD and 345 mm width (31.496 × 45.276 × 13.583 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 12400 kN, C0 27800 kN, Pu 1360 kN, grease limiting speed 200 r/min, oil 260 r/min, mass about 1170000 g. It is open, with pressed-steel cage (standard execution) and a 1:30 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K30 denotes a 1:30 tapered bore (the wide 24000 series). 240/800BK30 mounts on a matching adapter or withdrawal sleeve on a plain 800 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 240/800B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/800BK30 is the basic execution." }, { "q": "What do D1 and W33 mean on 240/800BK30?", "a": "240/800BK30 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/800BK30 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 12400 kN C / 27800 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-800B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 240-800B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-800bk30", "240-800BK30" ], "locale_variants": {} }, { "sku": "231-800B", "brand": "NTN", "manufacturer_designation": "NTN 231/800B", "series": "23100-series", "type": "spherical_roller", "d_mm": 800, "D_mm": 1280, "B_mm": 375, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 16000, "static_load_kN": 31000, "fatigue_load_limit_kN": 1780, "limiting_speed_rpm": 180, "max_rpm": 180, "speed_oil_rpm": 240, "weight_g": 1890000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NTN lists 231/800B with a cylindrical bore and plain outer ring (no D1/W33 groove): 800 mm bore, 1280 mm OD, 375 mm width, rated 180 r/min on grease. Reading the full code: the number gives the 800×1280 mm envelope, — names the cage/capacity execution, no bore suffix means cylindrical bore for a direct shaft seat, and plain outer ring (no D1/W33 groove) completes the order number. The sphered outer raceway lets the inner-ring assembly pivot, accommodating shaft deflection and housing misalignment (around 1–2° for this class; use the 2203E value for the exact series) without edge loading the rollers. Selection: the C0/C ratio of 1.94 (31000/16000 kN) reflects the heavy static and shock proportioning of 231/800B; size the equivalent load at the required L10 with shock factor for the application. Fillet radii on shaft and housing must clear the ring chamfers of the 375 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.", "applications": [ "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "cage damage when a mounting force is applied through the roller set instead of the ring face", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "brinelling from static overload or a hammer blow during sleeve mounting", "water-induced pitting in washdown or outdoor duty without effective external seals" ], "pitfalls": [ "At 800 mm bore 231/800B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 375 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 375 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The cylindrical-bore 231/800B and its tapered-bore counterpart 231/800BK share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.", "Minimum load must be maintained even at rest under vibration: an unloaded 231/800B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The 16000/31000 kN ratings, 1780 kN Pu and 1890000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 231/800B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 231/800B?", "a": "231/800B is an NTN double-row spherical roller bearing to ISO 15: 800 mm bore, 1280 mm OD and 375 mm width (31.496 × 50.394 × 14.764 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 16000 kN, C0 31000 kN, Pu 1780 kN, grease limiting speed 180 r/min, oil 240 r/min, mass about 1890000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "231/800B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 231/800BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 231/800B is the basic execution." }, { "q": "What do D1 and W33 mean on 231/800B?", "a": "231/800B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 231/800B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 16000 kN C / 31000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "231-800BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23100-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 231-800BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "231-800b", "231-800B" ], "locale_variants": {} }, { "sku": "231-800BK", "brand": "NTN", "manufacturer_designation": "NTN 231/800BK", "series": "23100-series", "type": "spherical_roller", "d_mm": 800, "D_mm": 1280, "B_mm": 375, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 16000, "static_load_kN": 31000, "fatigue_load_limit_kN": 1780, "limiting_speed_rpm": 180, "max_rpm": 180, "speed_oil_rpm": 240, "weight_g": 1830000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, 231/800BK denotes the 800 mm bore spherical roller bearing (16000 kN C / 31000 kN C0) in the 23100 series, the self-aligning choice for heavy combined load. Numbering ties 231/800BK to its envelope and execution: same-number EA versus EM or plain variants share the 800 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. At 16000 kN C and 1830000 g mass the 23100 series part is built for shock and vibration; the 375 mm-wide ring needs square abutments to keep both rows equally loaded. Catalogue mass 1830000 g (1830.00 kg) for the 800×1280×375 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "cage damage when a mounting force is applied through the roller set instead of the ring face", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "false brinelling on stopped machines exposed to screen or crusher vibration", "brinelling from static overload or a hammer blow during sleeve mounting" ], "pitfalls": [ "At 800 mm bore 231/800BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The 1:12 tapered bore is the only difference from the cylindrical-bore 231/800B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 800 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 231/800BK in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 180 r/min grease rating is lost to abrasive wear long before fatigue.", "The 16000/31000 kN ratings, 1780 kN Pu and 1830000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 231/800BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 231/800BK?", "a": "231/800BK is an NTN double-row spherical roller bearing to ISO 15: 800 mm bore, 1280 mm OD and 375 mm width (31.496 × 50.394 × 14.764 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 16000 kN, C0 31000 kN, Pu 1780 kN, grease limiting speed 180 r/min, oil 240 r/min, mass about 1830000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 231/800BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 231/800B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 231/800BK is the basic execution." }, { "q": "What do D1 and W33 mean on 231/800BK?", "a": "231/800BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 231/800BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 16000 kN C / 31000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "231-800B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23100-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 231-800B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "231-800bk", "231-800BK" ], "locale_variants": {} }, { "sku": "239-850", "brand": "NTN", "manufacturer_designation": "NTN 239/850", "series": "23900-series", "type": "spherical_roller", "d_mm": 850, "D_mm": 1120, "B_mm": 200, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 6500, "static_load_kN": 15100, "fatigue_load_limit_kN": 1080, "limiting_speed_rpm": 220, "max_rpm": 220, "speed_oil_rpm": 290, "weight_g": 550000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "239/850 is the basic execution of NTN's spherical roller range for a 850 mm shaft — 6500 kN basic dynamic capacity in a 550000 g, open ISO 15 envelope. The leading digits are the ISO 15 dimension series (23900 series); the bore code resolves to 850 mm (two-digit code ×5, with the 00–03 exception table), and 1120 mm OD / 200 mm width follow the general plan. Two symmetric roller rows share the load: C 6500 kN, C0 15100 kN (C0/C ≈ 2.32), with useful axial capacity in either direction alongside the dominant radial load. Catalogue mass 550000 g (550.00 kg) for the 850×1120×200 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 850 mm bore assembly by hand to distribute it across both rows.", "applications": [ "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "roller-end smearing during skidding starts under light load and high viscosity grease", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range", "water-induced pitting in washdown or outdoor duty without effective external seals" ], "pitfalls": [ "At 850 mm bore 239/850 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Oil relubrication toward 290 r/min needs drain and level design; flooding the 200 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 6500 kN rating no longer applies.", "Minimum load must be maintained even at rest under vibration: an unloaded 239/850 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 850 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "The 6500/15100 kN ratings, 1080 kN Pu and 550000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/850 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/850?", "a": "239/850 is an NTN double-row spherical roller bearing to ISO 15: 850 mm bore, 1120 mm OD and 200 mm width (33.465 × 44.094 × 7.874 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 6500 kN, C0 15100 kN, Pu 1080 kN, grease limiting speed 220 r/min, oil 290 r/min, mass about 550000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/850 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/850K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/850 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/850?", "a": "239/850 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/850 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 6500 kN C / 15100 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-850K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-850K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-850" ], "locale_variants": {} }, { "sku": "239-850K", "brand": "NTN", "manufacturer_designation": "NTN 239/850K", "series": "23900-series", "type": "spherical_roller", "d_mm": 850, "D_mm": 1120, "B_mm": 200, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 6500, "static_load_kN": 15100, "fatigue_load_limit_kN": 1080, "limiting_speed_rpm": 220, "max_rpm": 220, "speed_oil_rpm": 290, "weight_g": 532000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "239/850K is the basic execution of NTN's spherical roller range for a 850 mm shaft — 6500 kN basic dynamic capacity in a 532000 g, open ISO 15 envelope. On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (K), lubrication feature (none); 239/850K is assembled exactly in that order. Pu 1080 kN is the catalogue fatigue load limit for 239/850K, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. Pu 1080 kN against C0 15100 kN anchors the contamination derating; for dirty mining duty the adjusted life of 239/850K moves with cleanliness far more than with small C variations. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 850 mm bore assembly by hand to distribute it across both rows.", "applications": [ "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient" ], "pitfalls": [ "At 850 mm bore 239/850K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Oil relubrication toward 290 r/min needs drain and level design; flooding the 200 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 239/850K in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 850 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 239/850K in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The 6500/15100 kN ratings, 1080 kN Pu and 532000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/850K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/850K?", "a": "239/850K is an NTN double-row spherical roller bearing to ISO 15: 850 mm bore, 1120 mm OD and 200 mm width (33.465 × 44.094 × 7.874 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 6500 kN, C0 15100 kN, Pu 1080 kN, grease limiting speed 220 r/min, oil 290 r/min, mass about 532000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/850K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/850." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/850K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/850K?", "a": "239/850K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/850K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 6500 kN C / 15100 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-850", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-850 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-850k", "239-850K" ], "locale_variants": {} }, { "sku": "230-850B", "brand": "NTN", "manufacturer_designation": "NTN 230/850B", "series": "23000-series", "type": "spherical_roller", "d_mm": 850, "D_mm": 1220, "B_mm": 272, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 10900, "static_load_kN": 22700, "fatigue_load_limit_kN": 1510, "limiting_speed_rpm": 210, "max_rpm": 210, "speed_oil_rpm": 270, "weight_g": 1050000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "230/850B is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 850×1220×272 mm to ISO 15, with pressed-steel cage (standard execution). On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (cylindrical), lubrication feature (none); 230/850B is assembled exactly in that order. NTN prints two speeds for 230/850B: 210 r/min grease and 270 r/min oil — the gap of 60 r/min reflects oil cooling of the heavy roller set. Equivalent-load planning keeps a radial plus moderate axial combination on 230/850B; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 850 mm bore assembly by hand to distribute it across both rows.", "applications": [ "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "hard-particle indentation through the open arrangement in dusty mining duty", "brinelling from static overload or a hammer blow during sleeve mounting" ], "pitfalls": [ "At 850 mm bore 230/850B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 850 mm bearing, and drive-up procedures differ.", "Minimum load must be maintained even at rest under vibration: an unloaded 230/850B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 850 mm bearing, and drive-up procedures differ.", "Oil relubrication toward 270 r/min needs drain and level design; flooding the 272 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "The 10900/22700 kN ratings, 1510 kN Pu and 1050000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/850B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/850B?", "a": "230/850B is an NTN double-row spherical roller bearing to ISO 15: 850 mm bore, 1220 mm OD and 272 mm width (33.465 × 48.031 × 10.709 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 10900 kN, C0 22700 kN, Pu 1510 kN, grease limiting speed 210 r/min, oil 270 r/min, mass about 1050000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "230/850B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 230/850BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/850B is the basic execution." }, { "q": "What do D1 and W33 mean on 230/850B?", "a": "230/850B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/850B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 10900 kN C / 22700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-850BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 230-850BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-850b", "230-850B" ], "locale_variants": {} }, { "sku": "230-850BK", "brand": "NTN", "manufacturer_designation": "NTN 230/850BK", "series": "23000-series", "type": "spherical_roller", "d_mm": 850, "D_mm": 1220, "B_mm": 272, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 10900, "static_load_kN": 22700, "fatigue_load_limit_kN": 1510, "limiting_speed_rpm": 210, "max_rpm": 210, "speed_oil_rpm": 270, "weight_g": 1010000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For heavy radial load with misalignment on a 850 mm shaft, NTN supplies 230/850BK: sphered outer raceway, two roller rows, pressed-steel cage (standard execution), oil speed 270 r/min. Digit by digit the code reads as spherical-roller dimension series plus 850 mm bore; the 272 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. At 10900 kN C and 1010000 g mass the 23000 series part is built for shock and vibration; the 272 mm-wide ring needs square abutments to keep both rows equally loaded. Catalogue mass 1010000 g (1010.00 kg) for the 850×1220×272 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. Mount 230/850BK on its adapter or withdrawal sleeve on the 850 mm plain shaft: oil the sleeve, fit the lock nut, drive up to the NTN-specified residual clearance (or use oil injection on large seats), then lock the tab washer.", "applications": [ "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "hard-particle indentation through the open arrangement in dusty mining duty", "rolling-contact fatigue after the catalogue L10 life at the actual load" ], "pitfalls": [ "At 850 mm bore 230/850BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Never substitute 230/850BK by envelope alone: the 22700 kN C0 and 1510 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "Never substitute 230/850BK by envelope alone: the 22700 kN C0 and 1510 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "The 1:12 tapered bore is the only difference from the cylindrical-bore 230/850B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 210 r/min grease rating is lost to abrasive wear long before fatigue.", "The 10900/22700 kN ratings, 1510 kN Pu and 1010000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/850BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/850BK?", "a": "230/850BK is an NTN double-row spherical roller bearing to ISO 15: 850 mm bore, 1220 mm OD and 272 mm width (33.465 × 48.031 × 10.709 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 10900 kN, C0 22700 kN, Pu 1510 kN, grease limiting speed 210 r/min, oil 270 r/min, mass about 1010000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 230/850BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 230/850B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/850BK is the basic execution." }, { "q": "What do D1 and W33 mean on 230/850BK?", "a": "230/850BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/850BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 10900 kN C / 22700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-850B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 230-850B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-850bk", "230-850BK" ], "locale_variants": {} }, { "sku": "240-850B", "brand": "NTN", "manufacturer_designation": "NTN 240/850B", "series": "24000-series", "type": "spherical_roller", "d_mm": 850, "D_mm": 1220, "B_mm": 365, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 13900, "static_load_kN": 31500, "fatigue_load_limit_kN": 1490, "limiting_speed_rpm": 180, "max_rpm": 180, "speed_oil_rpm": 240, "weight_g": 1410000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, 240/850B denotes the 850 mm bore spherical roller bearing (13900 kN C / 31500 kN C0) in the 24000 series, the self-aligning choice for heavy combined load. The leading digits are the ISO 15 dimension series (24000 series); the bore code resolves to 850 mm (two-digit code ×5, with the 00–03 exception table), and 1220 mm OD / 365 mm width follow the general plan. The plain outer ring (no D1/W33 groove) makes relubrication part of the design: fresh grease reaches the rolling elements through the outer-ring feature rather than relying solely on end-side packing. The 185.0 mm section height hosts the spherical roller geometry; shaft and housing fillet radii must clear the chamfer table so the 365 mm-wide ring seats fully on both sides. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "false brinelling on stopped machines exposed to screen or crusher vibration", "hard-particle indentation through the open arrangement in dusty mining duty" ], "pitfalls": [ "At 850 mm bore 240/850B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Minimum load must be maintained even at rest under vibration: an unloaded 240/850B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Oil relubrication toward 240 r/min needs drain and level design; flooding the 365 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 13900 kN rating no longer applies.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 850 mm bearing, and drive-up procedures differ.", "The 13900/31500 kN ratings, 1490 kN Pu and 1410000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/850B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/850B?", "a": "240/850B is an NTN double-row spherical roller bearing to ISO 15: 850 mm bore, 1220 mm OD and 365 mm width (33.465 × 48.031 × 14.37 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 13900 kN, C0 31500 kN, Pu 1490 kN, grease limiting speed 180 r/min, oil 240 r/min, mass about 1410000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "240/850B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 240/850BK30 (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/850B is the basic execution." }, { "q": "What do D1 and W33 mean on 240/850B?", "a": "240/850B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/850B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 13900 kN C / 31500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-850BK30", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 240-850BK30 (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-850b", "240-850B" ], "locale_variants": {} }, { "sku": "240-850BK30", "brand": "NTN", "manufacturer_designation": "NTN 240/850BK30", "series": "24000-series", "type": "spherical_roller", "d_mm": 850, "D_mm": 1220, "B_mm": 365, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 13900, "static_load_kN": 31500, "fatigue_load_limit_kN": 1490, "limiting_speed_rpm": 180, "max_rpm": 180, "speed_oil_rpm": 240, "weight_g": 1390000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, 240/850BK30 denotes the 850 mm bore spherical roller bearing (13900 kN C / 31500 kN C0) in the 24000 series, the self-aligning choice for heavy combined load. Digit by digit the code reads as spherical-roller dimension series plus 850 mm bore; the 365 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. Suffix reading on 240/850BK30: the bare number is the standard open execution; K30 marks the 1:30 tapered bore of the wide series; B marks the standard large-bore internal design on slash-size 230–232 series; quote the full code because each suffix is a distinct article. Pu 1490 kN against C0 31500 kN anchors the contamination derating; for dirty mining duty the adjusted life of 240/850BK30 moves with cleanliness far more than with small C variations. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "false brinelling on stopped machines exposed to screen or crusher vibration", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 850 mm bore 240/850BK30 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Do not confuse EA and EM at the same number: 240/850BK30 carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 850×1220 mm envelope is identical.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 850 mm bearing, and drive-up procedures differ.", "Minimum load must be maintained even at rest under vibration: an unloaded 240/850BK30 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 365 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The 13900/31500 kN ratings, 1490 kN Pu and 1390000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/850BK30 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/850BK30?", "a": "240/850BK30 is an NTN double-row spherical roller bearing to ISO 15: 850 mm bore, 1220 mm OD and 365 mm width (33.465 × 48.031 × 14.37 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 13900 kN, C0 31500 kN, Pu 1490 kN, grease limiting speed 180 r/min, oil 240 r/min, mass about 1390000 g. It is open, with pressed-steel cage (standard execution) and a 1:30 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K30 denotes a 1:30 tapered bore (the wide 24000 series). 240/850BK30 mounts on a matching adapter or withdrawal sleeve on a plain 850 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 240/850B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/850BK30 is the basic execution." }, { "q": "What do D1 and W33 mean on 240/850BK30?", "a": "240/850BK30 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/850BK30 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 13900 kN C / 31500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-850B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 240-850B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-850bk30", "240-850BK30" ], "locale_variants": {} }, { "sku": "231-850B", "brand": "NTN", "manufacturer_designation": "NTN 231/850B", "series": "23100-series", "type": "spherical_roller", "d_mm": 850, "D_mm": 1360, "B_mm": 400, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 17300, "static_load_kN": 34000, "fatigue_load_limit_kN": 1380, "limiting_speed_rpm": 170, "max_rpm": 170, "speed_oil_rpm": 220, "weight_g": 2270000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "231/850B is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 850×1360×400 mm to ISO 15, with pressed-steel cage (standard execution). Digit by digit the code reads as spherical-roller dimension series plus 850 mm bore; the 400 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. The sphered outer raceway lets the inner-ring assembly pivot, accommodating shaft deflection and housing misalignment (around 1–2° for this class; use the 2203E value for the exact series) without edge loading the rollers. Equivalent-load planning keeps a radial plus moderate axial combination on 231/850B; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 850 mm set.", "applications": [ "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "water-induced pitting in washdown or outdoor duty without effective external seals", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient" ], "pitfalls": [ "At 850 mm bore 231/850B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Minimum load must be maintained even at rest under vibration: an unloaded 231/850B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 850 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 400 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Minimum load must be maintained even at rest under vibration: an unloaded 231/850B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The 17300/34000 kN ratings, 1380 kN Pu and 2270000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 231/850B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 231/850B?", "a": "231/850B is an NTN double-row spherical roller bearing to ISO 15: 850 mm bore, 1360 mm OD and 400 mm width (33.465 × 53.543 × 15.748 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 17300 kN, C0 34000 kN, Pu 1380 kN, grease limiting speed 170 r/min, oil 220 r/min, mass about 2270000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "231/850B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 231/850BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 231/850B is the basic execution." }, { "q": "What do D1 and W33 mean on 231/850B?", "a": "231/850B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 231/850B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 17300 kN C / 34000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "231-850BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23100-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 231-850BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "231-850b", "231-850B" ], "locale_variants": {} }, { "sku": "231-850BK", "brand": "NTN", "manufacturer_designation": "NTN 231/850BK", "series": "23100-series", "type": "spherical_roller", "d_mm": 850, "D_mm": 1360, "B_mm": 400, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 17300, "static_load_kN": 34000, "fatigue_load_limit_kN": 1380, "limiting_speed_rpm": 170, "max_rpm": 170, "speed_oil_rpm": 220, "weight_g": 2200000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The NTN order number 231/850BK identifies a 850×1360×400 mm (33.465 × 53.543 × 15.748 in) spherical roller bearing, 1:12 tapered bore (K), to the ISO 15 boundary plan. Numbering ties 231/850BK to its envelope and execution: same-number EA versus EM or plain variants share the 850 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Two symmetric roller rows share the load: C 17300 kN, C0 34000 kN (C0/C ≈ 1.97), with useful axial capacity in either direction alongside the dominant radial load. Grease/oil ratio: the 170 r/min limiting value is .77 of the 220 r/min oil value; heavy 400 mm-wide cages run hot in churning grease, so quantity and groove supply both matter. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 850 mm set.", "applications": [ "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "false brinelling on stopped machines exposed to screen or crusher vibration", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range" ], "pitfalls": [ "At 850 mm bore 231/850BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Never substitute 231/850BK by envelope alone: the 34000 kN C0 and 1380 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 400 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 850 mm bearing, and drive-up procedures differ.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 850 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "The 17300/34000 kN ratings, 1380 kN Pu and 2200000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 231/850BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 231/850BK?", "a": "231/850BK is an NTN double-row spherical roller bearing to ISO 15: 850 mm bore, 1360 mm OD and 400 mm width (33.465 × 53.543 × 15.748 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 17300 kN, C0 34000 kN, Pu 1380 kN, grease limiting speed 170 r/min, oil 220 r/min, mass about 2200000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 231/850BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 231/850B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 231/850BK is the basic execution." }, { "q": "What do D1 and W33 mean on 231/850BK?", "a": "231/850BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 231/850BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 17300 kN C / 34000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "231-850B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23100-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 231-850B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "231-850bk", "231-850BK" ], "locale_variants": {} }, { "sku": "239-900", "brand": "NTN", "manufacturer_designation": "NTN 239/900", "series": "23900-series", "type": "spherical_roller", "d_mm": 900, "D_mm": 1180, "B_mm": 206, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 7400, "static_load_kN": 17300, "fatigue_load_limit_kN": 1230, "limiting_speed_rpm": 210, "max_rpm": 210, "speed_oil_rpm": 270, "weight_g": 623000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For heavy radial load with misalignment on a 900 mm shaft, NTN supplies 239/900: sphered outer raceway, two roller rows, pressed-steel cage (standard execution), oil speed 270 r/min. Reading the full code: the number gives the 900×1180 mm envelope, — names the cage/capacity execution, no bore suffix means cylindrical bore for a direct shaft seat, and plain outer ring (no D1/W33 groove) completes the order number. Open by design, 239/900 requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. Pu 1230 kN against C0 17300 kN anchors the contamination derating; for dirty mining duty the adjusted life of 239/900 moves with cleanliness far more than with small C variations. Fit the cylindrical-bore 239/900 with the inner ring heated (max 120 °C) for the shaft interference; the outer ring slides into the housing with its spherical seat able to pivot after seating.", "applications": [ "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "hard-particle indentation through the open arrangement in dusty mining duty", "water-induced pitting in washdown or outdoor duty without effective external seals" ], "pitfalls": [ "At 900 mm bore 239/900 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 900 mm bearing, and drive-up procedures differ.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 206 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 239/900 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 7400 kN rating no longer applies.", "The 7400/17300 kN ratings, 1230 kN Pu and 623000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/900 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/900?", "a": "239/900 is an NTN double-row spherical roller bearing to ISO 15: 900 mm bore, 1180 mm OD and 206 mm width (35.433 × 46.457 × 8.11 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 7400 kN, C0 17300 kN, Pu 1230 kN, grease limiting speed 210 r/min, oil 270 r/min, mass about 623000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/900 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/900K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/900 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/900?", "a": "239/900 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/900 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 7400 kN C / 17300 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-900K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-900K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-900" ], "locale_variants": {} }, { "sku": "239-900K", "brand": "NTN", "manufacturer_designation": "NTN 239/900K", "series": "23900-series", "type": "spherical_roller", "d_mm": 900, "D_mm": 1180, "B_mm": 206, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 7400, "static_load_kN": 17300, "fatigue_load_limit_kN": 1230, "limiting_speed_rpm": 210, "max_rpm": 210, "speed_oil_rpm": 270, "weight_g": 603000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The NTN order number 239/900K identifies a 900×1180×206 mm (35.433 × 46.457 × 8.11 in) spherical roller bearing, 1:12 tapered bore (K), to the ISO 15 boundary plan. On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (K), lubrication feature (none); 239/900K is assembled exactly in that order. Open by design, 239/900K requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. Equivalent-load planning keeps a radial plus moderate axial combination on 239/900K; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. On vibrating-duty shafts verify the radial clearance class and cage choice at order time; the open 239/900K leaves sealing and the C3/C4 clearance decision to the application drawing.", "applications": [ "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range", "brinelling from static overload or a hammer blow during sleeve mounting" ], "pitfalls": [ "At 900 mm bore 239/900K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Oil relubrication toward 270 r/min needs drain and level design; flooding the 206 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 900 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "Oil relubrication toward 270 r/min needs drain and level design; flooding the 206 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 7400 kN rating no longer applies.", "The 7400/17300 kN ratings, 1230 kN Pu and 603000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/900K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/900K?", "a": "239/900K is an NTN double-row spherical roller bearing to ISO 15: 900 mm bore, 1180 mm OD and 206 mm width (35.433 × 46.457 × 8.11 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 7400 kN, C0 17300 kN, Pu 1230 kN, grease limiting speed 210 r/min, oil 270 r/min, mass about 603000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/900K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/900." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/900K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/900K?", "a": "239/900K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/900K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 7400 kN C / 17300 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-900", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-900 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-900k", "239-900K" ], "locale_variants": {} }, { "sku": "230-900B", "brand": "NTN", "manufacturer_designation": "NTN 230/900B", "series": "23000-series", "type": "spherical_roller", "d_mm": 900, "D_mm": 1280, "B_mm": 280, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 11400, "static_load_kN": 24700, "fatigue_load_limit_kN": 1580, "limiting_speed_rpm": 190, "max_rpm": 190, "speed_oil_rpm": 250, "weight_g": 1170000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NTN lists 230/900B with a cylindrical bore and plain outer ring (no D1/W33 groove): 900 mm bore, 1280 mm OD, 280 mm width, rated 190 r/min on grease. Numbering ties 230/900B to its envelope and execution: same-number EA versus EM or plain variants share the 900 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. At 11400 kN C and 1170000 g mass the 23000 series part is built for shock and vibration; the 280 mm-wide ring needs square abutments to keep both rows equally loaded. With about 12.7 kN of C per millimetre of the 900 mm bore, 230/900B screens interchange candidates quickly — then verify cage (EA/EM), bore (K/K30) and lubrication feature (D1/W33) suffixes. Fillet radii on shaft and housing must clear the ring chamfers of the 280 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.", "applications": [ "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "roller-end smearing during skidding starts under light load and high viscosity grease", "brinelling from static overload or a hammer blow during sleeve mounting", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range" ], "pitfalls": [ "At 900 mm bore 230/900B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 280 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 230/900B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 11400 kN rating no longer applies.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 190 r/min grease rating is lost to abrasive wear long before fatigue.", "The 11400/24700 kN ratings, 1580 kN Pu and 1170000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/900B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/900B?", "a": "230/900B is an NTN double-row spherical roller bearing to ISO 15: 900 mm bore, 1280 mm OD and 280 mm width (35.433 × 50.394 × 11.024 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 11400 kN, C0 24700 kN, Pu 1580 kN, grease limiting speed 190 r/min, oil 250 r/min, mass about 1170000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "230/900B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 230/900BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/900B is the basic execution." }, { "q": "What do D1 and W33 mean on 230/900B?", "a": "230/900B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/900B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 11400 kN C / 24700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-900BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 230-900BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-900b", "230-900B" ], "locale_variants": {} }, { "sku": "230-900BK", "brand": "NTN", "manufacturer_designation": "NTN 230/900BK", "series": "23000-series", "type": "spherical_roller", "d_mm": 900, "D_mm": 1280, "B_mm": 280, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 11400, "static_load_kN": 24700, "fatigue_load_limit_kN": 1580, "limiting_speed_rpm": 190, "max_rpm": 190, "speed_oil_rpm": 250, "weight_g": 1130000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, 230/900BK denotes the 900 mm bore spherical roller bearing (11400 kN C / 24700 kN C0) in the 23000 series, the self-aligning choice for heavy combined load. On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (K), lubrication feature (none); 230/900BK is assembled exactly in that order. NTN prints two speeds for 230/900BK: 190 r/min grease and 250 r/min oil — the gap of 60 r/min reflects oil cooling of the heavy roller set. Speed planning: 190 r/min grease limiting speed is the cage/kinematic ceiling and 250 r/min is the oil-lubricated value for the 900 mm bore; vibrating screens rarely approach either and are load/cage limited instead. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 900 mm bore assembly by hand to distribute it across both rows.", "applications": [ "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "roller-end smearing during skidding starts under light load and high viscosity grease", "brinelling from static overload or a hammer blow during sleeve mounting", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range" ], "pitfalls": [ "At 900 mm bore 230/900BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Oil relubrication toward 250 r/min needs drain and level design; flooding the 280 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Oil relubrication toward 250 r/min needs drain and level design; flooding the 280 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 900 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "Oil relubrication toward 250 r/min needs drain and level design; flooding the 280 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "The 11400/24700 kN ratings, 1580 kN Pu and 1130000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/900BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/900BK?", "a": "230/900BK is an NTN double-row spherical roller bearing to ISO 15: 900 mm bore, 1280 mm OD and 280 mm width (35.433 × 50.394 × 11.024 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 11400 kN, C0 24700 kN, Pu 1580 kN, grease limiting speed 190 r/min, oil 250 r/min, mass about 1130000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 230/900BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 230/900B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/900BK is the basic execution." }, { "q": "What do D1 and W33 mean on 230/900BK?", "a": "230/900BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/900BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 11400 kN C / 24700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-900B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 230-900B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-900bk", "230-900BK" ], "locale_variants": {} }, { "sku": "240-900B", "brand": "NTN", "manufacturer_designation": "NTN 240/900B", "series": "24000-series", "type": "spherical_roller", "d_mm": 900, "D_mm": 1280, "B_mm": 375, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 14700, "static_load_kN": 33500, "fatigue_load_limit_kN": 1580, "limiting_speed_rpm": 170, "max_rpm": 170, "speed_oil_rpm": 220, "weight_g": 1570000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, 240/900B denotes the 900 mm bore spherical roller bearing (14700 kN C / 33500 kN C0) in the 24000 series, the self-aligning choice for heavy combined load. Digit by digit the code reads as spherical-roller dimension series plus 900 mm bore; the 375 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. NTN prints two speeds for 240/900B: 170 r/min grease and 220 r/min oil — the gap of 50 r/min reflects oil cooling of the heavy roller set. Grease/oil ratio: the 170 r/min limiting value is .77 of the 220 r/min oil value; heavy 375 mm-wide cages run hot in churning grease, so quantity and groove supply both matter. Fit the cylindrical-bore 240/900B with the inner ring heated (max 120 °C) for the shaft interference; the outer ring slides into the housing with its spherical seat able to pivot after seating.", "applications": [ "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "water-induced pitting in washdown or outdoor duty without effective external seals", "brinelling from static overload or a hammer blow during sleeve mounting" ], "pitfalls": [ "At 900 mm bore 240/900B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 900 mm bearing, and drive-up procedures differ.", "Do not confuse EA and EM at the same number: 240/900B carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 900×1280 mm envelope is identical.", "Never substitute 240/900B by envelope alone: the 33500 kN C0 and 1580 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "Oil relubrication toward 220 r/min needs drain and level design; flooding the 375 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "The 14700/33500 kN ratings, 1580 kN Pu and 1570000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/900B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/900B?", "a": "240/900B is an NTN double-row spherical roller bearing to ISO 15: 900 mm bore, 1280 mm OD and 375 mm width (35.433 × 50.394 × 14.764 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 14700 kN, C0 33500 kN, Pu 1580 kN, grease limiting speed 170 r/min, oil 220 r/min, mass about 1570000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "240/900B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 240/900BK30 (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/900B is the basic execution." }, { "q": "What do D1 and W33 mean on 240/900B?", "a": "240/900B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/900B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 14700 kN C / 33500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-900BK30", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 240-900BK30 (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-900b", "240-900B" ], "locale_variants": {} }, { "sku": "240-900BK30", "brand": "NTN", "manufacturer_designation": "NTN 240/900BK30", "series": "24000-series", "type": "spherical_roller", "d_mm": 900, "D_mm": 1280, "B_mm": 375, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 14700, "static_load_kN": 33500, "fatigue_load_limit_kN": 1580, "limiting_speed_rpm": 170, "max_rpm": 170, "speed_oil_rpm": 220, "weight_g": 1540000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For heavy radial load with misalignment on a 900 mm shaft, NTN supplies 240/900BK30: sphered outer raceway, two roller rows, pressed-steel cage (standard execution), oil speed 220 r/min. Digit by digit the code reads as spherical-roller dimension series plus 900 mm bore; the 375 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. The sphered outer raceway lets the inner-ring assembly pivot, accommodating shaft deflection and housing misalignment (around 1–2° for this class; use the 2203E value for the exact series) without edge loading the rollers. The 190.0 mm section height hosts the spherical roller geometry; shaft and housing fillet radii must clear the chamfer table so the 375 mm-wide ring seats fully on both sides. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 900 mm bore assembly by hand to distribute it across both rows.", "applications": [ "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "roller-end smearing during skidding starts under light load and high viscosity grease", "water-induced pitting in washdown or outdoor duty without effective external seals", "water-induced pitting in washdown or outdoor duty without effective external seals" ], "pitfalls": [ "At 900 mm bore 240/900BK30 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 240/900BK30 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 240/900BK30 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Minimum load must be maintained even at rest under vibration: an unloaded 240/900BK30 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Minimum load must be maintained even at rest under vibration: an unloaded 240/900BK30 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The 14700/33500 kN ratings, 1580 kN Pu and 1540000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/900BK30 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/900BK30?", "a": "240/900BK30 is an NTN double-row spherical roller bearing to ISO 15: 900 mm bore, 1280 mm OD and 375 mm width (35.433 × 50.394 × 14.764 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 14700 kN, C0 33500 kN, Pu 1580 kN, grease limiting speed 170 r/min, oil 220 r/min, mass about 1540000 g. It is open, with pressed-steel cage (standard execution) and a 1:30 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K30 denotes a 1:30 tapered bore (the wide 24000 series). 240/900BK30 mounts on a matching adapter or withdrawal sleeve on a plain 900 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 240/900B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/900BK30 is the basic execution." }, { "q": "What do D1 and W33 mean on 240/900BK30?", "a": "240/900BK30 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/900BK30 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 14700 kN C / 33500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-900B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 240-900B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-900bk30", "240-900BK30" ], "locale_variants": {} }, { "sku": "231-900B", "brand": "NTN", "manufacturer_designation": "NTN 231/900B", "series": "23100-series", "type": "spherical_roller", "d_mm": 900, "D_mm": 1420, "B_mm": 412, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 18700, "static_load_kN": 38000, "fatigue_load_limit_kN": 2030, "limiting_speed_rpm": 150, "max_rpm": 150, "speed_oil_rpm": 200, "weight_g": 2500000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "231/900B is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 900×1420×412 mm to ISO 15, with pressed-steel cage (standard execution). Digit by digit the code reads as spherical-roller dimension series plus 900 mm bore; the 412 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. The bearing accepts predominantly radial load with a moderate axial share, but is not a pure thrust bearing: sustained axial-only load skids the unloaded row and damages the basic cage. Catalogue mass 2500000 g (2500.00 kg) for the 900×1420×412 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. Fillet radii on shaft and housing must clear the ring chamfers of the 412 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.", "applications": [ "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "rolling-contact fatigue after the catalogue L10 life at the actual load", "brinelling from static overload or a hammer blow during sleeve mounting" ], "pitfalls": [ "At 900 mm bore 231/900B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Minimum load must be maintained even at rest under vibration: an unloaded 231/900B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The cylindrical-bore 231/900B and its tapered-bore counterpart 231/900BK share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.", "Minimum load must be maintained even at rest under vibration: an unloaded 231/900B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Never substitute 231/900B by envelope alone: the 38000 kN C0 and 2030 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "The 18700/38000 kN ratings, 2030 kN Pu and 2500000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 231/900B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 231/900B?", "a": "231/900B is an NTN double-row spherical roller bearing to ISO 15: 900 mm bore, 1420 mm OD and 412 mm width (35.433 × 55.906 × 16.22 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 18700 kN, C0 38000 kN, Pu 2030 kN, grease limiting speed 150 r/min, oil 200 r/min, mass about 2500000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "231/900B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 231/900BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 231/900B is the basic execution." }, { "q": "What do D1 and W33 mean on 231/900B?", "a": "231/900B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 231/900B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 18700 kN C / 38000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "231-900BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23100-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 231-900BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "231-900b", "231-900B" ], "locale_variants": {} }, { "sku": "231-900BK", "brand": "NTN", "manufacturer_designation": "NTN 231/900BK", "series": "23100-series", "type": "spherical_roller", "d_mm": 900, "D_mm": 1420, "B_mm": 412, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 18700, "static_load_kN": 38000, "fatigue_load_limit_kN": 2030, "limiting_speed_rpm": 150, "max_rpm": 150, "speed_oil_rpm": 200, "weight_g": 2420000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "231/900BK is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 900×1420×412 mm to ISO 15, with pressed-steel cage (standard execution). The leading digits are the ISO 15 dimension series (23100 series); the bore code resolves to 900 mm (two-digit code ×5, with the 00–03 exception table), and 1420 mm OD / 412 mm width follow the general plan. Two symmetric roller rows share the load: C 18700 kN, C0 38000 kN (C0/C ≈ 2.03), with useful axial capacity in either direction alongside the dominant radial load. Pu 2030 kN against C0 38000 kN anchors the contamination derating; for dirty mining duty the adjusted life of 231/900BK moves with cleanliness far more than with small C variations. On vibrating-duty shafts verify the radial clearance class and cage choice at order time; the open 231/900BK leaves sealing and the C3/C4 clearance decision to the application drawing.", "applications": [ "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 900 mm bore 231/900BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Never substitute 231/900BK by envelope alone: the 38000 kN C0 and 2030 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "Minimum load must be maintained even at rest under vibration: an unloaded 231/900BK on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The 1:12 tapered bore is the only difference from the cylindrical-bore 231/900B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 900 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "The 18700/38000 kN ratings, 2030 kN Pu and 2420000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 231/900BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 231/900BK?", "a": "231/900BK is an NTN double-row spherical roller bearing to ISO 15: 900 mm bore, 1420 mm OD and 412 mm width (35.433 × 55.906 × 16.22 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 18700 kN, C0 38000 kN, Pu 2030 kN, grease limiting speed 150 r/min, oil 200 r/min, mass about 2420000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 231/900BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 231/900B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 231/900BK is the basic execution." }, { "q": "What do D1 and W33 mean on 231/900BK?", "a": "231/900BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 231/900BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 18700 kN C / 38000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "231-900B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23100-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 231-900B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "231-900bk", "231-900BK" ], "locale_variants": {} }, { "sku": "239-950", "brand": "NTN", "manufacturer_designation": "NTN 239/950", "series": "23900-series", "type": "spherical_roller", "d_mm": 950, "D_mm": 1250, "B_mm": 224, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 8650, "static_load_kN": 20500, "fatigue_load_limit_kN": 1390, "limiting_speed_rpm": 190, "max_rpm": 190, "speed_oil_rpm": 250, "weight_g": 774000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The NTN order number 239/950 identifies a 950×1250×224 mm (37.402 × 49.213 × 8.819 in) spherical roller bearing, cylindrical bore, to the ISO 15 boundary plan. Reading the full code: the number gives the 950×1250 mm envelope, — names the cage/capacity execution, no bore suffix means cylindrical bore for a direct shaft seat, and plain outer ring (no D1/W33 groove) completes the order number. The sphered outer raceway lets the inner-ring assembly pivot, accommodating shaft deflection and housing misalignment (around 1–2° for this class; use the 2203E value for the exact series) without edge loading the rollers. Equivalent-load planning keeps a radial plus moderate axial combination on 239/950; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 950 mm bore assembly by hand to distribute it across both rows.", "applications": [ "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 950 mm bore 239/950 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 950 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "Minimum load must be maintained even at rest under vibration: an unloaded 239/950 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 950 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "Minimum load must be maintained even at rest under vibration: an unloaded 239/950 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The 8650/20500 kN ratings, 1390 kN Pu and 774000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/950 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/950?", "a": "239/950 is an NTN double-row spherical roller bearing to ISO 15: 950 mm bore, 1250 mm OD and 224 mm width (37.402 × 49.213 × 8.819 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 8650 kN, C0 20500 kN, Pu 1390 kN, grease limiting speed 190 r/min, oil 250 r/min, mass about 774000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/950 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/950K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/950 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/950?", "a": "239/950 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/950 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 8650 kN C / 20500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-950K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-950K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-950" ], "locale_variants": {} }, { "sku": "239-950K", "brand": "NTN", "manufacturer_designation": "NTN 239/950K", "series": "23900-series", "type": "spherical_roller", "d_mm": 950, "D_mm": 1250, "B_mm": 224, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 8650, "static_load_kN": 20500, "fatigue_load_limit_kN": 1390, "limiting_speed_rpm": 190, "max_rpm": 190, "speed_oil_rpm": 250, "weight_g": 749000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, 239/950K denotes the 950 mm bore spherical roller bearing (8650 kN C / 20500 kN C0) in the 23900 series, the self-aligning choice for heavy combined load. Reading the full code: the number gives the 950×1250 mm envelope, — names the cage/capacity execution, K marks the 1:12 tapered bore for adapter/withdrawal-sleeve mounting, and plain outer ring (no D1/W33 groove) completes the order number. At 8650 kN C and 749000 g mass the 23900 series part is built for shock and vibration; the 224 mm-wide ring needs square abutments to keep both rows equally loaded. With about 9.1 kN of C per millimetre of the 950 mm bore, 239/950K screens interchange candidates quickly — then verify cage (EA/EM), bore (K/K30) and lubrication feature (D1/W33) suffixes. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "false brinelling on stopped machines exposed to screen or crusher vibration", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range" ], "pitfalls": [ "At 950 mm bore 239/950K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The 1:12 tapered bore is the only difference from the cylindrical-bore 239/950: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 224 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 224 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 190 r/min grease rating is lost to abrasive wear long before fatigue.", "The 8650/20500 kN ratings, 1390 kN Pu and 749000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/950K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/950K?", "a": "239/950K is an NTN double-row spherical roller bearing to ISO 15: 950 mm bore, 1250 mm OD and 224 mm width (37.402 × 49.213 × 8.819 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 8650 kN, C0 20500 kN, Pu 1390 kN, grease limiting speed 190 r/min, oil 250 r/min, mass about 749000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/950K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/950." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/950K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/950K?", "a": "239/950K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/950K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 8650 kN C / 20500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-950", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-950 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-950k", "239-950K" ], "locale_variants": {} }, { "sku": "230-950B", "brand": "NTN", "manufacturer_designation": "NTN 230/950B", "series": "23000-series", "type": "spherical_roller", "d_mm": 950, "D_mm": 1360, "B_mm": 300, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 12800, "static_load_kN": 28400, "fatigue_load_limit_kN": 1750, "limiting_speed_rpm": 180, "max_rpm": 180, "speed_oil_rpm": 230, "weight_g": 1430000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The NTN order number 230/950B identifies a 950×1360×300 mm (37.402 × 53.543 × 11.811 in) spherical roller bearing, cylindrical bore, to the ISO 15 boundary plan. Reading the full code: the number gives the 950×1360 mm envelope, — names the cage/capacity execution, no bore suffix means cylindrical bore for a direct shaft seat, and plain outer ring (no D1/W33 groove) completes the order number. The plain outer ring (no D1/W33 groove) makes relubrication part of the design: fresh grease reaches the rolling elements through the outer-ring feature rather than relying solely on end-side packing. Selection: the C0/C ratio of 2.22 (28400/12800 kN) reflects the heavy static and shock proportioning of 230/950B; size the equivalent load at the required L10 with shock factor for the application. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "rolling-contact fatigue after the catalogue L10 life at the actual load", "rolling-contact fatigue after the catalogue L10 life at the actual load" ], "pitfalls": [ "At 950 mm bore 230/950B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 230/950B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Do not confuse EA and EM at the same number: 230/950B carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 950×1360 mm envelope is identical.", "The cylindrical-bore 230/950B and its tapered-bore counterpart 230/950BK share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 950 mm bearing, and drive-up procedures differ.", "The 12800/28400 kN ratings, 1750 kN Pu and 1430000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/950B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/950B?", "a": "230/950B is an NTN double-row spherical roller bearing to ISO 15: 950 mm bore, 1360 mm OD and 300 mm width (37.402 × 53.543 × 11.811 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 12800 kN, C0 28400 kN, Pu 1750 kN, grease limiting speed 180 r/min, oil 230 r/min, mass about 1430000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "230/950B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 230/950BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/950B is the basic execution." }, { "q": "What do D1 and W33 mean on 230/950B?", "a": "230/950B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/950B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 12800 kN C / 28400 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-950BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 230-950BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-950b", "230-950B" ], "locale_variants": {} }, { "sku": "230-950BK", "brand": "NTN", "manufacturer_designation": "NTN 230/950BK", "series": "23000-series", "type": "spherical_roller", "d_mm": 950, "D_mm": 1360, "B_mm": 300, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 12800, "static_load_kN": 28400, "fatigue_load_limit_kN": 1750, "limiting_speed_rpm": 180, "max_rpm": 180, "speed_oil_rpm": 230, "weight_g": 1380000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The NTN order number 230/950BK identifies a 950×1360×300 mm (37.402 × 53.543 × 11.811 in) spherical roller bearing, 1:12 tapered bore (K), to the ISO 15 boundary plan. On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (K), lubrication feature (none); 230/950BK is assembled exactly in that order. The sphered outer raceway lets the inner-ring assembly pivot, accommodating shaft deflection and housing misalignment (around 1–2° for this class; use the 2203E value for the exact series) without edge loading the rollers. Catalogue mass 1380000 g (1380.00 kg) for the 950×1360×300 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 950 mm set.", "applications": [ "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "false brinelling on stopped machines exposed to screen or crusher vibration", "rolling-contact fatigue after the catalogue L10 life at the actual load" ], "pitfalls": [ "At 950 mm bore 230/950BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 12800 kN rating no longer applies.", "Minimum load must be maintained even at rest under vibration: an unloaded 230/950BK on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 950 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "Minimum load must be maintained even at rest under vibration: an unloaded 230/950BK on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The 12800/28400 kN ratings, 1750 kN Pu and 1380000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/950BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/950BK?", "a": "230/950BK is an NTN double-row spherical roller bearing to ISO 15: 950 mm bore, 1360 mm OD and 300 mm width (37.402 × 53.543 × 11.811 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 12800 kN, C0 28400 kN, Pu 1750 kN, grease limiting speed 180 r/min, oil 230 r/min, mass about 1380000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 230/950BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 230/950B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/950BK is the basic execution." }, { "q": "What do D1 and W33 mean on 230/950BK?", "a": "230/950BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/950BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 12800 kN C / 28400 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-950B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 230-950B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-950bk", "230-950BK" ], "locale_variants": {} }, { "sku": "240-950B", "brand": "NTN", "manufacturer_designation": "NTN 240/950B", "series": "24000-series", "type": "spherical_roller", "d_mm": 950, "D_mm": 1360, "B_mm": 412, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 17200, "static_load_kN": 40000, "fatigue_load_limit_kN": 1780, "limiting_speed_rpm": 160, "max_rpm": 160, "speed_oil_rpm": 210, "weight_g": 1970000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "240/950B belongs to the 24000 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. Numbering ties 240/950B to its envelope and execution: same-number EA versus EM or plain variants share the 950 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. NTN prints two speeds for 240/950B: 160 r/min grease and 210 r/min oil — the gap of 50 r/min reflects oil cooling of the heavy roller set. Pu 1780 kN against C0 40000 kN anchors the contamination derating; for dirty mining duty the adjusted life of 240/950B moves with cleanliness far more than with small C variations. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "cage damage when a mounting force is applied through the roller set instead of the ring face", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "hard-particle indentation through the open arrangement in dusty mining duty", "water-induced pitting in washdown or outdoor duty without effective external seals" ], "pitfalls": [ "At 950 mm bore 240/950B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 950 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 240/950B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Do not confuse EA and EM at the same number: 240/950B carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 950×1360 mm envelope is identical.", "Oil relubrication toward 210 r/min needs drain and level design; flooding the 412 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "The 17200/40000 kN ratings, 1780 kN Pu and 1970000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/950B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/950B?", "a": "240/950B is an NTN double-row spherical roller bearing to ISO 15: 950 mm bore, 1360 mm OD and 412 mm width (37.402 × 53.543 × 16.22 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 17200 kN, C0 40000 kN, Pu 1780 kN, grease limiting speed 160 r/min, oil 210 r/min, mass about 1970000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "240/950B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 240/950BK30 (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/950B is the basic execution." }, { "q": "What do D1 and W33 mean on 240/950B?", "a": "240/950B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/950B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 17200 kN C / 40000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-950BK30", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 240-950BK30 (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-950b", "240-950B" ], "locale_variants": {} }, { "sku": "240-950BK30", "brand": "NTN", "manufacturer_designation": "NTN 240/950BK30", "series": "24000-series", "type": "spherical_roller", "d_mm": 950, "D_mm": 1360, "B_mm": 412, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 17200, "static_load_kN": 40000, "fatigue_load_limit_kN": 1780, "limiting_speed_rpm": 160, "max_rpm": 160, "speed_oil_rpm": 210, "weight_g": 1940000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "240/950BK30 is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 950×1360×412 mm to ISO 15, with pressed-steel cage (standard execution). On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (K30), lubrication feature (none); 240/950BK30 is assembled exactly in that order. The 205.0 mm radial section over the 950 mm bore carries two roller rows; capacity per millimetre of bore is about 18.1 kN/mm, among the highest of rolling bearings for the ISO 15 envelope. With about 18.1 kN of C per millimetre of the 950 mm bore, 240/950BK30 screens interchange candidates quickly — then verify cage (EA/EM), bore (K/K30) and lubrication feature (D1/W33) suffixes. On vibrating-duty shafts verify the radial clearance class and cage choice at order time; the open 240/950BK30 leaves sealing and the C3/C4 clearance decision to the application drawing.", "applications": [ "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient", "hard-particle indentation through the open arrangement in dusty mining duty" ], "pitfalls": [ "At 950 mm bore 240/950BK30 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 412 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The 1:30 tapered bore is the only difference from the cylindrical-bore 240/950B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 950 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "The 1:30 tapered bore is the only difference from the cylindrical-bore 240/950B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "The 17200/40000 kN ratings, 1780 kN Pu and 1940000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/950BK30 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/950BK30?", "a": "240/950BK30 is an NTN double-row spherical roller bearing to ISO 15: 950 mm bore, 1360 mm OD and 412 mm width (37.402 × 53.543 × 16.22 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 17200 kN, C0 40000 kN, Pu 1780 kN, grease limiting speed 160 r/min, oil 210 r/min, mass about 1940000 g. It is open, with pressed-steel cage (standard execution) and a 1:30 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K30 denotes a 1:30 tapered bore (the wide 24000 series). 240/950BK30 mounts on a matching adapter or withdrawal sleeve on a plain 950 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 240/950B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/950BK30 is the basic execution." }, { "q": "What do D1 and W33 mean on 240/950BK30?", "a": "240/950BK30 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/950BK30 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 17200 kN C / 40000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-950B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 240-950B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=216", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-950bk30", "240-950BK30" ], "locale_variants": {} }, { "sku": "239-1000", "brand": "NTN", "manufacturer_designation": "NTN 239/1000", "series": "23900-series", "type": "spherical_roller", "d_mm": 1000, "D_mm": 1320, "B_mm": 236, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 9550, "static_load_kN": 22700, "fatigue_load_limit_kN": 1520, "limiting_speed_rpm": 180, "max_rpm": 180, "speed_oil_rpm": 230, "weight_g": 916000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, 239/1000 denotes the 1000 mm bore spherical roller bearing (9550 kN C / 22700 kN C0) in the 23900 series, the self-aligning choice for heavy combined load. The leading digits are the ISO 15 dimension series (23900 series); the bore code resolves to 1000 mm (two-digit code ×5, with the 00–03 exception table), and 1320 mm OD / 236 mm width follow the general plan. Suffix reading on 239/1000: the bare number is the standard open execution; quote the full code because each suffix is a distinct article. Grease/oil ratio: the 180 r/min limiting value is .78 of the 230 r/min oil value; heavy 236 mm-wide cages run hot in churning grease, so quantity and groove supply both matter. Never mount 239/1000 by striking the outer ring through the roller set; drive through ring faces (or the adapter sleeve nut) and support the ring square to avoid brinelling the 1320 mm race.", "applications": [ "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient" ], "pitfalls": [ "At 1000 mm bore 239/1000 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 239/1000 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Never substitute 239/1000 by envelope alone: the 22700 kN C0 and 1520 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1000 mm bearing, and drive-up procedures differ.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 236 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The 9550/22700 kN ratings, 1520 kN Pu and 916000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1000 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1000?", "a": "239/1000 is an NTN double-row spherical roller bearing to ISO 15: 1000 mm bore, 1320 mm OD and 236 mm width (39.37 × 51.969 × 9.291 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 9550 kN, C0 22700 kN, Pu 1520 kN, grease limiting speed 180 r/min, oil 230 r/min, mass about 916000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/1000 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/1000K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1000 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1000?", "a": "239/1000 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1000 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 9550 kN C / 22700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1000K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-1000K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1000" ], "locale_variants": {} }, { "sku": "239-1000K", "brand": "NTN", "manufacturer_designation": "NTN 239/1000K", "series": "23900-series", "type": "spherical_roller", "d_mm": 1000, "D_mm": 1320, "B_mm": 236, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 9550, "static_load_kN": 22700, "fatigue_load_limit_kN": 1520, "limiting_speed_rpm": 180, "max_rpm": 180, "speed_oil_rpm": 230, "weight_g": 887000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For heavy radial load with misalignment on a 1000 mm shaft, NTN supplies 239/1000K: sphered outer raceway, two roller rows, pressed-steel cage (standard execution), oil speed 230 r/min. Numbering ties 239/1000K to its envelope and execution: same-number EA versus EM or plain variants share the 1000 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. At 9550 kN C and 887000 g mass the 23900 series part is built for shock and vibration; the 236 mm-wide ring needs square abutments to keep both rows equally loaded. 1000 mm bore is 39.37 in and 1320 mm OD is 51.969 in; the ISO 15 envelope swaps between brands, but the 9550/22700 kN ratings and cage design are NTN 2203E values. Mount 239/1000K on its adapter or withdrawal sleeve on the 1000 mm plain shaft: oil the sleeve, fit the lock nut, drive up to the NTN-specified residual clearance (or use oil injection on large seats), then lock the tab washer.", "applications": [ "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "cage damage when a mounting force is applied through the roller set instead of the ring face", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "hard-particle indentation through the open arrangement in dusty mining duty", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient" ], "pitfalls": [ "At 1000 mm bore 239/1000K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 236 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 236 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 236 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 180 r/min grease rating is lost to abrasive wear long before fatigue.", "The 9550/22700 kN ratings, 1520 kN Pu and 887000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1000K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1000K?", "a": "239/1000K is an NTN double-row spherical roller bearing to ISO 15: 1000 mm bore, 1320 mm OD and 236 mm width (39.37 × 51.969 × 9.291 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 9550 kN, C0 22700 kN, Pu 1520 kN, grease limiting speed 180 r/min, oil 230 r/min, mass about 887000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/1000K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/1000." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1000K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1000K?", "a": "239/1000K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1000K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 9550 kN C / 22700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1000", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-1000 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1000k", "239-1000K" ], "locale_variants": {} }, { "sku": "230-1000B", "brand": "NTN", "manufacturer_designation": "NTN 230/1000B", "series": "23000-series", "type": "spherical_roller", "d_mm": 1000, "D_mm": 1420, "B_mm": 308, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 13800, "static_load_kN": 30000, "fatigue_load_limit_kN": 1460, "limiting_speed_rpm": 170, "max_rpm": 170, "speed_oil_rpm": 220, "weight_g": 1580000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "230/1000B belongs to the 23000 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. Numbering ties 230/1000B to its envelope and execution: same-number EA versus EM or plain variants share the 1000 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Pu 1460 kN is the catalogue fatigue load limit for 230/1000B, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. Equivalent-load planning keeps a radial plus moderate axial combination on 230/1000B; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. Fillet radii on shaft and housing must clear the ring chamfers of the 308 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.", "applications": [ "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 1000 mm bore 230/1000B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Do not confuse EA and EM at the same number: 230/1000B carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 1000×1420 mm envelope is identical.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 230/1000B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 1000 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 230/1000B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The 13800/30000 kN ratings, 1460 kN Pu and 1580000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/1000B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/1000B?", "a": "230/1000B is an NTN double-row spherical roller bearing to ISO 15: 1000 mm bore, 1420 mm OD and 308 mm width (39.37 × 55.906 × 12.126 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 13800 kN, C0 30000 kN, Pu 1460 kN, grease limiting speed 170 r/min, oil 220 r/min, mass about 1580000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "230/1000B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 230/1000BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/1000B is the basic execution." }, { "q": "What do D1 and W33 mean on 230/1000B?", "a": "230/1000B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/1000B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 13800 kN C / 30000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-1000BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 230-1000BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-1000b", "230-1000B" ], "locale_variants": {} }, { "sku": "230-1000BK", "brand": "NTN", "manufacturer_designation": "NTN 230/1000BK", "series": "23000-series", "type": "spherical_roller", "d_mm": 1000, "D_mm": 1420, "B_mm": 308, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 13800, "static_load_kN": 30000, "fatigue_load_limit_kN": 1460, "limiting_speed_rpm": 170, "max_rpm": 170, "speed_oil_rpm": 220, "weight_g": 1520000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NTN lists 230/1000BK with a 1:12 tapered bore (K) and plain outer ring (no D1/W33 groove): 1000 mm bore, 1420 mm OD, 308 mm width, rated 170 r/min on grease. Digit by digit the code reads as spherical-roller dimension series plus 1000 mm bore; the 308 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. Suffix reading on 230/1000BK: the bare number is the standard open execution; K marks the 1:12 tapered bore; B marks the standard large-bore internal design on slash-size 230–232 series; quote the full code because each suffix is a distinct article. 1000 mm bore is 39.37 in and 1420 mm OD is 55.906 in; the ISO 15 envelope swaps between brands, but the 13800/30000 kN ratings and cage design are NTN 2203E values. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 1000 mm bore assembly by hand to distribute it across both rows.", "applications": [ "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "roller-end smearing during skidding starts under light load and high viscosity grease", "false brinelling on stopped machines exposed to screen or crusher vibration", "rolling-contact fatigue after the catalogue L10 life at the actual load" ], "pitfalls": [ "At 1000 mm bore 230/1000BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 13800 kN rating no longer applies.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1000 mm bearing, and drive-up procedures differ.", "Minimum load must be maintained even at rest under vibration: an unloaded 230/1000BK on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 308 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The 13800/30000 kN ratings, 1460 kN Pu and 1520000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/1000BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/1000BK?", "a": "230/1000BK is an NTN double-row spherical roller bearing to ISO 15: 1000 mm bore, 1420 mm OD and 308 mm width (39.37 × 55.906 × 12.126 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 13800 kN, C0 30000 kN, Pu 1460 kN, grease limiting speed 170 r/min, oil 220 r/min, mass about 1520000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 230/1000BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 230/1000B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/1000BK is the basic execution." }, { "q": "What do D1 and W33 mean on 230/1000BK?", "a": "230/1000BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/1000BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 13800 kN C / 30000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-1000B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 230-1000B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-1000bk", "230-1000BK" ], "locale_variants": {} }, { "sku": "240-1000B", "brand": "NTN", "manufacturer_designation": "NTN 240/1000B", "series": "24000-series", "type": "spherical_roller", "d_mm": 1000, "D_mm": 1420, "B_mm": 412, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 17800, "static_load_kN": 42000, "fatigue_load_limit_kN": 1890, "limiting_speed_rpm": 150, "max_rpm": 150, "speed_oil_rpm": 190, "weight_g": 2110000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, 240/1000B denotes the 1000 mm bore spherical roller bearing (17800 kN C / 42000 kN C0) in the 24000 series, the self-aligning choice for heavy combined load. The leading digits are the ISO 15 dimension series (24000 series); the bore code resolves to 1000 mm (two-digit code ×5, with the 00–03 exception table), and 1420 mm OD / 412 mm width follow the general plan. Open by design, 240/1000B requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. 1000 mm bore is 39.37 in and 1420 mm OD is 55.906 in; the ISO 15 envelope swaps between brands, but the 17800/42000 kN ratings and cage design are NTN 2203E values. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "roller-end smearing during skidding starts under light load and high viscosity grease", "false brinelling on stopped machines exposed to screen or crusher vibration", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range" ], "pitfalls": [ "At 1000 mm bore 240/1000B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1000 mm bearing, and drive-up procedures differ.", "Oil relubrication toward 190 r/min needs drain and level design; flooding the 412 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Minimum load must be maintained even at rest under vibration: an unloaded 240/1000B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 17800 kN rating no longer applies.", "The 17800/42000 kN ratings, 1890 kN Pu and 2110000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/1000B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/1000B?", "a": "240/1000B is an NTN double-row spherical roller bearing to ISO 15: 1000 mm bore, 1420 mm OD and 412 mm width (39.37 × 55.906 × 16.22 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 17800 kN, C0 42000 kN, Pu 1890 kN, grease limiting speed 150 r/min, oil 190 r/min, mass about 2110000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "240/1000B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 240/1000BK30 (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/1000B is the basic execution." }, { "q": "What do D1 and W33 mean on 240/1000B?", "a": "240/1000B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/1000B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 17800 kN C / 42000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-1000BK30", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 240-1000BK30 (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-1000b", "240-1000B" ], "locale_variants": {} }, { "sku": "240-1000BK30", "brand": "NTN", "manufacturer_designation": "NTN 240/1000BK30", "series": "24000-series", "type": "spherical_roller", "d_mm": 1000, "D_mm": 1420, "B_mm": 412, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 17800, "static_load_kN": 42000, "fatigue_load_limit_kN": 1890, "limiting_speed_rpm": 150, "max_rpm": 150, "speed_oil_rpm": 190, "weight_g": 2080000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "240/1000BK30 is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 1000×1420×412 mm to ISO 15, with pressed-steel cage (standard execution). The leading digits are the ISO 15 dimension series (24000 series); the bore code resolves to 1000 mm (two-digit code ×5, with the 00–03 exception table), and 1420 mm OD / 412 mm width follow the general plan. Suffix reading on 240/1000BK30: the bare number is the standard open execution; K30 marks the 1:30 tapered bore of the wide series; B marks the standard large-bore internal design on slash-size 230–232 series; quote the full code because each suffix is a distinct article. Catalogue mass 2080000 g (2080.00 kg) for the 1000×1420×412 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 1000 mm set.", "applications": [ "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "water-induced pitting in washdown or outdoor duty without effective external seals", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 1000 mm bore 240/1000BK30 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The 1:30 tapered bore is the only difference from the cylindrical-bore 240/1000B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "Never substitute 240/1000BK30 by envelope alone: the 42000 kN C0 and 1890 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1000 mm bearing, and drive-up procedures differ.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 412 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The 17800/42000 kN ratings, 1890 kN Pu and 2080000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/1000BK30 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/1000BK30?", "a": "240/1000BK30 is an NTN double-row spherical roller bearing to ISO 15: 1000 mm bore, 1420 mm OD and 412 mm width (39.37 × 55.906 × 16.22 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 17800 kN, C0 42000 kN, Pu 1890 kN, grease limiting speed 150 r/min, oil 190 r/min, mass about 2080000 g. It is open, with pressed-steel cage (standard execution) and a 1:30 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K30 denotes a 1:30 tapered bore (the wide 24000 series). 240/1000BK30 mounts on a matching adapter or withdrawal sleeve on a plain 1000 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 240/1000B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/1000BK30 is the basic execution." }, { "q": "What do D1 and W33 mean on 240/1000BK30?", "a": "240/1000BK30 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/1000BK30 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 17800 kN C / 42000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-1000B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 240-1000B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-1000bk30", "240-1000BK30" ], "locale_variants": {} }, { "sku": "239-1060", "brand": "NTN", "manufacturer_designation": "NTN 239/1060", "series": "23900-series", "type": "spherical_roller", "d_mm": 1060, "D_mm": 1400, "B_mm": 250, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 10400, "static_load_kN": 24700, "fatigue_load_limit_kN": 1670, "limiting_speed_rpm": 160, "max_rpm": 160, "speed_oil_rpm": 210, "weight_g": 1090000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "The NTN order number 239/1060 identifies a 1060×1400×250 mm (41.732 × 55.118 × 9.843 in) spherical roller bearing, cylindrical bore, to the ISO 15 boundary plan. Digit by digit the code reads as spherical-roller dimension series plus 1060 mm bore; the 250 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. Pu 1670 kN is the catalogue fatigue load limit for 239/1060, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. Catalogue mass 1090000 g (1090.00 kg) for the 1060×1400×250 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 1060 mm set.", "applications": [ "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "false brinelling on stopped machines exposed to screen or crusher vibration", "water-induced pitting in washdown or outdoor duty without effective external seals" ], "pitfalls": [ "At 1060 mm bore 239/1060 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 250 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 10400 kN rating no longer applies.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 250 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 239/1060 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The 10400/24700 kN ratings, 1670 kN Pu and 1090000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1060 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1060?", "a": "239/1060 is an NTN double-row spherical roller bearing to ISO 15: 1060 mm bore, 1400 mm OD and 250 mm width (41.732 × 55.118 × 9.843 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 10400 kN, C0 24700 kN, Pu 1670 kN, grease limiting speed 160 r/min, oil 210 r/min, mass about 1090000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/1060 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/1060K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1060 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1060?", "a": "239/1060 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1060 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 10400 kN C / 24700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1060K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-1060K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1060" ], "locale_variants": {} }, { "sku": "239-1060K", "brand": "NTN", "manufacturer_designation": "NTN 239/1060K", "series": "23900-series", "type": "spherical_roller", "d_mm": 1060, "D_mm": 1400, "B_mm": 250, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 10400, "static_load_kN": 24700, "fatigue_load_limit_kN": 1670, "limiting_speed_rpm": 160, "max_rpm": 160, "speed_oil_rpm": 210, "weight_g": 1060000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NTN lists 239/1060K with a 1:12 tapered bore (K) and plain outer ring (no D1/W33 groove): 1060 mm bore, 1400 mm OD, 250 mm width, rated 160 r/min on grease. The leading digits are the ISO 15 dimension series (23900 series); the bore code resolves to 1060 mm (two-digit code ×5, with the 00–03 exception table), and 1400 mm OD / 250 mm width follow the general plan. Suffix reading on 239/1060K: the bare number is the standard open execution; K marks the 1:12 tapered bore; quote the full code because each suffix is a distinct article. Grease/oil ratio: the 160 r/min limiting value is .76 of the 210 r/min oil value; heavy 250 mm-wide cages run hot in churning grease, so quantity and groove supply both matter. Fillet radii on shaft and housing must clear the ring chamfers of the 250 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.", "applications": [ "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "brinelling from static overload or a hammer blow during sleeve mounting", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient" ], "pitfalls": [ "At 1060 mm bore 239/1060K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 250 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 1060 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "Never substitute 239/1060K by envelope alone: the 24700 kN C0 and 1670 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 250 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The 10400/24700 kN ratings, 1670 kN Pu and 1060000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1060K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1060K?", "a": "239/1060K is an NTN double-row spherical roller bearing to ISO 15: 1060 mm bore, 1400 mm OD and 250 mm width (41.732 × 55.118 × 9.843 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 10400 kN, C0 24700 kN, Pu 1670 kN, grease limiting speed 160 r/min, oil 210 r/min, mass about 1060000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/1060K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/1060." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1060K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1060K?", "a": "239/1060K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1060K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 10400 kN C / 24700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1060", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-1060 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1060k", "239-1060K" ], "locale_variants": {} }, { "sku": "230-1060B", "brand": "NTN", "manufacturer_designation": "NTN 230/1060B", "series": "23000-series", "type": "spherical_roller", "d_mm": 1060, "D_mm": 1500, "B_mm": 325, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 15100, "static_load_kN": 33500, "fatigue_load_limit_kN": 1610, "limiting_speed_rpm": 150, "max_rpm": 150, "speed_oil_rpm": 200, "weight_g": 1850000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For heavy radial load with misalignment on a 1060 mm shaft, NTN supplies 230/1060B: sphered outer raceway, two roller rows, pressed-steel cage (standard execution), oil speed 200 r/min. Numbering ties 230/1060B to its envelope and execution: same-number EA versus EM or plain variants share the 1060 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Open by design, 230/1060B requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. Grease/oil ratio: the 150 r/min limiting value is .75 of the 200 r/min oil value; heavy 325 mm-wide cages run hot in churning grease, so quantity and groove supply both matter. Never mount 230/1060B by striking the outer ring through the roller set; drive through ring faces (or the adapter sleeve nut) and support the ring square to avoid brinelling the 1500 mm race.", "applications": [ "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "rolling-contact fatigue after the catalogue L10 life at the actual load", "water-induced pitting in washdown or outdoor duty without effective external seals" ], "pitfalls": [ "At 1060 mm bore 230/1060B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 325 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Never substitute 230/1060B by envelope alone: the 33500 kN C0 and 1610 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 325 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 15100 kN rating no longer applies.", "The 15100/33500 kN ratings, 1610 kN Pu and 1850000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/1060B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/1060B?", "a": "230/1060B is an NTN double-row spherical roller bearing to ISO 15: 1060 mm bore, 1500 mm OD and 325 mm width (41.732 × 59.055 × 12.795 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 15100 kN, C0 33500 kN, Pu 1610 kN, grease limiting speed 150 r/min, oil 200 r/min, mass about 1850000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "230/1060B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 230/1060BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/1060B is the basic execution." }, { "q": "What do D1 and W33 mean on 230/1060B?", "a": "230/1060B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/1060B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 15100 kN C / 33500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-1060BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 230-1060BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-1060b", "230-1060B" ], "locale_variants": {} }, { "sku": "230-1060BK", "brand": "NTN", "manufacturer_designation": "NTN 230/1060BK", "series": "23000-series", "type": "spherical_roller", "d_mm": 1060, "D_mm": 1500, "B_mm": 325, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 15100, "static_load_kN": 33500, "fatigue_load_limit_kN": 1610, "limiting_speed_rpm": 150, "max_rpm": 150, "speed_oil_rpm": 200, "weight_g": 1790000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For heavy radial load with misalignment on a 1060 mm shaft, NTN supplies 230/1060BK: sphered outer raceway, two roller rows, pressed-steel cage (standard execution), oil speed 200 r/min. The leading digits are the ISO 15 dimension series (23000 series); the bore code resolves to 1060 mm (two-digit code ×5, with the 00–03 exception table), and 1500 mm OD / 325 mm width follow the general plan. The plain outer ring (no D1/W33 groove) makes relubrication part of the design: fresh grease reaches the rolling elements through the outer-ring feature rather than relying solely on end-side packing. Speed planning: 150 r/min grease limiting speed is the cage/kinematic ceiling and 200 r/min is the oil-lubricated value for the 1060 mm bore; vibrating screens rarely approach either and are load/cage limited instead. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 1060 mm set.", "applications": [ "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "brinelling from static overload or a hammer blow during sleeve mounting", "rolling-contact fatigue after the catalogue L10 life at the actual load" ], "pitfalls": [ "At 1060 mm bore 230/1060BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Oil relubrication toward 200 r/min needs drain and level design; flooding the 325 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 15100 kN rating no longer applies.", "Never substitute 230/1060BK by envelope alone: the 33500 kN C0 and 1610 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1060 mm bearing, and drive-up procedures differ.", "The 15100/33500 kN ratings, 1610 kN Pu and 1790000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/1060BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/1060BK?", "a": "230/1060BK is an NTN double-row spherical roller bearing to ISO 15: 1060 mm bore, 1500 mm OD and 325 mm width (41.732 × 59.055 × 12.795 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 15100 kN, C0 33500 kN, Pu 1610 kN, grease limiting speed 150 r/min, oil 200 r/min, mass about 1790000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 230/1060BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 230/1060B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/1060BK is the basic execution." }, { "q": "What do D1 and W33 mean on 230/1060BK?", "a": "230/1060BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/1060BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 15100 kN C / 33500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-1060B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 230-1060B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-1060bk", "230-1060BK" ], "locale_variants": {} }, { "sku": "240-1060B", "brand": "NTN", "manufacturer_designation": "NTN 240/1060B", "series": "24000-series", "type": "spherical_roller", "d_mm": 1060, "D_mm": 1500, "B_mm": 438, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 19800, "static_load_kN": 47000, "fatigue_load_limit_kN": 2060, "limiting_speed_rpm": 140, "max_rpm": 140, "speed_oil_rpm": 180, "weight_g": 2450000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "240/1060B belongs to the 24000 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. Digit by digit the code reads as spherical-roller dimension series plus 1060 mm bore; the 438 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. The bearing accepts predominantly radial load with a moderate axial share, but is not a pure thrust bearing: sustained axial-only load skids the unloaded row and damages the basic cage. Grease/oil ratio: the 140 r/min limiting value is .78 of the 180 r/min oil value; heavy 438 mm-wide cages run hot in churning grease, so quantity and groove supply both matter. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 1060 mm set.", "applications": [ "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "roller-end smearing during skidding starts under light load and high viscosity grease", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range" ], "pitfalls": [ "At 1060 mm bore 240/1060B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1060 mm bearing, and drive-up procedures differ.", "Do not confuse EA and EM at the same number: 240/1060B carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 1060×1500 mm envelope is identical.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 140 r/min grease rating is lost to abrasive wear long before fatigue.", "Never substitute 240/1060B by envelope alone: the 47000 kN C0 and 2060 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "The 19800/47000 kN ratings, 2060 kN Pu and 2450000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/1060B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/1060B?", "a": "240/1060B is an NTN double-row spherical roller bearing to ISO 15: 1060 mm bore, 1500 mm OD and 438 mm width (41.732 × 59.055 × 17.244 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 19800 kN, C0 47000 kN, Pu 2060 kN, grease limiting speed 140 r/min, oil 180 r/min, mass about 2450000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "240/1060B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 240/1060BK30 (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/1060B is the basic execution." }, { "q": "What do D1 and W33 mean on 240/1060B?", "a": "240/1060B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/1060B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 19800 kN C / 47000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-1060BK30", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 240-1060BK30 (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-1060b", "240-1060B" ], "locale_variants": {} }, { "sku": "240-1060BK30", "brand": "NTN", "manufacturer_designation": "NTN 240/1060BK30", "series": "24000-series", "type": "spherical_roller", "d_mm": 1060, "D_mm": 1500, "B_mm": 438, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 19800, "static_load_kN": 47000, "fatigue_load_limit_kN": 2060, "limiting_speed_rpm": 140, "max_rpm": 140, "speed_oil_rpm": 180, "weight_g": 2140000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "240/1060BK30 is the basic execution of NTN's spherical roller range for a 1060 mm shaft — 19800 kN basic dynamic capacity in a 2140000 g, open ISO 15 envelope. The leading digits are the ISO 15 dimension series (24000 series); the bore code resolves to 1060 mm (two-digit code ×5, with the 00–03 exception table), and 1500 mm OD / 438 mm width follow the general plan. The sphered outer raceway lets the inner-ring assembly pivot, accommodating shaft deflection and housing misalignment (around 1–2° for this class; use the 2203E value for the exact series) without edge loading the rollers. The 220.0 mm section height hosts the spherical roller geometry; shaft and housing fillet radii must clear the chamfer table so the 438 mm-wide ring seats fully on both sides. Fillet radii on shaft and housing must clear the ring chamfers of the 438 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.", "applications": [ "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "false brinelling on stopped machines exposed to screen or crusher vibration", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 1060 mm bore 240/1060BK30 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Oil relubrication toward 180 r/min needs drain and level design; flooding the 438 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 240/1060BK30 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "Minimum load must be maintained even at rest under vibration: an unloaded 240/1060BK30 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Minimum load must be maintained even at rest under vibration: an unloaded 240/1060BK30 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The 19800/47000 kN ratings, 2060 kN Pu and 2140000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/1060BK30 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/1060BK30?", "a": "240/1060BK30 is an NTN double-row spherical roller bearing to ISO 15: 1060 mm bore, 1500 mm OD and 438 mm width (41.732 × 59.055 × 17.244 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 19800 kN, C0 47000 kN, Pu 2060 kN, grease limiting speed 140 r/min, oil 180 r/min, mass about 2140000 g. It is open, with pressed-steel cage (standard execution) and a 1:30 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K30 denotes a 1:30 tapered bore (the wide 24000 series). 240/1060BK30 mounts on a matching adapter or withdrawal sleeve on a plain 1060 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 240/1060B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/1060BK30 is the basic execution." }, { "q": "What do D1 and W33 mean on 240/1060BK30?", "a": "240/1060BK30 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/1060BK30 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 19800 kN C / 47000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-1060B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 240-1060B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-1060bk30", "240-1060BK30" ], "locale_variants": {} }, { "sku": "239-1120", "brand": "NTN", "manufacturer_designation": "NTN 239/1120", "series": "23900-series", "type": "spherical_roller", "d_mm": 1120, "D_mm": 1460, "B_mm": 250, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 10900, "static_load_kN": 26700, "fatigue_load_limit_kN": 1470, "limiting_speed_rpm": 150, "max_rpm": 150, "speed_oil_rpm": 200, "weight_g": 1140000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NTN lists 239/1120 with a cylindrical bore and plain outer ring (no D1/W33 groove): 1120 mm bore, 1460 mm OD, 250 mm width, rated 150 r/min on grease. Numbering ties 239/1120 to its envelope and execution: same-number EA versus EM or plain variants share the 1120 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Suffix reading on 239/1120: the bare number is the standard open execution; quote the full code because each suffix is a distinct article. Pu 1470 kN against C0 26700 kN anchors the contamination derating; for dirty mining duty the adjusted life of 239/1120 moves with cleanliness far more than with small C variations. Fillet radii on shaft and housing must clear the ring chamfers of the 250 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.", "applications": [ "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "cage damage when a mounting force is applied through the roller set instead of the ring face", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "brinelling from static overload or a hammer blow during sleeve mounting", "rolling-contact fatigue after the catalogue L10 life at the actual load" ], "pitfalls": [ "At 1120 mm bore 239/1120 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 250 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "Never substitute 239/1120 by envelope alone: the 26700 kN C0 and 1470 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1120 mm bearing, and drive-up procedures differ.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 250 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The 10900/26700 kN ratings, 1470 kN Pu and 1140000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1120 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1120?", "a": "239/1120 is an NTN double-row spherical roller bearing to ISO 15: 1120 mm bore, 1460 mm OD and 250 mm width (44.094 × 57.48 × 9.843 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 10900 kN, C0 26700 kN, Pu 1470 kN, grease limiting speed 150 r/min, oil 200 r/min, mass about 1140000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/1120 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/1120K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1120 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1120?", "a": "239/1120 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1120 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 10900 kN C / 26700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1120K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-1120K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1120" ], "locale_variants": {} }, { "sku": "239-1120K", "brand": "NTN", "manufacturer_designation": "NTN 239/1120K", "series": "23900-series", "type": "spherical_roller", "d_mm": 1120, "D_mm": 1460, "B_mm": 250, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 10900, "static_load_kN": 26700, "fatigue_load_limit_kN": 1470, "limiting_speed_rpm": 150, "max_rpm": 150, "speed_oil_rpm": 200, "weight_g": 1100000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "239/1120K belongs to the 23900 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. Reading the full code: the number gives the 1120×1460 mm envelope, — names the cage/capacity execution, K marks the 1:12 tapered bore for adapter/withdrawal-sleeve mounting, and plain outer ring (no D1/W33 groove) completes the order number. The plain outer ring (no D1/W33 groove) makes relubrication part of the design: fresh grease reaches the rolling elements through the outer-ring feature rather than relying solely on end-side packing. 1120 mm bore is 44.094 in and 1460 mm OD is 57.48 in; the ISO 15 envelope swaps between brands, but the 10900/26700 kN ratings and cage design are NTN 2203E values. On vibrating-duty shafts verify the radial clearance class and cage choice at order time; the open 239/1120K leaves sealing and the C3/C4 clearance decision to the application drawing.", "applications": [ "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "water-induced pitting in washdown or outdoor duty without effective external seals", "hard-particle indentation through the open arrangement in dusty mining duty" ], "pitfalls": [ "At 1120 mm bore 239/1120K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 150 r/min grease rating is lost to abrasive wear long before fatigue.", "Minimum load must be maintained even at rest under vibration: an unloaded 239/1120K on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Minimum load must be maintained even at rest under vibration: an unloaded 239/1120K on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1120 mm bearing, and drive-up procedures differ.", "The 10900/26700 kN ratings, 1470 kN Pu and 1100000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1120K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1120K?", "a": "239/1120K is an NTN double-row spherical roller bearing to ISO 15: 1120 mm bore, 1460 mm OD and 250 mm width (44.094 × 57.48 × 9.843 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 10900 kN, C0 26700 kN, Pu 1470 kN, grease limiting speed 150 r/min, oil 200 r/min, mass about 1100000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/1120K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/1120." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1120K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1120K?", "a": "239/1120K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1120K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 10900 kN C / 26700 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1120", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-1120 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1120k", "239-1120K" ], "locale_variants": {} }, { "sku": "230-1120B", "brand": "NTN", "manufacturer_designation": "NTN 230/1120B", "series": "23000-series", "type": "spherical_roller", "d_mm": 1120, "D_mm": 1580, "B_mm": 345, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 17400, "static_load_kN": 39000, "fatigue_load_limit_kN": 2310, "limiting_speed_rpm": 150, "max_rpm": 150, "speed_oil_rpm": 190, "weight_g": 2160000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, 230/1120B denotes the 1120 mm bore spherical roller bearing (17400 kN C / 39000 kN C0) in the 23000 series, the self-aligning choice for heavy combined load. Digit by digit the code reads as spherical-roller dimension series plus 1120 mm bore; the 345 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. Open by design, 230/1120B requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. Grease/oil ratio: the 150 r/min limiting value is .79 of the 190 r/min oil value; heavy 345 mm-wide cages run hot in churning grease, so quantity and groove supply both matter. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 1120 mm bore assembly by hand to distribute it across both rows.", "applications": [ "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "brinelling from static overload or a hammer blow during sleeve mounting", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient" ], "pitfalls": [ "At 1120 mm bore 230/1120B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 150 r/min grease rating is lost to abrasive wear long before fatigue.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 17400 kN rating no longer applies.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 1120 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 17400 kN rating no longer applies.", "The 17400/39000 kN ratings, 2310 kN Pu and 2160000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/1120B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/1120B?", "a": "230/1120B is an NTN double-row spherical roller bearing to ISO 15: 1120 mm bore, 1580 mm OD and 345 mm width (44.094 × 62.205 × 13.583 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 17400 kN, C0 39000 kN, Pu 2310 kN, grease limiting speed 150 r/min, oil 190 r/min, mass about 2160000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "230/1120B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 230/1120BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/1120B is the basic execution." }, { "q": "What do D1 and W33 mean on 230/1120B?", "a": "230/1120B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/1120B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 17400 kN C / 39000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-1120BK", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 230-1120BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-1120b", "230-1120B" ], "locale_variants": {} }, { "sku": "230-1120BK", "brand": "NTN", "manufacturer_designation": "NTN 230/1120BK", "series": "23000-series", "type": "spherical_roller", "d_mm": 1120, "D_mm": 1580, "B_mm": 345, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 17400, "static_load_kN": 39000, "fatigue_load_limit_kN": 2310, "limiting_speed_rpm": 150, "max_rpm": 150, "speed_oil_rpm": 190, "weight_g": 2090000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "230/1120BK belongs to the 23000 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. The leading digits are the ISO 15 dimension series (23000 series); the bore code resolves to 1120 mm (two-digit code ×5, with the 00–03 exception table), and 1580 mm OD / 345 mm width follow the general plan. Pu 2310 kN is the catalogue fatigue load limit for 230/1120BK, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. Selection: the C0/C ratio of 2.24 (39000/17400 kN) reflects the heavy static and shock proportioning of 230/1120BK; size the equivalent load at the required L10 with shock factor for the application. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "hard-particle indentation through the open arrangement in dusty mining duty", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 1120 mm bore 230/1120BK is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The 1:12 tapered bore is the only difference from the cylindrical-bore 230/1120B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1120 mm bearing, and drive-up procedures differ.", "The 1:12 tapered bore is the only difference from the cylindrical-bore 230/1120B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 230/1120BK in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The 17400/39000 kN ratings, 2310 kN Pu and 2090000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/1120BK (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 230/1120BK?", "a": "230/1120BK is an NTN double-row spherical roller bearing to ISO 15: 1120 mm bore, 1580 mm OD and 345 mm width (44.094 × 62.205 × 13.583 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 17400 kN, C0 39000 kN, Pu 2310 kN, grease limiting speed 150 r/min, oil 190 r/min, mass about 2090000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 230/1120BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 230/1120B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 230/1120BK is the basic execution." }, { "q": "What do D1 and W33 mean on 230/1120BK?", "a": "230/1120BK is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 230/1120BK take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 17400 kN C / 39000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "230-1120B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 230-1120B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "230-1120bk", "230-1120BK" ], "locale_variants": {} }, { "sku": "240-1120B", "brand": "NTN", "manufacturer_designation": "NTN 240/1120B", "series": "24000-series", "type": "spherical_roller", "d_mm": 1120, "D_mm": 1580, "B_mm": 462, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 21700, "static_load_kN": 52500, "fatigue_load_limit_kN": 2230, "limiting_speed_rpm": 120, "max_rpm": 120, "speed_oil_rpm": 160, "weight_g": 2890000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "240/1120B is the basic execution of NTN's spherical roller range for a 1120 mm shaft — 21700 kN basic dynamic capacity in a 2890000 g, open ISO 15 envelope. On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (cylindrical), lubrication feature (none); 240/1120B is assembled exactly in that order. The 230.0 mm radial section over the 1120 mm bore carries two roller rows; capacity per millimetre of bore is about 19.4 kN/mm, among the highest of rolling bearings for the ISO 15 envelope. 1120 mm bore is 44.094 in and 1580 mm OD is 62.205 in; the ISO 15 envelope swaps between brands, but the 21700/52500 kN ratings and cage design are NTN 2203E values. Fit the cylindrical-bore 240/1120B with the inner ring heated (max 120 °C) for the shaft interference; the outer ring slides into the housing with its spherical seat able to pivot after seating.", "applications": [ "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "rolling-contact fatigue after the catalogue L10 life at the actual load", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient" ], "pitfalls": [ "At 1120 mm bore 240/1120B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Do not confuse EA and EM at the same number: 240/1120B carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 1120×1580 mm envelope is identical.", "The cylindrical-bore 240/1120B and its tapered-bore counterpart 240/1120BK30 share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 1120 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "The cylindrical-bore 240/1120B and its tapered-bore counterpart 240/1120BK30 share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.", "The 21700/52500 kN ratings, 2230 kN Pu and 2890000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/1120B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/1120B?", "a": "240/1120B is an NTN double-row spherical roller bearing to ISO 15: 1120 mm bore, 1580 mm OD and 462 mm width (44.094 × 62.205 × 18.189 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 21700 kN, C0 52500 kN, Pu 2230 kN, grease limiting speed 120 r/min, oil 160 r/min, mass about 2890000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "240/1120B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 240/1120BK30 (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/1120B is the basic execution." }, { "q": "What do D1 and W33 mean on 240/1120B?", "a": "240/1120B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/1120B take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 21700 kN C / 52500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-1120BK30", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 240-1120BK30 (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-1120b", "240-1120B" ], "locale_variants": {} }, { "sku": "240-1120BK30", "brand": "NTN", "manufacturer_designation": "NTN 240/1120BK30", "series": "24000-series", "type": "spherical_roller", "d_mm": 1120, "D_mm": 1580, "B_mm": 462, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 21700, "static_load_kN": 52500, "fatigue_load_limit_kN": 2230, "limiting_speed_rpm": 120, "max_rpm": 120, "speed_oil_rpm": 160, "weight_g": 2840000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "240/1120BK30 belongs to the 24000 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. Reading the full code: the number gives the 1120×1580 mm envelope, — names the cage/capacity execution, K30 marks the 1:30 tapered bore for sleeve mounting, and plain outer ring (no D1/W33 groove) completes the order number. Suffix reading on 240/1120BK30: the bare number is the standard open execution; K30 marks the 1:30 tapered bore of the wide series; B marks the standard large-bore internal design on slash-size 230–232 series; quote the full code because each suffix is a distinct article. Catalogue mass 2840000 g (2840.00 kg) for the 1120×1580×462 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. Never mount 240/1120BK30 by striking the outer ring through the roller set; drive through ring faces (or the adapter sleeve nut) and support the ring square to avoid brinelling the 1580 mm race.", "applications": [ "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "brinelling from static overload or a hammer blow during sleeve mounting", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range" ], "pitfalls": [ "At 1120 mm bore 240/1120BK30 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1120 mm bearing, and drive-up procedures differ.", "Never substitute 240/1120BK30 by envelope alone: the 52500 kN C0 and 2230 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1120 mm bearing, and drive-up procedures differ.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 462 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The 21700/52500 kN ratings, 2230 kN Pu and 2840000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/1120BK30 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 240/1120BK30?", "a": "240/1120BK30 is an NTN double-row spherical roller bearing to ISO 15: 1120 mm bore, 1580 mm OD and 462 mm width (44.094 × 62.205 × 18.189 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 21700 kN, C0 52500 kN, Pu 2230 kN, grease limiting speed 120 r/min, oil 160 r/min, mass about 2840000 g. It is open, with pressed-steel cage (standard execution) and a 1:30 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K30 denotes a 1:30 tapered bore (the wide 24000 series). 240/1120BK30 mounts on a matching adapter or withdrawal sleeve on a plain 1120 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 240/1120B." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 240/1120BK30 is the basic execution." }, { "q": "What do D1 and W33 mean on 240/1120BK30?", "a": "240/1120BK30 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 240/1120BK30 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 21700 kN C / 52500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "240-1120B", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 24000-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 240-1120B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "240-1120bk30", "240-1120BK30" ], "locale_variants": {} }, { "sku": "239-1180", "brand": "NTN", "manufacturer_designation": "NTN 239/1180", "series": "23900-series", "type": "spherical_roller", "d_mm": 1180, "D_mm": 1540, "B_mm": 272, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 12200, "static_load_kN": 29800, "fatigue_load_limit_kN": 1650, "limiting_speed_rpm": 140, "max_rpm": 140, "speed_oil_rpm": 180, "weight_g": 1390000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "239/1180 belongs to the 23900 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. The leading digits are the ISO 15 dimension series (23900 series); the bore code resolves to 1180 mm (two-digit code ×5, with the 00–03 exception table), and 1540 mm OD / 272 mm width follow the general plan. Pu 1650 kN is the catalogue fatigue load limit for 239/1180, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. The 180.0 mm section height hosts the spherical roller geometry; shaft and housing fillet radii must clear the chamfer table so the 272 mm-wide ring seats fully on both sides. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "cage damage when a mounting force is applied through the roller set instead of the ring face", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "hard-particle indentation through the open arrangement in dusty mining duty", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient" ], "pitfalls": [ "At 1180 mm bore 239/1180 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The cylindrical-bore 239/1180 and its tapered-bore counterpart 239/1180K share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 12200 kN rating no longer applies.", "The two roller rows must share load equally — a tilted spacer or unequal abutment on the 272 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 239/1180 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The 12200/29800 kN ratings, 1650 kN Pu and 1390000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1180 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1180?", "a": "239/1180 is an NTN double-row spherical roller bearing to ISO 15: 1180 mm bore, 1540 mm OD and 272 mm width (46.457 × 60.63 × 10.709 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 12200 kN, C0 29800 kN, Pu 1650 kN, grease limiting speed 140 r/min, oil 180 r/min, mass about 1390000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/1180 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/1180K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1180 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1180?", "a": "239/1180 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1180 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 12200 kN C / 29800 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1180K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-1180K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1180" ], "locale_variants": {} }, { "sku": "239-1180K", "brand": "NTN", "manufacturer_designation": "NTN 239/1180K", "series": "23900-series", "type": "spherical_roller", "d_mm": 1180, "D_mm": 1540, "B_mm": 272, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 12200, "static_load_kN": 29800, "fatigue_load_limit_kN": 1650, "limiting_speed_rpm": 140, "max_rpm": 140, "speed_oil_rpm": 180, "weight_g": 1340000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For heavy radial load with misalignment on a 1180 mm shaft, NTN supplies 239/1180K: sphered outer raceway, two roller rows, pressed-steel cage (standard execution), oil speed 180 r/min. Reading the full code: the number gives the 1180×1540 mm envelope, — names the cage/capacity execution, K marks the 1:12 tapered bore for adapter/withdrawal-sleeve mounting, and plain outer ring (no D1/W33 groove) completes the order number. Pu 1650 kN is the catalogue fatigue load limit for 239/1180K, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. With about 10.3 kN of C per millimetre of the 1180 mm bore, 239/1180K screens interchange candidates quickly — then verify cage (EA/EM), bore (K/K30) and lubrication feature (D1/W33) suffixes. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.", "applications": [ "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "cage damage when a mounting force is applied through the roller set instead of the ring face", "roller-end smearing during skidding starts under light load and high viscosity grease", "fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 1180 mm bore 239/1180K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Do not confuse EA and EM at the same number: 239/1180K carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 1180×1540 mm envelope is identical.", "Oil relubrication toward 180 r/min needs drain and level design; flooding the 272 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 140 r/min grease rating is lost to abrasive wear long before fatigue.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 239/1180K in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The 12200/29800 kN ratings, 1650 kN Pu and 1340000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1180K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1180K?", "a": "239/1180K is an NTN double-row spherical roller bearing to ISO 15: 1180 mm bore, 1540 mm OD and 272 mm width (46.457 × 60.63 × 10.709 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 12200 kN, C0 29800 kN, Pu 1650 kN, grease limiting speed 140 r/min, oil 180 r/min, mass about 1340000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/1180K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/1180." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1180K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1180K?", "a": "239/1180K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1180K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 12200 kN C / 29800 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1180", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-1180 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1180k", "239-1180K" ], "locale_variants": {} }, { "sku": "239-1250", "brand": "NTN", "manufacturer_designation": "NTN 239/1250", "series": "23900-series", "type": "spherical_roller", "d_mm": 1250, "D_mm": 1630, "B_mm": 280, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 13400, "static_load_kN": 33500, "fatigue_load_limit_kN": 1810, "limiting_speed_rpm": 120, "max_rpm": 120, "speed_oil_rpm": 160, "weight_g": 1600000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "239/1250 belongs to the 23900 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. Numbering ties 239/1250 to its envelope and execution: same-number EA versus EM or plain variants share the 1250 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Open by design, 239/1250 requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. Selection: the C0/C ratio of 2.50 (33500/13400 kN) reflects the heavy static and shock proportioning of 239/1250; size the equivalent load at the required L10 with shock factor for the application. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 1250 mm bore assembly by hand to distribute it across both rows.", "applications": [ "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "rolling-contact fatigue after the catalogue L10 life at the actual load", "hard-particle indentation through the open arrangement in dusty mining duty" ], "pitfalls": [ "At 1250 mm bore 239/1250 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Minimum load must be maintained even at rest under vibration: an unloaded 239/1250 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 239/1250 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "The cylindrical-bore 239/1250 and its tapered-bore counterpart 239/1250K share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 13400 kN rating no longer applies.", "The 13400/33500 kN ratings, 1810 kN Pu and 1600000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1250 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1250?", "a": "239/1250 is an NTN double-row spherical roller bearing to ISO 15: 1250 mm bore, 1630 mm OD and 280 mm width (49.213 × 64.173 × 11.024 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 13400 kN, C0 33500 kN, Pu 1810 kN, grease limiting speed 120 r/min, oil 160 r/min, mass about 1600000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/1250 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/1250K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1250 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1250?", "a": "239/1250 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1250 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 13400 kN C / 33500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1250K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-1250K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1250" ], "locale_variants": {} }, { "sku": "239-1250K", "brand": "NTN", "manufacturer_designation": "NTN 239/1250K", "series": "23900-series", "type": "spherical_roller", "d_mm": 1250, "D_mm": 1630, "B_mm": 280, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 13400, "static_load_kN": 33500, "fatigue_load_limit_kN": 1810, "limiting_speed_rpm": 120, "max_rpm": 120, "speed_oil_rpm": 160, "weight_g": 1550000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "239/1250K is the basic execution of NTN's spherical roller range for a 1250 mm shaft — 13400 kN basic dynamic capacity in a 1550000 g, open ISO 15 envelope. Digit by digit the code reads as spherical-roller dimension series plus 1250 mm bore; the 280 mm width is the wide ISO 15 section, which is why spherical rollers interchange dimensionally but not in cage or rating detail. The sphered outer raceway lets the inner-ring assembly pivot, accommodating shaft deflection and housing misalignment (around 1–2° for this class; use the 2203E value for the exact series) without edge loading the rollers. Equivalent-load planning keeps a radial plus moderate axial combination on 239/1250K; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 1250 mm bore assembly by hand to distribute it across both rows.", "applications": [ "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 1250 mm bore 239/1250K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Oil relubrication toward 160 r/min needs drain and level design; flooding the 280 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1250 mm bearing, and drive-up procedures differ.", "Oil relubrication toward 160 r/min needs drain and level design; flooding the 280 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Minimum load must be maintained even at rest under vibration: an unloaded 239/1250K on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The 13400/33500 kN ratings, 1810 kN Pu and 1550000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1250K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1250K?", "a": "239/1250K is an NTN double-row spherical roller bearing to ISO 15: 1250 mm bore, 1630 mm OD and 280 mm width (49.213 × 64.173 × 11.024 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 13400 kN, C0 33500 kN, Pu 1810 kN, grease limiting speed 120 r/min, oil 160 r/min, mass about 1550000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/1250K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/1250." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1250K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1250K?", "a": "239/1250K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1250K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 13400 kN C / 33500 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1250", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-1250 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1250k", "239-1250K" ], "locale_variants": {} }, { "sku": "239-1320", "brand": "NTN", "manufacturer_designation": "NTN 239/1320", "series": "23900-series", "type": "spherical_roller", "d_mm": 1320, "D_mm": 1720, "B_mm": 300, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 15100, "static_load_kN": 38000, "fatigue_load_limit_kN": 1930, "limiting_speed_rpm": 120, "max_rpm": 120, "speed_oil_rpm": 150, "weight_g": 1900000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "239/1320 belongs to the 23900 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (cylindrical), lubrication feature (none); 239/1320 is assembled exactly in that order. The 200.0 mm radial section over the 1320 mm bore carries two roller rows; capacity per millimetre of bore is about 11.4 kN/mm, among the highest of rolling bearings for the ISO 15 envelope. Selection: the C0/C ratio of 2.52 (38000/15100 kN) reflects the heavy static and shock proportioning of 239/1320; size the equivalent load at the required L10 with shock factor for the application. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 1320 mm bore assembly by hand to distribute it across both rows.", "applications": [ "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "rolling-contact fatigue after the catalogue L10 life at the actual load", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range" ], "pitfalls": [ "At 1320 mm bore 239/1320 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Never substitute 239/1320 by envelope alone: the 38000 kN C0 and 1930 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1320 mm bearing, and drive-up procedures differ.", "Never substitute 239/1320 by envelope alone: the 38000 kN C0 and 1930 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "The cylindrical-bore 239/1320 and its tapered-bore counterpart 239/1320K share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.", "The 15100/38000 kN ratings, 1930 kN Pu and 1900000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1320 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1320?", "a": "239/1320 is an NTN double-row spherical roller bearing to ISO 15: 1320 mm bore, 1720 mm OD and 300 mm width (51.969 × 67.717 × 11.811 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 15100 kN, C0 38000 kN, Pu 1930 kN, grease limiting speed 120 r/min, oil 150 r/min, mass about 1900000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/1320 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/1320K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1320 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1320?", "a": "239/1320 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1320 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 15100 kN C / 38000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1320K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-1320K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1320" ], "locale_variants": {} }, { "sku": "239-1320K", "brand": "NTN", "manufacturer_designation": "NTN 239/1320K", "series": "23900-series", "type": "spherical_roller", "d_mm": 1320, "D_mm": 1720, "B_mm": 300, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 15100, "static_load_kN": 38000, "fatigue_load_limit_kN": 1930, "limiting_speed_rpm": 120, "max_rpm": 120, "speed_oil_rpm": 150, "weight_g": 1840000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NTN lists 239/1320K with a 1:12 tapered bore (K) and plain outer ring (no D1/W33 groove): 1320 mm bore, 1720 mm OD, 300 mm width, rated 120 r/min on grease. The leading digits are the ISO 15 dimension series (23900 series); the bore code resolves to 1320 mm (two-digit code ×5, with the 00–03 exception table), and 1720 mm OD / 300 mm width follow the general plan. The plain outer ring (no D1/W33 groove) makes relubrication part of the design: fresh grease reaches the rolling elements through the outer-ring feature rather than relying solely on end-side packing. Speed planning: 120 r/min grease limiting speed is the cage/kinematic ceiling and 150 r/min is the oil-lubricated value for the 1320 mm bore; vibrating screens rarely approach either and are load/cage limited instead. Fillet radii on shaft and housing must clear the ring chamfers of the 300 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.", "applications": [ "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements", "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts" ], "failure_modes": [ "lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "micro-pitting when the EHL film is thinner than the raceway composite roughness", "brinelling from static overload or a hammer blow during sleeve mounting", "false brinelling on stopped machines exposed to screen or crusher vibration" ], "pitfalls": [ "At 1320 mm bore 239/1320K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Minimum load must be maintained even at rest under vibration: an unloaded 239/1320K on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Never substitute 239/1320K by envelope alone: the 38000 kN C0 and 1930 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 239/1320K in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.", "K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 1320 mm bearing, and drive-up procedures differ.", "The 15100/38000 kN ratings, 1930 kN Pu and 1840000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1320K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1320K?", "a": "239/1320K is an NTN double-row spherical roller bearing to ISO 15: 1320 mm bore, 1720 mm OD and 300 mm width (51.969 × 67.717 × 11.811 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 15100 kN, C0 38000 kN, Pu 1930 kN, grease limiting speed 120 r/min, oil 150 r/min, mass about 1840000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/1320K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/1320." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1320K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1320K?", "a": "239/1320K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1320K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 15100 kN C / 38000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1320", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-1320 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1320k", "239-1320K" ], "locale_variants": {} }, { "sku": "239-1400", "brand": "NTN", "manufacturer_designation": "NTN 239/1400", "series": "23900-series", "type": "spherical_roller", "d_mm": 1400, "D_mm": 1820, "B_mm": 315, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 16800, "static_load_kN": 43000, "fatigue_load_limit_kN": 2570, "limiting_speed_rpm": 100, "max_rpm": 100, "speed_oil_rpm": 130, "weight_g": 2230000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NTN lists 239/1400 with a cylindrical bore and plain outer ring (no D1/W33 groove): 1400 mm bore, 1820 mm OD, 315 mm width, rated 100 r/min on grease. Reading the full code: the number gives the 1400×1820 mm envelope, — names the cage/capacity execution, no bore suffix means cylindrical bore for a direct shaft seat, and plain outer ring (no D1/W33 groove) completes the order number. Open by design, 239/1400 requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. Selection: the C0/C ratio of 2.56 (43000/16800 kN) reflects the heavy static and shock proportioning of 239/1400; size the equivalent load at the required L10 with shock factor for the application. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 1400 mm set.", "applications": [ "large SAG/ball-mill trunnion and pinion shafts", "heavy vibrating screens and grizzly feeders", "offshore and marine propulsion shaftlines", "large wind-turbine main-shaft arrangements" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "pressed EA cage fatigue under sustained vibration when minimum load is not maintained", "roller-end smearing during skidding starts under light load and high viscosity grease", "rolling-contact fatigue after the catalogue L10 life at the actual load", "brinelling from static overload or a hammer blow during sleeve mounting" ], "pitfalls": [ "At 1400 mm bore 239/1400 is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "Never substitute 239/1400 by envelope alone: the 43000 kN C0 and 2570 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.", "Oil relubrication toward 130 r/min needs drain and level design; flooding the 315 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.", "Minimum load must be maintained even at rest under vibration: an unloaded 239/1400 on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 16800 kN rating no longer applies.", "The 16800/43000 kN ratings, 2570 kN Pu and 2230000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1400 (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1400?", "a": "239/1400 is an NTN double-row spherical roller bearing to ISO 15: 1400 mm bore, 1820 mm OD and 315 mm width (55.118 × 71.654 × 12.402 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 16800 kN, C0 43000 kN, Pu 2570 kN, grease limiting speed 100 r/min, oil 130 r/min, mass about 2230000 g. It is open, with pressed-steel cage (standard execution)." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "239/1400 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/1400K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1400 is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1400?", "a": "239/1400 is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1400 take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 16800 kN C / 43000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1400K", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-1400K (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1400" ], "locale_variants": {} }, { "sku": "239-1400K", "brand": "NTN", "manufacturer_designation": "NTN 239/1400K", "series": "23900-series", "type": "spherical_roller", "d_mm": 1400, "D_mm": 1820, "B_mm": 315, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 16800, "static_load_kN": 43000, "fatigue_load_limit_kN": 2570, "limiting_speed_rpm": 100, "max_rpm": 100, "speed_oil_rpm": 130, "weight_g": 2160000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, 239/1400K denotes the 1400 mm bore spherical roller bearing (16800 kN C / 43000 kN C0) in the 23900 series, the self-aligning choice for heavy combined load. The leading digits are the ISO 15 dimension series (23900 series); the bore code resolves to 1400 mm (two-digit code ×5, with the 00–03 exception table), and 1820 mm OD / 315 mm width follow the general plan. The sphered outer raceway lets the inner-ring assembly pivot, accommodating shaft deflection and housing misalignment (around 1–2° for this class; use the 2203E value for the exact series) without edge loading the rollers. 1400 mm bore is 55.118 in and 1820 mm OD is 71.654 in; the ISO 15 envelope swaps between brands, but the 16800/43000 kN ratings and cage design are NTN 2203E values. Mount 239/1400K on its adapter or withdrawal sleeve on the 1400 mm plain shaft: oil the sleeve, fit the lock nut, drive up to the NTN-specified residual clearance (or use oil injection on large seats), then lock the tab washer.", "applications": [ "steel-mill and heavy crusher main shafts", "mining shovel and dragline swing shafts", "cement-rotary-kiln support and trunnion rolls", "large SAG/ball-mill trunnion and pinion shafts" ], "failure_modes": [ "raceway spalling at the roller ends when misalignment or deflection concentrates the line contact", "machined EM cage wear from inadequate oil film at the cage-guiding surfaces", "sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path", "water-induced pitting in washdown or outdoor duty without effective external seals", "asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range" ], "pitfalls": [ "At 1400 mm bore 239/1400K is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.", "The 1:12 tapered bore is the only difference from the cylindrical-bore 239/1400: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.", "Minimum load must be maintained even at rest under vibration: an unloaded 239/1400K on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "Adapter-sleeve mounting requires the correct sleeve series and locknut for the 1400 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.", "Minimum load must be maintained even at rest under vibration: an unloaded 239/1400K on a stopped screen false-brinells; parking brakes and shaker isolation both matter.", "The 16800/43000 kN ratings, 2570 kN Pu and 2160000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/1400K (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives." ], "faq": [ { "q": "What are the dimensions and catalogue data of 239/1400K?", "a": "239/1400K is an NTN double-row spherical roller bearing to ISO 15: 1400 mm bore, 1820 mm OD and 315 mm width (55.118 × 71.654 × 12.402 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 16800 kN, C0 43000 kN, Pu 2570 kN, grease limiting speed 100 r/min, oil 130 r/min, mass about 2160000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore." }, { "q": "What is the difference between the K/K30 tapered bore and the cylindrical bore versions?", "a": "K denotes a 1:12 tapered bore. 239/1400K mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 239/1400." }, { "q": "What do EA and EM mean on NTN spherical roller bearings?", "a": "EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 239/1400K is the basic execution." }, { "q": "What do D1 and W33 mean on 239/1400K?", "a": "239/1400K is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope." }, { "q": "How much misalignment and axial load can 239/1400K take?", "a": "The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 16800 kN C / 43000 kN C0 — but sustained pure axial load is not recommended because it unloads one row." } ], "cross_ref": [ { "equiv_sku": "239-1400", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN 23900-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 239-1400 — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. Verify shaft arrangement." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=217", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "239-1400k", "239-1400K" ], "locale_variants": {} }, { "sku": "30302-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30302", "series": "30300-series", "type": "tapered_roller", "d_mm": 15, "D_mm": 42, "B_mm": 14.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 25.8, "static_load_kN": 20.8, "limiting_speed_rpm": 9900, "max_rpm": 9900, "speed_oil_rpm": 13000, "weight_g": 96, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30302 is the NTN 4T catalogue entry for a 15×42×14.25 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2FB, which is the maker-neutral cross-reference for the 15×42 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. Individually mounted, 30302 takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Selection: C 25.8 kN against C0 20.8 kN gives a C0/C ratio of 0.81 for the 15 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Fillet radii must clear the ring chamfers of the 42 mm cup and 15 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "agricultural implement hubs and ground-tool drives", "small gearbox input shafts with combined load", "scooter and light-powersport wheel and gear positions", "small conveyor pulley shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 15 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 30302 pair with a dial indicator rather than by feel.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 15 mm bore; do not swap to the lighter family without re-checking the 9,900 r/min grease limit and the thrust load split.", "Grease packs must leave free volume in the 14.25 mm-wide set; over-greasing a paired bearing churning at the 13,000 r/min oil-band speed raises temperature and destroys the preload setting.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30302 by size alone can deliver the wrong contact-angle execution for a pinion position.", "Never fit the 15 mm cone by hammering the 42 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 25.8/20.8 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30302 (ISO 355 2FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30302?", "a": "30302 is a metric 4T tapered roller bearing to ISO 355: 15 mm bore, 42 mm outside diameter and 14.25 mm assembled width T (0.591 × 1.654 × 0.561 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 25.8 kN, C0 20.8 kN (2203E prints no Pu for this size), grease limiting speed 9,900 r/min, oil speed 13,000 r/min, mass about 96 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30302?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30302); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30302 designation encode the 15 mm bore and what is 2FB?", "a": "last two digits 02 are the ISO bore code, ×5 = 15 mm (codes 00–03 use the 10/12/15/17 exception table). The 42 mm OD and 14.25 mm assembled T follow the ISO 355 dimension-series plan. 2FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30302 list two speeds, 9,900 and 13,000 r/min?", "a": "The lower figure, 9,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30302 at 13,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30302 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30302", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fb", "4t-30302", "30302", "30302-NTN" ], "locale_variants": {} }, { "sku": "30203-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30203", "series": "30200-series", "type": "tapered_roller", "d_mm": 17, "D_mm": 40, "B_mm": 13.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 22.7, "static_load_kN": 20.3, "limiting_speed_rpm": 9900, "max_rpm": 9900, "speed_oil_rpm": 13000, "weight_g": 80, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30203 is the NTN 4T catalogue entry for a 17×40×13.25 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30203 by the metric ISO 355 number (ISO series abbreviation 2DB): 17 mm bore, 40 mm OD. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 30203, since running clearance is set during assembly. The 1.3 kN-per-mm-bore capacity figure for 30203 summarises the 22.7 kN rating over 17 mm bore; use it to sanity-check an interchange candidate before swapping brands. Fillet radii must clear the ring chamfers of the 40 mm cup and 17 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "scooter and light-powersport wheel and gear positions", "small conveyor pulley shafts", "steering-knuckle and kingpin positions", "small automotive wheel hubs and trailer axles" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 17 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 30203 pair with a dial indicator rather than by feel.", "The standard-section 30200 family at 17 mm bore (40×13.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 13,000 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 30203 at a large fraction of 9,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 17 mm shoulder geometry, because retrofitting flips the cups.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 17 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 22.7/20.3 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30203 (ISO 355 2DB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30203?", "a": "30203 is a metric 4T tapered roller bearing to ISO 355: 17 mm bore, 40 mm outside diameter and 13.25 mm assembled width T (0.669 × 1.575 × 0.522 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 22.7 kN, C0 20.3 kN (2203E prints no Pu for this size), grease limiting speed 9,900 r/min, oil speed 13,000 r/min, mass about 80 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30203?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30203); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30203 designation encode the 17 mm bore and what is 2DB?", "a": "last two digits 03 are the ISO bore code, ×5 = 17 mm (codes 00–03 use the 10/12/15/17 exception table). The 40 mm OD and 13.25 mm assembled T follow the ISO 355 dimension-series plan. 2DB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30203 list two speeds, 9,900 and 13,000 r/min?", "a": "The lower figure, 9,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30203 at 13,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30203 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30203", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2db", "4t-30203", "30203", "30203-NTN" ], "locale_variants": {} }, { "sku": "32203", "brand": "NTN", "manufacturer_designation": "NTN 32203", "series": "32200-series", "type": "tapered_roller", "d_mm": 17, "D_mm": 40, "B_mm": 17.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 30.5, "static_load_kN": 28.3, "limiting_speed_rpm": 9900, "max_rpm": 9900, "speed_oil_rpm": 13000, "weight_g": 102, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32203 belongs to the NTN metric 4T tapered roller range (heavy-section 32200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32203 resolves to 17 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32203, since running clearance is set during assembly. Selection: C 30.5 kN against C0 28.3 kN gives a C0/C ratio of 0.93 for the 17 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 32203 washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "scooter and light-powersport wheel and gear positions", "small conveyor pulley shafts", "steering-knuckle and kingpin positions", "small automotive wheel hubs and trailer axles" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 17 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 32203 pair with a dial indicator rather than by feel.", "The heavy-section 32200 family at 17 mm bore (40×17.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 13,000 r/min oil ceiling.", "ISO 355 makes the 17×40 mm envelope interchangeable but not the ratings: NTN prints 30.5/28.3 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 17 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 17 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 30.5/28.3 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32203 (ISO 355 2DD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32203?", "a": "32203 is a metric 4T tapered roller bearing to ISO 355: 17 mm bore, 40 mm outside diameter and 17.25 mm assembled width T (0.669 × 1.575 × 0.679 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 30.5 kN, C0 28.3 kN (2203E prints no Pu for this size), grease limiting speed 9,900 r/min, oil speed 13,000 r/min, mass about 102 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32203?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32203); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32203 designation encode the 17 mm bore and what is 2DD?", "a": "last two digits 03 are the ISO bore code, ×5 = 17 mm (codes 00–03 use the 10/12/15/17 exception table). The 40 mm OD and 17.25 mm assembled T follow the ISO 355 dimension-series plan. 2DD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32203 list two speeds, 9,900 and 13,000 r/min?", "a": "The lower figure, 9,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32203 at 13,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32203 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32203", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2dd", "4t-32203", "32203" ], "locale_variants": {} }, { "sku": "30303-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30303", "series": "30300-series", "type": "tapered_roller", "d_mm": 17, "D_mm": 47, "B_mm": 15.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 32, "static_load_kN": 26.3, "limiting_speed_rpm": 9000, "max_rpm": 9000, "speed_oil_rpm": 12000, "weight_g": 132, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30303 in the large-OD 30300 family with the steeper contact angle: 17 mm bore, 47 mm cup OD, 15.25 mm T, with a grease limiting speed of 9,000 r/min and an oil-lubricated ceiling of 12,000 r/min. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30303 resolves to 17 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The printed contact-angle geometry gives the large-OD 30300 family with the steeper contact angle its characteristic load split — at 32/26.3 kN (C/C0) the static rating is about 0.82× C, typical of tapered bearings proportioned for heavy combined duty. The two speed columns differ by a factor of .75 (grease/limiting 9,000 vs oil 12,000 r/min); heat generation at the cone rib decides which lubrication a real 30303 arrangement can sustain. Fillet radii must clear the ring chamfers of the 47 mm cup and 17 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "scooter and light-powersport wheel and gear positions", "small conveyor pulley shafts", "steering-knuckle and kingpin positions", "small automotive wheel hubs and trailer axles" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 17 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 30303 pair with a dial indicator rather than by feel.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 17 mm bore; do not swap to the lighter family without re-checking the 9,000 r/min grease limit and the thrust load split.", "Open 30303 units have no seals: a wheel-hub or gearbox application needs external sealing or the 9,000 r/min grease figure is meaningless once water reaches the cone rib.", "The 15.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30303 or the ring will bottom out on the radius instead of the shoulder face.", "Minimum load matters at high speed: an unloaded 30303 at a large fraction of 9,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 32/26.3 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30303 (ISO 355 2FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30303?", "a": "30303 is a metric 4T tapered roller bearing to ISO 355: 17 mm bore, 47 mm outside diameter and 15.25 mm assembled width T (0.669 × 1.85 × 0.6 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 32 kN, C0 26.3 kN (2203E prints no Pu for this size), grease limiting speed 9,000 r/min, oil speed 12,000 r/min, mass about 132 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30303?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30303); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30303 designation encode the 17 mm bore and what is 2FB?", "a": "last two digits 03 are the ISO bore code, ×5 = 17 mm (codes 00–03 use the 10/12/15/17 exception table). The 47 mm OD and 15.25 mm assembled T follow the ISO 355 dimension-series plan. 2FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30303 list two speeds, 9,000 and 12,000 r/min?", "a": "The lower figure, 9,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30303 at 12,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30303 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30303", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fb", "4t-30303", "30303", "30303-NTN" ], "locale_variants": {} }, { "sku": "32004X", "brand": "NTN", "manufacturer_designation": "NTN 32004X", "series": "32000-series", "type": "tapered_roller", "d_mm": 20, "D_mm": 42, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 27.6, "static_load_kN": 27.9, "limiting_speed_rpm": 9500, "max_rpm": 9500, "speed_oil_rpm": 13000, "weight_g": 97, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 20 mm bore tapered roller position as 32004X: one cone assembly, one cup, line-contact rollers and a steel cage, rated 27.6 kN basic dynamic and 27.9 kN static on the low-section 32000 family tuned for low friction. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3CC, which is the maker-neutral cross-reference for the 20×42 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN grades 4T metric bearings as open bearings without integral seals; at 20 mm bore the application supplies the seals and the grease fill or oil supply to the 3CC ISO 355 assembly. 2203E does not print a Pu fatigue load limit for 32004X; life work for this size uses the 27.6/27.9 kN C/C0 pair directly. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32004X arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "agricultural implement hubs and ground-tool drives", "small gearbox input shafts with combined load", "scooter and light-powersport wheel and gear positions", "small conveyor pulley shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 20 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 32004X pair with a dial indicator rather than by feel.", "The thin 15 mm section of 32004X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 20 mm bore smears the roller ends against the rib.", "The 11.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32004X or the ring will bottom out on the radius instead of the shoulder face.", "Do not confuse T (15 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 11.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32004X or the ring will bottom out on the radius instead of the shoulder face.", "The 27.6/27.9 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32004X (ISO 355 3CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32004X?", "a": "32004X is a metric 4T tapered roller bearing to ISO 355: 20 mm bore, 42 mm outside diameter and 15 mm assembled width T (0.787 × 1.654 × 0.591 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 27.6 kN, C0 27.9 kN (2203E prints no Pu for this size), grease limiting speed 9,500 r/min, oil speed 13,000 r/min, mass about 97 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32004X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32004X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32004X designation encode the 20 mm bore and what is 3CC?", "a": "last two digits 04 are the ISO bore code, ×5 = 20 mm (codes 00–03 use the 10/12/15/17 exception table). The 42 mm OD and 15 mm assembled T follow the ISO 355 dimension-series plan. 3CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32004X list two speeds, 9,500 and 13,000 r/min?", "a": "The lower figure, 9,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32004X at 13,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32004X mean?", "a": "Suffix reading on 32004X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32004X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32004x", "3cc", "4t-32004x", "32004X" ], "locale_variants": {} }, { "sku": "30204-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30204", "series": "30200-series", "type": "tapered_roller", "d_mm": 20, "D_mm": 47, "B_mm": 15.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 31, "static_load_kN": 28.7, "limiting_speed_rpm": 8800, "max_rpm": 8800, "speed_oil_rpm": 12000, "weight_g": 124, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30204 in the standard-section 30200 family: 20 mm bore, 47 mm cup OD, 15.25 mm T, with a grease limiting speed of 8,800 r/min and an oil-lubricated ceiling of 12,000 r/min. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2DB, which is the maker-neutral cross-reference for the 20×47 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN grades 4T metric bearings as open bearings without integral seals; at 20 mm bore the application supplies the seals and the grease fill or oil supply to the 2DB ISO 355 assembly. Grease relubrication at 8,800 r/min limiting speed targets the rib contact; if the drive needs 12,000 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Fillet radii must clear the ring chamfers of the 47 mm cup and 20 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "steering-knuckle and kingpin positions", "small automotive wheel hubs and trailer axles", "light-vehicle differential and pinion shafts", "agricultural implement hubs and ground-tool drives" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 20 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 30204 pair with a dial indicator rather than by feel.", "The standard-section 30200 family at 20 mm bore (47×15.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 12,000 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 15.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 30204 units have no seals: a wheel-hub or gearbox application needs external sealing or the 8,800 r/min grease figure is meaningless once water reaches the cone rib.", "The 13.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30204 or the ring will bottom out on the radius instead of the shoulder face.", "The 31/28.7 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30204 (ISO 355 2DB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30204?", "a": "30204 is a metric 4T tapered roller bearing to ISO 355: 20 mm bore, 47 mm outside diameter and 15.25 mm assembled width T (0.787 × 1.85 × 0.6 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 31 kN, C0 28.7 kN (2203E prints no Pu for this size), grease limiting speed 8,800 r/min, oil speed 12,000 r/min, mass about 124 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30204?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30204); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30204 designation encode the 20 mm bore and what is 2DB?", "a": "last two digits 04 are the ISO bore code, ×5 = 20 mm (codes 00–03 use the 10/12/15/17 exception table). The 47 mm OD and 15.25 mm assembled T follow the ISO 355 dimension-series plan. 2DB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30204 list two speeds, 8,800 and 12,000 r/min?", "a": "The lower figure, 8,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30204 at 12,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30204 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30204", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2db", "4t-30204", "30204", "30204-NTN" ], "locale_variants": {} }, { "sku": "32204-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32204", "series": "32200-series", "type": "tapered_roller", "d_mm": 20, "D_mm": 47, "B_mm": 19.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 40.5, "static_load_kN": 39.5, "limiting_speed_rpm": 8800, "max_rpm": 8800, "speed_oil_rpm": 12000, "weight_g": 161, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32204 denotes the heavy-section 32200 family of metric tapered roller bearings, 20 mm bore, 47 mm outside diameter and 19.25 mm assembled width T (0.787 × 1.85 × 0.758 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the heavy-section 32200 family and a bore code resolving to 20 mm; 47 mm OD and 19.25 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. With no letter after the number, 32204 is the basic open 4T execution: steel cage, normal adjustment, no seal or special internal-design suffix in the order code. 2203E does not print a Pu fatigue load limit for 32204; life work for this size uses the 40.5/39.5 kN C/C0 pair directly. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32204 arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "steering-knuckle and kingpin positions", "small automotive wheel hubs and trailer axles", "light-vehicle differential and pinion shafts", "agricultural implement hubs and ground-tool drives" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 20 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 32204 pair with a dial indicator rather than by feel.", "The heavy-section 32200 family at 20 mm bore (47×19.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 12,000 r/min oil ceiling.", "Grease packs must leave free volume in the 19.25 mm-wide set; over-greasing a paired bearing churning at the 12,000 r/min oil-band speed raises temperature and destroys the preload setting.", "Replacing one half of an adjusted pair without resetting end play negates the 19.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ISO 355 makes the 20×47 mm envelope interchangeable but not the ratings: NTN prints 40.5/39.5 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 40.5/39.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32204 (ISO 355 2DD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32204?", "a": "32204 is a metric 4T tapered roller bearing to ISO 355: 20 mm bore, 47 mm outside diameter and 19.25 mm assembled width T (0.787 × 1.85 × 0.758 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 40.5 kN, C0 39.5 kN (2203E prints no Pu for this size), grease limiting speed 8,800 r/min, oil speed 12,000 r/min, mass about 161 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32204?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32204); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32204 designation encode the 20 mm bore and what is 2DD?", "a": "last two digits 04 are the ISO bore code, ×5 = 20 mm (codes 00–03 use the 10/12/15/17 exception table). The 47 mm OD and 19.25 mm assembled T follow the ISO 355 dimension-series plan. 2DD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32204 list two speeds, 8,800 and 12,000 r/min?", "a": "The lower figure, 8,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32204 at 12,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32204 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32204", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2dd", "4t-32204", "32204", "32204-NTN" ], "locale_variants": {} }, { "sku": "30304A", "brand": "NTN", "manufacturer_designation": "NTN 30304A", "series": "30300-series", "type": "tapered_roller", "d_mm": 20, "D_mm": 52, "B_mm": 16.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 39, "static_load_kN": 34, "limiting_speed_rpm": 8000, "max_rpm": 8000, "speed_oil_rpm": 11000, "weight_g": 172, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30304A belongs to the NTN metric 4T tapered roller range (large-OD 30300 family with the steeper contact angle); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2FB, which is the maker-neutral cross-reference for the 20×52 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 30304A, since running clearance is set during assembly. Speed planning uses both catalogue columns: grease 8,000 r/min is the cage/rib mechanical ceiling for 30304A, oil 11,000 r/min is available with circulating oil — a 3,000 r/min margin at this size. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 30304A; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "small conveyor pulley shafts", "steering-knuckle and kingpin positions", "small automotive wheel hubs and trailer axles", "light-vehicle differential and pinion shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 20 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 30304A pair with a dial indicator rather than by feel.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 20 mm bore; do not swap to the lighter family without re-checking the 8,000 r/min grease limit and the thrust load split.", "ISO 355 makes the 20×52 mm envelope interchangeable but not the ratings: NTN prints 39/34 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Open 30304A units have no seals: a wheel-hub or gearbox application needs external sealing or the 8,000 r/min grease figure is meaningless once water reaches the cone rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 20 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 39/34 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30304A (ISO 355 2FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30304A?", "a": "30304A is a metric 4T tapered roller bearing to ISO 355: 20 mm bore, 52 mm outside diameter and 16.25 mm assembled width T (0.787 × 2.047 × 0.64 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 39 kN, C0 34 kN (2203E prints no Pu for this size), grease limiting speed 8,000 r/min, oil speed 11,000 r/min, mass about 172 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30304A?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30304A); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30304A designation encode the 20 mm bore and what is 2FB?", "a": "last two digits 04 are the ISO bore code, ×5 = 20 mm (codes 00–03 use the 10/12/15/17 exception table). The 52 mm OD and 16.25 mm assembled T follow the ISO 355 dimension-series plan. 2FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30304A list two speeds, 8,000 and 11,000 r/min?", "a": "The lower figure, 8,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30304A at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30304A mean?", "a": "Suffix reading on 30304A: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30304A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fb", "30304a", "4t-30304a", "30304A" ], "locale_variants": {} }, { "sku": "30304CA", "brand": "NTN", "manufacturer_designation": "NTN 30304CA", "series": "30300-series", "type": "tapered_roller", "d_mm": 20, "D_mm": 52, "B_mm": 16.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 34.5, "static_load_kN": 31, "limiting_speed_rpm": 7600, "max_rpm": 7600, "speed_oil_rpm": 10000, "weight_g": 170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 20 mm shaft with a thrust component, NTN lists 30304CA, a metric 4T tapered roller bearing of 34.5 kN C and 31 kN C0 inside the 52 mm OD, 16.25 mm-wide assembled set. Digit by digit, the bare number identifies the large-OD 30300 family with the steeper contact angle and a bore code resolving to 20 mm; 52 mm OD and 16.25 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 30304CA cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Catalogue mass of the 30304CA set is 170 g (0.007 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. When pairing 30304CA with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "small automotive wheel hubs and trailer axles", "light-vehicle differential and pinion shafts", "agricultural implement hubs and ground-tool drives", "small gearbox input shafts with combined load" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 20 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 30304CA pair with a dial indicator rather than by feel.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 20 mm bore; do not swap to the lighter family without re-checking the 7,600 r/min grease limit and the thrust load split.", "Do not confuse T (16.25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Open 30304CA units have no seals: a wheel-hub or gearbox application needs external sealing or the 7,600 r/min grease figure is meaningless once water reaches the cone rib.", "Do not confuse T (16.25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 34.5/31 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30304CA; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30304CA?", "a": "30304CA is a metric 4T tapered roller bearing to ISO 355: 20 mm bore, 52 mm outside diameter and 16.25 mm assembled width T (0.787 × 2.047 × 0.64 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 34.5 kN, C0 31 kN (2203E prints no Pu for this size), grease limiting speed 7,600 r/min, oil speed 10,000 r/min, mass about 170 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30304CA?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30304CA); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30304CA designation encode the 20 mm bore?", "a": "last two digits 04 are the ISO bore code, ×5 = 20 mm (codes 00–03 use the 10/12/15/17 exception table). The 52 mm OD and 16.25 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30304CA list two speeds, 7,600 and 10,000 r/min?", "a": "The lower figure, 7,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30304CA at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30304CA mean?", "a": "Suffix reading on 30304CA: the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30304CA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30304ca", "4t-30304ca", "30304CA" ], "locale_variants": {} }, { "sku": "32304-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32304", "series": "32300-series", "type": "tapered_roller", "d_mm": 20, "D_mm": 52, "B_mm": 22.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 51.5, "static_load_kN": 48.5, "limiting_speed_rpm": 8000, "max_rpm": 8000, "speed_oil_rpm": 11000, "weight_g": 242, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32304 is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 20×52 mm ISO 355 envelope, with 22.25 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2FD, which is the maker-neutral cross-reference for the 20×52 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The printed contact-angle geometry gives the extra-heavy 32300 family its characteristic load split — at 51.5/48.5 kN (C/C0) the static rating is about 0.94× C, typical of tapered bearings proportioned for heavy combined duty. The 16.0 mm section height over the 20 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. When pairing 32304 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "steering-knuckle and kingpin positions", "small automotive wheel hubs and trailer axles", "light-vehicle differential and pinion shafts", "agricultural implement hubs and ground-tool drives" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 20 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 32304 pair with a dial indicator rather than by feel.", "The extra-heavy 32300 family at 20 mm bore (52×22.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 11,000 r/min oil ceiling.", "ISO 355 makes the 20×52 mm envelope interchangeable but not the ratings: NTN prints 51.5/48.5 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Open 32304 units have no seals: a wheel-hub or gearbox application needs external sealing or the 8,000 r/min grease figure is meaningless once water reaches the cone rib.", "Minimum load matters at high speed: an unloaded 32304 at a large fraction of 8,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 51.5/48.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32304 (ISO 355 2FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32304?", "a": "32304 is a metric 4T tapered roller bearing to ISO 355: 20 mm bore, 52 mm outside diameter and 22.25 mm assembled width T (0.787 × 2.047 × 0.876 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 51.5 kN, C0 48.5 kN (2203E prints no Pu for this size), grease limiting speed 8,000 r/min, oil speed 11,000 r/min, mass about 242 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32304?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32304); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32304 designation encode the 20 mm bore and what is 2FD?", "a": "last two digits 04 are the ISO bore code, ×5 = 20 mm (codes 00–03 use the 10/12/15/17 exception table). The 52 mm OD and 22.25 mm assembled T follow the ISO 355 dimension-series plan. 2FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32304 list two speeds, 8,000 and 11,000 r/min?", "a": "The lower figure, 8,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32304 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32304 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32304", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fd", "4t-32304", "32304", "32304-NTN" ], "locale_variants": {} }, { "sku": "320-22X", "brand": "NTN", "manufacturer_designation": "NTN 320/22X", "series": "32000-series", "type": "tapered_roller", "d_mm": 22, "D_mm": 44, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 30, "static_load_kN": 31.5, "limiting_speed_rpm": 8900, "max_rpm": 8900, "speed_oil_rpm": 12000, "weight_g": 105, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "320/22X belongs to the NTN metric 4T tapered roller range (low-section 32000 family tuned for low friction); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. The 22 mm bore is printed directly after the slash in the slash-size convention under the ISO 355 numbering; the 15 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Suffix reading on 320/22X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles. 2203E does not print a Pu fatigue load limit for 320/22X; life work for this size uses the 30/31.5 kN C/C0 pair directly. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 320/22X arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "small automotive wheel hubs and trailer axles", "light-vehicle differential and pinion shafts", "agricultural implement hubs and ground-tool drives", "small gearbox input shafts with combined load" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 22 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 320/22X pair with a dial indicator rather than by feel.", "The thin 15 mm section of 320/22X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 22 mm bore smears the roller ends against the rib.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 320/22X by size alone can deliver the wrong contact-angle execution for a pinion position.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 320/22X by size alone can deliver the wrong contact-angle execution for a pinion position.", "ISO 355 makes the 22×44 mm envelope interchangeable but not the ratings: NTN prints 30/31.5 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 30/31.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 320/22X (ISO 355 3CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 320/22X?", "a": "320/22X is a metric 4T tapered roller bearing to ISO 355: 22 mm bore, 44 mm outside diameter and 15 mm assembled width T (0.866 × 1.732 × 0.591 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 30 kN, C0 31.5 kN (2203E prints no Pu for this size), grease limiting speed 8,900 r/min, oil speed 12,000 r/min, mass about 105 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 320/22X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (320/22X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 320/22X designation encode the 22 mm bore and what is 3CC?", "a": "22 mm bore is printed directly after the slash in the slash-size convention. The 44 mm OD and 15 mm assembled T follow the ISO 355 dimension-series plan. 3CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 320/22X list two speeds, 8,900 and 12,000 r/min?", "a": "The lower figure, 8,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 320/22X at 12,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 320/22X mean?", "a": "Suffix reading on 320/22X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "320-22", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "320-28", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "320-32", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "320-22x", "3cc", "4t-320-22x", "320-22X" ], "locale_variants": {} }, { "sku": "32005X", "brand": "NTN", "manufacturer_designation": "NTN 32005X", "series": "32000-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 47, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 31, "static_load_kN": 33.5, "limiting_speed_rpm": 7900, "max_rpm": 7900, "speed_oil_rpm": 11000, "weight_g": 113, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 25 mm shaft with a thrust component, NTN lists 32005X, a metric 4T tapered roller bearing of 31 kN C and 33.5 kN C0 inside the 47 mm OD, 15 mm-wide assembled set. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32005X resolves to 25 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The 11.0 mm radial section carries the roller complement across the 25–47 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Catalogue mass of the 32005X set is 113 g (0.004 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 32005X; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "small gearbox input shafts with combined load", "scooter and light-powersport wheel and gear positions", "small conveyor pulley shafts", "steering-knuckle and kingpin positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 25 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 32005X pair with a dial indicator rather than by feel.", "The thin 15 mm section of 32005X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 25 mm bore smears the roller ends against the rib.", "ISO 355 makes the 25×47 mm envelope interchangeable but not the ratings: NTN prints 31/33.5 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "ISO 355 makes the 25×47 mm envelope interchangeable but not the ratings: NTN prints 31/33.5 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32005X by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 31/33.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32005X (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32005X?", "a": "32005X is a metric 4T tapered roller bearing to ISO 355: 25 mm bore, 47 mm outside diameter and 15 mm assembled width T (0.984 × 1.85 × 0.591 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 31 kN, C0 33.5 kN (2203E prints no Pu for this size), grease limiting speed 7,900 r/min, oil speed 11,000 r/min, mass about 113 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32005X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32005X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32005X designation encode the 25 mm bore and what is 4CC?", "a": "last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table). The 47 mm OD and 15 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32005X list two speeds, 7,900 and 11,000 r/min?", "a": "The lower figure, 7,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32005X at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32005X mean?", "a": "Suffix reading on 32005X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32005X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32005x", "4cc", "4t-32005x", "32005X" ], "locale_variants": {} }, { "sku": "33005", "brand": "NTN", "manufacturer_designation": "NTN 33005", "series": "33000-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 47, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 36, "static_load_kN": 40.5, "limiting_speed_rpm": 8000, "max_rpm": 8000, "speed_oil_rpm": 11000, "weight_g": 130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 25 mm bore tapered roller position as 33005: one cone assembly, one cup, line-contact rollers and a steel cage, rated 36 kN basic dynamic and 40.5 kN static on the slim 33000 family. The last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 17 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Selection: C 36 kN against C0 40.5 kN gives a C0/C ratio of 1.13 for the 25 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 33005; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "small gearbox input shafts with combined load", "scooter and light-powersport wheel and gear positions", "small conveyor pulley shafts", "steering-knuckle and kingpin positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 25 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 33005 pair with a dial indicator rather than by feel.", "The thin 17 mm section of 33005 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 25 mm bore smears the roller ends against the rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 25 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Minimum load matters at high speed: an unloaded 33005 at a large fraction of 8,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Replacing one half of an adjusted pair without resetting end play negates the 17 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 36/40.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33005 (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33005?", "a": "33005 is a metric 4T tapered roller bearing to ISO 355: 25 mm bore, 47 mm outside diameter and 17 mm assembled width T (0.984 × 1.85 × 0.669 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 36 kN, C0 40.5 kN (2203E prints no Pu for this size), grease limiting speed 8,000 r/min, oil speed 11,000 r/min, mass about 130 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33005?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33005); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33005 designation encode the 25 mm bore and what is 2CE?", "a": "last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table). The 47 mm OD and 17 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33005 list two speeds, 8,000 and 11,000 r/min?", "a": "The lower figure, 8,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33005 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33005 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33005", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "4t-33005", "33005" ], "locale_variants": {} }, { "sku": "30205-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30205", "series": "30200-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 52, "B_mm": 16.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 35, "static_load_kN": 34, "limiting_speed_rpm": 7300, "max_rpm": 7300, "speed_oil_rpm": 9800, "weight_g": 155, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30205 is the NTN 4T catalogue entry for a 25×52×16.25 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30205 resolves to 25 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The 13.5 mm radial section carries the roller complement across the 25–52 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The 13.5 mm section height over the 25 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Mount the 25 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30205.", "applications": [ "light-vehicle differential and pinion shafts", "agricultural implement hubs and ground-tool drives", "small gearbox input shafts with combined load", "scooter and light-powersport wheel and gear positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 25 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 30205 pair with a dial indicator rather than by feel.", "The standard-section 30200 family at 25 mm bore (52×16.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 9,800 r/min oil ceiling.", "The 13.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30205 or the ring will bottom out on the radius instead of the shoulder face.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 25 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30205 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 35/34 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30205 (ISO 355 3CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30205?", "a": "30205 is a metric 4T tapered roller bearing to ISO 355: 25 mm bore, 52 mm outside diameter and 16.25 mm assembled width T (0.984 × 2.047 × 0.64 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 35 kN, C0 34 kN (2203E prints no Pu for this size), grease limiting speed 7,300 r/min, oil speed 9,800 r/min, mass about 155 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30205?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30205); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30205 designation encode the 25 mm bore and what is 3CC?", "a": "last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table). The 52 mm OD and 16.25 mm assembled T follow the ISO 355 dimension-series plan. 3CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30205 list two speeds, 7,300 and 9,800 r/min?", "a": "The lower figure, 7,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30205 at 9,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30205 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30205", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3cc", "4t-30205", "30205", "30205-NTN" ], "locale_variants": {} }, { "sku": "32205-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32205", "series": "32200-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 52, "B_mm": 19.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 46.5, "static_load_kN": 47, "limiting_speed_rpm": 7300, "max_rpm": 7300, "speed_oil_rpm": 9800, "weight_g": 187, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32205 is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 25×52 mm ISO 355 envelope, with 19.25 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32205 by the metric ISO 355 number (ISO series abbreviation 2CD): 25 mm bore, 52 mm OD. NTN grades 4T metric bearings as open bearings without integral seals; at 25 mm bore the application supplies the seals and the grease fill or oil supply to the 2CD ISO 355 assembly. Speed planning uses both catalogue columns: grease 7,300 r/min is the cage/rib mechanical ceiling for 32205, oil 9,800 r/min is available with circulating oil — a 2,500 r/min margin at this size. When pairing 32205 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "light-vehicle differential and pinion shafts", "agricultural implement hubs and ground-tool drives", "small gearbox input shafts with combined load", "scooter and light-powersport wheel and gear positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 25 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 32205 pair with a dial indicator rather than by feel.", "The heavy-section 32200 family at 25 mm bore (52×19.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 9,800 r/min oil ceiling.", "Open 32205 units have no seals: a wheel-hub or gearbox application needs external sealing or the 7,300 r/min grease figure is meaningless once water reaches the cone rib.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32205 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 13.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32205 or the ring will bottom out on the radius instead of the shoulder face.", "The 46.5/47 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32205 (ISO 355 2CD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32205?", "a": "32205 is a metric 4T tapered roller bearing to ISO 355: 25 mm bore, 52 mm outside diameter and 19.25 mm assembled width T (0.984 × 2.047 × 0.758 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 46.5 kN, C0 47 kN (2203E prints no Pu for this size), grease limiting speed 7,300 r/min, oil speed 9,800 r/min, mass about 187 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32205?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32205); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32205 designation encode the 25 mm bore and what is 2CD?", "a": "last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table). The 52 mm OD and 19.25 mm assembled T follow the ISO 355 dimension-series plan. 2CD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32205 list two speeds, 7,300 and 9,800 r/min?", "a": "The lower figure, 7,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32205 at 9,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32205 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32205", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32205-SKF", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2cd", "4t-32205", "32205", "32205-NTN" ], "locale_variants": {} }, { "sku": "32205C", "brand": "NTN", "manufacturer_designation": "NTN 32205C", "series": "32200-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 52, "B_mm": 19.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 42.5, "static_load_kN": 46.5, "limiting_speed_rpm": 7100, "max_rpm": 7100, "speed_oil_rpm": 9400, "weight_g": 192, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32205C denotes the heavy-section 32200 family of metric tapered roller bearings, 25 mm bore, 52 mm outside diameter and 19.25 mm assembled width T (0.984 × 2.047 × 0.758 in) to the ISO 355 boundary plan. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32205C resolves to 25 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32205C, not only the raceway. Grease relubrication at 7,100 r/min limiting speed targets the rib contact; if the drive needs 9,400 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Mount the 25 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32205C.", "applications": [ "agricultural implement hubs and ground-tool drives", "small gearbox input shafts with combined load", "scooter and light-powersport wheel and gear positions", "small conveyor pulley shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 25 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 32205C pair with a dial indicator rather than by feel.", "The heavy-section 32200 family at 25 mm bore (52×19.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 9,400 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 32205C at a large fraction of 7,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 25 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 25 mm shoulder geometry, because retrofitting flips the cups.", "The 42.5/46.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32205C (ISO 355 5CD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32205C?", "a": "32205C is a metric 4T tapered roller bearing to ISO 355: 25 mm bore, 52 mm outside diameter and 19.25 mm assembled width T (0.984 × 2.047 × 0.758 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 42.5 kN, C0 46.5 kN (2203E prints no Pu for this size), grease limiting speed 7,100 r/min, oil speed 9,400 r/min, mass about 192 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32205C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32205C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32205C designation encode the 25 mm bore and what is 5CD?", "a": "last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table). The 52 mm OD and 19.25 mm assembled T follow the ISO 355 dimension-series plan. 5CD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32205C list two speeds, 7,100 and 9,400 r/min?", "a": "The lower figure, 7,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32205C at 9,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32205C mean?", "a": "Suffix reading on 32205C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32205C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32205c", "4t-32205c", "5cd", "32205C" ], "locale_variants": {} }, { "sku": "33205-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33205", "series": "33200-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 52, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52.5, "static_load_kN": 57.5, "limiting_speed_rpm": 7300, "max_rpm": 7300, "speed_oil_rpm": 9800, "weight_g": 219, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 25 mm bore tapered roller position as 33205: one cone assembly, one cup, line-contact rollers and a steel cage, rated 52.5 kN basic dynamic and 57.5 kN static on the medium-wide 33200 family. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 33205 resolves to 25 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The printed contact-angle geometry gives the medium-wide 33200 family its characteristic load split — at 52.5/57.5 kN (C/C0) the static rating is about 1.10× C, typical of tapered bearings proportioned for heavy combined duty. Speed planning uses both catalogue columns: grease 7,300 r/min is the cage/rib mechanical ceiling for 33205, oil 9,800 r/min is available with circulating oil — a 2,500 r/min margin at this size. Mount the 25 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 33205.", "applications": [ "agricultural implement hubs and ground-tool drives", "small gearbox input shafts with combined load", "scooter and light-powersport wheel and gear positions", "small conveyor pulley shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 25 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 33205 pair with a dial indicator rather than by feel.", "The medium-wide 33200 family at 25 mm bore (52×22 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 9,800 r/min oil ceiling.", "Grease packs must leave free volume in the 22 mm-wide set; over-greasing a paired bearing churning at the 9,800 r/min oil-band speed raises temperature and destroys the preload setting.", "Grease packs must leave free volume in the 22 mm-wide set; over-greasing a paired bearing churning at the 9,800 r/min oil-band speed raises temperature and destroys the preload setting.", "Minimum load matters at high speed: an unloaded 33205 at a large fraction of 7,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 52.5/57.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33205 (ISO 355 2DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33205?", "a": "33205 is a metric 4T tapered roller bearing to ISO 355: 25 mm bore, 52 mm outside diameter and 22 mm assembled width T (0.984 × 2.047 × 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52.5 kN, C0 57.5 kN (2203E prints no Pu for this size), grease limiting speed 7,300 r/min, oil speed 9,800 r/min, mass about 219 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33205?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33205); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33205 designation encode the 25 mm bore and what is 2DE?", "a": "last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table). The 52 mm OD and 22 mm assembled T follow the ISO 355 dimension-series plan. 2DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33205 list two speeds, 7,300 and 9,800 r/min?", "a": "The lower figure, 7,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33205 at 9,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33205 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33205", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2de", "4t-33205", "33205", "33205-NTN" ], "locale_variants": {} }, { "sku": "30305-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30305", "series": "30300-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 62, "B_mm": 18.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 54, "static_load_kN": 47.5, "limiting_speed_rpm": 6700, "max_rpm": 6700, "speed_oil_rpm": 8900, "weight_g": 268, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30305 in the large-OD 30300 family with the steeper contact angle: 25 mm bore, 62 mm cup OD, 18.25 mm T, with a grease limiting speed of 6,700 r/min and an oil-lubricated ceiling of 8,900 r/min. Digit by digit, the bare number identifies the large-OD 30300 family with the steeper contact angle and a bore code resolving to 25 mm; 62 mm OD and 18.25 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN grades 4T metric bearings as open bearings without integral seals; at 25 mm bore the application supplies the seals and the grease fill or oil supply to the 2FB ISO 355 assembly. The 2.2 kN-per-mm-bore capacity figure for 30305 summarises the 54 kN rating over 25 mm bore; use it to sanity-check an interchange candidate before swapping brands. Mount the 25 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30305.", "applications": [ "light-vehicle differential and pinion shafts", "agricultural implement hubs and ground-tool drives", "small gearbox input shafts with combined load", "scooter and light-powersport wheel and gear positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 25 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 30305 pair with a dial indicator rather than by feel.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 25 mm bore; do not swap to the lighter family without re-checking the 6,700 r/min grease limit and the thrust load split.", "Replacing one half of an adjusted pair without resetting end play negates the 18.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never fit the 25 mm cone by hammering the 62 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 18.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30305 or the ring will bottom out on the radius instead of the shoulder face.", "The 54/47.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30305 (ISO 355 2FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30305?", "a": "30305 is a metric 4T tapered roller bearing to ISO 355: 25 mm bore, 62 mm outside diameter and 18.25 mm assembled width T (0.984 × 2.441 × 0.719 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 54 kN, C0 47.5 kN (2203E prints no Pu for this size), grease limiting speed 6,700 r/min, oil speed 8,900 r/min, mass about 268 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30305?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30305); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30305 designation encode the 25 mm bore and what is 2FB?", "a": "last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 18.25 mm assembled T follow the ISO 355 dimension-series plan. 2FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30305 list two speeds, 6,700 and 8,900 r/min?", "a": "The lower figure, 6,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30305 at 8,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30305 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30305", "equiv_brand": "SKF", "level": "partial", "note": "Same 25×62×18.25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fb", "4t-30305", "30305", "30305-NTN" ], "locale_variants": {} }, { "sku": "30305C", "brand": "NTN", "manufacturer_designation": "NTN 30305C", "series": "30300-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 62, "B_mm": 18.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 46, "static_load_kN": 41.5, "limiting_speed_rpm": 6400, "max_rpm": 6400, "speed_oil_rpm": 8500, "weight_g": 264, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30305C in the large-OD 30300 family with the steeper contact angle: 25 mm bore, 62 mm cup OD, 18.25 mm T, with a grease limiting speed of 6,400 r/min and an oil-lubricated ceiling of 8,500 r/min. The last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 18.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 30305C, not only the raceway. Imperial cross-check for the drawing: 25×62×18.25 mm is 0.984 × 2.441 × 0.719 in; ISO 355 makes the envelope interchangeable but C/C0, 46/41.5 kN, is NTN-specific. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 30305C arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "small gearbox input shafts with combined load", "scooter and light-powersport wheel and gear positions", "small conveyor pulley shafts", "steering-knuckle and kingpin positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 25 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 30305C pair with a dial indicator rather than by feel.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 25 mm bore; do not swap to the lighter family without re-checking the 6,400 r/min grease limit and the thrust load split.", "Do not confuse T (18.25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "ISO 355 makes the 25×62 mm envelope interchangeable but not the ratings: NTN prints 46/41.5 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 25 mm shoulder geometry, because retrofitting flips the cups.", "The 46/41.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30305C; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30305C?", "a": "30305C is a metric 4T tapered roller bearing to ISO 355: 25 mm bore, 62 mm outside diameter and 18.25 mm assembled width T (0.984 × 2.441 × 0.719 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 46 kN, C0 41.5 kN (2203E prints no Pu for this size), grease limiting speed 6,400 r/min, oil speed 8,500 r/min, mass about 264 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30305C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30305C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30305C designation encode the 25 mm bore?", "a": "last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 18.25 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30305C list two speeds, 6,400 and 8,500 r/min?", "a": "The lower figure, 6,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30305C at 8,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30305C mean?", "a": "Suffix reading on 30305C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30305C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30305c", "4t-30305c", "30305C" ], "locale_variants": {} }, { "sku": "30305D", "brand": "NTN", "manufacturer_designation": "NTN 30305D", "series": "30300-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 62, "B_mm": 18.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 45, "static_load_kN": 43.5, "limiting_speed_rpm": 5900, "max_rpm": 5900, "speed_oil_rpm": 7800, "weight_g": 266, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 25 mm shaft with a thrust component, NTN lists 30305D, a metric 4T tapered roller bearing of 45 kN C and 43.5 kN C0 inside the 62 mm OD, 18.25 mm-wide assembled set. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 7FB, which is the maker-neutral cross-reference for the 25×62 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Grease relubrication at 5,900 r/min limiting speed targets the rib contact; if the drive needs 7,800 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Fillet radii must clear the ring chamfers of the 62 mm cup and 25 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "small conveyor pulley shafts", "steering-knuckle and kingpin positions", "small automotive wheel hubs and trailer axles", "light-vehicle differential and pinion shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 25 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 30305D pair with a dial indicator rather than by feel.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 25 mm bore; do not swap to the lighter family without re-checking the 5,900 r/min grease limit and the thrust load split.", "The 18.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30305D or the ring will bottom out on the radius instead of the shoulder face.", "Do not confuse T (18.25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 18.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 45/43.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30305D (ISO 355 7FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30305D?", "a": "30305D is a metric 4T tapered roller bearing to ISO 355: 25 mm bore, 62 mm outside diameter and 18.25 mm assembled width T (0.984 × 2.441 × 0.719 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 45 kN, C0 43.5 kN (2203E prints no Pu for this size), grease limiting speed 5,900 r/min, oil speed 7,800 r/min, mass about 266 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30305D?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30305D); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30305D designation encode the 25 mm bore and what is 7FB?", "a": "last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 18.25 mm assembled T follow the ISO 355 dimension-series plan. 7FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30305D list two speeds, 5,900 and 7,800 r/min?", "a": "The lower figure, 5,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30305D at 7,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30305D mean?", "a": "Suffix reading on 30305D: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30305D", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30305d", "4t-30305d", "7fb", "30305D" ], "locale_variants": {} }, { "sku": "32305-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32305", "series": "32300-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 62, "B_mm": 25.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 68, "static_load_kN": 64.5, "limiting_speed_rpm": 6700, "max_rpm": 6700, "speed_oil_rpm": 8900, "weight_g": 377, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32305 denotes the extra-heavy 32300 family of metric tapered roller bearings, 25 mm bore, 62 mm outside diameter and 25.25 mm assembled width T (0.984 × 2.441 × 0.994 in) to the ISO 355 boundary plan. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32305 resolves to 25 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. With no letter after the number, 32305 is the basic open 4T execution: steel cage, normal adjustment, no seal or special internal-design suffix in the order code. Catalogue mass of the 32305 set is 377 g (0.015 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. When pairing 32305 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "light-vehicle differential and pinion shafts", "agricultural implement hubs and ground-tool drives", "small gearbox input shafts with combined load", "scooter and light-powersport wheel and gear positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 25 mm bore the thin section and small rollers are adjustment-sensitive: a quarter-turn of the locknut moves end play by more than on large bearings, so set the 32305 pair with a dial indicator rather than by feel.", "The extra-heavy 32300 family at 25 mm bore (62×25.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 8,900 r/min oil ceiling.", "Grease packs must leave free volume in the 25.25 mm-wide set; over-greasing a paired bearing churning at the 8,900 r/min oil-band speed raises temperature and destroys the preload setting.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 25 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "ISO 355 makes the 25×62 mm envelope interchangeable but not the ratings: NTN prints 68/64.5 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 68/64.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32305 (ISO 355 2FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32305?", "a": "32305 is a metric 4T tapered roller bearing to ISO 355: 25 mm bore, 62 mm outside diameter and 25.25 mm assembled width T (0.984 × 2.441 × 0.994 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 68 kN, C0 64.5 kN (2203E prints no Pu for this size), grease limiting speed 6,700 r/min, oil speed 8,900 r/min, mass about 377 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32305?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32305); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32305 designation encode the 25 mm bore and what is 2FD?", "a": "last two digits 05 are the ISO bore code, ×5 = 25 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 25.25 mm assembled T follow the ISO 355 dimension-series plan. 2FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32305 list two speeds, 6,700 and 8,900 r/min?", "a": "The lower figure, 6,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32305 at 8,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32305 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32305", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fd", "4t-32305", "32305", "32305-NTN" ], "locale_variants": {} }, { "sku": "320-28X", "brand": "NTN", "manufacturer_designation": "NTN 320/28X", "series": "32000-series", "type": "tapered_roller", "d_mm": 28, "D_mm": 52, "B_mm": 16, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 37, "static_load_kN": 40.5, "limiting_speed_rpm": 7300, "max_rpm": 7300, "speed_oil_rpm": 9700, "weight_g": 146, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "320/28X is the NTN 4T catalogue entry for a 28×52×16 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Digit by digit, the bare number identifies the low-section 32000 family tuned for low friction and a bore code resolving to 28 mm; 52 mm OD and 16 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 320/28X, since running clearance is set during assembly. The two speed columns differ by a factor of .75 (grease/limiting 7,300 vs oil 9,700 r/min); heat generation at the cone rib decides which lubrication a real 320/28X arrangement can sustain. Fillet radii must clear the ring chamfers of the 52 mm cup and 28 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 28 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 320/28X.", "The thin 16 mm section of 320/28X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 28 mm bore smears the roller ends against the rib.", "Open 320/28X units have no seals: a wheel-hub or gearbox application needs external sealing or the 7,300 r/min grease figure is meaningless once water reaches the cone rib.", "ISO 355 makes the 28×52 mm envelope interchangeable but not the ratings: NTN prints 37/40.5 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 28 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 37/40.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 320/28X (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 320/28X?", "a": "320/28X is a metric 4T tapered roller bearing to ISO 355: 28 mm bore, 52 mm outside diameter and 16 mm assembled width T (1.102 × 2.047 × 0.63 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 37 kN, C0 40.5 kN (2203E prints no Pu for this size), grease limiting speed 7,300 r/min, oil speed 9,700 r/min, mass about 146 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 320/28X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (320/28X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 320/28X designation encode the 28 mm bore and what is 4CC?", "a": "28 mm bore is printed directly after the slash in the slash-size convention. The 52 mm OD and 16 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 320/28X list two speeds, 7,300 and 9,700 r/min?", "a": "The lower figure, 7,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 320/28X at 9,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 320/28X mean?", "a": "Suffix reading on 320/28X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "320-22", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "320-28", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "320-32", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "320-28x", "4cc", "4t-320-28x", "320-28X" ], "locale_variants": {} }, { "sku": "332-28", "brand": "NTN", "manufacturer_designation": "NTN 332/28", "series": "33200-series", "type": "tapered_roller", "d_mm": 28, "D_mm": 58, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 64.5, "static_load_kN": 69.5, "limiting_speed_rpm": 6700, "max_rpm": 6700, "speed_oil_rpm": 8900, "weight_g": 293, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 28 mm bore tapered roller position as 332/28: one cone assembly, one cup, line-contact rollers and a steel cage, rated 64.5 kN basic dynamic and 69.5 kN static on the medium-wide 33200 family. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 332/28 resolves to 28 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The printed contact-angle geometry gives the medium-wide 33200 family its characteristic load split — at 64.5/69.5 kN (C/C0) the static rating is about 1.08× C, typical of tapered bearings proportioned for heavy combined duty. Grease relubrication at 6,700 r/min limiting speed targets the rib contact; if the drive needs 8,900 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 332/28 arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 28 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 332/28.", "The medium-wide 33200 family at 28 mm bore (58×24 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 8,900 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 332/28 at a large fraction of 6,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 15.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 332/28 or the ring will bottom out on the radius instead of the shoulder face.", "Minimum load matters at high speed: an unloaded 332/28 at a large fraction of 6,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 64.5/69.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 332/28 (ISO 355 2DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 332/28?", "a": "332/28 is a metric 4T tapered roller bearing to ISO 355: 28 mm bore, 58 mm outside diameter and 24 mm assembled width T (1.102 × 2.283 × 0.945 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 64.5 kN, C0 69.5 kN (2203E prints no Pu for this size), grease limiting speed 6,700 r/min, oil speed 8,900 r/min, mass about 293 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 332/28?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (332/28); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 332/28 designation encode the 28 mm bore and what is 2DE?", "a": "28 mm bore is printed directly after the slash in the slash-size convention. The 58 mm OD and 24 mm assembled T follow the ISO 355 dimension-series plan. 2DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 332/28 list two speeds, 6,700 and 8,900 r/min?", "a": "The lower figure, 6,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 332/28 at 8,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 332/28 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "332", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2de", "4t-332-28", "332-28" ], "locale_variants": {} }, { "sku": "32006X", "brand": "NTN", "manufacturer_designation": "NTN 32006X", "series": "32000-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 55, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 41.5, "static_load_kN": 46, "limiting_speed_rpm": 6900, "max_rpm": 6900, "speed_oil_rpm": 9200, "weight_g": 172, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32006X denotes the low-section 32000 family tuned for low friction of metric tapered roller bearings, 30 mm bore, 55 mm outside diameter and 17 mm assembled width T (1.181 × 2.165 × 0.669 in) to the ISO 355 boundary plan. The last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 17 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. The 12.5 mm section height over the 30 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 30 mm pair is misadjusted and the 17 mm T set will edge-load in service.", "applications": [ "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32006X.", "The thin 17 mm section of 32006X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 30 mm bore smears the roller ends against the rib.", "Never fit the 30 mm cone by hammering the 55 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 32006X units have no seals: a wheel-hub or gearbox application needs external sealing or the 6,900 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 17 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 41.5/46 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32006X (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32006X?", "a": "32006X is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 55 mm outside diameter and 17 mm assembled width T (1.181 × 2.165 × 0.669 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 41.5 kN, C0 46 kN (2203E prints no Pu for this size), grease limiting speed 6,900 r/min, oil speed 9,200 r/min, mass about 172 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32006X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32006X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32006X designation encode the 30 mm bore and what is 4CC?", "a": "last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 55 mm OD and 17 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32006X list two speeds, 6,900 and 9,200 r/min?", "a": "The lower figure, 6,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32006X at 9,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32006X mean?", "a": "Suffix reading on 32006X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32006X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32006x", "4cc", "4t-32006x", "32006X" ], "locale_variants": {} }, { "sku": "33006", "brand": "NTN", "manufacturer_designation": "NTN 33006", "series": "33000-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 55, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 47, "static_load_kN": 54, "limiting_speed_rpm": 6900, "max_rpm": 6900, "speed_oil_rpm": 9200, "weight_g": 201, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33006 is the NTN 4T catalogue entry for a 30×55×20 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2CE, which is the maker-neutral cross-reference for the 30×55 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. 2203E lists two speed ceilings for 33006: 6,900 r/min with grease lubrication (the limiting speed) and 9,200 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Imperial cross-check for the drawing: 30×55×20 mm is 1.181 × 2.165 × 0.787 in; ISO 355 makes the envelope interchangeable but C/C0, 47/54 kN, is NTN-specific. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 33006 arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33006.", "The thin 20 mm section of 33006 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 30 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 20 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Grease packs must leave free volume in the 20 mm-wide set; over-greasing a paired bearing churning at the 9,200 r/min oil-band speed raises temperature and destroys the preload setting.", "Grease packs must leave free volume in the 20 mm-wide set; over-greasing a paired bearing churning at the 9,200 r/min oil-band speed raises temperature and destroys the preload setting.", "The 47/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33006 (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33006?", "a": "33006 is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 55 mm outside diameter and 20 mm assembled width T (1.181 × 2.165 × 0.787 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 47 kN, C0 54 kN (2203E prints no Pu for this size), grease limiting speed 6,900 r/min, oil speed 9,200 r/min, mass about 201 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33006?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33006); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33006 designation encode the 30 mm bore and what is 2CE?", "a": "last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 55 mm OD and 20 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33006 list two speeds, 6,900 and 9,200 r/min?", "a": "The lower figure, 6,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33006 at 9,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33006 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33006", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "4t-33006", "33006" ], "locale_variants": {} }, { "sku": "30206-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30206", "series": "30200-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 62, "B_mm": 17.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 48.5, "static_load_kN": 48, "limiting_speed_rpm": 6300, "max_rpm": 6300, "speed_oil_rpm": 8400, "weight_g": 236, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30206 in the standard-section 30200 family: 30 mm bore, 62 mm cup OD, 17.25 mm T, with a grease limiting speed of 6,300 r/min and an oil-lubricated ceiling of 8,400 r/min. The last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 17.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 30206, not only the raceway. Catalogue mass of the 30206 set is 236 g (0.009 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Mount the 30 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30206.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30206.", "The standard-section 30200 family at 30 mm bore (62×17.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 8,400 r/min oil ceiling.", "Never fit the 30 mm cone by hammering the 62 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Minimum load matters at high speed: an unloaded 30206 at a large fraction of 6,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 30 mm shoulder geometry, because retrofitting flips the cups.", "The 48.5/48 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30206 (ISO 355 3DB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30206?", "a": "30206 is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 62 mm outside diameter and 17.25 mm assembled width T (1.181 × 2.441 × 0.679 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 48.5 kN, C0 48 kN (2203E prints no Pu for this size), grease limiting speed 6,300 r/min, oil speed 8,400 r/min, mass about 236 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30206?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30206); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30206 designation encode the 30 mm bore and what is 3DB?", "a": "last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 17.25 mm assembled T follow the ISO 355 dimension-series plan. 3DB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30206 list two speeds, 6,300 and 8,400 r/min?", "a": "The lower figure, 6,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30206 at 8,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30206 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30206", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "30206-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3db", "4t-30206", "30206", "30206-NTN" ], "locale_variants": {} }, { "sku": "32206-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32206", "series": "32200-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 62, "B_mm": 21.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 60.5, "static_load_kN": 64, "limiting_speed_rpm": 6300, "max_rpm": 6300, "speed_oil_rpm": 8400, "weight_g": 299, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32206 denotes the heavy-section 32200 family of metric tapered roller bearings, 30 mm bore, 62 mm outside diameter and 21.25 mm assembled width T (1.181 × 2.441 × 0.837 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3DC, which is the maker-neutral cross-reference for the 30×62 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. At 60.5 kN C the bearing offers about 2.0 kN of dynamic capacity per millimetre of the 30 mm bore — compare any substitution on this ratio and the 21.25 mm assembled T, not on bore alone. Selection: C 60.5 kN against C0 64 kN gives a C0/C ratio of 1.06 for the 30 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. When pairing 32206 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32206.", "The heavy-section 32200 family at 30 mm bore (62×21.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 8,400 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 32206 at a large fraction of 6,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 16.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32206 or the ring will bottom out on the radius instead of the shoulder face.", "Open 32206 units have no seals: a wheel-hub or gearbox application needs external sealing or the 6,300 r/min grease figure is meaningless once water reaches the cone rib.", "The 60.5/64 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32206 (ISO 355 3DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32206?", "a": "32206 is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 62 mm outside diameter and 21.25 mm assembled width T (1.181 × 2.441 × 0.837 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 60.5 kN, C0 64 kN (2203E prints no Pu for this size), grease limiting speed 6,300 r/min, oil speed 8,400 r/min, mass about 299 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32206?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32206); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32206 designation encode the 30 mm bore and what is 3DC?", "a": "last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 21.25 mm assembled T follow the ISO 355 dimension-series plan. 3DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32206 list two speeds, 6,300 and 8,400 r/min?", "a": "The lower figure, 6,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32206 at 8,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32206 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32206", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32206-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32206-SKF", "equiv_brand": "SKF", "level": "partial", "note": "Same 30×62×21.25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3dc", "4t-32206", "32206", "32206-NTN" ], "locale_variants": {} }, { "sku": "32206C", "brand": "NTN", "manufacturer_designation": "NTN 32206C", "series": "32200-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 62, "B_mm": 21.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 55.5, "static_load_kN": 60, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8100, "weight_g": 297, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32206C in the heavy-section 32200 family: 30 mm bore, 62 mm cup OD, 21.25 mm T, with a grease limiting speed of 6,100 r/min and an oil-lubricated ceiling of 8,100 r/min. The last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 21.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. 2203E lists two speed ceilings for 32206C: 6,100 r/min with grease lubrication (the limiting speed) and 8,100 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. The 1.9 kN-per-mm-bore capacity figure for 32206C summarises the 55.5 kN rating over 30 mm bore; use it to sanity-check an interchange candidate before swapping brands. When pairing 32206C with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32206C.", "The heavy-section 32200 family at 30 mm bore (62×21.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 8,100 r/min oil ceiling.", "Do not confuse T (21.25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32206C by size alone can deliver the wrong contact-angle execution for a pinion position.", "Grease packs must leave free volume in the 21.25 mm-wide set; over-greasing a paired bearing churning at the 8,100 r/min oil-band speed raises temperature and destroys the preload setting.", "The 55.5/60 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32206C (ISO 355 5DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32206C?", "a": "32206C is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 62 mm outside diameter and 21.25 mm assembled width T (1.181 × 2.441 × 0.837 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 55.5 kN, C0 60 kN (2203E prints no Pu for this size), grease limiting speed 6,100 r/min, oil speed 8,100 r/min, mass about 297 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32206C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32206C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32206C designation encode the 30 mm bore and what is 5DC?", "a": "last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 21.25 mm assembled T follow the ISO 355 dimension-series plan. 5DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32206C list two speeds, 6,100 and 8,100 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32206C at 8,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32206C mean?", "a": "Suffix reading on 32206C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32206C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32206c", "4t-32206c", "5dc", "32206C" ], "locale_variants": {} }, { "sku": "33206-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33206", "series": "33200-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 62, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 72, "static_load_kN": 77, "limiting_speed_rpm": 6300, "max_rpm": 6300, "speed_oil_rpm": 8400, "weight_g": 348, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33206 is the NTN 4T catalogue entry for a 30×62×25 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. The last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. With no letter after the number, 33206 is the basic open 4T execution: steel cage, normal adjustment, no seal or special internal-design suffix in the order code. Selection: C 72 kN against C0 77 kN gives a C0/C ratio of 1.07 for the 30 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Mount the 30 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 33206.", "applications": [ "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33206.", "The medium-wide 33200 family at 30 mm bore (62×25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 8,400 r/min oil ceiling.", "Open 33206 units have no seals: a wheel-hub or gearbox application needs external sealing or the 6,300 r/min grease figure is meaningless once water reaches the cone rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 30 mm shoulder geometry, because retrofitting flips the cups.", "ISO 355 makes the 30×62 mm envelope interchangeable but not the ratings: NTN prints 72/77 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 72/77 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33206 (ISO 355 2DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33206?", "a": "33206 is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 62 mm outside diameter and 25 mm assembled width T (1.181 × 2.441 × 0.984 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 72 kN, C0 77 kN (2203E prints no Pu for this size), grease limiting speed 6,300 r/min, oil speed 8,400 r/min, mass about 348 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33206?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33206); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33206 designation encode the 30 mm bore and what is 2DE?", "a": "last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 25 mm assembled T follow the ISO 355 dimension-series plan. 2DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33206 list two speeds, 6,300 and 8,400 r/min?", "a": "The lower figure, 6,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33206 at 8,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33206 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33206", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2de", "4t-33206", "33206", "33206-NTN" ], "locale_variants": {} }, { "sku": "30306-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30306", "series": "30300-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 72, "B_mm": 20.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 66.5, "static_load_kN": 61, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 404, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 30 mm shaft with a thrust component, NTN lists 30306, a metric 4T tapered roller bearing of 66.5 kN C and 61 kN C0 inside the 72 mm OD, 20.75 mm-wide assembled set. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30306 by the metric ISO 355 number (ISO series abbreviation 2FB): 30 mm bore, 72 mm OD. At 66.5 kN C the bearing offers about 2.2 kN of dynamic capacity per millimetre of the 30 mm bore — compare any substitution on this ratio and the 20.75 mm assembled T, not on bore alone. Grease relubrication at 5,700 r/min limiting speed targets the rib contact; if the drive needs 7,600 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Mount the 30 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30306.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30306.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 30 mm bore; do not swap to the lighter family without re-checking the 5,700 r/min grease limit and the thrust load split.", "The 21.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30306 or the ring will bottom out on the radius instead of the shoulder face.", "Grease packs must leave free volume in the 20.75 mm-wide set; over-greasing a paired bearing churning at the 7,600 r/min oil-band speed raises temperature and destroys the preload setting.", "Open 30306 units have no seals: a wheel-hub or gearbox application needs external sealing or the 5,700 r/min grease figure is meaningless once water reaches the cone rib.", "The 66.5/61 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30306 (ISO 355 2FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30306?", "a": "30306 is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 72 mm outside diameter and 20.75 mm assembled width T (1.181 × 2.835 × 0.817 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 66.5 kN, C0 61 kN (2203E prints no Pu for this size), grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 404 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30306?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30306); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30306 designation encode the 30 mm bore and what is 2FB?", "a": "last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 72 mm OD and 20.75 mm assembled T follow the ISO 355 dimension-series plan. 2FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30306 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30306 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30306 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30306", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "30306-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=165", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fb", "4t-30306", "30306", "30306-NTN" ], "locale_variants": {} }, { "sku": "30306CA", "brand": "NTN", "manufacturer_designation": "NTN 30306CA", "series": "30300-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 72, "B_mm": 20.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 65, "static_load_kN": 58.5, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7300, "weight_g": 399, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30306CA in the large-OD 30300 family with the steeper contact angle: 30 mm bore, 72 mm cup OD, 20.75 mm T, with a grease limiting speed of 5,500 r/min and an oil-lubricated ceiling of 7,300 r/min. The last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 20.75 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Speed planning uses both catalogue columns: grease 5,500 r/min is the cage/rib mechanical ceiling for 30306CA, oil 7,300 r/min is available with circulating oil — a 1,800 r/min margin at this size. Open 4T bearings need application seals; without them the grease at the cone rib of 30306CA washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30306CA.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 30 mm bore; do not swap to the lighter family without re-checking the 5,500 r/min grease limit and the thrust load split.", "Open 30306CA units have no seals: a wheel-hub or gearbox application needs external sealing or the 5,500 r/min grease figure is meaningless once water reaches the cone rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 30 mm shoulder geometry, because retrofitting flips the cups.", "Replacing one half of an adjusted pair without resetting end play negates the 20.75 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 65/58.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30306CA; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30306CA?", "a": "30306CA is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 72 mm outside diameter and 20.75 mm assembled width T (1.181 × 2.835 × 0.817 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 65 kN, C0 58.5 kN (2203E prints no Pu for this size), grease limiting speed 5,500 r/min, oil speed 7,300 r/min, mass about 399 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30306CA?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30306CA); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30306CA designation encode the 30 mm bore?", "a": "last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 72 mm OD and 20.75 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30306CA list two speeds, 5,500 and 7,300 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30306CA at 7,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30306CA mean?", "a": "Suffix reading on 30306CA: the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30306CA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30306ca", "4t-30306ca", "30306CA" ], "locale_variants": {} }, { "sku": "30306D", "brand": "NTN", "manufacturer_designation": "NTN 30306D", "series": "30300-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 72, "B_mm": 20.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53.5, "static_load_kN": 51.5, "limiting_speed_rpm": 5000, "max_rpm": 5000, "speed_oil_rpm": 6700, "weight_g": 394, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 30306D denotes the large-OD 30300 family with the steeper contact angle of metric tapered roller bearings, 30 mm bore, 72 mm outside diameter and 20.75 mm assembled width T (1.181 × 2.835 × 0.817 in) to the ISO 355 boundary plan. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30306D resolves to 30 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 30306D cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The 1.8 kN-per-mm-bore capacity figure for 30306D summarises the 53.5 kN rating over 30 mm bore; use it to sanity-check an interchange candidate before swapping brands. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 30306D arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30306D.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 30 mm bore; do not swap to the lighter family without re-checking the 5,000 r/min grease limit and the thrust load split.", "ISO 355 makes the 30×72 mm envelope interchangeable but not the ratings: NTN prints 53.5/51.5 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "ISO 355 makes the 30×72 mm envelope interchangeable but not the ratings: NTN prints 53.5/51.5 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Do not confuse T (20.75 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 53.5/51.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30306D (ISO 355 7FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30306D?", "a": "30306D is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 72 mm outside diameter and 20.75 mm assembled width T (1.181 × 2.835 × 0.817 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53.5 kN, C0 51.5 kN (2203E prints no Pu for this size), grease limiting speed 5,000 r/min, oil speed 6,700 r/min, mass about 394 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30306D?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30306D); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30306D designation encode the 30 mm bore and what is 7FB?", "a": "last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 72 mm OD and 20.75 mm assembled T follow the ISO 355 dimension-series plan. 7FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30306D list two speeds, 5,000 and 6,700 r/min?", "a": "The lower figure, 5,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30306D at 6,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30306D mean?", "a": "Suffix reading on 30306D: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30306D", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30306d", "4t-30306d", "7fb", "30306D" ], "locale_variants": {} }, { "sku": "32306-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32306", "series": "32300-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 72, "B_mm": 28.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 89.5, "static_load_kN": 90, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 577, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 30 mm bore tapered roller position as 32306: one cone assembly, one cup, line-contact rollers and a steel cage, rated 89.5 kN basic dynamic and 90 kN static on the extra-heavy 32300 family. The last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 28.75 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32306, since running clearance is set during assembly. 2203E does not print a Pu fatigue load limit for 32306; life work for this size uses the 89.5/90 kN C/C0 pair directly. When pairing 32306 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32306.", "The extra-heavy 32300 family at 30 mm bore (72×28.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 7,600 r/min oil ceiling.", "Open 32306 units have no seals: a wheel-hub or gearbox application needs external sealing or the 5,700 r/min grease figure is meaningless once water reaches the cone rib.", "Minimum load matters at high speed: an unloaded 32306 at a large fraction of 5,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 30 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 89.5/90 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32306 (ISO 355 2FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32306?", "a": "32306 is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 72 mm outside diameter and 28.75 mm assembled width T (1.181 × 2.835 × 1.132 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 89.5 kN, C0 90 kN (2203E prints no Pu for this size), grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 577 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32306?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32306); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32306 designation encode the 30 mm bore and what is 2FD?", "a": "last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 72 mm OD and 28.75 mm assembled T follow the ISO 355 dimension-series plan. 2FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32306 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32306 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32306 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32306", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fd", "4t-32306", "32306", "32306-NTN" ], "locale_variants": {} }, { "sku": "32306C", "brand": "NTN", "manufacturer_designation": "NTN 32306C", "series": "32300-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 72, "B_mm": 28.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 88, "static_load_kN": 94, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7300, "weight_g": 591, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 30 mm bore tapered roller position as 32306C: one cone assembly, one cup, line-contact rollers and a steel cage, rated 88 kN basic dynamic and 94 kN static on the extra-heavy 32300 family. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 5FD, which is the maker-neutral cross-reference for the 30×72 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. Individually mounted, 32306C takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The 2.9 kN-per-mm-bore capacity figure for 32306C summarises the 88 kN rating over 30 mm bore; use it to sanity-check an interchange candidate before swapping brands. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 32306C; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion bearings of this 30 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32306C.", "The extra-heavy 32300 family at 30 mm bore (72×28.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 7,300 r/min oil ceiling.", "Never fit the 30 mm cone by hammering the 72 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Minimum load matters at high speed: an unloaded 32306C at a large fraction of 5,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Never fit the 30 mm cone by hammering the 72 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 88/94 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32306C (ISO 355 5FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32306C?", "a": "32306C is a metric 4T tapered roller bearing to ISO 355: 30 mm bore, 72 mm outside diameter and 28.75 mm assembled width T (1.181 × 2.835 × 1.132 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 88 kN, C0 94 kN (2203E prints no Pu for this size), grease limiting speed 5,500 r/min, oil speed 7,300 r/min, mass about 591 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32306C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32306C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32306C designation encode the 30 mm bore and what is 5FD?", "a": "last two digits 06 are the ISO bore code, ×5 = 30 mm (codes 00–03 use the 10/12/15/17 exception table). The 72 mm OD and 28.75 mm assembled T follow the ISO 355 dimension-series plan. 5FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32306C list two speeds, 5,500 and 7,300 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32306C at 7,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32306C mean?", "a": "Suffix reading on 32306C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32306C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32306c", "4t-32306c", "5fd", "32306C" ], "locale_variants": {} }, { "sku": "320-32X", "brand": "NTN", "manufacturer_designation": "NTN 320/32X", "series": "32000-series", "type": "tapered_roller", "d_mm": 32, "D_mm": 58, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 41, "static_load_kN": 46.5, "limiting_speed_rpm": 6600, "max_rpm": 6600, "speed_oil_rpm": 8700, "weight_g": 188, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 320/32X denotes the low-section 32000 family tuned for low friction of metric tapered roller bearings, 32 mm bore, 58 mm outside diameter and 17 mm assembled width T (1.26 × 2.283 × 0.669 in) to the ISO 355 boundary plan. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 320/32X by the metric ISO 355 number (ISO series abbreviation 4CC): 32 mm bore, 58 mm OD. 2203E lists two speed ceilings for 320/32X: 6,600 r/min with grease lubrication (the limiting speed) and 8,700 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Grease relubrication at 6,600 r/min limiting speed targets the rib contact; if the drive needs 8,700 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Open 4T bearings need application seals; without them the grease at the cone rib of 320/32X washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 32 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 320/32X.", "The thin 17 mm section of 320/32X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 32 mm bore smears the roller ends against the rib.", "Grease packs must leave free volume in the 17 mm-wide set; over-greasing a paired bearing churning at the 8,700 r/min oil-band speed raises temperature and destroys the preload setting.", "Never fit the 32 mm cone by hammering the 58 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume in the 17 mm-wide set; over-greasing a paired bearing churning at the 8,700 r/min oil-band speed raises temperature and destroys the preload setting.", "The 41/46.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 320/32X (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 320/32X?", "a": "320/32X is a metric 4T tapered roller bearing to ISO 355: 32 mm bore, 58 mm outside diameter and 17 mm assembled width T (1.26 × 2.283 × 0.669 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 41 kN, C0 46.5 kN (2203E prints no Pu for this size), grease limiting speed 6,600 r/min, oil speed 8,700 r/min, mass about 188 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 320/32X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (320/32X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 320/32X designation encode the 32 mm bore and what is 4CC?", "a": "32 mm bore is printed directly after the slash in the slash-size convention. The 58 mm OD and 17 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 320/32X list two speeds, 6,600 and 8,700 r/min?", "a": "The lower figure, 6,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 320/32X at 8,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 320/32X mean?", "a": "Suffix reading on 320/32X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "320-22", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "320-28", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "320-32", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "320-32x", "4cc", "4t-320-32x", "320-32X" ], "locale_variants": {} }, { "sku": "332-32", "brand": "NTN", "manufacturer_designation": "NTN 332/32", "series": "33200-series", "type": "tapered_roller", "d_mm": 32, "D_mm": 65, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 78.5, "static_load_kN": 85, "limiting_speed_rpm": 6000, "max_rpm": 6000, "speed_oil_rpm": 8000, "weight_g": 394, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "332/32 belongs to the NTN metric 4T tapered roller range (medium-wide 33200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 332/32 by the metric ISO 355 number (ISO series abbreviation 2DE): 32 mm bore, 65 mm OD. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Selection: C 78.5 kN against C0 85 kN gives a C0/C ratio of 1.08 for the 32 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 332/32 arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Hub and pinion bearings of this 32 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 332/32.", "The medium-wide 33200 family at 32 mm bore (65×26 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 8,000 r/min oil ceiling.", "ISO 355 makes the 32×65 mm envelope interchangeable but not the ratings: NTN prints 78.5/85 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 32 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Replacing one half of an adjusted pair without resetting end play negates the 26 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 78.5/85 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 332/32 (ISO 355 2DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 332/32?", "a": "332/32 is a metric 4T tapered roller bearing to ISO 355: 32 mm bore, 65 mm outside diameter and 26 mm assembled width T (1.26 × 2.559 × 1.024 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 78.5 kN, C0 85 kN (2203E prints no Pu for this size), grease limiting speed 6,000 r/min, oil speed 8,000 r/min, mass about 394 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 332/32?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (332/32); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 332/32 designation encode the 32 mm bore and what is 2DE?", "a": "32 mm bore is printed directly after the slash in the slash-size convention. The 65 mm OD and 26 mm assembled T follow the ISO 355 dimension-series plan. 2DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 332/32 list two speeds, 6,000 and 8,000 r/min?", "a": "The lower figure, 6,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 332/32 at 8,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 332/32 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "332", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2de", "4t-332-32", "332-32" ], "locale_variants": {} }, { "sku": "323-32C", "brand": "NTN", "manufacturer_designation": "NTN 323/32C", "series": "32300-series", "type": "tapered_roller", "d_mm": 32, "D_mm": 75, "B_mm": 29.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 93.5, "static_load_kN": 102, "limiting_speed_rpm": 5200, "max_rpm": 5200, "speed_oil_rpm": 6900, "weight_g": 652, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 32 mm bore tapered roller position as 323/32C: one cone assembly, one cup, line-contact rollers and a steel cage, rated 93.5 kN basic dynamic and 102 kN static on the extra-heavy 32300 family. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 323/32C by the metric ISO 355 number (ISO series abbreviation 5FD): 32 mm bore, 75 mm OD. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 323/32C, since running clearance is set during assembly. The two speed columns differ by a factor of .75 (grease/limiting 5,200 vs oil 6,900 r/min); heat generation at the cone rib decides which lubrication a real 323/32C arrangement can sustain. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 323/32C; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion bearings of this 32 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 323/32C.", "The extra-heavy 32300 family at 32 mm bore (75×29.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 6,900 r/min oil ceiling.", "ISO 355 makes the 32×75 mm envelope interchangeable but not the ratings: NTN prints 93.5/102 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "ISO 355 makes the 32×75 mm envelope interchangeable but not the ratings: NTN prints 93.5/102 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 32 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 93.5/102 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 323/32C (ISO 355 5FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 323/32C?", "a": "323/32C is a metric 4T tapered roller bearing to ISO 355: 32 mm bore, 75 mm outside diameter and 29.75 mm assembled width T (1.26 × 2.953 × 1.171 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 93.5 kN, C0 102 kN (2203E prints no Pu for this size), grease limiting speed 5,200 r/min, oil speed 6,900 r/min, mass about 652 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 323/32C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (323/32C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 323/32C designation encode the 32 mm bore and what is 5FD?", "a": "32 mm bore is printed directly after the slash in the slash-size convention. The 75 mm OD and 29.75 mm assembled T follow the ISO 355 dimension-series plan. 5FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 323/32C list two speeds, 5,200 and 6,900 r/min?", "a": "The lower figure, 5,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 323/32C at 6,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 323/32C mean?", "a": "Suffix reading on 323/32C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "323", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "323-32c", "4t-323-32c", "5fd", "323-32C" ], "locale_variants": {} }, { "sku": "32907XU", "brand": "NTN", "manufacturer_designation": "NTN 32907XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 55, "B_mm": 14, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 30.5, "static_load_kN": 37.5, "fatigue_load_limit_kN": 4.6, "limiting_speed_rpm": 6800, "max_rpm": 6800, "speed_oil_rpm": 9000, "weight_g": 121, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 35 mm shaft with a thrust component, NTN lists 32907XU, a metric 4T tapered roller bearing of 30.5 kN C and 37.5 kN C0 inside the 55 mm OD, 14 mm-wide assembled set. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32907XU resolves to 35 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The 10.0 mm radial section carries the roller complement across the 35–55 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Grease relubrication at 6,800 r/min limiting speed targets the rib contact; if the drive needs 9,000 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 32907XU; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32907XU.", "The thin 14 mm section of 32907XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 35 mm bore smears the roller ends against the rib.", "Do not confuse T (14 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Grease packs must leave free volume in the 14 mm-wide set; over-greasing a paired bearing churning at the 9,000 r/min oil-band speed raises temperature and destroys the preload setting.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32907XU by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 30.5/37.5 kN ratings and 4.6 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32907XU (ISO 355 2BD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32907XU?", "a": "32907XU is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 55 mm outside diameter and 14 mm assembled width T (1.378 × 2.165 × 0.551 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 30.5 kN, C0 37.5 kN, Pu 4.6 kN, grease limiting speed 6,800 r/min, oil speed 9,000 r/min, mass about 121 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32907XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32907XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32907XU designation encode the 35 mm bore and what is 2BD?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 55 mm OD and 14 mm assembled T follow the ISO 355 dimension-series plan. 2BD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32907XU list two speeds, 6,800 and 9,000 r/min?", "a": "The lower figure, 6,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32907XU at 9,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32907XU mean?", "a": "Suffix reading on 32907XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32907XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bd", "32907xu", "32907XU" ], "locale_variants": {} }, { "sku": "32007X", "brand": "NTN", "manufacturer_designation": "NTN 32007X", "series": "32000-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 62, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 46, "static_load_kN": 52.5, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8100, "weight_g": 223, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32007X in the low-section 32000 family tuned for low friction: 35 mm bore, 62 mm cup OD, 18 mm T, with a grease limiting speed of 6,100 r/min and an oil-lubricated ceiling of 8,100 r/min. Digit by digit, the bare number identifies the low-section 32000 family tuned for low friction and a bore code resolving to 35 mm; 62 mm OD and 18 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32007X cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Grease relubrication at 6,100 r/min limiting speed targets the rib contact; if the drive needs 8,100 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Open 4T bearings need application seals; without them the grease at the cone rib of 32007X washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32007X.", "The thin 18 mm section of 32007X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 35 mm bore smears the roller ends against the rib.", "Grease packs must leave free volume in the 18 mm-wide set; over-greasing a paired bearing churning at the 8,100 r/min oil-band speed raises temperature and destroys the preload setting.", "Replacing one half of an adjusted pair without resetting end play negates the 18 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (18 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 46/52.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32007X (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32007X?", "a": "32007X is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 62 mm outside diameter and 18 mm assembled width T (1.378 × 2.441 × 0.709 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 46 kN, C0 52.5 kN (2203E prints no Pu for this size), grease limiting speed 6,100 r/min, oil speed 8,100 r/min, mass about 223 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32007X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32007X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32007X designation encode the 35 mm bore and what is 4CC?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 18 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32007X list two speeds, 6,100 and 8,100 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32007X at 8,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32007X mean?", "a": "Suffix reading on 32007X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32007X-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32007x", "4cc", "4t-32007x", "32007X" ], "locale_variants": {} }, { "sku": "33007", "brand": "NTN", "manufacturer_designation": "NTN 33007", "series": "33000-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 62, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 56, "static_load_kN": 66.5, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8100, "weight_g": 263, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 33007 in the slim 33000 family: 35 mm bore, 62 mm cup OD, 21 mm T, with a grease limiting speed of 6,100 r/min and an oil-lubricated ceiling of 8,100 r/min. Digit by digit, the bare number identifies the slim 33000 family and a bore code resolving to 35 mm; 62 mm OD and 21 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 33007 cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Grease relubrication at 6,100 r/min limiting speed targets the rib contact; if the drive needs 8,100 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Fillet radii must clear the ring chamfers of the 62 mm cup and 35 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33007.", "The thin 21 mm section of 33007 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 35 mm bore smears the roller ends against the rib.", "ISO 355 makes the 35×62 mm envelope interchangeable but not the ratings: NTN prints 56/66.5 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33007 by size alone can deliver the wrong contact-angle execution for a pinion position.", "Do not confuse T (21 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 56/66.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33007 (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33007?", "a": "33007 is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 62 mm outside diameter and 21 mm assembled width T (1.378 × 2.441 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 56 kN, C0 66.5 kN (2203E prints no Pu for this size), grease limiting speed 6,100 r/min, oil speed 8,100 r/min, mass about 263 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33007?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33007); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33007 designation encode the 35 mm bore and what is 2CE?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 21 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33007 list two speeds, 6,100 and 8,100 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33007 at 8,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33007 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33007", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "4t-33007", "33007" ], "locale_variants": {} }, { "sku": "30207-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30207", "series": "30200-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 72, "B_mm": 18.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 61.5, "static_load_kN": 61.5, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7400, "weight_g": 341, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 35 mm shaft with a thrust component, NTN lists 30207, a metric 4T tapered roller bearing of 61.5 kN C and 61.5 kN C0 inside the 72 mm OD, 18.25 mm-wide assembled set. Digit by digit, the bare number identifies the standard-section 30200 family and a bore code resolving to 35 mm; 72 mm OD and 18.25 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. 2203E does not print a Pu fatigue load limit for 30207; life work for this size uses the 61.5/61.5 kN C/C0 pair directly. Mount the 35 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30207.", "applications": [ "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30207.", "The standard-section 30200 family at 35 mm bore (72×18.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 7,400 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 35 mm shoulder geometry, because retrofitting flips the cups.", "Do not confuse T (18.25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 18.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 61.5/61.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30207 (ISO 355 3DB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30207?", "a": "30207 is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 72 mm outside diameter and 18.25 mm assembled width T (1.378 × 2.835 × 0.719 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 61.5 kN, C0 61.5 kN (2203E prints no Pu for this size), grease limiting speed 5,500 r/min, oil speed 7,400 r/min, mass about 341 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30207?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30207); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30207 designation encode the 35 mm bore and what is 3DB?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 72 mm OD and 18.25 mm assembled T follow the ISO 355 dimension-series plan. 3DB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30207 list two speeds, 5,500 and 7,400 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30207 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30207 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30207", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3db", "4t-30207", "30207", "30207-NTN" ], "locale_variants": {} }, { "sku": "32207-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32207", "series": "32200-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 72, "B_mm": 24.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 80.5, "static_load_kN": 87, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7400, "weight_g": 455, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 35 mm bore tapered roller position as 32207: one cone assembly, one cup, line-contact rollers and a steel cage, rated 80.5 kN basic dynamic and 87 kN static on the heavy-section 32200 family. The last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 24.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The 18.5 mm radial section carries the roller complement across the 35–72 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Speed planning uses both catalogue columns: grease 5,500 r/min is the cage/rib mechanical ceiling for 32207, oil 7,400 r/min is available with circulating oil — a 1,900 r/min margin at this size. When pairing 32207 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32207.", "The heavy-section 32200 family at 35 mm bore (72×24.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 7,400 r/min oil ceiling.", "The 18.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32207 or the ring will bottom out on the radius instead of the shoulder face.", "ISO 355 makes the 35×72 mm envelope interchangeable but not the ratings: NTN prints 80.5/87 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32207 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 80.5/87 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32207 (ISO 355 3DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32207?", "a": "32207 is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 72 mm outside diameter and 24.25 mm assembled width T (1.378 × 2.835 × 0.955 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 80.5 kN, C0 87 kN (2203E prints no Pu for this size), grease limiting speed 5,500 r/min, oil speed 7,400 r/min, mass about 455 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32207?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32207); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32207 designation encode the 35 mm bore and what is 3DC?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 72 mm OD and 24.25 mm assembled T follow the ISO 355 dimension-series plan. 3DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32207 list two speeds, 5,500 and 7,400 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32207 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32207 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32207", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32207-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32207-SKF", "equiv_brand": "SKF", "level": "partial", "note": "Same 35×72×24.25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3dc", "4t-32207", "32207", "32207-NTN" ], "locale_variants": {} }, { "sku": "32207C", "brand": "NTN", "manufacturer_designation": "NTN 32207C", "series": "32200-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 72, "B_mm": 24.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 75.5, "static_load_kN": 85.5, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7100, "weight_g": 461, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32207C is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 35×72 mm ISO 355 envelope, with 24.25 mm overall assembled width T. Digit by digit, the bare number identifies the heavy-section 32200 family and a bore code resolving to 35 mm; 72 mm OD and 24.25 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. Individually mounted, 32207C takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Imperial cross-check for the drawing: 35×72×24.25 mm is 1.378 × 2.835 × 0.955 in; ISO 355 makes the envelope interchangeable but C/C0, 75.5/85.5 kN, is NTN-specific. Fillet radii must clear the ring chamfers of the 72 mm cup and 35 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32207C.", "The heavy-section 32200 family at 35 mm bore (72×24.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 7,100 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 24.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Grease packs must leave free volume in the 24.25 mm-wide set; over-greasing a paired bearing churning at the 7,100 r/min oil-band speed raises temperature and destroys the preload setting.", "Never fit the 35 mm cone by hammering the 72 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 75.5/85.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32207C (ISO 355 5DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32207C?", "a": "32207C is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 72 mm outside diameter and 24.25 mm assembled width T (1.378 × 2.835 × 0.955 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 75.5 kN, C0 85.5 kN (2203E prints no Pu for this size), grease limiting speed 5,300 r/min, oil speed 7,100 r/min, mass about 461 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32207C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32207C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32207C designation encode the 35 mm bore and what is 5DC?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 72 mm OD and 24.25 mm assembled T follow the ISO 355 dimension-series plan. 5DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32207C list two speeds, 5,300 and 7,100 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32207C at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32207C mean?", "a": "Suffix reading on 32207C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32207C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32207c", "4t-32207c", "5dc", "32207C" ], "locale_variants": {} }, { "sku": "33207-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33207", "series": "33200-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 72, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 97, "static_load_kN": 109, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7400, "weight_g": 539, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 35 mm bore tapered roller position as 33207: one cone assembly, one cup, line-contact rollers and a steel cage, rated 97 kN basic dynamic and 109 kN static on the medium-wide 33200 family. Digit by digit, the bare number identifies the medium-wide 33200 family and a bore code resolving to 35 mm; 72 mm OD and 28 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN grades 4T metric bearings as open bearings without integral seals; at 35 mm bore the application supplies the seals and the grease fill or oil supply to the 2DE ISO 355 assembly. The two speed columns differ by a factor of .74 (grease/limiting 5,500 vs oil 7,400 r/min); heat generation at the cone rib decides which lubrication a real 33207 arrangement can sustain. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 35 mm pair is misadjusted and the 28 mm T set will edge-load in service.", "applications": [ "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33207.", "The medium-wide 33200 family at 35 mm bore (72×28 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 7,400 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 33207 at a large fraction of 5,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Open 33207 units have no seals: a wheel-hub or gearbox application needs external sealing or the 5,500 r/min grease figure is meaningless once water reaches the cone rib.", "The 18.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33207 or the ring will bottom out on the radius instead of the shoulder face.", "The 97/109 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33207 (ISO 355 2DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33207?", "a": "33207 is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 72 mm outside diameter and 28 mm assembled width T (1.378 × 2.835 × 1.102 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 97 kN, C0 109 kN (2203E prints no Pu for this size), grease limiting speed 5,500 r/min, oil speed 7,400 r/min, mass about 539 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33207?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33207); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33207 designation encode the 35 mm bore and what is 2DE?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 72 mm OD and 28 mm assembled T follow the ISO 355 dimension-series plan. 2DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33207 list two speeds, 5,500 and 7,400 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33207 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33207 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33207", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "33207-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2de", "4t-33207", "33207", "33207-NTN" ], "locale_variants": {} }, { "sku": "30307-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30307", "series": "30300-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 80, "B_mm": 22.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 83, "static_load_kN": 77, "limiting_speed_rpm": 5000, "max_rpm": 5000, "speed_oil_rpm": 6600, "weight_g": 535, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30307 in the large-OD 30300 family with the steeper contact angle: 35 mm bore, 80 mm cup OD, 22.75 mm T, with a grease limiting speed of 5,000 r/min and an oil-lubricated ceiling of 6,600 r/min. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2FB, which is the maker-neutral cross-reference for the 35×80 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 30307, not only the raceway. The 22.5 mm section height over the 35 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 35 mm pair is misadjusted and the 22.75 mm T set will edge-load in service.", "applications": [ "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30307.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 35 mm bore; do not swap to the lighter family without re-checking the 5,000 r/min grease limit and the thrust load split.", "Never fit the 35 mm cone by hammering the 80 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 35 mm shoulder geometry, because retrofitting flips the cups.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 35 mm shoulder geometry, because retrofitting flips the cups.", "The 83/77 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30307 (ISO 355 2FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30307?", "a": "30307 is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 80 mm outside diameter and 22.75 mm assembled width T (1.378 × 3.15 × 0.896 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 83 kN, C0 77 kN (2203E prints no Pu for this size), grease limiting speed 5,000 r/min, oil speed 6,600 r/min, mass about 535 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30307?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30307); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30307 designation encode the 35 mm bore and what is 2FB?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 22.75 mm assembled T follow the ISO 355 dimension-series plan. 2FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30307 list two speeds, 5,000 and 6,600 r/min?", "a": "The lower figure, 5,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30307 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30307 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30307", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "30307-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fb", "4t-30307", "30307", "30307-NTN" ], "locale_variants": {} }, { "sku": "30307C", "brand": "NTN", "manufacturer_designation": "NTN 30307C", "series": "30300-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 80, "B_mm": 22.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 73.5, "static_load_kN": 68.5, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 517, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30307C is the NTN 4T catalogue entry for a 35×80×22.75 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30307C by the metric ISO 355 number: 35 mm bore, 80 mm OD. Individually mounted, 30307C takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Selection: C 73.5 kN against C0 68.5 kN gives a C0/C ratio of 0.93 for the 35 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 35 mm pair is misadjusted and the 22.75 mm T set will edge-load in service.", "applications": [ "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30307C.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 35 mm bore; do not swap to the lighter family without re-checking the 4,800 r/min grease limit and the thrust load split.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30307C by size alone can deliver the wrong contact-angle execution for a pinion position.", "Replacing one half of an adjusted pair without resetting end play negates the 22.75 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never fit the 35 mm cone by hammering the 80 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 73.5/68.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30307C; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30307C?", "a": "30307C is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 80 mm outside diameter and 22.75 mm assembled width T (1.378 × 3.15 × 0.896 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 73.5 kN, C0 68.5 kN (2203E prints no Pu for this size), grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 517 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30307C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30307C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30307C designation encode the 35 mm bore?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 22.75 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30307C list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30307C at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30307C mean?", "a": "Suffix reading on 30307C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30307C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30307c", "4t-30307c", "30307C" ], "locale_variants": {} }, { "sku": "30307D", "brand": "NTN", "manufacturer_designation": "NTN 30307D", "series": "30300-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 80, "B_mm": 22.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 70.5, "static_load_kN": 70, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5800, "weight_g": 527, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30307D in the large-OD 30300 family with the steeper contact angle: 35 mm bore, 80 mm cup OD, 22.75 mm T, with a grease limiting speed of 4,400 r/min and an oil-lubricated ceiling of 5,800 r/min. The last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 22.75 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The printed contact-angle geometry gives the large-OD 30300 family with the steeper contact angle its characteristic load split — at 70.5/70 kN (C/C0) the static rating is about 0.99× C, typical of tapered bearings proportioned for heavy combined duty. Imperial cross-check for the drawing: 35×80×22.75 mm is 1.378 × 3.15 × 0.896 in; ISO 355 makes the envelope interchangeable but C/C0, 70.5/70 kN, is NTN-specific. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 30307D; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30307D.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 35 mm bore; do not swap to the lighter family without re-checking the 4,400 r/min grease limit and the thrust load split.", "Never fit the 35 mm cone by hammering the 80 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 30307D units have no seals: a wheel-hub or gearbox application needs external sealing or the 4,400 r/min grease figure is meaningless once water reaches the cone rib.", "Minimum load matters at high speed: an unloaded 30307D at a large fraction of 4,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 70.5/70 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30307D (ISO 355 7FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30307D?", "a": "30307D is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 80 mm outside diameter and 22.75 mm assembled width T (1.378 × 3.15 × 0.896 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 70.5 kN, C0 70 kN (2203E prints no Pu for this size), grease limiting speed 4,400 r/min, oil speed 5,800 r/min, mass about 527 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30307D?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30307D); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30307D designation encode the 35 mm bore and what is 7FB?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 22.75 mm assembled T follow the ISO 355 dimension-series plan. 7FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30307D list two speeds, 4,400 and 5,800 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30307D at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30307D mean?", "a": "Suffix reading on 30307D: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30307D", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30307d", "4t-30307d", "7fb", "30307D" ], "locale_variants": {} }, { "sku": "32307-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32307", "series": "32300-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 80, "B_mm": 32.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 112, "static_load_kN": 115, "limiting_speed_rpm": 5000, "max_rpm": 5000, "speed_oil_rpm": 6600, "weight_g": 782, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32307 denotes the extra-heavy 32300 family of metric tapered roller bearings, 35 mm bore, 80 mm outside diameter and 32.75 mm assembled width T (1.378 × 3.15 × 1.289 in) to the ISO 355 boundary plan. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32307 by the metric ISO 355 number (ISO series abbreviation 2FE): 35 mm bore, 80 mm OD. At 112 kN C the bearing offers about 3.2 kN of dynamic capacity per millimetre of the 35 mm bore — compare any substitution on this ratio and the 32.75 mm assembled T, not on bore alone. Catalogue mass of the 32307 set is 782 g (0.031 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Open 4T bearings need application seals; without them the grease at the cone rib of 32307 washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32307.", "The extra-heavy 32300 family at 35 mm bore (80×32.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 6,600 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 32.75 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (32.75 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Open 32307 units have no seals: a wheel-hub or gearbox application needs external sealing or the 5,000 r/min grease figure is meaningless once water reaches the cone rib.", "The 112/115 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32307 (ISO 355 2FE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32307?", "a": "32307 is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 80 mm outside diameter and 32.75 mm assembled width T (1.378 × 3.15 × 1.289 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 112 kN, C0 115 kN (2203E prints no Pu for this size), grease limiting speed 5,000 r/min, oil speed 6,600 r/min, mass about 782 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32307?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32307); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32307 designation encode the 35 mm bore and what is 2FE?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 32.75 mm assembled T follow the ISO 355 dimension-series plan. 2FE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32307 list two speeds, 5,000 and 6,600 r/min?", "a": "The lower figure, 5,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32307 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32307 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32307", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fe", "4t-32307", "32307", "32307-NTN" ], "locale_variants": {} }, { "sku": "32307C", "brand": "NTN", "manufacturer_designation": "NTN 32307C", "series": "32300-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 80, "B_mm": 32.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 103, "static_load_kN": 117, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 804, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 35 mm shaft with a thrust component, NTN lists 32307C, a metric 4T tapered roller bearing of 103 kN C and 117 kN C0 inside the 80 mm OD, 32.75 mm-wide assembled set. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32307C resolves to 35 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Suffix reading on 32307C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles. Imperial cross-check for the drawing: 35×80×32.75 mm is 1.378 × 3.15 × 1.289 in; ISO 355 makes the envelope interchangeable but C/C0, 103/117 kN, is NTN-specific. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 35 mm pair is misadjusted and the 32.75 mm T set will edge-load in service.", "applications": [ "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32307C.", "The extra-heavy 32300 family at 35 mm bore (80×32.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 6,400 r/min oil ceiling.", "Grease packs must leave free volume in the 32.75 mm-wide set; over-greasing a paired bearing churning at the 6,400 r/min oil-band speed raises temperature and destroys the preload setting.", "The 22.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32307C or the ring will bottom out on the radius instead of the shoulder face.", "ISO 355 makes the 35×80 mm envelope interchangeable but not the ratings: NTN prints 103/117 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 103/117 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32307C (ISO 355 5FE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32307C?", "a": "32307C is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 80 mm outside diameter and 32.75 mm assembled width T (1.378 × 3.15 × 1.289 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 103 kN, C0 117 kN (2203E prints no Pu for this size), grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 804 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32307C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32307C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32307C designation encode the 35 mm bore and what is 5FE?", "a": "last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 32.75 mm assembled T follow the ISO 355 dimension-series plan. 5FE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32307C list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32307C at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32307C mean?", "a": "Suffix reading on 32307C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32307C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32307c", "4t-32307c", "5fe", "32307C" ], "locale_variants": {} }, { "sku": "32908XU", "brand": "NTN", "manufacturer_designation": "NTN 32908XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 62, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 36, "static_load_kN": 48, "fatigue_load_limit_kN": 5.85, "limiting_speed_rpm": 5900, "max_rpm": 5900, "speed_oil_rpm": 7800, "weight_g": 161, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32908XU is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 40×62 mm ISO 355 envelope, with 15 mm overall assembled width T. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 40 mm; 62 mm OD and 15 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. Suffix reading on 32908XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. The two speed columns differ by a factor of .76 (grease/limiting 5,900 vs oil 7,800 r/min); heat generation at the cone rib decides which lubrication a real 32908XU arrangement can sustain. Mount the 40 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32908XU.", "applications": [ "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32908XU.", "The thin 15 mm section of 32908XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 40 mm bore smears the roller ends against the rib.", "ISO 355 makes the 40×62 mm envelope interchangeable but not the ratings: NTN prints 36/48 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 40 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "ISO 355 makes the 40×62 mm envelope interchangeable but not the ratings: NTN prints 36/48 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 36/48 kN ratings and 5.85 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32908XU (ISO 355 2BC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32908XU?", "a": "32908XU is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 62 mm outside diameter and 15 mm assembled width T (1.575 × 2.441 × 0.591 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 36 kN, C0 48 kN, Pu 5.85 kN, grease limiting speed 5,900 r/min, oil speed 7,800 r/min, mass about 161 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32908XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32908XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32908XU designation encode the 40 mm bore and what is 2BC?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 62 mm OD and 15 mm assembled T follow the ISO 355 dimension-series plan. 2BC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32908XU list two speeds, 5,900 and 7,800 r/min?", "a": "The lower figure, 5,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32908XU at 7,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32908XU mean?", "a": "Suffix reading on 32908XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32908XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bc", "32908xu", "32908XU" ], "locale_variants": {} }, { "sku": "32008X", "brand": "NTN", "manufacturer_designation": "NTN 32008X", "series": "32000-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 68, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 55.5, "static_load_kN": 65.5, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7100, "weight_g": 272, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32008X is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 40×68 mm ISO 355 envelope, with 19 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32008X by the metric ISO 355 number (ISO series abbreviation 3CD): 40 mm bore, 68 mm OD. The printed contact-angle geometry gives the low-section 32000 family tuned for low friction its characteristic load split — at 55.5/65.5 kN (C/C0) the static rating is about 1.18× C, typical of tapered bearings proportioned for heavy combined duty. The 1.4 kN-per-mm-bore capacity figure for 32008X summarises the 55.5 kN rating over 40 mm bore; use it to sanity-check an interchange candidate before swapping brands. Mount the 40 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32008X.", "applications": [ "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32008X.", "The thin 19 mm section of 32008X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 40 mm bore smears the roller ends against the rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 40 mm shoulder geometry, because retrofitting flips the cups.", "Never fit the 40 mm cone by hammering the 68 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Minimum load matters at high speed: an unloaded 32008X at a large fraction of 5,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 55.5/65.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32008X (ISO 355 3CD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32008X?", "a": "32008X is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 68 mm outside diameter and 19 mm assembled width T (1.575 × 2.677 × 0.748 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 55.5 kN, C0 65.5 kN (2203E prints no Pu for this size), grease limiting speed 5,300 r/min, oil speed 7,100 r/min, mass about 272 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32008X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32008X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32008X designation encode the 40 mm bore and what is 3CD?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 68 mm OD and 19 mm assembled T follow the ISO 355 dimension-series plan. 3CD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32008X list two speeds, 5,300 and 7,100 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32008X at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32008X mean?", "a": "Suffix reading on 32008X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32008X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32008x", "3cd", "4t-32008x", "32008X" ], "locale_variants": {} }, { "sku": "33008", "brand": "NTN", "manufacturer_designation": "NTN 33008", "series": "33000-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 68, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 66, "static_load_kN": 82.5, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7100, "weight_g": 320, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 40 mm shaft with a thrust component, NTN lists 33008, a metric 4T tapered roller bearing of 66 kN C and 82.5 kN C0 inside the 68 mm OD, 22 mm-wide assembled set. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 33008 resolves to 40 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Individually mounted, 33008 takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Catalogue mass of the 33008 set is 320 g (0.013 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. When pairing 33008 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33008.", "The thin 22 mm section of 33008 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 40 mm bore smears the roller ends against the rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 40 mm shoulder geometry, because retrofitting flips the cups.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 40 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Never fit the 40 mm cone by hammering the 68 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 66/82.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33008 (ISO 355 2BE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33008?", "a": "33008 is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 68 mm outside diameter and 22 mm assembled width T (1.575 × 2.677 × 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 66 kN, C0 82.5 kN (2203E prints no Pu for this size), grease limiting speed 5,300 r/min, oil speed 7,100 r/min, mass about 320 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33008?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33008); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33008 designation encode the 40 mm bore and what is 2BE?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 68 mm OD and 22 mm assembled T follow the ISO 355 dimension-series plan. 2BE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33008 list two speeds, 5,300 and 7,100 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33008 at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33008 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33008", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2be", "4t-33008", "33008" ], "locale_variants": {} }, { "sku": "33108-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33108", "series": "33100-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 75, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 88, "static_load_kN": 103, "limiting_speed_rpm": 5200, "max_rpm": 5200, "speed_oil_rpm": 6900, "weight_g": 498, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 40 mm bore tapered roller position as 33108: one cone assembly, one cup, line-contact rollers and a steel cage, rated 88 kN basic dynamic and 103 kN static on the light-wide 33100 family. The last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 26 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 33108, not only the raceway. Grease relubrication at 5,200 r/min limiting speed targets the rib contact; if the drive needs 6,900 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 40 mm pair is misadjusted and the 26 mm T set will edge-load in service.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33108.", "The light-wide 33100 family at 40 mm bore (75×26 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 6,900 r/min oil ceiling.", "The 17.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33108 or the ring will bottom out on the radius instead of the shoulder face.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33108 by size alone can deliver the wrong contact-angle execution for a pinion position.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 40 mm shoulder geometry, because retrofitting flips the cups.", "The 88/103 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33108 (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33108?", "a": "33108 is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 75 mm outside diameter and 26 mm assembled width T (1.575 × 2.953 × 1.024 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 88 kN, C0 103 kN (2203E prints no Pu for this size), grease limiting speed 5,200 r/min, oil speed 6,900 r/min, mass about 498 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33108?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33108); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33108 designation encode the 40 mm bore and what is 2CE?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 75 mm OD and 26 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33108 list two speeds, 5,200 and 6,900 r/min?", "a": "The lower figure, 5,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33108 at 6,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33108 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33108", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "33108-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "4t-33108", "33108", "33108-NTN" ], "locale_variants": {} }, { "sku": "30208-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30208", "series": "30200-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 19.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 68, "static_load_kN": 67, "limiting_speed_rpm": 4900, "max_rpm": 4900, "speed_oil_rpm": 6600, "weight_g": 431, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30208 in the standard-section 30200 family: 40 mm bore, 80 mm cup OD, 19.75 mm T, with a grease limiting speed of 4,900 r/min and an oil-lubricated ceiling of 6,600 r/min. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3DB, which is the maker-neutral cross-reference for the 40×80 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 30208 cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Catalogue mass of the 30208 set is 431 g (0.017 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 40 mm pair is misadjusted and the 19.75 mm T set will edge-load in service.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30208.", "The standard-section 30200 family at 40 mm bore (80×19.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 6,600 r/min oil ceiling.", "Do not confuse T (19.75 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 19.75 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (19.75 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 68/67 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30208 (ISO 355 3DB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30208?", "a": "30208 is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 80 mm outside diameter and 19.75 mm assembled width T (1.575 × 3.15 × 0.778 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 68 kN, C0 67 kN (2203E prints no Pu for this size), grease limiting speed 4,900 r/min, oil speed 6,600 r/min, mass about 431 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30208?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30208); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30208 designation encode the 40 mm bore and what is 3DB?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 19.75 mm assembled T follow the ISO 355 dimension-series plan. 3DB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30208 list two speeds, 4,900 and 6,600 r/min?", "a": "The lower figure, 4,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30208 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30208 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30208", "equiv_brand": "SKF", "level": "partial", "note": "Same 40×80×19.75 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "30208-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3db", "4t-30208", "30208", "30208-NTN" ], "locale_variants": {} }, { "sku": "32208-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32208", "series": "32200-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 24.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 88, "static_load_kN": 93.5, "limiting_speed_rpm": 4900, "max_rpm": 4900, "speed_oil_rpm": 6600, "weight_g": 547, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32208 denotes the heavy-section 32200 family of metric tapered roller bearings, 40 mm bore, 80 mm outside diameter and 24.75 mm assembled width T (1.575 × 3.15 × 0.974 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the heavy-section 32200 family and a bore code resolving to 40 mm; 80 mm OD and 24.75 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Selection: C 88 kN against C0 93.5 kN gives a C0/C ratio of 1.06 for the 40 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 32208 washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32208.", "The heavy-section 32200 family at 40 mm bore (80×24.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 6,600 r/min oil ceiling.", "Never fit the 40 mm cone by hammering the 80 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never fit the 40 mm cone by hammering the 80 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Replacing one half of an adjusted pair without resetting end play negates the 24.75 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 88/93.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32208 (ISO 355 3DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32208?", "a": "32208 is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 80 mm outside diameter and 24.75 mm assembled width T (1.575 × 3.15 × 0.974 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 88 kN, C0 93.5 kN (2203E prints no Pu for this size), grease limiting speed 4,900 r/min, oil speed 6,600 r/min, mass about 547 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32208?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32208); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32208 designation encode the 40 mm bore and what is 3DC?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 24.75 mm assembled T follow the ISO 355 dimension-series plan. 3DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32208 list two speeds, 4,900 and 6,600 r/min?", "a": "The lower figure, 4,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32208 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32208 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32208", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32208-SKF", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3dc", "4t-32208", "32208", "32208-NTN" ], "locale_variants": {} }, { "sku": "33208-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33208", "series": "33200-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 115, "static_load_kN": 132, "limiting_speed_rpm": 4900, "max_rpm": 4900, "speed_oil_rpm": 6600, "weight_g": 738, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33208 is the NTN 4T catalogue entry for a 40×80×32 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 33208 by the metric ISO 355 number (ISO series abbreviation 2DE): 40 mm bore, 80 mm OD. At 115 kN C the bearing offers about 2.9 kN of dynamic capacity per millimetre of the 40 mm bore — compare any substitution on this ratio and the 32 mm assembled T, not on bore alone. Imperial cross-check for the drawing: 40×80×32 mm is 1.575 × 3.15 × 1.26 in; ISO 355 makes the envelope interchangeable but C/C0, 115/132 kN, is NTN-specific. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 40 mm pair is misadjusted and the 32 mm T set will edge-load in service.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33208.", "The medium-wide 33200 family at 40 mm bore (80×32 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 6,600 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 32 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 40 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Open 33208 units have no seals: a wheel-hub or gearbox application needs external sealing or the 4,900 r/min grease figure is meaningless once water reaches the cone rib.", "The 115/132 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33208 (ISO 355 2DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33208?", "a": "33208 is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 80 mm outside diameter and 32 mm assembled width T (1.575 × 3.15 × 1.26 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 115 kN, C0 132 kN (2203E prints no Pu for this size), grease limiting speed 4,900 r/min, oil speed 6,600 r/min, mass about 738 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33208?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33208); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33208 designation encode the 40 mm bore and what is 2DE?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 32 mm assembled T follow the ISO 355 dimension-series plan. 2DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33208 list two speeds, 4,900 and 6,600 r/min?", "a": "The lower figure, 4,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33208 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33208 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33208", "equiv_brand": "SKF", "level": "partial", "note": "Same 40×80×32 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2de", "4t-33208", "33208", "33208-NTN" ], "locale_variants": {} }, { "sku": "T2EE040", "brand": "NTN", "manufacturer_designation": "NTN T2EE040", "series": "T2EE-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 85, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 131, "static_load_kN": 144, "limiting_speed_rpm": 4600, "max_rpm": 4600, "speed_oil_rpm": 6200, "weight_g": 905, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 40 mm bore tapered roller position as T2EE040: one cone assembly, one cup, line-contact rollers and a steel cage, rated 131 kN basic dynamic and 144 kN static on the large-size ISO 355 tapered-roller family. Digit by digit, the bare number identifies the large-size ISO 355 tapered-roller family and a bore code resolving to 40 mm; 85 mm OD and 33 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The 22.5 mm radial section carries the roller complement across the 40–85 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The two speed columns differ by a factor of .74 (grease/limiting 4,600 vs oil 6,200 r/min); heat generation at the cone rib decides which lubrication a real T2EE040 arrangement can sustain. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 40 mm pair is misadjusted and the 33 mm T set will edge-load in service.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on T2EE040.", "The large-size ISO 355 tapered-roller family at 40 mm bore (85×33 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 6,200 r/min oil ceiling.", "Open T2EE040 units have no seals: a wheel-hub or gearbox application needs external sealing or the 4,600 r/min grease figure is meaningless once water reaches the cone rib.", "Grease packs must leave free volume in the 33 mm-wide set; over-greasing a paired bearing churning at the 6,200 r/min oil-band speed raises temperature and destroys the preload setting.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering T2EE040 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 131/144 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T2EE040 (ISO 355 2EE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T2EE040?", "a": "T2EE040 is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 85 mm outside diameter and 33 mm assembled width T (1.575 × 3.346 × 1.299 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 131 kN, C0 144 kN (2203E prints no Pu for this size), grease limiting speed 4,600 r/min, oil speed 6,200 r/min, mass about 905 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T2EE040?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T2EE040); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T2EE040 designation encode the 40 mm bore and what is 2EE?", "a": "trailing dimension block 040 prints the 40 mm bore directly for this large-size T-code. The 85 mm OD and 33 mm assembled T follow the ISO 355 dimension-series plan. 2EE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T2EE040 list two speeds, 4,600 and 6,200 r/min?", "a": "The lower figure, 4,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T2EE040 at 6,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T2EE040 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 40 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T2EE040", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ee", "4t-t2ee040", "t2ee040", "T2EE040" ], "locale_variants": {} }, { "sku": "30308-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30308", "series": "30300-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 90, "B_mm": 25.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 101, "static_load_kN": 102, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5900, "weight_g": 765, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 40 mm shaft with a thrust component, NTN lists 30308, a metric 4T tapered roller bearing of 101 kN C and 102 kN C0 inside the 90 mm OD, 25.25 mm-wide assembled set. The last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 25.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Grease relubrication at 4,400 r/min limiting speed targets the rib contact; if the drive needs 5,900 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 40 mm pair is misadjusted and the 25.25 mm T set will edge-load in service.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30308.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 40 mm bore; do not swap to the lighter family without re-checking the 4,400 r/min grease limit and the thrust load split.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 40 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Open 30308 units have no seals: a wheel-hub or gearbox application needs external sealing or the 4,400 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 25.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 101/102 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30308 (ISO 355 2FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30308?", "a": "30308 is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 90 mm outside diameter and 25.25 mm assembled width T (1.575 × 3.543 × 0.994 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 101 kN, C0 102 kN (2203E prints no Pu for this size), grease limiting speed 4,400 r/min, oil speed 5,900 r/min, mass about 765 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30308?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30308); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30308 designation encode the 40 mm bore and what is 2FB?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 90 mm OD and 25.25 mm assembled T follow the ISO 355 dimension-series plan. 2FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30308 list two speeds, 4,400 and 5,900 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30308 at 5,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30308 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30308", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fb", "4t-30308", "30308", "30308-NTN" ], "locale_variants": {} }, { "sku": "30308C", "brand": "NTN", "manufacturer_designation": "NTN 30308C", "series": "30300-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 90, "B_mm": 25.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 92, "static_load_kN": 87, "limiting_speed_rpm": 4200, "max_rpm": 4200, "speed_oil_rpm": 5600, "weight_g": 726, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30308C belongs to the NTN metric 4T tapered roller range (large-OD 30300 family with the steeper contact angle); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 40×90 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. Suffix reading on 30308C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles. Speed planning uses both catalogue columns: grease 4,200 r/min is the cage/rib mechanical ceiling for 30308C, oil 5,600 r/min is available with circulating oil — a 1,400 r/min margin at this size. Open 4T bearings need application seals; without them the grease at the cone rib of 30308C washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30308C.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 40 mm bore; do not swap to the lighter family without re-checking the 4,200 r/min grease limit and the thrust load split.", "The 25.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30308C or the ring will bottom out on the radius instead of the shoulder face.", "Never fit the 40 mm cone by hammering the 90 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ISO 355 makes the 40×90 mm envelope interchangeable but not the ratings: NTN prints 92/87 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 92/87 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30308C; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30308C?", "a": "30308C is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 90 mm outside diameter and 25.25 mm assembled width T (1.575 × 3.543 × 0.994 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 92 kN, C0 87 kN (2203E prints no Pu for this size), grease limiting speed 4,200 r/min, oil speed 5,600 r/min, mass about 726 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30308C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30308C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30308C designation encode the 40 mm bore?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 90 mm OD and 25.25 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30308C list two speeds, 4,200 and 5,600 r/min?", "a": "The lower figure, 4,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30308C at 5,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30308C mean?", "a": "Suffix reading on 30308C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30308C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30308c", "4t-30308c", "30308C" ], "locale_variants": {} }, { "sku": "30308D", "brand": "NTN", "manufacturer_designation": "NTN 30308D", "series": "30300-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 90, "B_mm": 25.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85.5, "static_load_kN": 85.5, "limiting_speed_rpm": 3900, "max_rpm": 3900, "speed_oil_rpm": 5200, "weight_g": 727, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30308D is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 40×90 mm ISO 355 envelope, with 25.25 mm overall assembled width T. Digit by digit, the bare number identifies the large-OD 30300 family with the steeper contact angle and a bore code resolving to 40 mm; 90 mm OD and 25.25 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 30308D, since running clearance is set during assembly. The two speed columns differ by a factor of .75 (grease/limiting 3,900 vs oil 5,200 r/min); heat generation at the cone rib decides which lubrication a real 30308D arrangement can sustain. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 40 mm pair is misadjusted and the 25.25 mm T set will edge-load in service.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30308D.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 40 mm bore; do not swap to the lighter family without re-checking the 3,900 r/min grease limit and the thrust load split.", "Grease packs must leave free volume in the 25.25 mm-wide set; over-greasing a paired bearing churning at the 5,200 r/min oil-band speed raises temperature and destroys the preload setting.", "Replacing one half of an adjusted pair without resetting end play negates the 25.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 40 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 85.5/85.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30308D (ISO 355 7FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30308D?", "a": "30308D is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 90 mm outside diameter and 25.25 mm assembled width T (1.575 × 3.543 × 0.994 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85.5 kN, C0 85.5 kN (2203E prints no Pu for this size), grease limiting speed 3,900 r/min, oil speed 5,200 r/min, mass about 727 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30308D?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30308D); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30308D designation encode the 40 mm bore and what is 7FB?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 90 mm OD and 25.25 mm assembled T follow the ISO 355 dimension-series plan. 7FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30308D list two speeds, 3,900 and 5,200 r/min?", "a": "The lower figure, 3,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30308D at 5,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30308D mean?", "a": "Suffix reading on 30308D: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30308D", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30308d", "4t-30308d", "7fb", "30308D" ], "locale_variants": {} }, { "sku": "32308C", "brand": "NTN", "manufacturer_designation": "NTN 32308C", "series": "32300-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 90, "B_mm": 35.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 122, "static_load_kN": 140, "limiting_speed_rpm": 4200, "max_rpm": 4200, "speed_oil_rpm": 5600, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32308C denotes the extra-heavy 32300 family of metric tapered roller bearings, 40 mm bore, 90 mm outside diameter and 35.25 mm assembled width T (1.575 × 3.543 × 1.388 in) to the ISO 355 boundary plan. The last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 35.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. NTN grades 4T metric bearings as open bearings without integral seals; at 40 mm bore the application supplies the seals and the grease fill or oil supply to the 5FD ISO 355 assembly. The two speed columns differ by a factor of .75 (grease/limiting 4,200 vs oil 5,600 r/min); heat generation at the cone rib decides which lubrication a real 32308C arrangement can sustain. Open 4T bearings need application seals; without them the grease at the cone rib of 32308C washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32308C.", "The extra-heavy 32300 family at 40 mm bore (90×35.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,600 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 40 mm shoulder geometry, because retrofitting flips the cups.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 40 mm shoulder geometry, because retrofitting flips the cups.", "The 25.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32308C or the ring will bottom out on the radius instead of the shoulder face.", "The 122/140 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32308C (ISO 355 5FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32308C?", "a": "32308C is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 90 mm outside diameter and 35.25 mm assembled width T (1.575 × 3.543 × 1.388 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 122 kN, C0 140 kN (2203E prints no Pu for this size), grease limiting speed 4,200 r/min, oil speed 5,600 r/min, mass about 1100 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32308C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32308C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32308C designation encode the 40 mm bore and what is 5FD?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 90 mm OD and 35.25 mm assembled T follow the ISO 355 dimension-series plan. 5FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32308C list two speeds, 4,200 and 5,600 r/min?", "a": "The lower figure, 4,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32308C at 5,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32308C mean?", "a": "Suffix reading on 32308C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32308C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32308c", "4t-32308c", "5fd", "32308C" ], "locale_variants": {} }, { "sku": "32308U", "brand": "NTN", "manufacturer_designation": "NTN 32308U", "series": "32300-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 90, "B_mm": 35.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 136, "static_load_kN": 150, "fatigue_load_limit_kN": 18.3, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5900, "weight_g": 1080, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 40 mm shaft with a thrust component, NTN lists 32308U, a metric 4T tapered roller bearing of 136 kN C and 150 kN C0 inside the 90 mm OD, 35.25 mm-wide assembled set. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32308U resolves to 40 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Individually mounted, 32308U takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The two speed columns differ by a factor of .75 (grease/limiting 4,400 vs oil 5,900 r/min); heat generation at the cone rib decides which lubrication a real 32308U arrangement can sustain. Fillet radii must clear the ring chamfers of the 90 mm cup and 40 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion bearings of this 40 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32308U.", "The extra-heavy 32300 family at 40 mm bore (90×35.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,900 r/min oil ceiling.", "Grease packs must leave free volume in the 35.25 mm-wide set; over-greasing a paired bearing churning at the 5,900 r/min oil-band speed raises temperature and destroys the preload setting.", "Replacing one half of an adjusted pair without resetting end play negates the 35.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never fit the 40 mm cone by hammering the 90 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 136/150 kN ratings and 18.3 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32308U (ISO 355 2FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32308U?", "a": "32308U is a metric 4T tapered roller bearing to ISO 355: 40 mm bore, 90 mm outside diameter and 35.25 mm assembled width T (1.575 × 3.543 × 1.388 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 136 kN, C0 150 kN, Pu 18.3 kN, grease limiting speed 4,400 r/min, oil speed 5,900 r/min, mass about 1080 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32308U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32308U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32308U designation encode the 40 mm bore and what is 2FD?", "a": "last two digits 08 are the ISO bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table). The 90 mm OD and 35.25 mm assembled T follow the ISO 355 dimension-series plan. 2FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32308U list two speeds, 4,400 and 5,900 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32308U at 5,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32308U mean?", "a": "Suffix reading on 32308U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32308U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fd", "32308u", "32308U" ], "locale_variants": {} }, { "sku": "32909XU", "brand": "NTN", "manufacturer_designation": "NTN 32909XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 68, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 37.5, "static_load_kN": 51.5, "fatigue_load_limit_kN": 6.3, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7000, "weight_g": 187, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 45 mm bore tapered roller position as 32909XU: one cone assembly, one cup, line-contact rollers and a steel cage, rated 37.5 kN basic dynamic and 51.5 kN static on the extra-light thin-section 32900 family. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2BC, which is the maker-neutral cross-reference for the 45×68 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. At 37.5 kN C the bearing offers about 0.8 kN of dynamic capacity per millimetre of the 45 mm bore — compare any substitution on this ratio and the 15 mm assembled T, not on bore alone. Catalogue mass of the 32909XU set is 187 g (0.007 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Mount the 45 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32909XU.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32909XU.", "The thin 15 mm section of 32909XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 45 mm bore smears the roller ends against the rib.", "Open 32909XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 5,300 r/min grease figure is meaningless once water reaches the cone rib.", "Never fit the 45 mm cone by hammering the 68 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 32909XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 5,300 r/min grease figure is meaningless once water reaches the cone rib.", "The 37.5/51.5 kN ratings and 6.3 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32909XU (ISO 355 2BC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32909XU?", "a": "32909XU is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 68 mm outside diameter and 15 mm assembled width T (1.772 × 2.677 × 0.591 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 37.5 kN, C0 51.5 kN, Pu 6.3 kN, grease limiting speed 5,300 r/min, oil speed 7,000 r/min, mass about 187 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32909XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32909XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32909XU designation encode the 45 mm bore and what is 2BC?", "a": "last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table). The 68 mm OD and 15 mm assembled T follow the ISO 355 dimension-series plan. 2BC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32909XU list two speeds, 5,300 and 7,000 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32909XU at 7,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32909XU mean?", "a": "Suffix reading on 32909XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32909XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=166", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bc", "32909xu", "32909XU" ], "locale_variants": {} }, { "sku": "32009X", "brand": "NTN", "manufacturer_designation": "NTN 32009X", "series": "32000-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 75, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 64, "static_load_kN": 76.5, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 341, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32009X is the NTN 4T catalogue entry for a 45×75×20 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3CC, which is the maker-neutral cross-reference for the 45×75 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32009X, since running clearance is set during assembly. Imperial cross-check for the drawing: 45×75×20 mm is 1.772 × 2.953 × 0.787 in; ISO 355 makes the envelope interchangeable but C/C0, 64/76.5 kN, is NTN-specific. When pairing 32009X with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32009X.", "The thin 20 mm section of 32009X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 45 mm bore smears the roller ends against the rib.", "Open 32009X units have no seals: a wheel-hub or gearbox application needs external sealing or the 4,800 r/min grease figure is meaningless once water reaches the cone rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 45 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 45 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 64/76.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32009X (ISO 355 3CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32009X?", "a": "32009X is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 75 mm outside diameter and 20 mm assembled width T (1.772 × 2.953 × 0.787 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 64 kN, C0 76.5 kN (2203E prints no Pu for this size), grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 341 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32009X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32009X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32009X designation encode the 45 mm bore and what is 3CC?", "a": "last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table). The 75 mm OD and 20 mm assembled T follow the ISO 355 dimension-series plan. 3CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32009X list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32009X at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32009X mean?", "a": "Suffix reading on 32009X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32009X-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32009x", "3cc", "4t-32009x", "32009X" ], "locale_variants": {} }, { "sku": "33009", "brand": "NTN", "manufacturer_designation": "NTN 33009", "series": "33000-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 75, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 73.5, "static_load_kN": 93.5, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 405, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33009 belongs to the NTN metric 4T tapered roller range (slim 33000 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 33009 by the metric ISO 355 number (ISO series abbreviation 2CE): 45 mm bore, 75 mm OD. The printed contact-angle geometry gives the slim 33000 family its characteristic load split — at 73.5/93.5 kN (C/C0) the static rating is about 1.27× C, typical of tapered bearings proportioned for heavy combined duty. Speed planning uses both catalogue columns: grease 4,800 r/min is the cage/rib mechanical ceiling for 33009, oil 6,400 r/min is available with circulating oil — a 1,600 r/min margin at this size. Mount the 45 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 33009.", "applications": [ "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33009.", "The thin 24 mm section of 33009 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 45 mm bore smears the roller ends against the rib.", "Minimum load matters at high speed: an unloaded 33009 at a large fraction of 4,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Never fit the 45 mm cone by hammering the 75 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Minimum load matters at high speed: an unloaded 33009 at a large fraction of 4,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 73.5/93.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33009 (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33009?", "a": "33009 is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 75 mm outside diameter and 24 mm assembled width T (1.772 × 2.953 × 0.945 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 73.5 kN, C0 93.5 kN (2203E prints no Pu for this size), grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 405 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33009?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33009); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33009 designation encode the 45 mm bore and what is 2CE?", "a": "last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table). The 75 mm OD and 24 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33009 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33009 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33009 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33009", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "4t-33009", "33009" ], "locale_variants": {} }, { "sku": "33109-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33109", "series": "33100-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 80, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 94, "static_load_kN": 115, "limiting_speed_rpm": 4700, "max_rpm": 4700, "speed_oil_rpm": 6200, "weight_g": 544, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33109 is the NTN 4T catalogue entry for a 45×80×26 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Digit by digit, the bare number identifies the light-wide 33100 family and a bore code resolving to 45 mm; 80 mm OD and 26 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. The 17.5 mm section height over the 45 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 45 mm pair is misadjusted and the 26 mm T set will edge-load in service.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33109.", "The light-wide 33100 family at 45 mm bore (80×26 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 6,200 r/min oil ceiling.", "Never fit the 45 mm cone by hammering the 80 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 17.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33109 or the ring will bottom out on the radius instead of the shoulder face.", "Replacing one half of an adjusted pair without resetting end play negates the 26 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 94/115 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33109 (ISO 355 3CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33109?", "a": "33109 is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 80 mm outside diameter and 26 mm assembled width T (1.772 × 3.15 × 1.024 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 94 kN, C0 115 kN (2203E prints no Pu for this size), grease limiting speed 4,700 r/min, oil speed 6,200 r/min, mass about 544 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33109?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33109); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33109 designation encode the 45 mm bore and what is 3CE?", "a": "last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 26 mm assembled T follow the ISO 355 dimension-series plan. 3CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33109 list two speeds, 4,700 and 6,200 r/min?", "a": "The lower figure, 4,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33109 at 6,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33109 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33109", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3ce", "4t-33109", "33109", "33109-NTN" ], "locale_variants": {} }, { "sku": "30209-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30209", "series": "30200-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 85, "B_mm": 20.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 75, "static_load_kN": 78.5, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5900, "weight_g": 493, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 45 mm shaft with a thrust component, NTN lists 30209, a metric 4T tapered roller bearing of 75 kN C and 78.5 kN C0 inside the 85 mm OD, 20.75 mm-wide assembled set. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30209 resolves to 45 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Individually mounted, 30209 takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. 2203E does not print a Pu fatigue load limit for 30209; life work for this size uses the 75/78.5 kN C/C0 pair directly. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 45 mm pair is misadjusted and the 20.75 mm T set will edge-load in service.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30209.", "The standard-section 30200 family at 45 mm bore (85×20.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,900 r/min oil ceiling.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30209 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30209 by size alone can deliver the wrong contact-angle execution for a pinion position.", "Never fit the 45 mm cone by hammering the 85 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 75/78.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30209 (ISO 355 3DB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30209?", "a": "30209 is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 85 mm outside diameter and 20.75 mm assembled width T (1.772 × 3.346 × 0.817 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 75 kN, C0 78.5 kN (2203E prints no Pu for this size), grease limiting speed 4,400 r/min, oil speed 5,900 r/min, mass about 493 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30209?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30209); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30209 designation encode the 45 mm bore and what is 3DB?", "a": "last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table). The 85 mm OD and 20.75 mm assembled T follow the ISO 355 dimension-series plan. 3DB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30209 list two speeds, 4,400 and 5,900 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30209 at 5,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30209 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30209", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3db", "4t-30209", "30209", "30209-NTN" ], "locale_variants": {} }, { "sku": "32209-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32209", "series": "32200-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 85, "B_mm": 24.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 91, "static_load_kN": 100, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5900, "weight_g": 604, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 45 mm bore tapered roller position as 32209: one cone assembly, one cup, line-contact rollers and a steel cage, rated 91 kN basic dynamic and 100 kN static on the heavy-section 32200 family. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32209 by the metric ISO 355 number (ISO series abbreviation 3DC): 45 mm bore, 85 mm OD. 2203E lists two speed ceilings for 32209: 4,400 r/min with grease lubrication (the limiting speed) and 5,900 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. The two speed columns differ by a factor of .75 (grease/limiting 4,400 vs oil 5,900 r/min); heat generation at the cone rib decides which lubrication a real 32209 arrangement can sustain. Open 4T bearings need application seals; without them the grease at the cone rib of 32209 washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32209.", "The heavy-section 32200 family at 45 mm bore (85×24.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,900 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 45 mm shoulder geometry, because retrofitting flips the cups.", "Grease packs must leave free volume in the 24.75 mm-wide set; over-greasing a paired bearing churning at the 5,900 r/min oil-band speed raises temperature and destroys the preload setting.", "Grease packs must leave free volume in the 24.75 mm-wide set; over-greasing a paired bearing churning at the 5,900 r/min oil-band speed raises temperature and destroys the preload setting.", "The 91/100 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32209 (ISO 355 3DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32209?", "a": "32209 is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 85 mm outside diameter and 24.75 mm assembled width T (1.772 × 3.346 × 0.974 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 91 kN, C0 100 kN (2203E prints no Pu for this size), grease limiting speed 4,400 r/min, oil speed 5,900 r/min, mass about 604 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32209?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32209); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32209 designation encode the 45 mm bore and what is 3DC?", "a": "last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table). The 85 mm OD and 24.75 mm assembled T follow the ISO 355 dimension-series plan. 3DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32209 list two speeds, 4,400 and 5,900 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32209 at 5,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32209 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32209", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32209-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32209-SKF", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3dc", "4t-32209", "32209", "32209-NTN" ], "locale_variants": {} }, { "sku": "33209-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33209", "series": "33200-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 85, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 119, "static_load_kN": 141, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5900, "weight_g": 795, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 33209 in the medium-wide 33200 family: 45 mm bore, 85 mm cup OD, 32 mm T, with a grease limiting speed of 4,400 r/min and an oil-lubricated ceiling of 5,900 r/min. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3DE, which is the maker-neutral cross-reference for the 45×85 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The 20.0 mm radial section carries the roller complement across the 45–85 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The 2.6 kN-per-mm-bore capacity figure for 33209 summarises the 119 kN rating over 45 mm bore; use it to sanity-check an interchange candidate before swapping brands. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 45 mm pair is misadjusted and the 32 mm T set will edge-load in service.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33209.", "The medium-wide 33200 family at 45 mm bore (85×32 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,900 r/min oil ceiling.", "The 20.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33209 or the ring will bottom out on the radius instead of the shoulder face.", "Minimum load matters at high speed: an unloaded 33209 at a large fraction of 4,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33209 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 119/141 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33209 (ISO 355 3DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33209?", "a": "33209 is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 85 mm outside diameter and 32 mm assembled width T (1.772 × 3.346 × 1.26 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 119 kN, C0 141 kN (2203E prints no Pu for this size), grease limiting speed 4,400 r/min, oil speed 5,900 r/min, mass about 795 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33209?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33209); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33209 designation encode the 45 mm bore and what is 3DE?", "a": "last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table). The 85 mm OD and 32 mm assembled T follow the ISO 355 dimension-series plan. 3DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33209 list two speeds, 4,400 and 5,900 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33209 at 5,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33209 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33209", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3de", "4t-33209", "33209", "33209-NTN" ], "locale_variants": {} }, { "sku": "T7FC045", "brand": "NTN", "manufacturer_designation": "NTN T7FC045", "series": "T7FC-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 95, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 99.5, "static_load_kN": 108, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 907, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number T7FC045 denotes the large-size ISO 355 tapered-roller family of metric tapered roller bearings, 45 mm bore, 95 mm outside diameter and 29 mm assembled width T (1.772 × 3.74 × 1.142 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the large-size ISO 355 tapered-roller family and a bore code resolving to 45 mm; 95 mm OD and 29 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for T7FC045, since running clearance is set during assembly. The 2.2 kN-per-mm-bore capacity figure for T7FC045 summarises the 99.5 kN rating over 45 mm bore; use it to sanity-check an interchange candidate before swapping brands. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 45 mm pair is misadjusted and the 29 mm T set will edge-load in service.", "applications": [ "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on T7FC045.", "The large-size ISO 355 tapered-roller family at 45 mm bore (95×29 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,500 r/min oil ceiling.", "Grease packs must leave free volume in the 29 mm-wide set; over-greasing a paired bearing churning at the 5,500 r/min oil-band speed raises temperature and destroys the preload setting.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 45 mm shoulder geometry, because retrofitting flips the cups.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 45 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 99.5/108 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T7FC045 (ISO 355 7FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T7FC045?", "a": "T7FC045 is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 95 mm outside diameter and 29 mm assembled width T (1.772 × 3.74 × 1.142 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 99.5 kN, C0 108 kN (2203E prints no Pu for this size), grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 907 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T7FC045?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T7FC045); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T7FC045 designation encode the 45 mm bore and what is 7FC?", "a": "trailing dimension block 045 prints the 45 mm bore directly for this large-size T-code. The 95 mm OD and 29 mm assembled T follow the ISO 355 dimension-series plan. 7FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T7FC045 list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T7FC045 at 5,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T7FC045 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 45 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T7FC045", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-t7fc045", "7fc", "t7fc045", "T7FC045" ], "locale_variants": {} }, { "sku": "30309-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30309", "series": "30300-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 100, "B_mm": 27.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 123, "static_load_kN": 126, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 1010, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30309 belongs to the NTN metric 4T tapered roller range (large-OD 30300 family with the steeper contact angle); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Digit by digit, the bare number identifies the large-OD 30300 family with the steeper contact angle and a bore code resolving to 45 mm; 100 mm OD and 27.25 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. 2203E lists two speed ceilings for 30309: 4,000 r/min with grease lubrication (the limiting speed) and 5,300 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. The 27.5 mm section height over the 45 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 45 mm pair is misadjusted and the 27.25 mm T set will edge-load in service.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30309.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 45 mm bore; do not swap to the lighter family without re-checking the 4,000 r/min grease limit and the thrust load split.", "Do not confuse T (27.25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 45 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Grease packs must leave free volume in the 27.25 mm-wide set; over-greasing a paired bearing churning at the 5,300 r/min oil-band speed raises temperature and destroys the preload setting.", "The 123/126 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30309 (ISO 355 2FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30309?", "a": "30309 is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 100 mm outside diameter and 27.25 mm assembled width T (1.772 × 3.937 × 1.073 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 123 kN, C0 126 kN (2203E prints no Pu for this size), grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 1010 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30309?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30309); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30309 designation encode the 45 mm bore and what is 2FB?", "a": "last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table). The 100 mm OD and 27.25 mm assembled T follow the ISO 355 dimension-series plan. 2FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30309 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30309 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30309 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30309", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "30309-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fb", "4t-30309", "30309", "30309-NTN" ], "locale_variants": {} }, { "sku": "30309D", "brand": "NTN", "manufacturer_designation": "NTN 30309D", "series": "30300-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 100, "B_mm": 27.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 106, "static_load_kN": 109, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4600, "weight_g": 966, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30309D is the NTN 4T catalogue entry for a 45×100×27.25 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30309D by the metric ISO 355 number (ISO series abbreviation 7FB): 45 mm bore, 100 mm OD. At 106 kN C the bearing offers about 2.4 kN of dynamic capacity per millimetre of the 45 mm bore — compare any substitution on this ratio and the 27.25 mm assembled T, not on bore alone. Selection: C 106 kN against C0 109 kN gives a C0/C ratio of 1.03 for the 45 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 30309D washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30309D.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 45 mm bore; do not swap to the lighter family without re-checking the 3,500 r/min grease limit and the thrust load split.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 45 mm shoulder geometry, because retrofitting flips the cups.", "Never fit the 45 mm cone by hammering the 100 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 30309D units have no seals: a wheel-hub or gearbox application needs external sealing or the 3,500 r/min grease figure is meaningless once water reaches the cone rib.", "The 106/109 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30309D (ISO 355 7FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30309D?", "a": "30309D is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 100 mm outside diameter and 27.25 mm assembled width T (1.772 × 3.937 × 1.073 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 106 kN, C0 109 kN (2203E prints no Pu for this size), grease limiting speed 3,500 r/min, oil speed 4,600 r/min, mass about 966 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30309D?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30309D); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30309D designation encode the 45 mm bore and what is 7FB?", "a": "last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table). The 100 mm OD and 27.25 mm assembled T follow the ISO 355 dimension-series plan. 7FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30309D list two speeds, 3,500 and 4,600 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30309D at 4,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30309D mean?", "a": "Suffix reading on 30309D: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30309D", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30309d", "4t-30309d", "7fb", "30309D" ], "locale_variants": {} }, { "sku": "32309CU", "brand": "NTN", "manufacturer_designation": "NTN 32309CU", "series": "32300-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 100, "B_mm": 38.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 145, "static_load_kN": 175, "fatigue_load_limit_kN": 21.4, "limiting_speed_rpm": 3800, "max_rpm": 3800, "speed_oil_rpm": 5100, "weight_g": 1470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32309CU is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 45×100 mm ISO 355 envelope, with 38.25 mm overall assembled width T. The last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 38.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32309CU cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The 27.5 mm section height over the 45 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 32309CU; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32309CU.", "The extra-heavy 32300 family at 45 mm bore (100×38.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,100 r/min oil ceiling.", "Grease packs must leave free volume in the 38.25 mm-wide set; over-greasing a paired bearing churning at the 5,100 r/min oil-band speed raises temperature and destroys the preload setting.", "The 27.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32309CU or the ring will bottom out on the radius instead of the shoulder face.", "Do not confuse T (38.25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 145/175 kN ratings and 21.4 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32309CU (ISO 355 5FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32309CU?", "a": "32309CU is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 100 mm outside diameter and 38.25 mm assembled width T (1.772 × 3.937 × 1.506 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 145 kN, C0 175 kN, Pu 21.4 kN, grease limiting speed 3,800 r/min, oil speed 5,100 r/min, mass about 1470 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32309CU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32309CU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32309CU designation encode the 45 mm bore and what is 5FD?", "a": "last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table). The 100 mm OD and 38.25 mm assembled T follow the ISO 355 dimension-series plan. 5FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32309CU list two speeds, 3,800 and 5,100 r/min?", "a": "The lower figure, 3,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32309CU at 5,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32309CU mean?", "a": "Suffix reading on 32309CU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32309CU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32309cu", "5fd", "32309CU" ], "locale_variants": {} }, { "sku": "32309U", "brand": "NTN", "manufacturer_designation": "NTN 32309U", "series": "32300-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 100, "B_mm": 38.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 170, "static_load_kN": 191, "fatigue_load_limit_kN": 23.3, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32309U denotes the extra-heavy 32300 family of metric tapered roller bearings, 45 mm bore, 100 mm outside diameter and 38.25 mm assembled width T (1.772 × 3.937 × 1.506 in) to the ISO 355 boundary plan. The last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 38.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Suffix reading on 32309U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. Selection: C 170 kN against C0 191 kN gives a C0/C ratio of 1.12 for the 45 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32309U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 45 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32309U.", "The extra-heavy 32300 family at 45 mm bore (100×38.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,300 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 45 mm shoulder geometry, because retrofitting flips the cups.", "Never fit the 45 mm cone by hammering the 100 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ISO 355 makes the 45×100 mm envelope interchangeable but not the ratings: NTN prints 170/191 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 170/191 kN ratings and 23.3 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32309U (ISO 355 2FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32309U?", "a": "32309U is a metric 4T tapered roller bearing to ISO 355: 45 mm bore, 100 mm outside diameter and 38.25 mm assembled width T (1.772 × 3.937 × 1.506 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 170 kN, C0 191 kN, Pu 23.3 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 1450 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32309U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32309U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32309U designation encode the 45 mm bore and what is 2FD?", "a": "last two digits 09 are the ISO bore code, ×5 = 45 mm (codes 00–03 use the 10/12/15/17 exception table). The 100 mm OD and 38.25 mm assembled T follow the ISO 355 dimension-series plan. 2FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32309U list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32309U at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32309U mean?", "a": "Suffix reading on 32309U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32309U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fd", "32309u", "32309U" ], "locale_variants": {} }, { "sku": "32910", "brand": "NTN", "manufacturer_designation": "NTN 32910", "series": "32900-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 72, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 35, "static_load_kN": 50.5, "fatigue_load_limit_kN": 6.15, "limiting_speed_rpm": 4700, "max_rpm": 4700, "speed_oil_rpm": 6300, "weight_g": 193, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32910 denotes the extra-light thin-section 32900 family of metric tapered roller bearings, 50 mm bore, 72 mm outside diameter and 15 mm assembled width T (1.969 × 2.835 × 0.591 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 50×72 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. At 35 kN C the bearing offers about 0.7 kN of dynamic capacity per millimetre of the 50 mm bore — compare any substitution on this ratio and the 15 mm assembled T, not on bore alone. Selection: C 35 kN against C0 50.5 kN gives a C0/C ratio of 1.44 for the 50 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32910 arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32910.", "The thin 15 mm section of 32910 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 50 mm bore smears the roller ends against the rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 50 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 11.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32910 or the ring will bottom out on the radius instead of the shoulder face.", "Open 32910 units have no seals: a wheel-hub or gearbox application needs external sealing or the 4,700 r/min grease figure is meaningless once water reaches the cone rib.", "The 35/50.5 kN ratings and 6.15 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32910; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32910?", "a": "32910 is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 72 mm outside diameter and 15 mm assembled width T (1.969 × 2.835 × 0.591 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 35 kN, C0 50.5 kN, Pu 6.15 kN, grease limiting speed 4,700 r/min, oil speed 6,300 r/min, mass about 193 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32910?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32910); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32910 designation encode the 50 mm bore?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 72 mm OD and 15 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32910 list two speeds, 4,700 and 6,300 r/min?", "a": "The lower figure, 4,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32910 at 6,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32910 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32910", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "○32910", "32910" ], "locale_variants": {} }, { "sku": "32910XU", "brand": "NTN", "manufacturer_designation": "NTN 32910XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 72, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 39.5, "static_load_kN": 57, "fatigue_load_limit_kN": 6.95, "limiting_speed_rpm": 4700, "max_rpm": 4700, "speed_oil_rpm": 6300, "weight_g": 192, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32910XU denotes the extra-light thin-section 32900 family of metric tapered roller bearings, 50 mm bore, 72 mm outside diameter and 15 mm assembled width T (1.969 × 2.835 × 0.591 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 50 mm; 72 mm OD and 15 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. 2203E lists two speed ceilings for 32910XU: 4,700 r/min with grease lubrication (the limiting speed) and 6,300 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. The 11.0 mm section height over the 50 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32910XU arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32910XU.", "The thin 15 mm section of 32910XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 50 mm bore smears the roller ends against the rib.", "Never fit the 50 mm cone by hammering the 72 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Minimum load matters at high speed: an unloaded 32910XU at a large fraction of 4,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Grease packs must leave free volume in the 15 mm-wide set; over-greasing a paired bearing churning at the 6,300 r/min oil-band speed raises temperature and destroys the preload setting.", "The 39.5/57 kN ratings and 6.95 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32910XU (ISO 355 2BC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32910XU?", "a": "32910XU is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 72 mm outside diameter and 15 mm assembled width T (1.969 × 2.835 × 0.591 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 39.5 kN, C0 57 kN, Pu 6.95 kN, grease limiting speed 4,700 r/min, oil speed 6,300 r/min, mass about 192 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32910XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32910XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32910XU designation encode the 50 mm bore and what is 2BC?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 72 mm OD and 15 mm assembled T follow the ISO 355 dimension-series plan. 2BC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32910XU list two speeds, 4,700 and 6,300 r/min?", "a": "The lower figure, 4,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32910XU at 6,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32910XU mean?", "a": "Suffix reading on 32910XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32910XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bc", "32910xu", "32910XU" ], "locale_variants": {} }, { "sku": "32010X", "brand": "NTN", "manufacturer_designation": "NTN 32010X", "series": "32000-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 80, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 69.5, "static_load_kN": 88, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5800, "weight_g": 373, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32010X belongs to the NTN metric 4T tapered roller range (low-section 32000 family tuned for low friction); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. The last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 20 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32010X, since running clearance is set during assembly. The two speed columns differ by a factor of .76 (grease/limiting 4,400 vs oil 5,800 r/min); heat generation at the cone rib decides which lubrication a real 32010X arrangement can sustain. Fillet radii must clear the ring chamfers of the 80 mm cup and 50 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32010X.", "The thin 20 mm section of 32010X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 50 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 20 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 50 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 50 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 69.5/88 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32010X (ISO 355 3CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32010X?", "a": "32010X is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 80 mm outside diameter and 20 mm assembled width T (1.969 × 3.15 × 0.787 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 69.5 kN, C0 88 kN (2203E prints no Pu for this size), grease limiting speed 4,400 r/min, oil speed 5,800 r/min, mass about 373 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32010X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32010X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32010X designation encode the 50 mm bore and what is 3CC?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 20 mm assembled T follow the ISO 355 dimension-series plan. 3CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32010X list two speeds, 4,400 and 5,800 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32010X at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32010X mean?", "a": "Suffix reading on 32010X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32010X-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32010x", "3cc", "4t-32010x", "32010X" ], "locale_variants": {} }, { "sku": "33010-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33010", "series": "33000-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 80, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 77.5, "static_load_kN": 103, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5800, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 33010 denotes the slim 33000 family of metric tapered roller bearings, 50 mm bore, 80 mm outside diameter and 24 mm assembled width T (1.969 × 3.15 × 0.945 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the slim 33000 family and a bore code resolving to 50 mm; 80 mm OD and 24 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 33010 cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The two speed columns differ by a factor of .76 (grease/limiting 4,400 vs oil 5,800 r/min); heat generation at the cone rib decides which lubrication a real 33010 arrangement can sustain. When pairing 33010 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33010.", "The thin 24 mm section of 33010 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 50 mm bore smears the roller ends against the rib.", "Never fit the 50 mm cone by hammering the 80 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ISO 355 makes the 50×80 mm envelope interchangeable but not the ratings: NTN prints 77.5/103 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Do not confuse T (24 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 77.5/103 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33010 (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33010?", "a": "33010 is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 80 mm outside diameter and 24 mm assembled width T (1.969 × 3.15 × 0.945 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 103 kN (2203E prints no Pu for this size), grease limiting speed 4,400 r/min, oil speed 5,800 r/min, mass about 440 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33010?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33010); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33010 designation encode the 50 mm bore and what is 2CE?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 24 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33010 list two speeds, 4,400 and 5,800 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33010 at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33010 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33010", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "33010-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "4t-33010", "33010", "33010-NTN" ], "locale_variants": {} }, { "sku": "33110-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33110", "series": "33100-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 85, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 96, "static_load_kN": 121, "limiting_speed_rpm": 4200, "max_rpm": 4200, "speed_oil_rpm": 5600, "weight_g": 583, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33110 is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 50×85 mm ISO 355 envelope, with 26 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3CE, which is the maker-neutral cross-reference for the 50×85 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. With no letter after the number, 33110 is the basic open 4T execution: steel cage, normal adjustment, no seal or special internal-design suffix in the order code. Selection: C 96 kN against C0 121 kN gives a C0/C ratio of 1.26 for the 50 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Fillet radii must clear the ring chamfers of the 85 mm cup and 50 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33110.", "The light-wide 33100 family at 50 mm bore (85×26 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,600 r/min oil ceiling.", "The 17.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33110 or the ring will bottom out on the radius instead of the shoulder face.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 50 mm shoulder geometry, because retrofitting flips the cups.", "ISO 355 makes the 50×85 mm envelope interchangeable but not the ratings: NTN prints 96/121 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 96/121 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33110 (ISO 355 3CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33110?", "a": "33110 is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 85 mm outside diameter and 26 mm assembled width T (1.969 × 3.346 × 1.024 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 96 kN, C0 121 kN (2203E prints no Pu for this size), grease limiting speed 4,200 r/min, oil speed 5,600 r/min, mass about 583 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33110?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33110); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33110 designation encode the 50 mm bore and what is 3CE?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 85 mm OD and 26 mm assembled T follow the ISO 355 dimension-series plan. 3CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33110 list two speeds, 4,200 and 5,600 r/min?", "a": "The lower figure, 4,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33110 at 5,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33110 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33110", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3ce", "4t-33110", "33110", "33110-NTN" ], "locale_variants": {} }, { "sku": "30210-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30210", "series": "30200-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 90, "B_mm": 21.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85.5, "static_load_kN": 93, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 560, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 50 mm bore tapered roller position as 30210: one cone assembly, one cup, line-contact rollers and a steel cage, rated 85.5 kN basic dynamic and 93 kN static on the standard-section 30200 family. Digit by digit, the bare number identifies the standard-section 30200 family and a bore code resolving to 50 mm; 90 mm OD and 21.75 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The printed contact-angle geometry gives the standard-section 30200 family its characteristic load split — at 85.5/93 kN (C/C0) the static rating is about 1.09× C, typical of tapered bearings proportioned for heavy combined duty. The two speed columns differ by a factor of .75 (grease/limiting 4,000 vs oil 5,300 r/min); heat generation at the cone rib decides which lubrication a real 30210 arrangement can sustain. Open 4T bearings need application seals; without them the grease at the cone rib of 30210 washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30210.", "The standard-section 30200 family at 50 mm bore (90×21.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,300 r/min oil ceiling.", "Do not confuse T (21.75 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Minimum load matters at high speed: an unloaded 30210 at a large fraction of 4,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Minimum load matters at high speed: an unloaded 30210 at a large fraction of 4,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 85.5/93 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30210 (ISO 355 3DB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30210?", "a": "30210 is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 90 mm outside diameter and 21.75 mm assembled width T (1.969 × 3.543 × 0.856 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85.5 kN, C0 93 kN (2203E prints no Pu for this size), grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 560 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30210?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30210); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30210 designation encode the 50 mm bore and what is 3DB?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 90 mm OD and 21.75 mm assembled T follow the ISO 355 dimension-series plan. 3DB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30210 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30210 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30210 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30210", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "30210-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3db", "4t-30210", "30210", "30210-NTN" ], "locale_variants": {} }, { "sku": "32210-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32210", "series": "32200-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 90, "B_mm": 24.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 97, "static_load_kN": 109, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 639, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32210 belongs to the NTN metric 4T tapered roller range (heavy-section 32200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32210 resolves to 50 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32210 cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Grease relubrication at 4,000 r/min limiting speed targets the rib contact; if the drive needs 5,300 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Mount the 50 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32210.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32210.", "The heavy-section 32200 family at 50 mm bore (90×24.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,300 r/min oil ceiling.", "Never fit the 50 mm cone by hammering the 90 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 20.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32210 or the ring will bottom out on the radius instead of the shoulder face.", "Do not confuse T (24.75 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 97/109 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32210 (ISO 355 3DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32210?", "a": "32210 is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 90 mm outside diameter and 24.75 mm assembled width T (1.969 × 3.543 × 0.974 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 97 kN, C0 109 kN (2203E prints no Pu for this size), grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 639 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32210?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32210); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32210 designation encode the 50 mm bore and what is 3DC?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 90 mm OD and 24.75 mm assembled T follow the ISO 355 dimension-series plan. 3DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32210 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32210 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32210 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32210", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32210-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32210-SKF", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3dc", "4t-32210", "32210", "32210-NTN" ], "locale_variants": {} }, { "sku": "33210-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33210", "series": "33200-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 90, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 127, "static_load_kN": 158, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 862, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 33210 denotes the medium-wide 33200 family of metric tapered roller bearings, 50 mm bore, 90 mm outside diameter and 32 mm assembled width T (1.969 × 3.543 × 1.26 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the medium-wide 33200 family and a bore code resolving to 50 mm; 90 mm OD and 32 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. Individually mounted, 33210 takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The 20.0 mm section height over the 50 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Fillet radii must clear the ring chamfers of the 90 mm cup and 50 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33210.", "The medium-wide 33200 family at 50 mm bore (90×32 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,300 r/min oil ceiling.", "The 20.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33210 or the ring will bottom out on the radius instead of the shoulder face.", "The 20.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33210 or the ring will bottom out on the radius instead of the shoulder face.", "Never fit the 50 mm cone by hammering the 90 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 127/158 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33210 (ISO 355 3DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33210?", "a": "33210 is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 90 mm outside diameter and 32 mm assembled width T (1.969 × 3.543 × 1.26 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 127 kN, C0 158 kN (2203E prints no Pu for this size), grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 862 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33210?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33210); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33210 designation encode the 50 mm bore and what is 3DE?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 90 mm OD and 32 mm assembled T follow the ISO 355 dimension-series plan. 3DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33210 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33210 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33210 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33210", "equiv_brand": "SKF", "level": "partial", "note": "Same 50×90×32 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "33210-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3de", "4t-33210", "33210", "33210-NTN" ], "locale_variants": {} }, { "sku": "T2ED050", "brand": "NTN", "manufacturer_designation": "NTN T2ED050", "series": "T2ED-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 100, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 167, "static_load_kN": 190, "limiting_speed_rpm": 3800, "max_rpm": 3800, "speed_oil_rpm": 5100, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "T2ED050 is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 50×100 mm ISO 355 envelope, with 36 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2ED, which is the maker-neutral cross-reference for the 50×100 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The 25.0 mm radial section carries the roller complement across the 50–100 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Imperial cross-check for the drawing: 50×100×36 mm is 1.969 × 3.937 × 1.417 in; ISO 355 makes the envelope interchangeable but C/C0, 167/190 kN, is NTN-specific. Re-adjustment after bedding-in is standard practice: re-check end play once the paired T2ED050 arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on T2ED050.", "The large-size ISO 355 tapered-roller family at 50 mm bore (100×36 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,100 r/min oil ceiling.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering T2ED050 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering T2ED050 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering T2ED050 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 167/190 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T2ED050 (ISO 355 2ED); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T2ED050?", "a": "T2ED050 is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 100 mm outside diameter and 36 mm assembled width T (1.969 × 3.937 × 1.417 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 167 kN, C0 190 kN (2203E prints no Pu for this size), grease limiting speed 3,800 r/min, oil speed 5,100 r/min, mass about 1300 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T2ED050?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T2ED050); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T2ED050 designation encode the 50 mm bore and what is 2ED?", "a": "trailing dimension block 050 prints the 50 mm bore directly for this large-size T-code. The 100 mm OD and 36 mm assembled T follow the ISO 355 dimension-series plan. 2ED is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T2ED050 list two speeds, 3,800 and 5,100 r/min?", "a": "The lower figure, 3,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T2ED050 at 5,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T2ED050 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 50 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T2ED050", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ed", "4t-t2ed050", "t2ed050", "T2ED050" ], "locale_variants": {} }, { "sku": "T7FC050", "brand": "NTN", "manufacturer_designation": "NTN T7FC050", "series": "T7FC-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 105, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 119, "static_load_kN": 132, "limiting_speed_rpm": 3400, "max_rpm": 3400, "speed_oil_rpm": 4500, "weight_g": 1220, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "T7FC050 belongs to the NTN metric 4T tapered roller range (large-size ISO 355 tapered-roller family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders T7FC050 by the metric ISO 355 number (ISO series abbreviation 7FC): 50 mm bore, 105 mm OD. Individually mounted, T7FC050 takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The two speed columns differ by a factor of .76 (grease/limiting 3,400 vs oil 4,500 r/min); heat generation at the cone rib decides which lubrication a real T7FC050 arrangement can sustain. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for T7FC050; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on T7FC050.", "The large-size ISO 355 tapered-roller family at 50 mm bore (105×32 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,500 r/min oil ceiling.", "The 27.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for T7FC050 or the ring will bottom out on the radius instead of the shoulder face.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 50 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Never fit the 50 mm cone by hammering the 105 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 119/132 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T7FC050 (ISO 355 7FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T7FC050?", "a": "T7FC050 is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 105 mm outside diameter and 32 mm assembled width T (1.969 × 4.134 × 1.26 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 119 kN, C0 132 kN (2203E prints no Pu for this size), grease limiting speed 3,400 r/min, oil speed 4,500 r/min, mass about 1220 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T7FC050?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T7FC050); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T7FC050 designation encode the 50 mm bore and what is 7FC?", "a": "trailing dimension block 050 prints the 50 mm bore directly for this large-size T-code. The 105 mm OD and 32 mm assembled T follow the ISO 355 dimension-series plan. 7FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T7FC050 list two speeds, 3,400 and 4,500 r/min?", "a": "The lower figure, 3,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T7FC050 at 4,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T7FC050 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 50 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T7FC050", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-t7fc050", "7fc", "t7fc050", "T7FC050" ], "locale_variants": {} }, { "sku": "30310-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30310", "series": "30300-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 110, "B_mm": 29.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 147, "static_load_kN": 152, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 1310, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30310 is the NTN 4T catalogue entry for a 50×110×29.25 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2FB, which is the maker-neutral cross-reference for the 50×110 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 30310, since running clearance is set during assembly. Selection: C 147 kN against C0 152 kN gives a C0/C ratio of 1.03 for the 50 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Fillet radii must clear the ring chamfers of the 110 mm cup and 50 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30310.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 50 mm bore; do not swap to the lighter family without re-checking the 3,600 r/min grease limit and the thrust load split.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 50 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30310 by size alone can deliver the wrong contact-angle execution for a pinion position.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 50 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 147/152 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30310 (ISO 355 2FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30310?", "a": "30310 is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 110 mm outside diameter and 29.25 mm assembled width T (1.969 × 4.331 × 1.152 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 147 kN, C0 152 kN (2203E prints no Pu for this size), grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1310 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30310?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30310); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30310 designation encode the 50 mm bore and what is 2FB?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 29.25 mm assembled T follow the ISO 355 dimension-series plan. 2FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30310 list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30310 at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30310 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30310", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fb", "4t-30310", "30310", "30310-NTN" ], "locale_variants": {} }, { "sku": "30310D", "brand": "NTN", "manufacturer_designation": "NTN 30310D", "series": "30300-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 110, "B_mm": 29.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 126, "static_load_kN": 130, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 30310D denotes the large-OD 30300 family with the steeper contact angle of metric tapered roller bearings, 50 mm bore, 110 mm outside diameter and 29.25 mm assembled width T (1.969 × 4.331 × 1.152 in) to the ISO 355 boundary plan. The last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 29.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Individually mounted, 30310D takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The 30.0 mm section height over the 50 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Open 4T bearings need application seals; without them the grease at the cone rib of 30310D washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30310D.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 50 mm bore; do not swap to the lighter family without re-checking the 3,200 r/min grease limit and the thrust load split.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30310D by size alone can deliver the wrong contact-angle execution for a pinion position.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 50 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Never fit the 50 mm cone by hammering the 110 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 126/130 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30310D (ISO 355 7FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30310D?", "a": "30310D is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 110 mm outside diameter and 29.25 mm assembled width T (1.969 × 4.331 × 1.152 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 126 kN, C0 130 kN (2203E prints no Pu for this size), grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1250 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30310D?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30310D); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30310D designation encode the 50 mm bore and what is 7FB?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 29.25 mm assembled T follow the ISO 355 dimension-series plan. 7FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30310D list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30310D at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30310D mean?", "a": "Suffix reading on 30310D: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30310D", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30310d", "4t-30310d", "7fb", "30310D" ], "locale_variants": {} }, { "sku": "32310C", "brand": "NTN", "manufacturer_designation": "NTN 32310C", "series": "32300-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 110, "B_mm": 42.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 178, "static_load_kN": 220, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4600, "weight_g": 1970, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32310C is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 50×110 mm ISO 355 envelope, with 42.25 mm overall assembled width T. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32310C resolves to 50 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Suffix reading on 32310C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles. The 30.0 mm section height over the 50 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 50 mm pair is misadjusted and the 42.25 mm T set will edge-load in service.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32310C.", "The extra-heavy 32300 family at 50 mm bore (110×42.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,600 r/min oil ceiling.", "The 30.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32310C or the ring will bottom out on the radius instead of the shoulder face.", "ISO 355 makes the 50×110 mm envelope interchangeable but not the ratings: NTN prints 178/220 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "ISO 355 makes the 50×110 mm envelope interchangeable but not the ratings: NTN prints 178/220 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 178/220 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32310C (ISO 355 5FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32310C?", "a": "32310C is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 110 mm outside diameter and 42.25 mm assembled width T (1.969 × 4.331 × 1.663 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 178 kN, C0 220 kN (2203E prints no Pu for this size), grease limiting speed 3,500 r/min, oil speed 4,600 r/min, mass about 1970 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32310C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32310C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32310C designation encode the 50 mm bore and what is 5FD?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 42.25 mm assembled T follow the ISO 355 dimension-series plan. 5FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32310C list two speeds, 3,500 and 4,600 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32310C at 4,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32310C mean?", "a": "Suffix reading on 32310C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32310C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32310c", "4t-32310c", "5fd", "32310C" ], "locale_variants": {} }, { "sku": "32310U", "brand": "NTN", "manufacturer_designation": "NTN 32310U", "series": "32300-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 110, "B_mm": 42.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 204, "static_load_kN": 232, "fatigue_load_limit_kN": 28.3, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 1920, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32310U in the extra-heavy 32300 family: 50 mm bore, 110 mm cup OD, 42.25 mm T, with a grease limiting speed of 3,600 r/min and an oil-lubricated ceiling of 4,800 r/min. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2FD, which is the maker-neutral cross-reference for the 50×110 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. 2203E lists two speed ceilings for 32310U: 3,600 r/min with grease lubrication (the limiting speed) and 4,800 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. The 30.0 mm section height over the 50 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. When pairing 32310U with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 50 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32310U.", "The extra-heavy 32300 family at 50 mm bore (110×42.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,800 r/min oil ceiling.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32310U by size alone can deliver the wrong contact-angle execution for a pinion position.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 50 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Grease packs must leave free volume in the 42.25 mm-wide set; over-greasing a paired bearing churning at the 4,800 r/min oil-band speed raises temperature and destroys the preload setting.", "The 204/232 kN ratings and 28.3 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32310U (ISO 355 2FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32310U?", "a": "32310U is a metric 4T tapered roller bearing to ISO 355: 50 mm bore, 110 mm outside diameter and 42.25 mm assembled width T (1.969 × 4.331 × 1.663 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 204 kN, C0 232 kN, Pu 28.3 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1920 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32310U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32310U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32310U designation encode the 50 mm bore and what is 2FD?", "a": "last two digits 10 are the ISO bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 42.25 mm assembled T follow the ISO 355 dimension-series plan. 2FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32310U list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32310U at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32310U mean?", "a": "Suffix reading on 32310U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32310U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fd", "32310u", "32310U" ], "locale_variants": {} }, { "sku": "32911XU", "brand": "NTN", "manufacturer_designation": "NTN 32911XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 80, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 49.5, "static_load_kN": 73.5, "fatigue_load_limit_kN": 8.95, "limiting_speed_rpm": 4300, "max_rpm": 4300, "speed_oil_rpm": 5700, "weight_g": 274, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32911XU is the NTN 4T catalogue entry for a 55×80×17 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2BC, which is the maker-neutral cross-reference for the 55×80 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The printed contact-angle geometry gives the extra-light thin-section 32900 family its characteristic load split — at 49.5/73.5 kN (C/C0) the static rating is about 1.48× C, typical of tapered bearings proportioned for heavy combined duty. The two speed columns differ by a factor of .75 (grease/limiting 4,300 vs oil 5,700 r/min); heat generation at the cone rib decides which lubrication a real 32911XU arrangement can sustain. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32911XU arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32911XU.", "The thin 17 mm section of 32911XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 55 mm bore smears the roller ends against the rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 55 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Grease packs must leave free volume in the 17 mm-wide set; over-greasing a paired bearing churning at the 5,700 r/min oil-band speed raises temperature and destroys the preload setting.", "Minimum load matters at high speed: an unloaded 32911XU at a large fraction of 4,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 49.5/73.5 kN ratings and 8.95 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32911XU (ISO 355 2BC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32911XU?", "a": "32911XU is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 80 mm outside diameter and 17 mm assembled width T (2.165 × 3.15 × 0.669 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 49.5 kN, C0 73.5 kN, Pu 8.95 kN, grease limiting speed 4,300 r/min, oil speed 5,700 r/min, mass about 274 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32911XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32911XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32911XU designation encode the 55 mm bore and what is 2BC?", "a": "last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 17 mm assembled T follow the ISO 355 dimension-series plan. 2BC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32911XU list two speeds, 4,300 and 5,700 r/min?", "a": "The lower figure, 4,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32911XU at 5,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32911XU mean?", "a": "Suffix reading on 32911XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32911XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bc", "32911xu", "32911XU" ], "locale_variants": {} }, { "sku": "32011X", "brand": "NTN", "manufacturer_designation": "NTN 32011X", "series": "32000-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 90, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 89, "static_load_kN": 118, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5400, "weight_g": 560, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 55 mm bore tapered roller position as 32011X: one cone assembly, one cup, line-contact rollers and a steel cage, rated 89 kN basic dynamic and 118 kN static on the low-section 32000 family tuned for low friction. Digit by digit, the bare number identifies the low-section 32000 family tuned for low friction and a bore code resolving to 55 mm; 90 mm OD and 23 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. At 89 kN C the bearing offers about 1.6 kN of dynamic capacity per millimetre of the 55 mm bore — compare any substitution on this ratio and the 23 mm assembled T, not on bore alone. Selection: C 89 kN against C0 118 kN gives a C0/C ratio of 1.33 for the 55 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32011X arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32011X.", "The thin 23 mm section of 32011X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 55 mm bore smears the roller ends against the rib.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32011X by size alone can deliver the wrong contact-angle execution for a pinion position.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32011X by size alone can deliver the wrong contact-angle execution for a pinion position.", "Open 32011X units have no seals: a wheel-hub or gearbox application needs external sealing or the 4,000 r/min grease figure is meaningless once water reaches the cone rib.", "The 89/118 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32011X (ISO 355 3CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32011X?", "a": "32011X is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 90 mm outside diameter and 23 mm assembled width T (2.165 × 3.543 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 89 kN, C0 118 kN (2203E prints no Pu for this size), grease limiting speed 4,000 r/min, oil speed 5,400 r/min, mass about 560 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32011X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32011X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32011X designation encode the 55 mm bore and what is 3CC?", "a": "last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table). The 90 mm OD and 23 mm assembled T follow the ISO 355 dimension-series plan. 3CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32011X list two speeds, 4,000 and 5,400 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32011X at 5,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32011X mean?", "a": "Suffix reading on 32011X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32011X-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32011x", "3cc", "4t-32011x", "32011X" ], "locale_variants": {} }, { "sku": "33011-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33011", "series": "33000-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 90, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 102, "static_load_kN": 138, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5400, "weight_g": 654, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33011 is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 55×90 mm ISO 355 envelope, with 27 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2CE, which is the maker-neutral cross-reference for the 55×90 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The printed contact-angle geometry gives the slim 33000 family its characteristic load split — at 102/138 kN (C/C0) the static rating is about 1.35× C, typical of tapered bearings proportioned for heavy combined duty. Selection: C 102 kN against C0 138 kN gives a C0/C ratio of 1.35 for the 55 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 33011 washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs", "truck and bus wheel hubs in paired arrangements" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33011.", "The thin 27 mm section of 33011 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 55 mm bore smears the roller ends against the rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 55 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Never fit the 55 mm cone by hammering the 90 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Minimum load matters at high speed: an unloaded 33011 at a large fraction of 4,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 102/138 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33011 (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33011?", "a": "33011 is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 90 mm outside diameter and 27 mm assembled width T (2.165 × 3.543 × 1.063 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 102 kN, C0 138 kN (2203E prints no Pu for this size), grease limiting speed 4,000 r/min, oil speed 5,400 r/min, mass about 654 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33011?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33011); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33011 designation encode the 55 mm bore and what is 2CE?", "a": "last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table). The 90 mm OD and 27 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33011 list two speeds, 4,000 and 5,400 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33011 at 5,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33011 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33011", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "33011-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "4t-33011", "33011", "33011-NTN" ], "locale_variants": {} }, { "sku": "33111-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33111", "series": "33100-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 95, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 123, "static_load_kN": 155, "limiting_speed_rpm": 3900, "max_rpm": 3900, "speed_oil_rpm": 5200, "weight_g": 858, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 33111 denotes the light-wide 33100 family of metric tapered roller bearings, 55 mm bore, 95 mm outside diameter and 30 mm assembled width T (2.165 × 3.74 × 1.181 in) to the ISO 355 boundary plan. The last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 30 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 33111, since running clearance is set during assembly. Speed planning uses both catalogue columns: grease 3,900 r/min is the cage/rib mechanical ceiling for 33111, oil 5,200 r/min is available with circulating oil — a 1,300 r/min margin at this size. Fillet radii must clear the ring chamfers of the 95 mm cup and 55 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33111.", "The light-wide 33100 family at 55 mm bore (95×30 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 5,200 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 55 mm shoulder geometry, because retrofitting flips the cups.", "Open 33111 units have no seals: a wheel-hub or gearbox application needs external sealing or the 3,900 r/min grease figure is meaningless once water reaches the cone rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 55 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 123/155 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33111 (ISO 355 3CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33111?", "a": "33111 is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 95 mm outside diameter and 30 mm assembled width T (2.165 × 3.74 × 1.181 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 123 kN, C0 155 kN (2203E prints no Pu for this size), grease limiting speed 3,900 r/min, oil speed 5,200 r/min, mass about 858 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33111?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33111); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33111 designation encode the 55 mm bore and what is 3CE?", "a": "last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table). The 95 mm OD and 30 mm assembled T follow the ISO 355 dimension-series plan. 3CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33111 list two speeds, 3,900 and 5,200 r/min?", "a": "The lower figure, 3,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33111 at 5,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33111 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33111", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3ce", "4t-33111", "33111", "33111-NTN" ], "locale_variants": {} }, { "sku": "30211-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30211", "series": "30200-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 100, "B_mm": 22.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 103, "static_load_kN": 111, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4900, "weight_g": 725, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30211 is the NTN 4T catalogue entry for a 55×100×22.75 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30211 by the metric ISO 355 number (ISO series abbreviation 3DB): 55 mm bore, 100 mm OD. With no letter after the number, 30211 is the basic open 4T execution: steel cage, normal adjustment, no seal or special internal-design suffix in the order code. Imperial cross-check for the drawing: 55×100×22.75 mm is 2.165 × 3.937 × 0.896 in; ISO 355 makes the envelope interchangeable but C/C0, 103/111 kN, is NTN-specific. Open 4T bearings need application seals; without them the grease at the cone rib of 30211 washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30211.", "The standard-section 30200 family at 55 mm bore (100×22.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,900 r/min oil ceiling.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30211 by size alone can deliver the wrong contact-angle execution for a pinion position.", "Do not confuse T (22.75 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "ISO 355 makes the 55×100 mm envelope interchangeable but not the ratings: NTN prints 103/111 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 103/111 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30211 (ISO 355 3DB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30211?", "a": "30211 is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 100 mm outside diameter and 22.75 mm assembled width T (2.165 × 3.937 × 0.896 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 103 kN, C0 111 kN (2203E prints no Pu for this size), grease limiting speed 3,600 r/min, oil speed 4,900 r/min, mass about 725 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30211?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30211); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30211 designation encode the 55 mm bore and what is 3DB?", "a": "last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table). The 100 mm OD and 22.75 mm assembled T follow the ISO 355 dimension-series plan. 3DB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30211 list two speeds, 3,600 and 4,900 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30211 at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30211 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30211", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "30211-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3db", "4t-30211", "30211", "30211-NTN" ], "locale_variants": {} }, { "sku": "32211-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32211", "series": "32200-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 100, "B_mm": 26.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 120, "static_load_kN": 134, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4900, "weight_g": 873, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32211 is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 55×100 mm ISO 355 envelope, with 26.75 mm overall assembled width T. The last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 26.75 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Individually mounted, 32211 takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The 22.5 mm section height over the 55 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Mount the 55 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32211.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32211.", "The heavy-section 32200 family at 55 mm bore (100×26.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,900 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 55 mm shoulder geometry, because retrofitting flips the cups.", "ISO 355 makes the 55×100 mm envelope interchangeable but not the ratings: NTN prints 120/134 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Never fit the 55 mm cone by hammering the 100 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 120/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32211 (ISO 355 3DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32211?", "a": "32211 is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 100 mm outside diameter and 26.75 mm assembled width T (2.165 × 3.937 × 1.053 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 120 kN, C0 134 kN (2203E prints no Pu for this size), grease limiting speed 3,600 r/min, oil speed 4,900 r/min, mass about 873 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32211?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32211); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32211 designation encode the 55 mm bore and what is 3DC?", "a": "last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table). The 100 mm OD and 26.75 mm assembled T follow the ISO 355 dimension-series plan. 3DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32211 list two speeds, 3,600 and 4,900 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32211 at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32211 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32211", "equiv_brand": "FAG", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "32211-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "32211-SKF", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3dc", "4t-32211", "32211", "32211-NTN" ], "locale_variants": {} }, { "sku": "33211-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33211", "series": "33200-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 100, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 188, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4900, "weight_g": 1170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 55 mm bore tapered roller position as 33211: one cone assembly, one cup, line-contact rollers and a steel cage, rated 153 kN basic dynamic and 188 kN static on the medium-wide 33200 family. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 33211 by the metric ISO 355 number (ISO series abbreviation 3DE): 55 mm bore, 100 mm OD. The printed contact-angle geometry gives the medium-wide 33200 family its characteristic load split — at 153/188 kN (C/C0) the static rating is about 1.23× C, typical of tapered bearings proportioned for heavy combined duty. Catalogue mass of the 33211 set is 1170 g (0.046 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Fillet radii must clear the ring chamfers of the 100 mm cup and 55 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 33211.", "The medium-wide 33200 family at 55 mm bore (100×35 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,900 r/min oil ceiling.", "Never fit the 55 mm cone by hammering the 100 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ISO 355 makes the 55×100 mm envelope interchangeable but not the ratings: NTN prints 153/188 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Minimum load matters at high speed: an unloaded 33211 at a large fraction of 3,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 153/188 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33211 (ISO 355 3DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33211?", "a": "33211 is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 100 mm outside diameter and 35 mm assembled width T (2.165 × 3.937 × 1.378 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 188 kN (2203E prints no Pu for this size), grease limiting speed 3,600 r/min, oil speed 4,900 r/min, mass about 1170 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33211?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33211); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33211 designation encode the 55 mm bore and what is 3DE?", "a": "last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table). The 100 mm OD and 35 mm assembled T follow the ISO 355 dimension-series plan. 3DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33211 list two speeds, 3,600 and 4,900 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33211 at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33211 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33211", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3de", "4t-33211", "33211", "33211-NTN" ], "locale_variants": {} }, { "sku": "T7FC055", "brand": "NTN", "manufacturer_designation": "NTN T7FC055", "series": "T7FC-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 115, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 137, "static_load_kN": 156, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4400, "weight_g": 1570, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints T7FC055 in the large-size ISO 355 tapered-roller family: 55 mm bore, 115 mm cup OD, 34 mm T, with a grease limiting speed of 3,300 r/min and an oil-lubricated ceiling of 4,400 r/min. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders T7FC055 by the metric ISO 355 number (ISO series abbreviation 7FC): 55 mm bore, 115 mm OD. At 137 kN C the bearing offers about 2.5 kN of dynamic capacity per millimetre of the 55 mm bore — compare any substitution on this ratio and the 34 mm assembled T, not on bore alone. Imperial cross-check for the drawing: 55×115×34 mm is 2.165 × 4.528 × 1.339 in; ISO 355 makes the envelope interchangeable but C/C0, 137/156 kN, is NTN-specific. Open 4T bearings need application seals; without them the grease at the cone rib of T7FC055 washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on T7FC055.", "The large-size ISO 355 tapered-roller family at 55 mm bore (115×34 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,400 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 55 mm shoulder geometry, because retrofitting flips the cups.", "Do not confuse T (34 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Open T7FC055 units have no seals: a wheel-hub or gearbox application needs external sealing or the 3,300 r/min grease figure is meaningless once water reaches the cone rib.", "The 137/156 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T7FC055 (ISO 355 7FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T7FC055?", "a": "T7FC055 is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 115 mm outside diameter and 34 mm assembled width T (2.165 × 4.528 × 1.339 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 137 kN, C0 156 kN (2203E prints no Pu for this size), grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 1570 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T7FC055?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T7FC055); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T7FC055 designation encode the 55 mm bore and what is 7FC?", "a": "trailing dimension block 055 prints the 55 mm bore directly for this large-size T-code. The 115 mm OD and 34 mm assembled T follow the ISO 355 dimension-series plan. 7FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T7FC055 list two speeds, 3,300 and 4,400 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T7FC055 at 4,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T7FC055 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 55 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T7FC055", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-t7fc055", "7fc", "t7fc055", "T7FC055" ], "locale_variants": {} }, { "sku": "30311-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30311", "series": "30300-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 120, "B_mm": 31.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 172, "static_load_kN": 179, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4400, "weight_g": 1650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 55 mm bore tapered roller position as 30311: one cone assembly, one cup, line-contact rollers and a steel cage, rated 172 kN basic dynamic and 179 kN static on the large-OD 30300 family with the steeper contact angle. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30311 resolves to 55 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. At 172 kN C the bearing offers about 3.1 kN of dynamic capacity per millimetre of the 55 mm bore — compare any substitution on this ratio and the 31.5 mm assembled T, not on bore alone. The two speed columns differ by a factor of .75 (grease/limiting 3,300 vs oil 4,400 r/min); heat generation at the cone rib decides which lubrication a real 30311 arrangement can sustain. Mount the 55 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30311.", "applications": [ "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30311.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 55 mm bore; do not swap to the lighter family without re-checking the 3,300 r/min grease limit and the thrust load split.", "Do not confuse T (31.5 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 32.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30311 or the ring will bottom out on the radius instead of the shoulder face.", "Open 30311 units have no seals: a wheel-hub or gearbox application needs external sealing or the 3,300 r/min grease figure is meaningless once water reaches the cone rib.", "The 172/179 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30311 (ISO 355 2FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30311?", "a": "30311 is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 120 mm outside diameter and 31.5 mm assembled width T (2.165 × 4.724 × 1.24 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 172 kN, C0 179 kN (2203E prints no Pu for this size), grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 1650 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30311?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30311); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30311 designation encode the 55 mm bore and what is 2FB?", "a": "last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table). The 120 mm OD and 31.5 mm assembled T follow the ISO 355 dimension-series plan. 2FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30311 list two speeds, 3,300 and 4,400 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30311 at 4,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30311 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30311", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "30311-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fb", "4t-30311", "30311", "30311-NTN" ], "locale_variants": {} }, { "sku": "30311D", "brand": "NTN", "manufacturer_designation": "NTN 30311D", "series": "30300-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 120, "B_mm": 31.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 146, "static_load_kN": 154, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 1580, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30311D in the large-OD 30300 family with the steeper contact angle: 55 mm bore, 120 mm cup OD, 31.5 mm T, with a grease limiting speed of 2,900 r/min and an oil-lubricated ceiling of 3,800 r/min. Digit by digit, the bare number identifies the large-OD 30300 family with the steeper contact angle and a bore code resolving to 55 mm; 120 mm OD and 31.5 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. Suffix reading on 30311D: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles. Grease relubrication at 2,900 r/min limiting speed targets the rib contact; if the drive needs 3,800 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Mount the 55 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30311D.", "applications": [ "truck and bus wheel hubs in paired arrangements", "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 30311D.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 55 mm bore; do not swap to the lighter family without re-checking the 2,900 r/min grease limit and the thrust load split.", "The 32.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30311D or the ring will bottom out on the radius instead of the shoulder face.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30311D by size alone can deliver the wrong contact-angle execution for a pinion position.", "ISO 355 makes the 55×120 mm envelope interchangeable but not the ratings: NTN prints 146/154 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 146/154 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30311D (ISO 355 7FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30311D?", "a": "30311D is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 120 mm outside diameter and 31.5 mm assembled width T (2.165 × 4.724 × 1.24 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 146 kN, C0 154 kN (2203E prints no Pu for this size), grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 1580 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30311D?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30311D); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30311D designation encode the 55 mm bore and what is 7FB?", "a": "last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table). The 120 mm OD and 31.5 mm assembled T follow the ISO 355 dimension-series plan. 7FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30311D list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30311D at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30311D mean?", "a": "Suffix reading on 30311D: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30311D", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30311d", "4t-30311d", "7fb", "30311D" ], "locale_variants": {} }, { "sku": "32311CU", "brand": "NTN", "manufacturer_designation": "NTN 32311CU", "series": "32300-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 120, "B_mm": 45.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 204, "static_load_kN": 252, "fatigue_load_limit_kN": 30.5, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4200, "weight_g": 2470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32311CU denotes the extra-heavy 32300 family of metric tapered roller bearings, 55 mm bore, 120 mm outside diameter and 45.5 mm assembled width T (2.165 × 4.724 × 1.791 in) to the ISO 355 boundary plan. The last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 45.5 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The 32.5 mm radial section carries the roller complement across the 55–120 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Selection: C 204 kN against C0 252 kN gives a C0/C ratio of 1.24 for the 55 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Mount the 55 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32311CU.", "applications": [ "industrial gearbox and speed-reducer shafts", "bevel and helical pinion drives with high thrust component", "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32311CU.", "The extra-heavy 32300 family at 55 mm bore (120×45.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,200 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 55 mm shoulder geometry, because retrofitting flips the cups.", "ISO 355 makes the 55×120 mm envelope interchangeable but not the ratings: NTN prints 204/252 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32311CU by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 204/252 kN ratings and 30.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32311CU (ISO 355 5FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32311CU?", "a": "32311CU is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 120 mm outside diameter and 45.5 mm assembled width T (2.165 × 4.724 × 1.791 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 204 kN, C0 252 kN, Pu 30.5 kN, grease limiting speed 3,100 r/min, oil speed 4,200 r/min, mass about 2470 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32311CU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32311CU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32311CU designation encode the 55 mm bore and what is 5FD?", "a": "last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table). The 120 mm OD and 45.5 mm assembled T follow the ISO 355 dimension-series plan. 5FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32311CU list two speeds, 3,100 and 4,200 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32311CU at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32311CU mean?", "a": "Suffix reading on 32311CU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32311CU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32311cu", "5fd", "32311CU" ], "locale_variants": {} }, { "sku": "32311U", "brand": "NTN", "manufacturer_designation": "NTN 32311U", "series": "32300-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 120, "B_mm": 45.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 238, "static_load_kN": 275, "fatigue_load_limit_kN": 33.5, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4400, "weight_g": 2440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32311U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 55×120 mm ISO 355 envelope, with 45.5 mm overall assembled width T. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32311U resolves to 55 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Individually mounted, 32311U takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Grease relubrication at 3,300 r/min limiting speed targets the rib contact; if the drive needs 4,400 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Fillet radii must clear the ring chamfers of the 120 mm cup and 55 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "pump and compressor drive shafts carrying combined load", "machine-tool gearbox and headstock shafts", "axle final-drive and differential positions", "construction-equipment wheel and pivot hubs" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion bearings of this 55 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32311U.", "The extra-heavy 32300 family at 55 mm bore (120×45.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,400 r/min oil ceiling.", "The 32.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32311U or the ring will bottom out on the radius instead of the shoulder face.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32311U by size alone can deliver the wrong contact-angle execution for a pinion position.", "Never fit the 55 mm cone by hammering the 120 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 238/275 kN ratings and 33.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32311U (ISO 355 2FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32311U?", "a": "32311U is a metric 4T tapered roller bearing to ISO 355: 55 mm bore, 120 mm outside diameter and 45.5 mm assembled width T (2.165 × 4.724 × 1.791 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 238 kN, C0 275 kN, Pu 33.5 kN, grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 2440 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32311U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32311U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32311U designation encode the 55 mm bore and what is 2FD?", "a": "last two digits 11 are the ISO bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table). The 120 mm OD and 45.5 mm assembled T follow the ISO 355 dimension-series plan. 2FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32311U list two speeds, 3,300 and 4,400 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32311U at 4,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32311U mean?", "a": "Suffix reading on 32311U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32311U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=167", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fd", "32311u", "32311U" ], "locale_variants": {} }, { "sku": "32912XA", "brand": "NTN", "manufacturer_designation": "NTN 32912XA", "series": "32900-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 85, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 56.5, "static_load_kN": 83, "fatigue_load_limit_kN": 10.1, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 281, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32912XA belongs to the NTN metric 4T tapered roller range (extra-light thin-section 32900 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. The last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 17 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32912XA cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The 0.9 kN-per-mm-bore capacity figure for 32912XA summarises the 56.5 kN rating over 60 mm bore; use it to sanity-check an interchange candidate before swapping brands. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 60 mm pair is misadjusted and the 17 mm T set will edge-load in service.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 281 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 17 mm section of 32912XA is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 60 mm bore smears the roller ends against the rib.", "Open 32912XA units have no seals: a wheel-hub or gearbox application needs external sealing or the 4,000 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 17 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (17 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 56.5/83 kN ratings and 10.1 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32912XA; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32912XA?", "a": "32912XA is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 85 mm outside diameter and 17 mm assembled width T (2.362 × 3.346 × 0.669 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 56.5 kN, C0 83 kN, Pu 10.1 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 281 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32912XA?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32912XA); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32912XA designation encode the 60 mm bore?", "a": "last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 85 mm OD and 17 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32912XA list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32912XA at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32912XA mean?", "a": "Suffix reading on 32912XA: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32912XA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32912xa", "○32912xa", "32912XA" ], "locale_variants": {} }, { "sku": "32012X", "brand": "NTN", "manufacturer_designation": "NTN 32012X", "series": "32000-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 95, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 91, "static_load_kN": 123, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 596, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 60 mm shaft with a thrust component, NTN lists 32012X, a metric 4T tapered roller bearing of 91 kN C and 123 kN C0 inside the 95 mm OD, 23 mm-wide assembled set. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32012X by the metric ISO 355 number (ISO series abbreviation 4CC): 60 mm bore, 95 mm OD. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32012X, not only the raceway. Speed planning uses both catalogue columns: grease 3,700 r/min is the cage/rib mechanical ceiling for 32012X, oil 4,900 r/min is available with circulating oil — a 1,200 r/min margin at this size. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 32012X; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 596 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 23 mm section of 32012X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 60 mm bore smears the roller ends against the rib.", "The 17.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32012X or the ring will bottom out on the radius instead of the shoulder face.", "Grease packs must leave free volume in the 23 mm-wide set; over-greasing a paired bearing churning at the 4,900 r/min oil-band speed raises temperature and destroys the preload setting.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 60 mm shoulder geometry, because retrofitting flips the cups.", "The 91/123 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32012X (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32012X?", "a": "32012X is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 95 mm outside diameter and 23 mm assembled width T (2.362 × 3.74 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 91 kN, C0 123 kN (2203E prints no Pu for this size), grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 596 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32012X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32012X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32012X designation encode the 60 mm bore and what is 4CC?", "a": "last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 95 mm OD and 23 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32012X list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32012X at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32012X mean?", "a": "Suffix reading on 32012X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32012X-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32012x", "4cc", "4t-32012x", "32012X" ], "locale_variants": {} }, { "sku": "33012-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33012", "series": "33000-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 95, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 104, "static_load_kN": 145, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 693, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 33012 denotes the slim 33000 family of metric tapered roller bearings, 60 mm bore, 95 mm outside diameter and 27 mm assembled width T (2.362 × 3.74 × 1.063 in) to the ISO 355 boundary plan. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 33012 resolves to 60 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. With no letter after the number, 33012 is the basic open 4T execution: steel cage, normal adjustment, no seal or special internal-design suffix in the order code. The two speed columns differ by a factor of .76 (grease/limiting 3,700 vs oil 4,900 r/min); heat generation at the cone rib decides which lubrication a real 33012 arrangement can sustain. Open 4T bearings need application seals; without them the grease at the cone rib of 33012 washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 693 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 27 mm section of 33012 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 60 mm bore smears the roller ends against the rib.", "Do not confuse T (27 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Grease packs must leave free volume in the 27 mm-wide set; over-greasing a paired bearing churning at the 4,900 r/min oil-band speed raises temperature and destroys the preload setting.", "ISO 355 makes the 60×95 mm envelope interchangeable but not the ratings: NTN prints 104/145 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 104/145 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33012 (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33012?", "a": "33012 is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 95 mm outside diameter and 27 mm assembled width T (2.362 × 3.74 × 1.063 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 104 kN, C0 145 kN (2203E prints no Pu for this size), grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 693 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33012?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33012); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33012 designation encode the 60 mm bore and what is 2CE?", "a": "last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 95 mm OD and 27 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33012 list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33012 at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33012 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33012", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "4t-33012", "33012", "33012-NTN" ], "locale_variants": {} }, { "sku": "33112-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33112", "series": "33100-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 100, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 126, "static_load_kN": 164, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4700, "weight_g": 913, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33112 is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 60×100 mm ISO 355 envelope, with 30 mm overall assembled width T. Digit by digit, the bare number identifies the light-wide 33100 family and a bore code resolving to 60 mm; 100 mm OD and 30 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. At 126 kN C the bearing offers about 2.1 kN of dynamic capacity per millimetre of the 60 mm bore — compare any substitution on this ratio and the 30 mm assembled T, not on bore alone. Selection: C 126 kN against C0 164 kN gives a C0/C ratio of 1.30 for the 60 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Mount the 60 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 33112.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 913 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The light-wide 33100 family at 60 mm bore (100×30 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,700 r/min oil ceiling.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 60 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 60 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Open 33112 units have no seals: a wheel-hub or gearbox application needs external sealing or the 3,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 126/164 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33112 (ISO 355 3CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33112?", "a": "33112 is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 100 mm outside diameter and 30 mm assembled width T (2.362 × 3.937 × 1.181 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 126 kN, C0 164 kN (2203E prints no Pu for this size), grease limiting speed 3,600 r/min, oil speed 4,700 r/min, mass about 913 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33112?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33112); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33112 designation encode the 60 mm bore and what is 3CE?", "a": "last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 100 mm OD and 30 mm assembled T follow the ISO 355 dimension-series plan. 3CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33112 list two speeds, 3,600 and 4,700 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33112 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33112 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33112", "equiv_brand": "SKF", "level": "partial", "note": "Same 60×100×30 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3ce", "4t-33112", "33112", "33112-NTN" ], "locale_variants": {} }, { "sku": "30212-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30212", "series": "30200-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 110, "B_mm": 23.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 116, "static_load_kN": 125, "limiting_speed_rpm": 3400, "max_rpm": 3400, "speed_oil_rpm": 4500, "weight_g": 929, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 60 mm bore tapered roller position as 30212: one cone assembly, one cup, line-contact rollers and a steel cage, rated 116 kN basic dynamic and 125 kN static on the standard-section 30200 family. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3EB, which is the maker-neutral cross-reference for the 60×110 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN grades 4T metric bearings as open bearings without integral seals; at 60 mm bore the application supplies the seals and the grease fill or oil supply to the 3EB ISO 355 assembly. The 1.9 kN-per-mm-bore capacity figure for 30212 summarises the 116 kN rating over 60 mm bore; use it to sanity-check an interchange candidate before swapping brands. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 30212; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 929 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The standard-section 30200 family at 60 mm bore (110×23.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,500 r/min oil ceiling.", "ISO 355 makes the 60×110 mm envelope interchangeable but not the ratings: NTN prints 116/125 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Replacing one half of an adjusted pair without resetting end play negates the 23.75 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 25.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30212 or the ring will bottom out on the radius instead of the shoulder face.", "The 116/125 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30212 (ISO 355 3EB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30212?", "a": "30212 is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 110 mm outside diameter and 23.75 mm assembled width T (2.362 × 4.331 × 0.935 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 116 kN, C0 125 kN (2203E prints no Pu for this size), grease limiting speed 3,400 r/min, oil speed 4,500 r/min, mass about 929 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30212?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30212); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30212 designation encode the 60 mm bore and what is 3EB?", "a": "last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 23.75 mm assembled T follow the ISO 355 dimension-series plan. 3EB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30212 list two speeds, 3,400 and 4,500 r/min?", "a": "The lower figure, 3,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30212 at 4,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30212 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30212", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "30212-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3eb", "4t-30212", "30212", "30212-NTN" ], "locale_variants": {} }, { "sku": "32212U", "brand": "NTN", "manufacturer_designation": "NTN 32212U", "series": "32200-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 110, "B_mm": 29.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 144, "static_load_kN": 164, "fatigue_load_limit_kN": 20.1, "limiting_speed_rpm": 3400, "max_rpm": 3400, "speed_oil_rpm": 4500, "weight_g": 1180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 60 mm shaft with a thrust component, NTN lists 32212U, a metric 4T tapered roller bearing of 144 kN C and 164 kN C0 inside the 110 mm OD, 29.75 mm-wide assembled set. Digit by digit, the bare number identifies the heavy-section 32200 family and a bore code resolving to 60 mm; 110 mm OD and 29.75 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN grades 4T metric bearings as open bearings without integral seals; at 60 mm bore the application supplies the seals and the grease fill or oil supply to the 3EC ISO 355 assembly. Catalogue mass of the 32212U set is 1180 g (0.046 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32212U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1180 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The heavy-section 32200 family at 60 mm bore (110×29.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,500 r/min oil ceiling.", "Open 32212U units have no seals: a wheel-hub or gearbox application needs external sealing or the 3,400 r/min grease figure is meaningless once water reaches the cone rib.", "Never fit the 60 mm cone by hammering the 110 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 25.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32212U or the ring will bottom out on the radius instead of the shoulder face.", "The 144/164 kN ratings and 20.1 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32212U (ISO 355 3EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32212U?", "a": "32212U is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 110 mm outside diameter and 29.75 mm assembled width T (2.362 × 4.331 × 1.171 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 144 kN, C0 164 kN, Pu 20.1 kN, grease limiting speed 3,400 r/min, oil speed 4,500 r/min, mass about 1180 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32212U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32212U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32212U designation encode the 60 mm bore and what is 3EC?", "a": "last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 29.75 mm assembled T follow the ISO 355 dimension-series plan. 3EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32212U list two speeds, 3,400 and 4,500 r/min?", "a": "The lower figure, 3,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32212U at 4,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32212U mean?", "a": "Suffix reading on 32212U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32212U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32212u", "3ec", "32212U" ], "locale_variants": {} }, { "sku": "33212U", "brand": "NTN", "manufacturer_designation": "NTN 33212U", "series": "33200-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 110, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 179, "static_load_kN": 223, "fatigue_load_limit_kN": 27.1, "limiting_speed_rpm": 3400, "max_rpm": 3400, "speed_oil_rpm": 4500, "weight_g": 1530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 33212U in the medium-wide 33200 family: 60 mm bore, 110 mm cup OD, 38 mm T, with a grease limiting speed of 3,400 r/min and an oil-lubricated ceiling of 4,500 r/min. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 33212U by the metric ISO 355 number (ISO series abbreviation 3EE): 60 mm bore, 110 mm OD. The 25.0 mm radial section carries the roller complement across the 60–110 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The fatigue load limit Pu printed for 33212U is 27.1 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. When pairing 33212U with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1530 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The medium-wide 33200 family at 60 mm bore (110×38 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,500 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 33212U at a large fraction of 3,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Grease packs must leave free volume in the 38 mm-wide set; over-greasing a paired bearing churning at the 4,500 r/min oil-band speed raises temperature and destroys the preload setting.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33212U by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 179/223 kN ratings and 27.1 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33212U (ISO 355 3EE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33212U?", "a": "33212U is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 110 mm outside diameter and 38 mm assembled width T (2.362 × 4.331 × 1.496 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 179 kN, C0 223 kN, Pu 27.1 kN, grease limiting speed 3,400 r/min, oil speed 4,500 r/min, mass about 1530 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33212U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33212U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33212U designation encode the 60 mm bore and what is 3EE?", "a": "last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 38 mm assembled T follow the ISO 355 dimension-series plan. 3EE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33212U list two speeds, 3,400 and 4,500 r/min?", "a": "The lower figure, 3,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33212U at 4,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33212U mean?", "a": "Suffix reading on 33212U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33212U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33212u", "3ee", "33212U" ], "locale_variants": {} }, { "sku": "T2EE060", "brand": "NTN", "manufacturer_designation": "NTN T2EE060", "series": "T2EE-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 115, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 209, "static_load_kN": 249, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 1860, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number T2EE060 denotes the large-size ISO 355 tapered-roller family of metric tapered roller bearings, 60 mm bore, 115 mm outside diameter and 40 mm assembled width T (2.362 × 4.528 × 1.575 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2EE, which is the maker-neutral cross-reference for the 60×115 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts T2EE060 cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Speed planning uses both catalogue columns: grease 3,200 r/min is the cage/rib mechanical ceiling for T2EE060, oil 4,300 r/min is available with circulating oil — a 1,100 r/min margin at this size. Mount the 60 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of T2EE060.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1860 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The large-size ISO 355 tapered-roller family at 60 mm bore (115×40 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,300 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded T2EE060 at a large fraction of 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 27.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for T2EE060 or the ring will bottom out on the radius instead of the shoulder face.", "Do not confuse T (40 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 209/249 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T2EE060 (ISO 355 2EE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T2EE060?", "a": "T2EE060 is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 115 mm outside diameter and 40 mm assembled width T (2.362 × 4.528 × 1.575 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 209 kN, C0 249 kN (2203E prints no Pu for this size), grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 1860 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T2EE060?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T2EE060); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T2EE060 designation encode the 60 mm bore and what is 2EE?", "a": "trailing dimension block 060 prints the 60 mm bore directly for this large-size T-code. The 115 mm OD and 40 mm assembled T follow the ISO 355 dimension-series plan. 2EE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T2EE060 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T2EE060 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T2EE060 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 60 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T2EE060", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ee", "4t-t2ee060", "t2ee060", "T2EE060" ], "locale_variants": {} }, { "sku": "T7FC060", "brand": "NTN", "manufacturer_designation": "NTN T7FC060", "series": "T7FC-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 125, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 161, "static_load_kN": 186, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3700, "weight_g": 2000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 60 mm bore tapered roller position as T7FC060: one cone assembly, one cup, line-contact rollers and a steel cage, rated 161 kN basic dynamic and 186 kN static on the large-size ISO 355 tapered-roller family. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 7FC, which is the maker-neutral cross-reference for the 60×125 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 60 mm bore directly, and remains an open 4T execution ordered under its own code. Selection: C 161 kN against C0 186 kN gives a C0/C ratio of 1.16 for the 60 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 60 mm pair is misadjusted and the 37 mm T set will edge-load in service.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2000 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The large-size ISO 355 tapered-roller family at 60 mm bore (125×37 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,700 r/min oil ceiling.", "ISO 355 makes the 60×125 mm envelope interchangeable but not the ratings: NTN prints 161/186 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering T7FC060 by size alone can deliver the wrong contact-angle execution for a pinion position.", "ISO 355 makes the 60×125 mm envelope interchangeable but not the ratings: NTN prints 161/186 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 161/186 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T7FC060 (ISO 355 7FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T7FC060?", "a": "T7FC060 is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 125 mm outside diameter and 37 mm assembled width T (2.362 × 4.921 × 1.457 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 161 kN, C0 186 kN (2203E prints no Pu for this size), grease limiting speed 2,800 r/min, oil speed 3,700 r/min, mass about 2000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T7FC060?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T7FC060); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T7FC060 designation encode the 60 mm bore and what is 7FC?", "a": "trailing dimension block 060 prints the 60 mm bore directly for this large-size T-code. The 125 mm OD and 37 mm assembled T follow the ISO 355 dimension-series plan. 7FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T7FC060 list two speeds, 2,800 and 3,700 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T7FC060 at 3,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T7FC060 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 60 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T7FC060", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-t7fc060", "7fc", "t7fc060", "T7FC060" ], "locale_variants": {} }, { "sku": "30312D", "brand": "NTN", "manufacturer_designation": "NTN 30312D", "series": "30300-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 130, "B_mm": 33.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 167, "static_load_kN": 176, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30312D is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 60×130 mm ISO 355 envelope, with 33.5 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30312D by the metric ISO 355 number (ISO series abbreviation 7FB): 60 mm bore, 130 mm OD. NTN grades 4T metric bearings as open bearings without integral seals; at 60 mm bore the application supplies the seals and the grease fill or oil supply to the 7FB ISO 355 assembly. The 2.8 kN-per-mm-bore capacity figure for 30312D summarises the 167 kN rating over 60 mm bore; use it to sanity-check an interchange candidate before swapping brands. When pairing 30312D with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1950 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 60 mm bore; do not swap to the lighter family without re-checking the 2,700 r/min grease limit and the thrust load split.", "ISO 355 makes the 60×130 mm envelope interchangeable but not the ratings: NTN prints 167/176 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Grease packs must leave free volume in the 33.5 mm-wide set; over-greasing a paired bearing churning at the 3,600 r/min oil-band speed raises temperature and destroys the preload setting.", "The 35.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30312D or the ring will bottom out on the radius instead of the shoulder face.", "The 167/176 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30312D (ISO 355 7FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30312D?", "a": "30312D is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 130 mm outside diameter and 33.5 mm assembled width T (2.362 × 5.118 × 1.319 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 167 kN, C0 176 kN (2203E prints no Pu for this size), grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 1950 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30312D?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30312D); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30312D designation encode the 60 mm bore and what is 7FB?", "a": "last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 33.5 mm assembled T follow the ISO 355 dimension-series plan. 7FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30312D list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30312D at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30312D mean?", "a": "Suffix reading on 30312D: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30312D", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30312d", "4t-30312d", "7fb", "30312D" ], "locale_variants": {} }, { "sku": "30312U", "brand": "NTN", "manufacturer_designation": "NTN 30312U", "series": "30300-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 130, "B_mm": 33.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 199, "static_load_kN": 210, "fatigue_load_limit_kN": 25.6, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 2050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30312U is the NTN 4T catalogue entry for a 60×130×33.5 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2FB, which is the maker-neutral cross-reference for the 60×130 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 30312U cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The two speed columns differ by a factor of .75 (grease/limiting 3,000 vs oil 4,000 r/min); heat generation at the cone rib decides which lubrication a real 30312U arrangement can sustain. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 60 mm pair is misadjusted and the 33.5 mm T set will edge-load in service.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2050 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 60 mm bore; do not swap to the lighter family without re-checking the 3,000 r/min grease limit and the thrust load split.", "Do not confuse T (33.5 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "ISO 355 makes the 60×130 mm envelope interchangeable but not the ratings: NTN prints 199/210 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Do not confuse T (33.5 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 199/210 kN ratings and 25.6 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30312U (ISO 355 2FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30312U?", "a": "30312U is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 130 mm outside diameter and 33.5 mm assembled width T (2.362 × 5.118 × 1.319 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 199 kN, C0 210 kN, Pu 25.6 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 2050 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30312U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30312U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30312U designation encode the 60 mm bore and what is 2FB?", "a": "last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 33.5 mm assembled T follow the ISO 355 dimension-series plan. 2FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30312U list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30312U at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30312U mean?", "a": "Suffix reading on 30312U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30312U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fb", "30312u", "30312U" ], "locale_variants": {} }, { "sku": "32312C", "brand": "NTN", "manufacturer_designation": "NTN 32312C", "series": "32300-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 130, "B_mm": 48.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 237, "static_load_kN": 296, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3900, "weight_g": 3070, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32312C belongs to the NTN metric 4T tapered roller range (extra-heavy 32300 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Digit by digit, the bare number identifies the extra-heavy 32300 family and a bore code resolving to 60 mm; 130 mm OD and 48.5 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The 35.0 mm radial section carries the roller complement across the 60–130 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The 4.0 kN-per-mm-bore capacity figure for 32312C summarises the 237 kN rating over 60 mm bore; use it to sanity-check an interchange candidate before swapping brands. Mount the 60 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32312C.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3070 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 60 mm bore (130×48.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,900 r/min oil ceiling.", "Never fit the 60 mm cone by hammering the 130 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Replacing one half of an adjusted pair without resetting end play negates the 48.5 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32312C by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 237/296 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32312C (ISO 355 5FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32312C?", "a": "32312C is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 130 mm outside diameter and 48.5 mm assembled width T (2.362 × 5.118 × 1.909 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 237 kN, C0 296 kN (2203E prints no Pu for this size), grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 3070 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32312C?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32312C); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32312C designation encode the 60 mm bore and what is 5FD?", "a": "last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 48.5 mm assembled T follow the ISO 355 dimension-series plan. 5FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32312C list two speeds, 2,900 and 3,900 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32312C at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32312C mean?", "a": "Suffix reading on 32312C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32312C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32312c", "4t-32312c", "5fd", "32312C" ], "locale_variants": {} }, { "sku": "32312U", "brand": "NTN", "manufacturer_designation": "NTN 32312U", "series": "32300-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 130, "B_mm": 48.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 271, "static_load_kN": 315, "fatigue_load_limit_kN": 38.5, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 3010, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32312U is the NTN 4T catalogue entry for a 60×130×48.5 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. The last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 48.5 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Suffix reading on 32312U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. The 4.5 kN-per-mm-bore capacity figure for 32312U summarises the 271 kN rating over 60 mm bore; use it to sanity-check an interchange candidate before swapping brands. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32312U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3010 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 60 mm bore (130×48.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,000 r/min oil ceiling.", "ISO 355 makes the 60×130 mm envelope interchangeable but not the ratings: NTN prints 271/315 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Grease packs must leave free volume in the 48.5 mm-wide set; over-greasing a paired bearing churning at the 4,000 r/min oil-band speed raises temperature and destroys the preload setting.", "ISO 355 makes the 60×130 mm envelope interchangeable but not the ratings: NTN prints 271/315 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 271/315 kN ratings and 38.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32312U (ISO 355 2FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32312U?", "a": "32312U is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 130 mm outside diameter and 48.5 mm assembled width T (2.362 × 5.118 × 1.909 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 271 kN, C0 315 kN, Pu 38.5 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 3010 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32312U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32312U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32312U designation encode the 60 mm bore and what is 2FD?", "a": "last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 48.5 mm assembled T follow the ISO 355 dimension-series plan. 2FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32312U list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32312U at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32312U mean?", "a": "Suffix reading on 32312U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32312U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fd", "32312u", "32312U" ], "locale_variants": {} }, { "sku": "32913XU", "brand": "NTN", "manufacturer_designation": "NTN 32913XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 90, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53.5, "static_load_kN": 85, "fatigue_load_limit_kN": 10.4, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 315, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32913XU is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 65×90 mm ISO 355 envelope, with 17 mm overall assembled width T. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 65 mm; 90 mm OD and 17 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. Individually mounted, 32913XU takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The 12.5 mm section height over the 65 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Open 4T bearings need application seals; without them the grease at the cone rib of 32913XU washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 315 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 17 mm section of 32913XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 65 mm bore smears the roller ends against the rib.", "ISO 355 makes the 65×90 mm envelope interchangeable but not the ratings: NTN prints 53.5/85 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Never fit the 65 mm cone by hammering the 90 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never fit the 65 mm cone by hammering the 90 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 53.5/85 kN ratings and 10.4 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32913XU (ISO 355 2BC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32913XU?", "a": "32913XU is a metric 4T tapered roller bearing to ISO 355: 65 mm bore, 90 mm outside diameter and 17 mm assembled width T (2.559 × 3.543 × 0.669 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53.5 kN, C0 85 kN, Pu 10.4 kN, grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 315 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32913XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32913XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32913XU designation encode the 65 mm bore and what is 2BC?", "a": "last two digits 13 are the ISO bore code, ×5 = 65 mm (codes 00–03 use the 10/12/15/17 exception table). The 90 mm OD and 17 mm assembled T follow the ISO 355 dimension-series plan. 2BC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32913XU list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32913XU at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32913XU mean?", "a": "Suffix reading on 32913XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32913XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bc", "32913xu", "32913XU" ], "locale_variants": {} }, { "sku": "32013X", "brand": "NTN", "manufacturer_designation": "NTN 32013X", "series": "32000-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 100, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 92, "static_load_kN": 128, "limiting_speed_rpm": 3400, "max_rpm": 3400, "speed_oil_rpm": 4600, "weight_g": 631, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32013X denotes the low-section 32000 family tuned for low friction of metric tapered roller bearings, 65 mm bore, 100 mm outside diameter and 23 mm assembled width T (2.559 × 3.937 × 0.906 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4CC, which is the maker-neutral cross-reference for the 65×100 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. 2203E lists two speed ceilings for 32013X: 3,400 r/min with grease lubrication (the limiting speed) and 4,600 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. 2203E does not print a Pu fatigue load limit for 32013X; life work for this size uses the 92/128 kN C/C0 pair directly. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 65 mm pair is misadjusted and the 23 mm T set will edge-load in service.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 631 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 23 mm section of 32013X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 65 mm bore smears the roller ends against the rib.", "ISO 355 makes the 65×100 mm envelope interchangeable but not the ratings: NTN prints 92/128 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Minimum load matters at high speed: an unloaded 32013X at a large fraction of 3,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Grease packs must leave free volume in the 23 mm-wide set; over-greasing a paired bearing churning at the 4,600 r/min oil-band speed raises temperature and destroys the preload setting.", "The 92/128 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32013X (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32013X?", "a": "32013X is a metric 4T tapered roller bearing to ISO 355: 65 mm bore, 100 mm outside diameter and 23 mm assembled width T (2.559 × 3.937 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 92 kN, C0 128 kN (2203E prints no Pu for this size), grease limiting speed 3,400 r/min, oil speed 4,600 r/min, mass about 631 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32013X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32013X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32013X designation encode the 65 mm bore and what is 4CC?", "a": "last two digits 13 are the ISO bore code, ×5 = 65 mm (codes 00–03 use the 10/12/15/17 exception table). The 100 mm OD and 23 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32013X list two speeds, 3,400 and 4,600 r/min?", "a": "The lower figure, 3,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32013X at 4,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32013X mean?", "a": "Suffix reading on 32013X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32013X-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32013x", "4cc", "4t-32013x", "32013X" ], "locale_variants": {} }, { "sku": "33013-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33013", "series": "33000-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 100, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 108, "static_load_kN": 156, "limiting_speed_rpm": 3400, "max_rpm": 3400, "speed_oil_rpm": 4600, "weight_g": 742, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33013 is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 65×100 mm ISO 355 envelope, with 27 mm overall assembled width T. The last two digits 13 are the ISO bore code, ×5 = 65 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 27 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. NTN grades 4T metric bearings as open bearings without integral seals; at 65 mm bore the application supplies the seals and the grease fill or oil supply to the 2CE ISO 355 assembly. Imperial cross-check for the drawing: 65×100×27 mm is 2.559 × 3.937 × 1.063 in; ISO 355 makes the envelope interchangeable but C/C0, 108/156 kN, is NTN-specific. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 33013; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 742 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 27 mm section of 33013 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 65 mm bore smears the roller ends against the rib.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33013 by size alone can deliver the wrong contact-angle execution for a pinion position.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 65 mm shoulder geometry, because retrofitting flips the cups.", "The 17.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33013 or the ring will bottom out on the radius instead of the shoulder face.", "The 108/156 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33013 (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33013?", "a": "33013 is a metric 4T tapered roller bearing to ISO 355: 65 mm bore, 100 mm outside diameter and 27 mm assembled width T (2.559 × 3.937 × 1.063 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 108 kN, C0 156 kN (2203E prints no Pu for this size), grease limiting speed 3,400 r/min, oil speed 4,600 r/min, mass about 742 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33013?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33013); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33013 designation encode the 65 mm bore and what is 2CE?", "a": "last two digits 13 are the ISO bore code, ×5 = 65 mm (codes 00–03 use the 10/12/15/17 exception table). The 100 mm OD and 27 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33013 list two speeds, 3,400 and 4,600 r/min?", "a": "The lower figure, 3,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33013 at 4,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33013 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33013", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "33013-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "4t-33013", "33013", "33013-NTN" ], "locale_variants": {} }, { "sku": "33113-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33113", "series": "33100-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 110, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 160, "static_load_kN": 211, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4400, "weight_g": 1270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 33113 denotes the light-wide 33100 family of metric tapered roller bearings, 65 mm bore, 110 mm outside diameter and 34 mm assembled width T (2.559 × 4.331 × 1.339 in) to the ISO 355 boundary plan. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 33113 by the metric ISO 355 number (ISO series abbreviation 3DE): 65 mm bore, 110 mm OD. The 22.5 mm radial section carries the roller complement across the 65–110 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The two speed columns differ by a factor of .75 (grease/limiting 3,300 vs oil 4,400 r/min); heat generation at the cone rib decides which lubrication a real 33113 arrangement can sustain. Mount the 65 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 33113.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1270 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The light-wide 33100 family at 65 mm bore (110×34 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,400 r/min oil ceiling.", "Do not confuse T (34 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Minimum load matters at high speed: an unloaded 33113 at a large fraction of 3,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33113 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 160/211 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33113 (ISO 355 3DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33113?", "a": "33113 is a metric 4T tapered roller bearing to ISO 355: 65 mm bore, 110 mm outside diameter and 34 mm assembled width T (2.559 × 4.331 × 1.339 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 160 kN, C0 211 kN (2203E prints no Pu for this size), grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 1270 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33113?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33113); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33113 designation encode the 65 mm bore and what is 3DE?", "a": "last two digits 13 are the ISO bore code, ×5 = 65 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 34 mm assembled T follow the ISO 355 dimension-series plan. 3DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33113 list two speeds, 3,300 and 4,400 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33113 at 4,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33113 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33113", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3de", "4t-33113", "33113", "33113-NTN" ], "locale_variants": {} }, { "sku": "30213-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30213", "series": "30200-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 120, "B_mm": 24.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 136, "static_load_kN": 148, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4200, "weight_g": 1180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30213 is the NTN 4T catalogue entry for a 65×120×24.75 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30213 resolves to 65 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. At 136 kN C the bearing offers about 2.1 kN of dynamic capacity per millimetre of the 65 mm bore — compare any substitution on this ratio and the 24.75 mm assembled T, not on bore alone. Grease relubrication at 3,100 r/min limiting speed targets the rib contact; if the drive needs 4,200 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 30213; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1180 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The standard-section 30200 family at 65 mm bore (120×24.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,200 r/min oil ceiling.", "Grease packs must leave free volume in the 24.75 mm-wide set; over-greasing a paired bearing churning at the 4,200 r/min oil-band speed raises temperature and destroys the preload setting.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30213 by size alone can deliver the wrong contact-angle execution for a pinion position.", "Open 30213 units have no seals: a wheel-hub or gearbox application needs external sealing or the 3,100 r/min grease figure is meaningless once water reaches the cone rib.", "The 136/148 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30213 (ISO 355 3EB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30213?", "a": "30213 is a metric 4T tapered roller bearing to ISO 355: 65 mm bore, 120 mm outside diameter and 24.75 mm assembled width T (2.559 × 4.724 × 0.974 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 136 kN, C0 148 kN (2203E prints no Pu for this size), grease limiting speed 3,100 r/min, oil speed 4,200 r/min, mass about 1180 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30213?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30213); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30213 designation encode the 65 mm bore and what is 3EB?", "a": "last two digits 13 are the ISO bore code, ×5 = 65 mm (codes 00–03 use the 10/12/15/17 exception table). The 120 mm OD and 24.75 mm assembled T follow the ISO 355 dimension-series plan. 3EB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30213 list two speeds, 3,100 and 4,200 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30213 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30213 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30213", "equiv_brand": "SKF", "level": "partial", "note": "Same 65×120×24.75 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "30213-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3eb", "4t-30213", "30213", "30213-NTN" ], "locale_variants": {} }, { "sku": "32213U", "brand": "NTN", "manufacturer_designation": "NTN 32213U", "series": "32200-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 120, "B_mm": 32.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 176, "static_load_kN": 206, "fatigue_load_limit_kN": 25.1, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4200, "weight_g": 1570, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32213U denotes the heavy-section 32200 family of metric tapered roller bearings, 65 mm bore, 120 mm outside diameter and 32.75 mm assembled width T (2.559 × 4.724 × 1.289 in) to the ISO 355 boundary plan. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32213U by the metric ISO 355 number (ISO series abbreviation 3EC): 65 mm bore, 120 mm OD. The 27.5 mm radial section carries the roller complement across the 65–120 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The 27.5 mm section height over the 65 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 32213U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1570 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The heavy-section 32200 family at 65 mm bore (120×32.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,200 r/min oil ceiling.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 65 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 65 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32213U by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 176/206 kN ratings and 25.1 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32213U (ISO 355 3EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32213U?", "a": "32213U is a metric 4T tapered roller bearing to ISO 355: 65 mm bore, 120 mm outside diameter and 32.75 mm assembled width T (2.559 × 4.724 × 1.289 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 176 kN, C0 206 kN, Pu 25.1 kN, grease limiting speed 3,100 r/min, oil speed 4,200 r/min, mass about 1570 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32213U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32213U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32213U designation encode the 65 mm bore and what is 3EC?", "a": "last two digits 13 are the ISO bore code, ×5 = 65 mm (codes 00–03 use the 10/12/15/17 exception table). The 120 mm OD and 32.75 mm assembled T follow the ISO 355 dimension-series plan. 3EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32213U list two speeds, 3,100 and 4,200 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32213U at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32213U mean?", "a": "Suffix reading on 32213U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32213U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32213u", "3ec", "32213U" ], "locale_variants": {} }, { "sku": "33213U", "brand": "NTN", "manufacturer_designation": "NTN 33213U", "series": "33200-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 120, "B_mm": 41, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 216, "static_load_kN": 265, "fatigue_load_limit_kN": 32.5, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4200, "weight_g": 2000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33213U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 65×120 mm ISO 355 envelope, with 41 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3EE, which is the maker-neutral cross-reference for the 65×120 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Catalogue mass of the 33213U set is 2000 g (0.079 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Fillet radii must clear the ring chamfers of the 120 mm cup and 65 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2000 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The medium-wide 33200 family at 65 mm bore (120×41 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,200 r/min oil ceiling.", "Do not confuse T (41 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Minimum load matters at high speed: an unloaded 33213U at a large fraction of 3,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Replacing one half of an adjusted pair without resetting end play negates the 41 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 216/265 kN ratings and 32.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33213U (ISO 355 3EE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33213U?", "a": "33213U is a metric 4T tapered roller bearing to ISO 355: 65 mm bore, 120 mm outside diameter and 41 mm assembled width T (2.559 × 4.724 × 1.614 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 216 kN, C0 265 kN, Pu 32.5 kN, grease limiting speed 3,100 r/min, oil speed 4,200 r/min, mass about 2000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33213U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33213U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33213U designation encode the 65 mm bore and what is 3EE?", "a": "last two digits 13 are the ISO bore code, ×5 = 65 mm (codes 00–03 use the 10/12/15/17 exception table). The 120 mm OD and 41 mm assembled T follow the ISO 355 dimension-series plan. 3EE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33213U list two speeds, 3,100 and 4,200 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33213U at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33213U mean?", "a": "Suffix reading on 33213U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33213U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33213u", "3ee", "33213U" ], "locale_variants": {} }, { "sku": "30313D", "brand": "NTN", "manufacturer_designation": "NTN 30313D", "series": "30300-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 140, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 192, "static_load_kN": 204, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 2410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30313D is the NTN 4T catalogue entry for a 65×140×36 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 7GB, which is the maker-neutral cross-reference for the 65×140 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The 37.5 mm radial section carries the roller complement across the 65–140 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Imperial cross-check for the drawing: 65×140×36 mm is 2.559 × 5.512 × 1.417 in; ISO 355 makes the envelope interchangeable but C/C0, 192/204 kN, is NTN-specific. Fillet radii must clear the ring chamfers of the 140 mm cup and 65 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2410 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 65 mm bore; do not swap to the lighter family without re-checking the 2,500 r/min grease limit and the thrust load split.", "Never fit the 65 mm cone by hammering the 140 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Minimum load matters at high speed: an unloaded 30313D at a large fraction of 2,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30313D by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 192/204 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30313D (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30313D?", "a": "30313D is a metric 4T tapered roller bearing to ISO 355: 65 mm bore, 140 mm outside diameter and 36 mm assembled width T (2.559 × 5.512 × 1.417 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 192 kN, C0 204 kN (2203E prints no Pu for this size), grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 2410 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30313D?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30313D); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30313D designation encode the 65 mm bore and what is 7GB?", "a": "last two digits 13 are the ISO bore code, ×5 = 65 mm (codes 00–03 use the 10/12/15/17 exception table). The 140 mm OD and 36 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30313D list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30313D at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30313D mean?", "a": "Suffix reading on 30313D: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30313D", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30313d", "4t-30313d", "7gb", "30313D" ], "locale_variants": {} }, { "sku": "30313U", "brand": "NTN", "manufacturer_designation": "NTN 30313U", "series": "30300-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 140, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 225, "static_load_kN": 238, "fatigue_load_limit_kN": 28.7, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3700, "weight_g": 2540, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30313U belongs to the NTN metric 4T tapered roller range (large-OD 30300 family with the steeper contact angle); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30313U resolves to 65 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The printed contact-angle geometry gives the large-OD 30300 family with the steeper contact angle its characteristic load split — at 225/238 kN (C/C0) the static rating is about 1.06× C, typical of tapered bearings proportioned for heavy combined duty. Selection: C 225 kN against C0 238 kN gives a C0/C ratio of 1.06 for the 65 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 30313U washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2540 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 65 mm bore; do not swap to the lighter family without re-checking the 2,800 r/min grease limit and the thrust load split.", "Replacing one half of an adjusted pair without resetting end play negates the 36 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 30313U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,800 r/min grease figure is meaningless once water reaches the cone rib.", "Minimum load matters at high speed: an unloaded 30313U at a large fraction of 2,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 225/238 kN ratings and 28.7 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30313U (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30313U?", "a": "30313U is a metric 4T tapered roller bearing to ISO 355: 65 mm bore, 140 mm outside diameter and 36 mm assembled width T (2.559 × 5.512 × 1.417 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 225 kN, C0 238 kN, Pu 28.7 kN, grease limiting speed 2,800 r/min, oil speed 3,700 r/min, mass about 2540 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30313U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30313U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30313U designation encode the 65 mm bore and what is 2GB?", "a": "last two digits 13 are the ISO bore code, ×5 = 65 mm (codes 00–03 use the 10/12/15/17 exception table). The 140 mm OD and 36 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30313U list two speeds, 2,800 and 3,700 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30313U at 3,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30313U mean?", "a": "Suffix reading on 30313U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30313U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30313u", "30313U" ], "locale_variants": {} }, { "sku": "32313U", "brand": "NTN", "manufacturer_designation": "NTN 32313U", "series": "32300-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 140, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 305, "static_load_kN": 350, "fatigue_load_limit_kN": 42.5, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3700, "weight_g": 3630, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32313U belongs to the NTN metric 4T tapered roller range (extra-heavy 32300 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Digit by digit, the bare number identifies the extra-heavy 32300 family and a bore code resolving to 65 mm; 140 mm OD and 51 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN grades 4T metric bearings as open bearings without integral seals; at 65 mm bore the application supplies the seals and the grease fill or oil supply to the 2GD ISO 355 assembly. Imperial cross-check for the drawing: 65×140×51 mm is 2.559 × 5.512 × 2.008 in; ISO 355 makes the envelope interchangeable but C/C0, 305/350 kN, is NTN-specific. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 32313U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3630 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 65 mm bore (140×51 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,700 r/min oil ceiling.", "Never fit the 65 mm cone by hammering the 140 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Minimum load matters at high speed: an unloaded 32313U at a large fraction of 2,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 37.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32313U or the ring will bottom out on the radius instead of the shoulder face.", "The 305/350 kN ratings and 42.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32313U (ISO 355 2GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32313U?", "a": "32313U is a metric 4T tapered roller bearing to ISO 355: 65 mm bore, 140 mm outside diameter and 51 mm assembled width T (2.559 × 5.512 × 2.008 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 305 kN, C0 350 kN, Pu 42.5 kN, grease limiting speed 2,800 r/min, oil speed 3,700 r/min, mass about 3630 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32313U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32313U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32313U designation encode the 65 mm bore and what is 2GD?", "a": "last two digits 13 are the ISO bore code, ×5 = 65 mm (codes 00–03 use the 10/12/15/17 exception table). The 140 mm OD and 51 mm assembled T follow the ISO 355 dimension-series plan. 2GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32313U list two speeds, 2,800 and 3,700 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32313U at 3,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32313U mean?", "a": "Suffix reading on 32313U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32313U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gd", "32313u", "32313U" ], "locale_variants": {} }, { "sku": "32914XU", "brand": "NTN", "manufacturer_designation": "NTN 32914XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 100, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 76, "static_load_kN": 110, "fatigue_load_limit_kN": 13.4, "limiting_speed_rpm": 3400, "max_rpm": 3400, "speed_oil_rpm": 4600, "weight_g": 475, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 70 mm bore tapered roller position as 32914XU: one cone assembly, one cup, line-contact rollers and a steel cage, rated 76 kN basic dynamic and 110 kN static on the extra-light thin-section 32900 family. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2BC, which is the maker-neutral cross-reference for the 70×100 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32914XU, since running clearance is set during assembly. The two speed columns differ by a factor of .74 (grease/limiting 3,400 vs oil 4,600 r/min); heat generation at the cone rib decides which lubrication a real 32914XU arrangement can sustain. Open 4T bearings need application seals; without them the grease at the cone rib of 32914XU washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 475 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 20 mm section of 32914XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 70 mm bore smears the roller ends against the rib.", "Open 32914XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 3,400 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 20 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 70 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 76/110 kN ratings and 13.4 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32914XU (ISO 355 2BC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32914XU?", "a": "32914XU is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 100 mm outside diameter and 20 mm assembled width T (2.756 × 3.937 × 0.787 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 76 kN, C0 110 kN, Pu 13.4 kN, grease limiting speed 3,400 r/min, oil speed 4,600 r/min, mass about 475 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32914XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32914XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32914XU designation encode the 70 mm bore and what is 2BC?", "a": "last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 100 mm OD and 20 mm assembled T follow the ISO 355 dimension-series plan. 2BC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32914XU list two speeds, 3,400 and 4,600 r/min?", "a": "The lower figure, 3,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32914XU at 4,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32914XU mean?", "a": "Suffix reading on 32914XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32914XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bc", "32914xu", "32914XU" ], "locale_variants": {} }, { "sku": "32014X", "brand": "NTN", "manufacturer_designation": "NTN 32014X", "series": "32000-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 110, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 116, "static_load_kN": 160, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 863, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32014X in the low-section 32000 family tuned for low friction: 70 mm bore, 110 mm cup OD, 25 mm T, with a grease limiting speed of 3,200 r/min and an oil-lubricated ceiling of 4,200 r/min. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32014X resolves to 70 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Individually mounted, 32014X takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Catalogue mass of the 32014X set is 863 g (0.034 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Open 4T bearings need application seals; without them the grease at the cone rib of 32014X washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 863 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 25 mm section of 32014X is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 70 mm bore smears the roller ends against the rib.", "Never fit the 70 mm cone by hammering the 110 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 20.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32014X or the ring will bottom out on the radius instead of the shoulder face.", "Never fit the 70 mm cone by hammering the 110 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 116/160 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32014X (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32014X?", "a": "32014X is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 110 mm outside diameter and 25 mm assembled width T (2.756 × 4.331 × 0.984 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 116 kN, C0 160 kN (2203E prints no Pu for this size), grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 863 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32014X?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32014X); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32014X designation encode the 70 mm bore and what is 4CC?", "a": "last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 25 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32014X list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32014X at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32014X mean?", "a": "Suffix reading on 32014X: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32014X-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32014x", "4cc", "4t-32014x", "32014X" ], "locale_variants": {} }, { "sku": "33014-NTN", "brand": "NTN", "manufacturer_designation": "NTN 33014", "series": "33000-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 110, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 140, "static_load_kN": 204, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1070, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 33014 denotes the slim 33000 family of metric tapered roller bearings, 70 mm bore, 110 mm outside diameter and 31 mm assembled width T (2.756 × 4.331 × 1.22 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the slim 33000 family and a bore code resolving to 70 mm; 110 mm OD and 31 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. At 140 kN C the bearing offers about 2.0 kN of dynamic capacity per millimetre of the 70 mm bore — compare any substitution on this ratio and the 31 mm assembled T, not on bore alone. The 2.0 kN-per-mm-bore capacity figure for 33014 summarises the 140 kN rating over 70 mm bore; use it to sanity-check an interchange candidate before swapping brands. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 33014; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1070 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 31 mm section of 33014 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 70 mm bore smears the roller ends against the rib.", "ISO 355 makes the 70×110 mm envelope interchangeable but not the ratings: NTN prints 140/204 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Open 33014 units have no seals: a wheel-hub or gearbox application needs external sealing or the 3,200 r/min grease figure is meaningless once water reaches the cone rib.", "Open 33014 units have no seals: a wheel-hub or gearbox application needs external sealing or the 3,200 r/min grease figure is meaningless once water reaches the cone rib.", "The 140/204 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33014 (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33014?", "a": "33014 is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 110 mm outside diameter and 31 mm assembled width T (2.756 × 4.331 × 1.22 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 140 kN, C0 204 kN (2203E prints no Pu for this size), grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1070 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33014?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33014); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33014 designation encode the 70 mm bore and what is 2CE?", "a": "last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 31 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33014 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33014 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33014 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "33014", "equiv_brand": "SKF", "level": "partial", "note": "Same 70×110×31 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "33014-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "4t-33014", "33014", "33014-NTN" ], "locale_variants": {} }, { "sku": "33114U", "brand": "NTN", "manufacturer_designation": "NTN 33114U", "series": "33100-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 120, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 190, "static_load_kN": 251, "fatigue_load_limit_kN": 30.5, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 1680, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 70 mm shaft with a thrust component, NTN lists 33114U, a metric 4T tapered roller bearing of 190 kN C and 251 kN C0 inside the 120 mm OD, 37 mm-wide assembled set. The last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 37 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. The fatigue load limit Pu printed for 33114U is 30.5 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Mount the 70 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 33114U.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1680 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The light-wide 33100 family at 70 mm bore (120×37 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 4,100 r/min oil ceiling.", "Never fit the 70 mm cone by hammering the 120 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume in the 37 mm-wide set; over-greasing a paired bearing churning at the 4,100 r/min oil-band speed raises temperature and destroys the preload setting.", "Replacing one half of an adjusted pair without resetting end play negates the 37 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 190/251 kN ratings and 30.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33114U (ISO 355 3DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33114U?", "a": "33114U is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 120 mm outside diameter and 37 mm assembled width T (2.756 × 4.724 × 1.457 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 190 kN, C0 251 kN, Pu 30.5 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 1680 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33114U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33114U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33114U designation encode the 70 mm bore and what is 3DE?", "a": "last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 120 mm OD and 37 mm assembled T follow the ISO 355 dimension-series plan. 3DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33114U list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33114U at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33114U mean?", "a": "Suffix reading on 33114U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33114U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33114u", "3de", "33114U" ], "locale_variants": {} }, { "sku": "30214-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30214", "series": "30200-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 125, "B_mm": 26.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 146, "static_load_kN": 162, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3900, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30214 in the standard-section 30200 family: 70 mm bore, 125 mm cup OD, 26.25 mm T, with a grease limiting speed of 2,900 r/min and an oil-lubricated ceiling of 3,900 r/min. The last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 26.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The 27.5 mm radial section carries the roller complement across the 70–125 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The 27.5 mm section height over the 70 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 30214; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1300 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The standard-section 30200 family at 70 mm bore (125×26.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,900 r/min oil ceiling.", "Open 30214 units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,900 r/min grease figure is meaningless once water reaches the cone rib.", "The 27.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30214 or the ring will bottom out on the radius instead of the shoulder face.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30214 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 146/162 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30214 (ISO 355 3EB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30214?", "a": "30214 is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 125 mm outside diameter and 26.25 mm assembled width T (2.756 × 4.921 × 1.033 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 146 kN, C0 162 kN (2203E prints no Pu for this size), grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 1300 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30214?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30214); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30214 designation encode the 70 mm bore and what is 3EB?", "a": "last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 125 mm OD and 26.25 mm assembled T follow the ISO 355 dimension-series plan. 3EB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30214 list two speeds, 2,900 and 3,900 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30214 at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30214 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30214", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "3eb", "4t-30214", "30214", "30214-NTN" ], "locale_variants": {} }, { "sku": "32214U", "brand": "NTN", "manufacturer_designation": "NTN 32214U", "series": "32200-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 125, "B_mm": 33.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 184, "static_load_kN": 220, "fatigue_load_limit_kN": 26.8, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3900, "weight_g": 1680, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32214U in the heavy-section 32200 family: 70 mm bore, 125 mm cup OD, 33.25 mm T, with a grease limiting speed of 2,900 r/min and an oil-lubricated ceiling of 3,900 r/min. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3EC, which is the maker-neutral cross-reference for the 70×125 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Grease relubrication at 2,900 r/min limiting speed targets the rib contact; if the drive needs 3,900 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 70 mm pair is misadjusted and the 33.25 mm T set will edge-load in service.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1680 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The heavy-section 32200 family at 70 mm bore (125×33.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,900 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 32214U at a large fraction of 2,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32214U by size alone can deliver the wrong contact-angle execution for a pinion position.", "Replacing one half of an adjusted pair without resetting end play negates the 33.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 184/220 kN ratings and 26.8 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32214U (ISO 355 3EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32214U?", "a": "32214U is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 125 mm outside diameter and 33.25 mm assembled width T (2.756 × 4.921 × 1.309 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 184 kN, C0 220 kN, Pu 26.8 kN, grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 1680 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32214U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32214U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32214U designation encode the 70 mm bore and what is 3EC?", "a": "last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 125 mm OD and 33.25 mm assembled T follow the ISO 355 dimension-series plan. 3EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32214U list two speeds, 2,900 and 3,900 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32214U at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32214U mean?", "a": "Suffix reading on 32214U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32214U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32214u", "3ec", "32214U" ], "locale_variants": {} }, { "sku": "33214U", "brand": "NTN", "manufacturer_designation": "NTN 33214U", "series": "33200-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 125, "B_mm": 41, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 223, "static_load_kN": 282, "fatigue_load_limit_kN": 34.5, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3900, "weight_g": 2120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33214U is the NTN 4T catalogue entry for a 70×125×41 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 33214U resolves to 70 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 33214U cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The 27.5 mm section height over the 70 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 33214U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2120 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The medium-wide 33200 family at 70 mm bore (125×41 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,900 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 41 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 27.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33214U or the ring will bottom out on the radius instead of the shoulder face.", "Do not confuse T (41 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 223/282 kN ratings and 34.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33214U (ISO 355 3EE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33214U?", "a": "33214U is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 125 mm outside diameter and 41 mm assembled width T (2.756 × 4.921 × 1.614 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 223 kN, C0 282 kN, Pu 34.5 kN, grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 2120 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33214U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33214U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33214U designation encode the 70 mm bore and what is 3EE?", "a": "last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 125 mm OD and 41 mm assembled T follow the ISO 355 dimension-series plan. 3EE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33214U list two speeds, 2,900 and 3,900 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33214U at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33214U mean?", "a": "Suffix reading on 33214U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33214U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33214u", "3ee", "33214U" ], "locale_variants": {} }, { "sku": "T7FC070", "brand": "NTN", "manufacturer_designation": "NTN T7FC070", "series": "T7FC-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 140, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 191, "static_load_kN": 231, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 2620, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 70 mm shaft with a thrust component, NTN lists T7FC070, a metric 4T tapered roller bearing of 191 kN C and 231 kN C0 inside the 140 mm OD, 39 mm-wide assembled set. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and T7FC070 resolves to 70 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. NTN grades 4T metric bearings as open bearings without integral seals; at 70 mm bore the application supplies the seals and the grease fill or oil supply to the 7FC ISO 355 assembly. Speed planning uses both catalogue columns: grease 2,400 r/min is the cage/rib mechanical ceiling for T7FC070, oil 3,200 r/min is available with circulating oil — a 800 r/min margin at this size. Open 4T bearings need application seals; without them the grease at the cone rib of T7FC070 washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2620 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The large-size ISO 355 tapered-roller family at 70 mm bore (140×39 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,200 r/min oil ceiling.", "Never fit the 70 mm cone by hammering the 140 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume in the 39 mm-wide set; over-greasing a paired bearing churning at the 3,200 r/min oil-band speed raises temperature and destroys the preload setting.", "The 35.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for T7FC070 or the ring will bottom out on the radius instead of the shoulder face.", "The 191/231 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T7FC070 (ISO 355 7FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T7FC070?", "a": "T7FC070 is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 140 mm outside diameter and 39 mm assembled width T (2.756 × 5.512 × 1.535 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 191 kN, C0 231 kN (2203E prints no Pu for this size), grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 2620 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T7FC070?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T7FC070); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T7FC070 designation encode the 70 mm bore and what is 7FC?", "a": "trailing dimension block 070 prints the 70 mm bore directly for this large-size T-code. The 140 mm OD and 39 mm assembled T follow the ISO 355 dimension-series plan. 7FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T7FC070 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T7FC070 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T7FC070 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 70 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T7FC070", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-t7fc070", "7fc", "t7fc070", "T7FC070" ], "locale_variants": {} }, { "sku": "30314D", "brand": "NTN", "manufacturer_designation": "NTN 30314D", "series": "30300-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 150, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 214, "static_load_kN": 229, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3000, "weight_g": 2920, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30314D belongs to the NTN metric 4T tapered roller range (large-OD 30300 family with the steeper contact angle); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30314D resolves to 70 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. The two speed columns differ by a factor of .77 (grease/limiting 2,300 vs oil 3,000 r/min); heat generation at the cone rib decides which lubrication a real 30314D arrangement can sustain. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 30314D arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2920 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 70 mm bore; do not swap to the lighter family without re-checking the 2,300 r/min grease limit and the thrust load split.", "Grease packs must leave free volume in the 38 mm-wide set; over-greasing a paired bearing churning at the 3,000 r/min oil-band speed raises temperature and destroys the preload setting.", "The 40.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30314D or the ring will bottom out on the radius instead of the shoulder face.", "Replacing one half of an adjusted pair without resetting end play negates the 38 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 214/229 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30314D (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30314D?", "a": "30314D is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 150 mm outside diameter and 38 mm assembled width T (2.756 × 5.906 × 1.496 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 214 kN, C0 229 kN (2203E prints no Pu for this size), grease limiting speed 2,300 r/min, oil speed 3,000 r/min, mass about 2920 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30314D?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30314D); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30314D designation encode the 70 mm bore and what is 7GB?", "a": "last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 38 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30314D list two speeds, 2,300 and 3,000 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30314D at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30314D mean?", "a": "Suffix reading on 30314D: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30314D", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30314d", "4t-30314d", "7gb", "30314D" ], "locale_variants": {} }, { "sku": "30314U", "brand": "NTN", "manufacturer_designation": "NTN 30314U", "series": "30300-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 150, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 255, "static_load_kN": 272, "fatigue_load_limit_kN": 32, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 3050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 70 mm bore tapered roller position as 30314U: one cone assembly, one cup, line-contact rollers and a steel cage, rated 255 kN basic dynamic and 272 kN static on the large-OD 30300 family with the steeper contact angle. The last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 38 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 30314U, since running clearance is set during assembly. Speed planning uses both catalogue columns: grease 2,600 r/min is the cage/rib mechanical ceiling for 30314U, oil 3,500 r/min is available with circulating oil — a 900 r/min margin at this size. Mount the 70 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30314U.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3050 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 70 mm bore; do not swap to the lighter family without re-checking the 2,600 r/min grease limit and the thrust load split.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30314U by size alone can deliver the wrong contact-angle execution for a pinion position.", "Replacing one half of an adjusted pair without resetting end play negates the 38 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 70 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 255/272 kN ratings and 32 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30314U (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30314U?", "a": "30314U is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 150 mm outside diameter and 38 mm assembled width T (2.756 × 5.906 × 1.496 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 255 kN, C0 272 kN, Pu 32 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 3050 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30314U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30314U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30314U designation encode the 70 mm bore and what is 2GB?", "a": "last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 38 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30314U list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30314U at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30314U mean?", "a": "Suffix reading on 30314U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30314U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30314u", "30314U" ], "locale_variants": {} }, { "sku": "32314CU", "brand": "NTN", "manufacturer_designation": "NTN 32314CU", "series": "32300-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 150, "B_mm": 54, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 300, "static_load_kN": 380, "fatigue_load_limit_kN": 45, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 4530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 70 mm bore tapered roller position as 32314CU: one cone assembly, one cup, line-contact rollers and a steel cage, rated 300 kN basic dynamic and 380 kN static on the extra-heavy 32300 family. The last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 54 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32314CU, not only the raceway. Selection: C 300 kN against C0 380 kN gives a C0/C ratio of 1.27 for the 70 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 70 mm pair is misadjusted and the 54 mm T set will edge-load in service.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 4530 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 70 mm bore (150×54 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,300 r/min oil ceiling.", "Grease packs must leave free volume in the 54 mm-wide set; over-greasing a paired bearing churning at the 3,300 r/min oil-band speed raises temperature and destroys the preload setting.", "Minimum load matters at high speed: an unloaded 32314CU at a large fraction of 2,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 70 mm shoulder geometry, because retrofitting flips the cups.", "The 300/380 kN ratings and 45 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32314CU (ISO 355 5GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32314CU?", "a": "32314CU is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 150 mm outside diameter and 54 mm assembled width T (2.756 × 5.906 × 2.126 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 300 kN, C0 380 kN, Pu 45 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 4530 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32314CU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32314CU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32314CU designation encode the 70 mm bore and what is 5GD?", "a": "last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 54 mm assembled T follow the ISO 355 dimension-series plan. 5GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32314CU list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32314CU at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32314CU mean?", "a": "Suffix reading on 32314CU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32314CU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32314cu", "5gd", "32314CU" ], "locale_variants": {} }, { "sku": "32314U", "brand": "NTN", "manufacturer_designation": "NTN 32314U", "series": "32300-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 150, "B_mm": 54, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 345, "static_load_kN": 405, "fatigue_load_limit_kN": 48, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 4440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 70 mm bore tapered roller position as 32314U: one cone assembly, one cup, line-contact rollers and a steel cage, rated 345 kN basic dynamic and 405 kN static on the extra-heavy 32300 family. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32314U by the metric ISO 355 number (ISO series abbreviation 2GD): 70 mm bore, 150 mm OD. The 40.0 mm radial section carries the roller complement across the 70–150 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The two speed columns differ by a factor of .74 (grease/limiting 2,600 vs oil 3,500 r/min); heat generation at the cone rib decides which lubrication a real 32314U arrangement can sustain. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 70 mm pair is misadjusted and the 54 mm T set will edge-load in service.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 4440 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 70 mm bore (150×54 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,500 r/min oil ceiling.", "Grease packs must leave free volume in the 54 mm-wide set; over-greasing a paired bearing churning at the 3,500 r/min oil-band speed raises temperature and destroys the preload setting.", "The 40.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32314U or the ring will bottom out on the radius instead of the shoulder face.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32314U by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 345/405 kN ratings and 48 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32314U (ISO 355 2GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32314U?", "a": "32314U is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 150 mm outside diameter and 54 mm assembled width T (2.756 × 5.906 × 2.126 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 345 kN, C0 405 kN, Pu 48 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 4440 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32314U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32314U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32314U designation encode the 70 mm bore and what is 2GD?", "a": "last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 54 mm assembled T follow the ISO 355 dimension-series plan. 2GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32314U list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32314U at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32314U mean?", "a": "Suffix reading on 32314U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32314U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gd", "32314u", "32314U" ], "locale_variants": {} }, { "sku": "32915XU", "brand": "NTN", "manufacturer_designation": "NTN 32915XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 105, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 77, "static_load_kN": 114, "fatigue_load_limit_kN": 13.9, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 508, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32915XU in the extra-light thin-section 32900 family: 75 mm bore, 105 mm cup OD, 20 mm T, with a grease limiting speed of 3,200 r/min and an oil-lubricated ceiling of 4,300 r/min. The last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 20 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32915XU cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The fatigue load limit Pu printed for 32915XU is 13.9 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Fillet radii must clear the ring chamfers of the 105 mm cup and 75 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 508 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 20 mm section of 32915XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 75 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 20 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ISO 355 makes the 75×105 mm envelope interchangeable but not the ratings: NTN prints 77/114 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Do not confuse T (20 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 77/114 kN ratings and 13.9 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32915XU (ISO 355 2BC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32915XU?", "a": "32915XU is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 105 mm outside diameter and 20 mm assembled width T (2.953 × 4.134 × 0.787 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77 kN, C0 114 kN, Pu 13.9 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 508 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32915XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32915XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32915XU designation encode the 75 mm bore and what is 2BC?", "a": "last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table). The 105 mm OD and 20 mm assembled T follow the ISO 355 dimension-series plan. 2BC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32915XU list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32915XU at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32915XU mean?", "a": "Suffix reading on 32915XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32915XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=168", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bc", "32915xu", "32915XU" ], "locale_variants": {} }, { "sku": "32015XU", "brand": "NTN", "manufacturer_designation": "NTN 32015XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 115, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 118, "static_load_kN": 167, "fatigue_load_limit_kN": 20.3, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 912, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32015XU is the NTN 4T catalogue entry for a 75×115×25 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. The last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Selection: C 118 kN against C0 167 kN gives a C0/C ratio of 1.42 for the 75 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32015XU arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 912 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 25 mm section of 32015XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 75 mm bore smears the roller ends against the rib.", "The 20.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32015XU or the ring will bottom out on the radius instead of the shoulder face.", "Grease packs must leave free volume in the 25 mm-wide set; over-greasing a paired bearing churning at the 4,000 r/min oil-band speed raises temperature and destroys the preload setting.", "Replacing one half of an adjusted pair without resetting end play negates the 25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 118/167 kN ratings and 20.3 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32015XU (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32015XU?", "a": "32015XU is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 115 mm outside diameter and 25 mm assembled width T (2.953 × 4.528 × 0.984 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 118 kN, C0 167 kN, Pu 20.3 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 912 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32015XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32015XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32015XU designation encode the 75 mm bore and what is 4CC?", "a": "last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table). The 115 mm OD and 25 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32015XU list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32015XU at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32015XU mean?", "a": "Suffix reading on 32015XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32015XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32015xu", "4cc", "32015XU" ], "locale_variants": {} }, { "sku": "33015U", "brand": "NTN", "manufacturer_designation": "NTN 33015U", "series": "33000-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 115, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 123, "static_load_kN": 186, "fatigue_load_limit_kN": 22.7, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33015U is the NTN 4T catalogue entry for a 75×115×31 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2CE, which is the maker-neutral cross-reference for the 75×115 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The printed contact-angle geometry gives the slim 33000 family its characteristic load split — at 123/186 kN (C/C0) the static rating is about 1.51× C, typical of tapered bearings proportioned for heavy combined duty. The fatigue load limit Pu printed for 33015U is 22.7 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. When pairing 33015U with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1110 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 31 mm section of 33015U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 75 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 31 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 75 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Minimum load matters at high speed: an unloaded 33015U at a large fraction of 3,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 123/186 kN ratings and 22.7 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33015U (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33015U?", "a": "33015U is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 115 mm outside diameter and 31 mm assembled width T (2.953 × 4.528 × 1.22 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 123 kN, C0 186 kN, Pu 22.7 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1110 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33015U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33015U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33015U designation encode the 75 mm bore and what is 2CE?", "a": "last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table). The 115 mm OD and 31 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33015U list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33015U at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33015U mean?", "a": "Suffix reading on 33015U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33015U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "33015u", "33015U" ], "locale_variants": {} }, { "sku": "30215-NTN", "brand": "NTN", "manufacturer_designation": "NTN 30215", "series": "30200-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 130, "B_mm": 27.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 154, "static_load_kN": 175, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30215 is the NTN 4T catalogue entry for a 75×130×27.25 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30215 by the metric ISO 355 number (ISO series abbreviation 4DB): 75 mm bore, 130 mm OD. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Grease relubrication at 2,700 r/min limiting speed targets the rib contact; if the drive needs 3,600 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Fillet radii must clear the ring chamfers of the 130 mm cup and 75 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1400 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The standard-section 30200 family at 75 mm bore (130×27.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,600 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 27.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ISO 355 makes the 75×130 mm envelope interchangeable but not the ratings: NTN prints 154/175 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Replacing one half of an adjusted pair without resetting end play negates the 27.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 154/175 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30215 (ISO 355 4DB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30215?", "a": "30215 is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 130 mm outside diameter and 27.25 mm assembled width T (2.953 × 5.118 × 1.073 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 154 kN, C0 175 kN (2203E prints no Pu for this size), grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 1400 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30215?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30215); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30215 designation encode the 75 mm bore and what is 4DB?", "a": "last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 27.25 mm assembled T follow the ISO 355 dimension-series plan. 4DB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30215 list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30215 at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30215 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "30215", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "30215-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4db", "4t-30215", "30215", "30215-NTN" ], "locale_variants": {} }, { "sku": "32215U", "brand": "NTN", "manufacturer_designation": "NTN 32215U", "series": "32200-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 130, "B_mm": 33.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 186, "static_load_kN": 224, "fatigue_load_limit_kN": 27.1, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 1740, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32215U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 75×130 mm ISO 355 envelope, with 33.25 mm overall assembled width T. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32215U resolves to 75 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32215U cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The 2.5 kN-per-mm-bore capacity figure for 32215U summarises the 186 kN rating over 75 mm bore; use it to sanity-check an interchange candidate before swapping brands. Open 4T bearings need application seals; without them the grease at the cone rib of 32215U washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1740 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The heavy-section 32200 family at 75 mm bore (130×33.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,600 r/min oil ceiling.", "Do not confuse T (33.25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Grease packs must leave free volume in the 33.25 mm-wide set; over-greasing a paired bearing churning at the 3,600 r/min oil-band speed raises temperature and destroys the preload setting.", "Do not confuse T (33.25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 186/224 kN ratings and 27.1 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32215U (ISO 355 4DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32215U?", "a": "32215U is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 130 mm outside diameter and 33.25 mm assembled width T (2.953 × 5.118 × 1.309 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 186 kN, C0 224 kN, Pu 27.1 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 1740 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32215U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32215U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32215U designation encode the 75 mm bore and what is 4DC?", "a": "last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 33.25 mm assembled T follow the ISO 355 dimension-series plan. 4DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32215U list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32215U at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32215U mean?", "a": "Suffix reading on 32215U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32215U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32215u", "4dc", "32215U" ], "locale_variants": {} }, { "sku": "33215U", "brand": "NTN", "manufacturer_designation": "NTN 33215U", "series": "33200-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 130, "B_mm": 41, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 231, "static_load_kN": 298, "fatigue_load_limit_kN": 36, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 2230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33215U belongs to the NTN metric 4T tapered roller range (medium-wide 33200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. The last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 41 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The printed contact-angle geometry gives the medium-wide 33200 family its characteristic load split — at 231/298 kN (C/C0) the static rating is about 1.29× C, typical of tapered bearings proportioned for heavy combined duty. Grease relubrication at 2,700 r/min limiting speed targets the rib contact; if the drive needs 3,600 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 33215U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2230 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The medium-wide 33200 family at 75 mm bore (130×41 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,600 r/min oil ceiling.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33215U by size alone can deliver the wrong contact-angle execution for a pinion position.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 75 mm shoulder geometry, because retrofitting flips the cups.", "Minimum load matters at high speed: an unloaded 33215U at a large fraction of 2,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 231/298 kN ratings and 36 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33215U (ISO 355 3EE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33215U?", "a": "33215U is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 130 mm outside diameter and 41 mm assembled width T (2.953 × 5.118 × 1.614 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 231 kN, C0 298 kN, Pu 36 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 2230 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33215U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33215U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33215U designation encode the 75 mm bore and what is 3EE?", "a": "last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 41 mm assembled T follow the ISO 355 dimension-series plan. 3EE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33215U list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33215U at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33215U mean?", "a": "Suffix reading on 33215U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33215U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33215u", "3ee", "33215U" ], "locale_variants": {} }, { "sku": "30315DU", "brand": "NTN", "manufacturer_designation": "NTN 30315DU", "series": "30300-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 160, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 238, "static_load_kN": 256, "fatigue_load_limit_kN": 29.8, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 3460, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30315DU is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 75×160 mm ISO 355 envelope, with 40 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 7GB, which is the maker-neutral cross-reference for the 75×160 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN grades 4T metric bearings as open bearings without integral seals; at 75 mm bore the application supplies the seals and the grease fill or oil supply to the 7GB ISO 355 assembly. The 3.2 kN-per-mm-bore capacity figure for 30315DU summarises the 238 kN rating over 75 mm bore; use it to sanity-check an interchange candidate before swapping brands. Open 4T bearings need application seals; without them the grease at the cone rib of 30315DU washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3460 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 75 mm bore; do not swap to the lighter family without re-checking the 2,100 r/min grease limit and the thrust load split.", "Grease packs must leave free volume in the 40 mm-wide set; over-greasing a paired bearing churning at the 2,800 r/min oil-band speed raises temperature and destroys the preload setting.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30315DU by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 42.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30315DU or the ring will bottom out on the radius instead of the shoulder face.", "The 238/256 kN ratings and 29.8 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30315DU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30315DU?", "a": "30315DU is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 160 mm outside diameter and 40 mm assembled width T (2.953 × 6.299 × 1.575 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 238 kN, C0 256 kN, Pu 29.8 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 3460 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30315DU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30315DU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30315DU designation encode the 75 mm bore and what is 7GB?", "a": "last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table). The 160 mm OD and 40 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30315DU list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30315DU at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30315DU mean?", "a": "Suffix reading on 30315DU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30315DU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30315du", "7gb", "30315DU" ], "locale_variants": {} }, { "sku": "30315U", "brand": "NTN", "manufacturer_designation": "NTN 30315U", "series": "30300-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 160, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 283, "static_load_kN": 305, "fatigue_load_limit_kN": 35, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 75 mm shaft with a thrust component, NTN lists 30315U, a metric 4T tapered roller bearing of 283 kN C and 305 kN C0 inside the 160 mm OD, 40 mm-wide assembled set. Digit by digit, the bare number identifies the large-OD 30300 family with the steeper contact angle and a bore code resolving to 75 mm; 160 mm OD and 40 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. At 283 kN C the bearing offers about 3.8 kN of dynamic capacity per millimetre of the 75 mm bore — compare any substitution on this ratio and the 40 mm assembled T, not on bore alone. The fatigue load limit Pu printed for 30315U is 35 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. When pairing 30315U with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3610 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 75 mm bore; do not swap to the lighter family without re-checking the 2,400 r/min grease limit and the thrust load split.", "The 42.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30315U or the ring will bottom out on the radius instead of the shoulder face.", "Never fit the 75 mm cone by hammering the 160 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 30315U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 283/305 kN ratings and 35 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30315U (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30315U?", "a": "30315U is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 160 mm outside diameter and 40 mm assembled width T (2.953 × 6.299 × 1.575 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 283 kN, C0 305 kN, Pu 35 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3610 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30315U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30315U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30315U designation encode the 75 mm bore and what is 2GB?", "a": "last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table). The 160 mm OD and 40 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30315U list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30315U at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30315U mean?", "a": "Suffix reading on 30315U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30315U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30315u", "30315U" ], "locale_variants": {} }, { "sku": "32315CU", "brand": "NTN", "manufacturer_designation": "NTN 32315CU", "series": "32300-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 160, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 365, "static_load_kN": 480, "fatigue_load_limit_kN": 56, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 5650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32315CU in the extra-heavy 32300 family: 75 mm bore, 160 mm cup OD, 58 mm T, with a grease limiting speed of 2,300 r/min and an oil-lubricated ceiling of 3,100 r/min. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32315CU by the metric ISO 355 number (ISO series abbreviation 5GD): 75 mm bore, 160 mm OD. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32315CU, since running clearance is set during assembly. Catalogue mass of the 32315CU set is 5650 g (0.222 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. When pairing 32315CU with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 5650 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 75 mm bore (160×58 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,100 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 32315CU at a large fraction of 2,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32315CU by size alone can deliver the wrong contact-angle execution for a pinion position.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 75 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 365/480 kN ratings and 56 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32315CU (ISO 355 5GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32315CU?", "a": "32315CU is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 160 mm outside diameter and 58 mm assembled width T (2.953 × 6.299 × 2.283 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 365 kN, C0 480 kN, Pu 56 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 5650 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32315CU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32315CU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32315CU designation encode the 75 mm bore and what is 5GD?", "a": "last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table). The 160 mm OD and 58 mm assembled T follow the ISO 355 dimension-series plan. 5GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32315CU list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32315CU at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32315CU mean?", "a": "Suffix reading on 32315CU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32315CU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32315cu", "5gd", "32315CU" ], "locale_variants": {} }, { "sku": "32315U", "brand": "NTN", "manufacturer_designation": "NTN 32315U", "series": "32300-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 160, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 395, "static_load_kN": 470, "fatigue_load_limit_kN": 54.5, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 5400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 75 mm shaft with a thrust component, NTN lists 32315U, a metric 4T tapered roller bearing of 395 kN C and 470 kN C0 inside the 160 mm OD, 58 mm-wide assembled set. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2GD, which is the maker-neutral cross-reference for the 75×160 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Selection: C 395 kN against C0 470 kN gives a C0/C ratio of 1.19 for the 75 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 32315U washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 5400 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 75 mm bore (160×58 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,200 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 75 mm shoulder geometry, because retrofitting flips the cups.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 75 mm shoulder geometry, because retrofitting flips the cups.", "Replacing one half of an adjusted pair without resetting end play negates the 58 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 395/470 kN ratings and 54.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32315U (ISO 355 2GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32315U?", "a": "32315U is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 160 mm outside diameter and 58 mm assembled width T (2.953 × 6.299 × 2.283 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 395 kN, C0 470 kN, Pu 54.5 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 5400 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32315U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32315U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32315U designation encode the 75 mm bore and what is 2GD?", "a": "last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table). The 160 mm OD and 58 mm assembled T follow the ISO 355 dimension-series plan. 2GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32315U list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32315U at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32315U mean?", "a": "Suffix reading on 32315U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32315U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gd", "32315u", "32315U" ], "locale_variants": {} }, { "sku": "32916XU", "brand": "NTN", "manufacturer_designation": "NTN 32916XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 110, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 79.5, "static_load_kN": 121, "fatigue_load_limit_kN": 14.8, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 540, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32916XU denotes the extra-light thin-section 32900 family of metric tapered roller bearings, 80 mm bore, 110 mm outside diameter and 20 mm assembled width T (3.15 × 4.331 × 0.787 in) to the ISO 355 boundary plan. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32916XU by the metric ISO 355 number (ISO series abbreviation 2BC): 80 mm bore, 110 mm OD. The printed contact-angle geometry gives the extra-light thin-section 32900 family its characteristic load split — at 79.5/121 kN (C/C0) the static rating is about 1.52× C, typical of tapered bearings proportioned for heavy combined duty. The 1.0 kN-per-mm-bore capacity figure for 32916XU summarises the 79.5 kN rating over 80 mm bore; use it to sanity-check an interchange candidate before swapping brands. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 32916XU; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 540 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 20 mm section of 32916XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 80 mm bore smears the roller ends against the rib.", "Never fit the 80 mm cone by hammering the 110 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (20 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Minimum load matters at high speed: an unloaded 32916XU at a large fraction of 3,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 79.5/121 kN ratings and 14.8 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32916XU (ISO 355 2BC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32916XU?", "a": "32916XU is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 110 mm outside diameter and 20 mm assembled width T (3.15 × 4.331 × 0.787 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 79.5 kN, C0 121 kN, Pu 14.8 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 540 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32916XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32916XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32916XU designation encode the 80 mm bore and what is 2BC?", "a": "last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table). The 110 mm OD and 20 mm assembled T follow the ISO 355 dimension-series plan. 2BC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32916XU list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32916XU at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32916XU mean?", "a": "Suffix reading on 32916XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32916XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bc", "32916xu", "32916XU" ], "locale_variants": {} }, { "sku": "32016XU", "brand": "NTN", "manufacturer_designation": "NTN 32016XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 125, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 154, "static_load_kN": 216, "fatigue_load_limit_kN": 26.1, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3700, "weight_g": 1280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 80 mm shaft with a thrust component, NTN lists 32016XU, a metric 4T tapered roller bearing of 154 kN C and 216 kN C0 inside the 125 mm OD, 29 mm-wide assembled set. Digit by digit, the bare number identifies the low-section 32000 family tuned for low friction and a bore code resolving to 80 mm; 125 mm OD and 29 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. Individually mounted, 32016XU takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The fatigue load limit Pu printed for 32016XU is 26.1 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32016XU arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1280 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 29 mm section of 32016XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 80 mm bore smears the roller ends against the rib.", "Never fit the 80 mm cone by hammering the 125 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32016XU by size alone can deliver the wrong contact-angle execution for a pinion position.", "Never fit the 80 mm cone by hammering the 125 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 154/216 kN ratings and 26.1 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32016XU (ISO 355 3CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32016XU?", "a": "32016XU is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 125 mm outside diameter and 29 mm assembled width T (3.15 × 4.921 × 1.142 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 154 kN, C0 216 kN, Pu 26.1 kN, grease limiting speed 2,800 r/min, oil speed 3,700 r/min, mass about 1280 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32016XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32016XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32016XU designation encode the 80 mm bore and what is 3CC?", "a": "last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table). The 125 mm OD and 29 mm assembled T follow the ISO 355 dimension-series plan. 3CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32016XU list two speeds, 2,800 and 3,700 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32016XU at 3,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32016XU mean?", "a": "Suffix reading on 32016XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32016XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32016xu", "3cc", "32016XU" ], "locale_variants": {} }, { "sku": "33016U", "brand": "NTN", "manufacturer_designation": "NTN 33016U", "series": "33000-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 125, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 192, "static_load_kN": 284, "fatigue_load_limit_kN": 34.5, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3700, "weight_g": 1610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33016U belongs to the NTN metric 4T tapered roller range (slim 33000 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 33016U resolves to 80 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 33016U, since running clearance is set during assembly. Catalogue mass of the 33016U set is 1610 g (0.063 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Fillet radii must clear the ring chamfers of the 125 mm cup and 80 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1610 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 36 mm section of 33016U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 80 mm bore smears the roller ends against the rib.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33016U by size alone can deliver the wrong contact-angle execution for a pinion position.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33016U by size alone can deliver the wrong contact-angle execution for a pinion position.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 80 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 192/284 kN ratings and 34.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33016U (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33016U?", "a": "33016U is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 125 mm outside diameter and 36 mm assembled width T (3.15 × 4.921 × 1.417 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 192 kN, C0 284 kN, Pu 34.5 kN, grease limiting speed 2,800 r/min, oil speed 3,700 r/min, mass about 1610 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33016U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33016U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33016U designation encode the 80 mm bore and what is 2CE?", "a": "last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table). The 125 mm OD and 36 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33016U list two speeds, 2,800 and 3,700 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33016U at 3,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33016U mean?", "a": "Suffix reading on 33016U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33016U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "33016u", "33016U" ], "locale_variants": {} }, { "sku": "33116U", "brand": "NTN", "manufacturer_designation": "NTN 33116U", "series": "33100-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 130, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 199, "static_load_kN": 276, "fatigue_load_limit_kN": 33, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 1870, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 33116U in the light-wide 33100 family: 80 mm bore, 130 mm cup OD, 37 mm T, with a grease limiting speed of 2,700 r/min and an oil-lubricated ceiling of 3,600 r/min. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 33116U by the metric ISO 355 number (ISO series abbreviation 3DE): 80 mm bore, 130 mm OD. The printed contact-angle geometry gives the light-wide 33100 family its characteristic load split — at 199/276 kN (C/C0) the static rating is about 1.39× C, typical of tapered bearings proportioned for heavy combined duty. The 25.0 mm section height over the 80 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Fillet radii must clear the ring chamfers of the 130 mm cup and 80 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1870 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The light-wide 33100 family at 80 mm bore (130×37 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,600 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 80 mm shoulder geometry, because retrofitting flips the cups.", "The 25.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33116U or the ring will bottom out on the radius instead of the shoulder face.", "Minimum load matters at high speed: an unloaded 33116U at a large fraction of 2,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 199/276 kN ratings and 33 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33116U (ISO 355 3DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33116U?", "a": "33116U is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 130 mm outside diameter and 37 mm assembled width T (3.15 × 5.118 × 1.457 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 199 kN, C0 276 kN, Pu 33 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 1870 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33116U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33116U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33116U designation encode the 80 mm bore and what is 3DE?", "a": "last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 37 mm assembled T follow the ISO 355 dimension-series plan. 3DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33116U list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33116U at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33116U mean?", "a": "Suffix reading on 33116U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33116U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33116u", "3de", "33116U" ], "locale_variants": {} }, { "sku": "30216U", "brand": "NTN", "manufacturer_designation": "NTN 30216U", "series": "30200-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 140, "B_mm": 28.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 177, "static_load_kN": 200, "fatigue_load_limit_kN": 23.7, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3400, "weight_g": 1710, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30216U is the NTN 4T catalogue entry for a 80×140×28.25 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3EB, which is the maker-neutral cross-reference for the 80×140 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. 2203E lists two speed ceilings for 30216U: 2,500 r/min with grease lubrication (the limiting speed) and 3,400 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Selection: C 177 kN against C0 200 kN gives a C0/C ratio of 1.13 for the 80 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Fillet radii must clear the ring chamfers of the 140 mm cup and 80 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1710 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The standard-section 30200 family at 80 mm bore (140×28.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,400 r/min oil ceiling.", "Open 30216U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,500 r/min grease figure is meaningless once water reaches the cone rib.", "Open 30216U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,500 r/min grease figure is meaningless once water reaches the cone rib.", "Grease packs must leave free volume in the 28.25 mm-wide set; over-greasing a paired bearing churning at the 3,400 r/min oil-band speed raises temperature and destroys the preload setting.", "The 177/200 kN ratings and 23.7 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30216U (ISO 355 3EB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30216U?", "a": "30216U is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 140 mm outside diameter and 28.25 mm assembled width T (3.15 × 5.512 × 1.112 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 177 kN, C0 200 kN, Pu 23.7 kN, grease limiting speed 2,500 r/min, oil speed 3,400 r/min, mass about 1710 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30216U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30216U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30216U designation encode the 80 mm bore and what is 3EB?", "a": "last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table). The 140 mm OD and 28.25 mm assembled T follow the ISO 355 dimension-series plan. 3EB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30216U list two speeds, 2,500 and 3,400 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30216U at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30216U mean?", "a": "Suffix reading on 30216U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30216U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30216u", "3eb", "30216U" ], "locale_variants": {} }, { "sku": "32216U", "brand": "NTN", "manufacturer_designation": "NTN 32216U", "series": "32200-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 140, "B_mm": 35.25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 221, "static_load_kN": 265, "fatigue_load_limit_kN": 31.5, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3400, "weight_g": 2170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32216U is the NTN 4T catalogue entry for a 80×140×35.25 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. The last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 35.25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The printed contact-angle geometry gives the heavy-section 32200 family its characteristic load split — at 221/265 kN (C/C0) the static rating is about 1.20× C, typical of tapered bearings proportioned for heavy combined duty. Imperial cross-check for the drawing: 80×140×35.25 mm is 3.15 × 5.512 × 1.388 in; ISO 355 makes the envelope interchangeable but C/C0, 221/265 kN, is NTN-specific. Mount the 80 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32216U.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2170 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The heavy-section 32200 family at 80 mm bore (140×35.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,400 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 35.25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Minimum load matters at high speed: an unloaded 32216U at a large fraction of 2,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Minimum load matters at high speed: an unloaded 32216U at a large fraction of 2,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 221/265 kN ratings and 31.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32216U (ISO 355 3EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32216U?", "a": "32216U is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 140 mm outside diameter and 35.25 mm assembled width T (3.15 × 5.512 × 1.388 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 221 kN, C0 265 kN, Pu 31.5 kN, grease limiting speed 2,500 r/min, oil speed 3,400 r/min, mass about 2170 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32216U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32216U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32216U designation encode the 80 mm bore and what is 3EC?", "a": "last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table). The 140 mm OD and 35.25 mm assembled T follow the ISO 355 dimension-series plan. 3EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32216U list two speeds, 2,500 and 3,400 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32216U at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32216U mean?", "a": "Suffix reading on 32216U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32216U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32216u", "3ec", "32216U" ], "locale_variants": {} }, { "sku": "33216U", "brand": "NTN", "manufacturer_designation": "NTN 33216U", "series": "33200-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 140, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 278, "static_load_kN": 365, "fatigue_load_limit_kN": 43.5, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3400, "weight_g": 2940, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 80 mm bore tapered roller position as 33216U: one cone assembly, one cup, line-contact rollers and a steel cage, rated 278 kN basic dynamic and 365 kN static on the medium-wide 33200 family. Digit by digit, the bare number identifies the medium-wide 33200 family and a bore code resolving to 80 mm; 140 mm OD and 46 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 33216U, since running clearance is set during assembly. The 3.5 kN-per-mm-bore capacity figure for 33216U summarises the 278 kN rating over 80 mm bore; use it to sanity-check an interchange candidate before swapping brands. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 80 mm pair is misadjusted and the 46 mm T set will edge-load in service.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2940 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The medium-wide 33200 family at 80 mm bore (140×46 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,400 r/min oil ceiling.", "The 30.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33216U or the ring will bottom out on the radius instead of the shoulder face.", "Do not confuse T (46 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 80 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 278/365 kN ratings and 43.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33216U (ISO 355 3EE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33216U?", "a": "33216U is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 140 mm outside diameter and 46 mm assembled width T (3.15 × 5.512 × 1.811 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 278 kN, C0 365 kN, Pu 43.5 kN, grease limiting speed 2,500 r/min, oil speed 3,400 r/min, mass about 2940 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33216U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33216U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33216U designation encode the 80 mm bore and what is 3EE?", "a": "last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table). The 140 mm OD and 46 mm assembled T follow the ISO 355 dimension-series plan. 3EE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33216U list two speeds, 2,500 and 3,400 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33216U at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33216U mean?", "a": "Suffix reading on 33216U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33216U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33216u", "3ee", "33216U" ], "locale_variants": {} }, { "sku": "T7FC080", "brand": "NTN", "manufacturer_designation": "NTN T7FC080", "series": "T7FC-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 160, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 238, "static_load_kN": 297, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3920, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number T7FC080 denotes the large-size ISO 355 tapered-roller family of metric tapered roller bearings, 80 mm bore, 160 mm outside diameter and 45 mm assembled width T (3.15 × 6.299 × 1.772 in) to the ISO 355 boundary plan. The trailing dimension block 080 prints the 80 mm bore directly for this large-size T-code under the ISO 355 numbering; the 45 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The 40.0 mm radial section carries the roller complement across the 80–160 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. 2203E does not print a Pu fatigue load limit for T7FC080; life work for this size uses the 238/297 kN C/C0 pair directly. Mount the 80 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of T7FC080.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3920 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The large-size ISO 355 tapered-roller family at 80 mm bore (160×45 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,200 r/min oil ceiling.", "Grease packs must leave free volume in the 45 mm-wide set; over-greasing a paired bearing churning at the 3,200 r/min oil-band speed raises temperature and destroys the preload setting.", "Minimum load matters at high speed: an unloaded T7FC080 at a large fraction of 2,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering T7FC080 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 238/297 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T7FC080 (ISO 355 7FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T7FC080?", "a": "T7FC080 is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 160 mm outside diameter and 45 mm assembled width T (3.15 × 6.299 × 1.772 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 238 kN, C0 297 kN (2203E prints no Pu for this size), grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3920 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T7FC080?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T7FC080); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T7FC080 designation encode the 80 mm bore and what is 7FC?", "a": "trailing dimension block 080 prints the 80 mm bore directly for this large-size T-code. The 160 mm OD and 45 mm assembled T follow the ISO 355 dimension-series plan. 7FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T7FC080 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T7FC080 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T7FC080 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 80 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T7FC080", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-t7fc080", "7fc", "t7fc080", "T7FC080" ], "locale_variants": {} }, { "sku": "30316DU", "brand": "NTN", "manufacturer_designation": "NTN 30316DU", "series": "30300-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 170, "B_mm": 42.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 262, "static_load_kN": 283, "fatigue_load_limit_kN": 32.5, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2700, "weight_g": 4170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30316DU in the large-OD 30300 family with the steeper contact angle: 80 mm bore, 170 mm cup OD, 42.5 mm T, with a grease limiting speed of 2,000 r/min and an oil-lubricated ceiling of 2,700 r/min. The last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 42.5 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 30316DU cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Selection: C 262 kN against C0 283 kN gives a C0/C ratio of 1.08 for the 80 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 30316DU; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 4170 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 80 mm bore; do not swap to the lighter family without re-checking the 2,000 r/min grease limit and the thrust load split.", "Minimum load matters at high speed: an unloaded 30316DU at a large fraction of 2,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Never fit the 80 mm cone by hammering the 170 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (42.5 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 262/283 kN ratings and 32.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30316DU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30316DU?", "a": "30316DU is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 170 mm outside diameter and 42.5 mm assembled width T (3.15 × 6.693 × 1.673 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 262 kN, C0 283 kN, Pu 32.5 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 4170 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30316DU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30316DU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30316DU designation encode the 80 mm bore and what is 7GB?", "a": "last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table). The 170 mm OD and 42.5 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30316DU list two speeds, 2,000 and 2,700 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30316DU at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30316DU mean?", "a": "Suffix reading on 30316DU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30316DU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30316du", "7gb", "30316DU" ], "locale_variants": {} }, { "sku": "30316U", "brand": "NTN", "manufacturer_designation": "NTN 30316U", "series": "30300-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 170, "B_mm": 42.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 325, "static_load_kN": 350, "fatigue_load_limit_kN": 39.5, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3000, "weight_g": 4410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 30316U denotes the large-OD 30300 family with the steeper contact angle of metric tapered roller bearings, 80 mm bore, 170 mm outside diameter and 42.5 mm assembled width T (3.15 × 6.693 × 1.673 in) to the ISO 355 boundary plan. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30316U by the metric ISO 355 number (ISO series abbreviation 2GB): 80 mm bore, 170 mm OD. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 30316U, not only the raceway. Catalogue mass of the 30316U set is 4410 g (0.174 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Fillet radii must clear the ring chamfers of the 170 mm cup and 80 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 4410 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 80 mm bore; do not swap to the lighter family without re-checking the 2,300 r/min grease limit and the thrust load split.", "ISO 355 makes the 80×170 mm envelope interchangeable but not the ratings: NTN prints 325/350 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 80 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 80 mm shoulder geometry, because retrofitting flips the cups.", "The 325/350 kN ratings and 39.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30316U (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30316U?", "a": "30316U is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 170 mm outside diameter and 42.5 mm assembled width T (3.15 × 6.693 × 1.673 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 325 kN, C0 350 kN, Pu 39.5 kN, grease limiting speed 2,300 r/min, oil speed 3,000 r/min, mass about 4410 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30316U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30316U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30316U designation encode the 80 mm bore and what is 2GB?", "a": "last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table). The 170 mm OD and 42.5 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30316U list two speeds, 2,300 and 3,000 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30316U at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30316U mean?", "a": "Suffix reading on 30316U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30316U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30316u", "30316U" ], "locale_variants": {} }, { "sku": "32316CU", "brand": "NTN", "manufacturer_designation": "NTN 32316CU", "series": "32300-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 170, "B_mm": 61.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 390, "static_load_kN": 505, "fatigue_load_limit_kN": 58, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 2900, "weight_g": 6610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32316CU belongs to the NTN metric 4T tapered roller range (extra-heavy 32300 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32316CU resolves to 80 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The 45.0 mm radial section carries the roller complement across the 80–170 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Imperial cross-check for the drawing: 80×170×61.5 mm is 3.15 × 6.693 × 2.421 in; ISO 355 makes the envelope interchangeable but C/C0, 390/505 kN, is NTN-specific. When pairing 32316CU with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 6610 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 80 mm bore (170×61.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,900 r/min oil ceiling.", "The 45.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32316CU or the ring will bottom out on the radius instead of the shoulder face.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 80 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32316CU by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 390/505 kN ratings and 58 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32316CU (ISO 355 5GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32316CU?", "a": "32316CU is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 170 mm outside diameter and 61.5 mm assembled width T (3.15 × 6.693 × 2.421 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 390 kN, C0 505 kN, Pu 58 kN, grease limiting speed 2,200 r/min, oil speed 2,900 r/min, mass about 6610 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32316CU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32316CU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32316CU designation encode the 80 mm bore and what is 5GD?", "a": "last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table). The 170 mm OD and 61.5 mm assembled T follow the ISO 355 dimension-series plan. 5GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32316CU list two speeds, 2,200 and 2,900 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32316CU at 2,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32316CU mean?", "a": "Suffix reading on 32316CU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32316CU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32316cu", "5gd", "32316CU" ], "locale_variants": {} }, { "sku": "32316U", "brand": "NTN", "manufacturer_designation": "NTN 32316U", "series": "32300-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 170, "B_mm": 61.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 440, "static_load_kN": 525, "fatigue_load_limit_kN": 60, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3000, "weight_g": 6480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32316U denotes the extra-heavy 32300 family of metric tapered roller bearings, 80 mm bore, 170 mm outside diameter and 61.5 mm assembled width T (3.15 × 6.693 × 2.421 in) to the ISO 355 boundary plan. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32316U resolves to 80 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32316U cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Speed planning uses both catalogue columns: grease 2,300 r/min is the cage/rib mechanical ceiling for 32316U, oil 3,000 r/min is available with circulating oil — a 700 r/min margin at this size. Mount the 80 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32316U.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 6480 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 80 mm bore (170×61.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,000 r/min oil ceiling.", "Open 32316U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,300 r/min grease figure is meaningless once water reaches the cone rib.", "Do not confuse T (61.5 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Do not confuse T (61.5 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 440/525 kN ratings and 60 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32316U (ISO 355 2GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32316U?", "a": "32316U is a metric 4T tapered roller bearing to ISO 355: 80 mm bore, 170 mm outside diameter and 61.5 mm assembled width T (3.15 × 6.693 × 2.421 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 440 kN, C0 525 kN, Pu 60 kN, grease limiting speed 2,300 r/min, oil speed 3,000 r/min, mass about 6480 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32316U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32316U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32316U designation encode the 80 mm bore and what is 2GD?", "a": "last two digits 16 are the ISO bore code, ×5 = 80 mm (codes 00–03 use the 10/12/15/17 exception table). The 170 mm OD and 61.5 mm assembled T follow the ISO 355 dimension-series plan. 2GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32316U list two speeds, 2,300 and 3,000 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32316U at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32316U mean?", "a": "Suffix reading on 32316U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32316U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gd", "32316u", "32316U" ], "locale_variants": {} }, { "sku": "32917XU", "brand": "NTN", "manufacturer_designation": "NTN 32917XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 120, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 104, "static_load_kN": 157, "fatigue_load_limit_kN": 19.1, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3800, "weight_g": 773, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32917XU is the NTN 4T catalogue entry for a 85×120×23 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2BC, which is the maker-neutral cross-reference for the 85×120 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Imperial cross-check for the drawing: 85×120×23 mm is 3.346 × 4.724 × 0.906 in; ISO 355 makes the envelope interchangeable but C/C0, 104/157 kN, is NTN-specific. Mount the 85 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32917XU.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 773 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 23 mm section of 32917XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 85 mm bore smears the roller ends against the rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 85 mm shoulder geometry, because retrofitting flips the cups.", "The 17.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32917XU or the ring will bottom out on the radius instead of the shoulder face.", "Replacing one half of an adjusted pair without resetting end play negates the 23 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 104/157 kN ratings and 19.1 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32917XU (ISO 355 2BC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32917XU?", "a": "32917XU is a metric 4T tapered roller bearing to ISO 355: 85 mm bore, 120 mm outside diameter and 23 mm assembled width T (3.346 × 4.724 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 104 kN, C0 157 kN, Pu 19.1 kN, grease limiting speed 2,800 r/min, oil speed 3,800 r/min, mass about 773 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32917XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32917XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32917XU designation encode the 85 mm bore and what is 2BC?", "a": "last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table). The 120 mm OD and 23 mm assembled T follow the ISO 355 dimension-series plan. 2BC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32917XU list two speeds, 2,800 and 3,800 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32917XU at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32917XU mean?", "a": "Suffix reading on 32917XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32917XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bc", "32917xu", "32917XU" ], "locale_variants": {} }, { "sku": "32017XU", "brand": "NTN", "manufacturer_designation": "NTN 32017XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 130, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 157, "static_load_kN": 224, "fatigue_load_limit_kN": 26.7, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32017XU is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 85×130 mm ISO 355 envelope, with 29 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4CC, which is the maker-neutral cross-reference for the 85×130 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32017XU, not only the raceway. Grease relubrication at 2,600 r/min limiting speed targets the rib contact; if the drive needs 3,500 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Open 4T bearings need application seals; without them the grease at the cone rib of 32017XU washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1340 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 29 mm section of 32017XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 85 mm bore smears the roller ends against the rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 85 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Never fit the 85 mm cone by hammering the 130 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 85 mm shoulder geometry, because retrofitting flips the cups.", "The 157/224 kN ratings and 26.7 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32017XU (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32017XU?", "a": "32017XU is a metric 4T tapered roller bearing to ISO 355: 85 mm bore, 130 mm outside diameter and 29 mm assembled width T (3.346 × 5.118 × 1.142 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 157 kN, C0 224 kN, Pu 26.7 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1340 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32017XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32017XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32017XU designation encode the 85 mm bore and what is 4CC?", "a": "last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 29 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32017XU list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32017XU at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32017XU mean?", "a": "Suffix reading on 32017XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32017XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32017xu", "4cc", "32017XU" ], "locale_variants": {} }, { "sku": "33017U", "brand": "NTN", "manufacturer_designation": "NTN 33017U", "series": "33000-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 130, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 195, "static_load_kN": 296, "fatigue_load_limit_kN": 35.5, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 85 mm bore tapered roller position as 33017U: one cone assembly, one cup, line-contact rollers and a steel cage, rated 195 kN basic dynamic and 296 kN static on the slim 33000 family. The last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 36 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. At 195 kN C the bearing offers about 2.3 kN of dynamic capacity per millimetre of the 85 mm bore — compare any substitution on this ratio and the 36 mm assembled T, not on bore alone. The 22.5 mm section height over the 85 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 33017U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1690 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 36 mm section of 33017U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 85 mm bore smears the roller ends against the rib.", "The 22.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33017U or the ring will bottom out on the radius instead of the shoulder face.", "Grease packs must leave free volume in the 36 mm-wide set; over-greasing a paired bearing churning at the 3,500 r/min oil-band speed raises temperature and destroys the preload setting.", "Open 33017U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 195/296 kN ratings and 35.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33017U (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33017U?", "a": "33017U is a metric 4T tapered roller bearing to ISO 355: 85 mm bore, 130 mm outside diameter and 36 mm assembled width T (3.346 × 5.118 × 1.417 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 195 kN, C0 296 kN, Pu 35.5 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1690 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33017U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33017U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33017U designation encode the 85 mm bore and what is 2CE?", "a": "last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 36 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33017U list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33017U at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33017U mean?", "a": "Suffix reading on 33017U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33017U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "33017u", "33017U" ], "locale_variants": {} }, { "sku": "33117U", "brand": "NTN", "manufacturer_designation": "NTN 33117U", "series": "33100-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 140, "B_mm": 41, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 234, "static_load_kN": 330, "fatigue_load_limit_kN": 39, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3400, "weight_g": 2440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33117U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 85×140 mm ISO 355 envelope, with 41 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3DE, which is the maker-neutral cross-reference for the 85×140 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 33117U, since running clearance is set during assembly. Grease relubrication at 2,500 r/min limiting speed targets the rib contact; if the drive needs 3,400 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 33117U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2440 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The light-wide 33100 family at 85 mm bore (140×41 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,400 r/min oil ceiling.", "Open 33117U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,500 r/min grease figure is meaningless once water reaches the cone rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 85 mm shoulder geometry, because retrofitting flips the cups.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 85 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 234/330 kN ratings and 39 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33117U (ISO 355 3DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33117U?", "a": "33117U is a metric 4T tapered roller bearing to ISO 355: 85 mm bore, 140 mm outside diameter and 41 mm assembled width T (3.346 × 5.512 × 1.614 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 234 kN, C0 330 kN, Pu 39 kN, grease limiting speed 2,500 r/min, oil speed 3,400 r/min, mass about 2440 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33117U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33117U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33117U designation encode the 85 mm bore and what is 3DE?", "a": "last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table). The 140 mm OD and 41 mm assembled T follow the ISO 355 dimension-series plan. 3DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33117U list two speeds, 2,500 and 3,400 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33117U at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33117U mean?", "a": "Suffix reading on 33117U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33117U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33117u", "3de", "33117U" ], "locale_variants": {} }, { "sku": "30217U", "brand": "NTN", "manufacturer_designation": "NTN 30217U", "series": "30200-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 150, "B_mm": 30.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 203, "static_load_kN": 232, "fatigue_load_limit_kN": 27, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 2130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30217U belongs to the NTN metric 4T tapered roller range (standard-section 30200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30217U resolves to 85 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Individually mounted, 30217U takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Speed planning uses both catalogue columns: grease 2,400 r/min is the cage/rib mechanical ceiling for 30217U, oil 3,200 r/min is available with circulating oil — a 800 r/min margin at this size. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 30217U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2130 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The standard-section 30200 family at 85 mm bore (150×30.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,200 r/min oil ceiling.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 85 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Replacing one half of an adjusted pair without resetting end play negates the 30.5 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never fit the 85 mm cone by hammering the 150 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 203/232 kN ratings and 27 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30217U (ISO 355 3EB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30217U?", "a": "30217U is a metric 4T tapered roller bearing to ISO 355: 85 mm bore, 150 mm outside diameter and 30.5 mm assembled width T (3.346 × 5.906 × 1.201 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 203 kN, C0 232 kN, Pu 27 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 2130 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30217U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30217U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30217U designation encode the 85 mm bore and what is 3EB?", "a": "last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 30.5 mm assembled T follow the ISO 355 dimension-series plan. 3EB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30217U list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30217U at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30217U mean?", "a": "Suffix reading on 30217U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30217U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30217u", "3eb", "30217U" ], "locale_variants": {} }, { "sku": "32217U", "brand": "NTN", "manufacturer_designation": "NTN 32217U", "series": "32200-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 150, "B_mm": 38.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 249, "static_load_kN": 300, "fatigue_load_limit_kN": 35, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 2750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32217U belongs to the NTN metric 4T tapered roller range (heavy-section 32200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Digit by digit, the bare number identifies the heavy-section 32200 family and a bore code resolving to 85 mm; 150 mm OD and 38.5 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32217U, since running clearance is set during assembly. The two speed columns differ by a factor of .75 (grease/limiting 2,400 vs oil 3,200 r/min); heat generation at the cone rib decides which lubrication a real 32217U arrangement can sustain. When pairing 32217U with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2750 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The heavy-section 32200 family at 85 mm bore (150×38.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,200 r/min oil ceiling.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32217U by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 32.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32217U or the ring will bottom out on the radius instead of the shoulder face.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 85 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 249/300 kN ratings and 35 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32217U (ISO 355 3EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32217U?", "a": "32217U is a metric 4T tapered roller bearing to ISO 355: 85 mm bore, 150 mm outside diameter and 38.5 mm assembled width T (3.346 × 5.906 × 1.516 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 249 kN, C0 300 kN, Pu 35 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 2750 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32217U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32217U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32217U designation encode the 85 mm bore and what is 3EC?", "a": "last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 38.5 mm assembled T follow the ISO 355 dimension-series plan. 3EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32217U list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32217U at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32217U mean?", "a": "Suffix reading on 32217U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32217U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32217u", "3ec", "32217U" ], "locale_variants": {} }, { "sku": "33217U", "brand": "NTN", "manufacturer_designation": "NTN 33217U", "series": "33200-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 150, "B_mm": 49, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 315, "static_load_kN": 420, "fatigue_load_limit_kN": 49, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 85 mm shaft with a thrust component, NTN lists 33217U, a metric 4T tapered roller bearing of 315 kN C and 420 kN C0 inside the 150 mm OD, 49 mm-wide assembled set. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 33217U by the metric ISO 355 number (ISO series abbreviation 3EE): 85 mm bore, 150 mm OD. At 315 kN C the bearing offers about 3.7 kN of dynamic capacity per millimetre of the 85 mm bore — compare any substitution on this ratio and the 49 mm assembled T, not on bore alone. Imperial cross-check for the drawing: 85×150×49 mm is 3.346 × 5.906 × 1.929 in; ISO 355 makes the envelope interchangeable but C/C0, 315/420 kN, is NTN-specific. Open 4T bearings need application seals; without them the grease at the cone rib of 33217U washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3610 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The medium-wide 33200 family at 85 mm bore (150×49 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,200 r/min oil ceiling.", "ISO 355 makes the 85×150 mm envelope interchangeable but not the ratings: NTN prints 315/420 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "ISO 355 makes the 85×150 mm envelope interchangeable but not the ratings: NTN prints 315/420 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Open 33217U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 315/420 kN ratings and 49 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33217U (ISO 355 3EE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33217U?", "a": "33217U is a metric 4T tapered roller bearing to ISO 355: 85 mm bore, 150 mm outside diameter and 49 mm assembled width T (3.346 × 5.906 × 1.929 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 315 kN, C0 420 kN, Pu 49 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3610 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33217U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33217U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33217U designation encode the 85 mm bore and what is 3EE?", "a": "last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 49 mm assembled T follow the ISO 355 dimension-series plan. 3EE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33217U list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33217U at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33217U mean?", "a": "Suffix reading on 33217U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33217U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33217u", "3ee", "33217U" ], "locale_variants": {} }, { "sku": "30317DU", "brand": "NTN", "manufacturer_designation": "NTN 30317DU", "series": "30300-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 180, "B_mm": 44.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 274, "static_load_kN": 293, "fatigue_load_limit_kN": 33, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2500, "weight_g": 4740, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30317DU belongs to the NTN metric 4T tapered roller range (large-OD 30300 family with the steeper contact angle); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30317DU by the metric ISO 355 number (ISO series abbreviation 7GB): 85 mm bore, 180 mm OD. Suffix reading on 30317DU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles. The 47.5 mm section height over the 85 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 30317DU; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 4740 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 85 mm bore; do not swap to the lighter family without re-checking the 1,900 r/min grease limit and the thrust load split.", "The 47.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30317DU or the ring will bottom out on the radius instead of the shoulder face.", "Replacing one half of an adjusted pair without resetting end play negates the 44.5 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ISO 355 makes the 85×180 mm envelope interchangeable but not the ratings: NTN prints 274/293 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 274/293 kN ratings and 33 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30317DU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30317DU?", "a": "30317DU is a metric 4T tapered roller bearing to ISO 355: 85 mm bore, 180 mm outside diameter and 44.5 mm assembled width T (3.346 × 7.087 × 1.752 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 274 kN, C0 293 kN, Pu 33 kN, grease limiting speed 1,900 r/min, oil speed 2,500 r/min, mass about 4740 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30317DU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30317DU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30317DU designation encode the 85 mm bore and what is 7GB?", "a": "last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 44.5 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30317DU list two speeds, 1,900 and 2,500 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30317DU at 2,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30317DU mean?", "a": "Suffix reading on 30317DU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30317DU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30317du", "7gb", "30317DU" ], "locale_variants": {} }, { "sku": "30317U", "brand": "NTN", "manufacturer_designation": "NTN 30317U", "series": "30300-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 180, "B_mm": 44.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 335, "static_load_kN": 365, "fatigue_load_limit_kN": 40.5, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2900, "weight_g": 5010, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30317U in the large-OD 30300 family with the steeper contact angle: 85 mm bore, 180 mm cup OD, 44.5 mm T, with a grease limiting speed of 2,100 r/min and an oil-lubricated ceiling of 2,900 r/min. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2GB, which is the maker-neutral cross-reference for the 85×180 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. 2203E lists two speed ceilings for 30317U: 2,100 r/min with grease lubrication (the limiting speed) and 2,900 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. The 47.5 mm section height over the 85 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 30317U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 5010 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 85 mm bore; do not swap to the lighter family without re-checking the 2,100 r/min grease limit and the thrust load split.", "Never fit the 85 mm cone by hammering the 180 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30317U by size alone can deliver the wrong contact-angle execution for a pinion position.", "Grease packs must leave free volume in the 44.5 mm-wide set; over-greasing a paired bearing churning at the 2,900 r/min oil-band speed raises temperature and destroys the preload setting.", "The 335/365 kN ratings and 40.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30317U (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30317U?", "a": "30317U is a metric 4T tapered roller bearing to ISO 355: 85 mm bore, 180 mm outside diameter and 44.5 mm assembled width T (3.346 × 7.087 × 1.752 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 335 kN, C0 365 kN, Pu 40.5 kN, grease limiting speed 2,100 r/min, oil speed 2,900 r/min, mass about 5010 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30317U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30317U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30317U designation encode the 85 mm bore and what is 2GB?", "a": "last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 44.5 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30317U list two speeds, 2,100 and 2,900 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30317U at 2,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30317U mean?", "a": "Suffix reading on 30317U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30317U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30317u", "30317U" ], "locale_variants": {} }, { "sku": "32317CU", "brand": "NTN", "manufacturer_designation": "NTN 32317CU", "series": "32300-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 180, "B_mm": 63.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 435, "static_load_kN": 575, "fatigue_load_limit_kN": 64.5, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2700, "weight_g": 7710, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32317CU denotes the extra-heavy 32300 family of metric tapered roller bearings, 85 mm bore, 180 mm outside diameter and 63.5 mm assembled width T (3.346 × 7.087 × 2.5 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the extra-heavy 32300 family and a bore code resolving to 85 mm; 180 mm OD and 63.5 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. 2203E lists two speed ceilings for 32317CU: 2,100 r/min with grease lubrication (the limiting speed) and 2,700 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. The fatigue load limit Pu printed for 32317CU is 64.5 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. When pairing 32317CU with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 7710 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 85 mm bore (180×63.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,700 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 85 mm shoulder geometry, because retrofitting flips the cups.", "Never fit the 85 mm cone by hammering the 180 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume in the 63.5 mm-wide set; over-greasing a paired bearing churning at the 2,700 r/min oil-band speed raises temperature and destroys the preload setting.", "The 435/575 kN ratings and 64.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32317CU (ISO 355 5GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32317CU?", "a": "32317CU is a metric 4T tapered roller bearing to ISO 355: 85 mm bore, 180 mm outside diameter and 63.5 mm assembled width T (3.346 × 7.087 × 2.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 435 kN, C0 575 kN, Pu 64.5 kN, grease limiting speed 2,100 r/min, oil speed 2,700 r/min, mass about 7710 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32317CU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32317CU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32317CU designation encode the 85 mm bore and what is 5GD?", "a": "last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 63.5 mm assembled T follow the ISO 355 dimension-series plan. 5GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32317CU list two speeds, 2,100 and 2,700 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32317CU at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32317CU mean?", "a": "Suffix reading on 32317CU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32317CU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32317cu", "5gd", "32317CU" ], "locale_variants": {} }, { "sku": "32317U", "brand": "NTN", "manufacturer_designation": "NTN 32317U", "series": "32300-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 180, "B_mm": 63.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 445, "static_load_kN": 525, "fatigue_load_limit_kN": 59, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2900, "weight_g": 7220, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32317U in the extra-heavy 32300 family: 85 mm bore, 180 mm cup OD, 63.5 mm T, with a grease limiting speed of 2,100 r/min and an oil-lubricated ceiling of 2,900 r/min. The last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 63.5 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The printed contact-angle geometry gives the extra-heavy 32300 family its characteristic load split — at 445/525 kN (C/C0) the static rating is about 1.18× C, typical of tapered bearings proportioned for heavy combined duty. The fatigue load limit Pu printed for 32317U is 59 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. When pairing 32317U with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 7220 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 85 mm bore (180×63.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,900 r/min oil ceiling.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 85 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "ISO 355 makes the 85×180 mm envelope interchangeable but not the ratings: NTN prints 445/525 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Minimum load matters at high speed: an unloaded 32317U at a large fraction of 2,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 445/525 kN ratings and 59 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32317U (ISO 355 2GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32317U?", "a": "32317U is a metric 4T tapered roller bearing to ISO 355: 85 mm bore, 180 mm outside diameter and 63.5 mm assembled width T (3.346 × 7.087 × 2.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 445 kN, C0 525 kN, Pu 59 kN, grease limiting speed 2,100 r/min, oil speed 2,900 r/min, mass about 7220 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32317U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32317U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32317U designation encode the 85 mm bore and what is 2GD?", "a": "last two digits 17 are the ISO bore code, ×5 = 85 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 63.5 mm assembled T follow the ISO 355 dimension-series plan. 2GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32317U list two speeds, 2,100 and 2,900 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32317U at 2,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32317U mean?", "a": "Suffix reading on 32317U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32317U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gd", "32317u", "32317U" ], "locale_variants": {} }, { "sku": "32918XU", "brand": "NTN", "manufacturer_designation": "NTN 32918XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 125, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 108, "static_load_kN": 168, "fatigue_load_limit_kN": 20, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 815, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 90 mm shaft with a thrust component, NTN lists 32918XU, a metric 4T tapered roller bearing of 108 kN C and 168 kN C0 inside the 125 mm OD, 23 mm-wide assembled set. The last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 23 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Individually mounted, 32918XU takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The fatigue load limit Pu printed for 32918XU is 20 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Mount the 90 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32918XU.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 815 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 23 mm section of 32918XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 90 mm bore smears the roller ends against the rib.", "Do not confuse T (23 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Minimum load matters at high speed: an unloaded 32918XU at a large fraction of 2,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Never fit the 90 mm cone by hammering the 125 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 108/168 kN ratings and 20 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32918XU (ISO 355 2BC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32918XU?", "a": "32918XU is a metric 4T tapered roller bearing to ISO 355: 90 mm bore, 125 mm outside diameter and 23 mm assembled width T (3.543 × 4.921 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 108 kN, C0 168 kN, Pu 20 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 815 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32918XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32918XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32918XU designation encode the 90 mm bore and what is 2BC?", "a": "last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table). The 125 mm OD and 23 mm assembled T follow the ISO 355 dimension-series plan. 2BC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32918XU list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32918XU at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32918XU mean?", "a": "Suffix reading on 32918XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32918XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bc", "32918xu", "32918XU" ], "locale_variants": {} }, { "sku": "32018XU", "brand": "NTN", "manufacturer_designation": "NTN 32018XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 140, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 187, "static_load_kN": 270, "fatigue_load_limit_kN": 31.5, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 1780, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 90 mm bore tapered roller position as 32018XU: one cone assembly, one cup, line-contact rollers and a steel cage, rated 187 kN basic dynamic and 270 kN static on the low-section 32000 family tuned for low friction. The last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 32 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32018XU cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Selection: C 187 kN against C0 270 kN gives a C0/C ratio of 1.44 for the 90 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 32018XU washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1780 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 32 mm section of 32018XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 90 mm bore smears the roller ends against the rib.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32018XU by size alone can deliver the wrong contact-angle execution for a pinion position.", "Replacing one half of an adjusted pair without resetting end play negates the 32 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (32 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 187/270 kN ratings and 31.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32018XU (ISO 355 3CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32018XU?", "a": "32018XU is a metric 4T tapered roller bearing to ISO 355: 90 mm bore, 140 mm outside diameter and 32 mm assembled width T (3.543 × 5.512 × 1.26 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 187 kN, C0 270 kN, Pu 31.5 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 1780 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32018XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32018XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32018XU designation encode the 90 mm bore and what is 3CC?", "a": "last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table). The 140 mm OD and 32 mm assembled T follow the ISO 355 dimension-series plan. 3CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32018XU list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32018XU at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32018XU mean?", "a": "Suffix reading on 32018XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32018XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32018xu", "3cc", "32018XU" ], "locale_variants": {} }, { "sku": "33018U", "brand": "NTN", "manufacturer_designation": "NTN 33018U", "series": "33000-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 140, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 238, "static_load_kN": 360, "fatigue_load_limit_kN": 42, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 2220, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 90 mm shaft with a thrust component, NTN lists 33018U, a metric 4T tapered roller bearing of 238 kN C and 360 kN C0 inside the 140 mm OD, 39 mm-wide assembled set. The last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 39 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 33018U, not only the raceway. Catalogue mass of the 33018U set is 2220 g (0.087 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 33018U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2220 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 39 mm section of 33018U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 90 mm bore smears the roller ends against the rib.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33018U by size alone can deliver the wrong contact-angle execution for a pinion position.", "Minimum load matters at high speed: an unloaded 33018U at a large fraction of 2,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 90 mm shoulder geometry, because retrofitting flips the cups.", "The 238/360 kN ratings and 42 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33018U (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33018U?", "a": "33018U is a metric 4T tapered roller bearing to ISO 355: 90 mm bore, 140 mm outside diameter and 39 mm assembled width T (3.543 × 5.512 × 1.535 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 238 kN, C0 360 kN, Pu 42 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 2220 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33018U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33018U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33018U designation encode the 90 mm bore and what is 2CE?", "a": "last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table). The 140 mm OD and 39 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33018U list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33018U at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33018U mean?", "a": "Suffix reading on 33018U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33018U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "33018u", "33018U" ], "locale_variants": {} }, { "sku": "33118U", "brand": "NTN", "manufacturer_designation": "NTN 33118U", "series": "33100-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 150, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 280, "static_load_kN": 400, "fatigue_load_limit_kN": 46, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33118U is the NTN 4T catalogue entry for a 90×150×45 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 33118U resolves to 90 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. At 280 kN C the bearing offers about 3.1 kN of dynamic capacity per millimetre of the 90 mm bore — compare any substitution on this ratio and the 45 mm assembled T, not on bore alone. The 3.1 kN-per-mm-bore capacity figure for 33118U summarises the 280 kN rating over 90 mm bore; use it to sanity-check an interchange candidate before swapping brands. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 33118U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3100 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The light-wide 33100 family at 90 mm bore (150×45 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,200 r/min oil ceiling.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 90 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Do not confuse T (45 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Open 33118U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 280/400 kN ratings and 46 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33118U (ISO 355 3DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33118U?", "a": "33118U is a metric 4T tapered roller bearing to ISO 355: 90 mm bore, 150 mm outside diameter and 45 mm assembled width T (3.543 × 5.906 × 1.772 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 280 kN, C0 400 kN, Pu 46 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3100 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33118U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33118U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33118U designation encode the 90 mm bore and what is 3DE?", "a": "last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 45 mm assembled T follow the ISO 355 dimension-series plan. 3DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33118U list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33118U at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33118U mean?", "a": "Suffix reading on 33118U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33118U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=169", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33118u", "3de", "33118U" ], "locale_variants": {} }, { "sku": "30218U", "brand": "NTN", "manufacturer_designation": "NTN 30218U", "series": "30200-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 160, "B_mm": 32.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 230, "static_load_kN": 267, "fatigue_load_limit_kN": 30.5, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 3000, "weight_g": 2660, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 90 mm bore tapered roller position as 30218U: one cone assembly, one cup, line-contact rollers and a steel cage, rated 230 kN basic dynamic and 267 kN static on the standard-section 30200 family. The last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 32.5 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Suffix reading on 30218U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. The fatigue load limit Pu printed for 30218U is 30.5 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 30218U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2660 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The standard-section 30200 family at 90 mm bore (160×32.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,000 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 30218U at a large fraction of 2,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Never fit the 90 mm cone by hammering the 160 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ISO 355 makes the 90×160 mm envelope interchangeable but not the ratings: NTN prints 230/267 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 230/267 kN ratings and 30.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30218U (ISO 355 3FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30218U?", "a": "30218U is a metric 4T tapered roller bearing to ISO 355: 90 mm bore, 160 mm outside diameter and 32.5 mm assembled width T (3.543 × 6.299 × 1.28 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 230 kN, C0 267 kN, Pu 30.5 kN, grease limiting speed 2,200 r/min, oil speed 3,000 r/min, mass about 2660 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30218U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30218U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30218U designation encode the 90 mm bore and what is 3FB?", "a": "last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table). The 160 mm OD and 32.5 mm assembled T follow the ISO 355 dimension-series plan. 3FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30218U list two speeds, 2,200 and 3,000 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30218U at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30218U mean?", "a": "Suffix reading on 30218U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30218U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30218u", "3fb", "30218U" ], "locale_variants": {} }, { "sku": "32218U", "brand": "NTN", "manufacturer_designation": "NTN 32218U", "series": "32200-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 160, "B_mm": 42.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 291, "static_load_kN": 360, "fatigue_load_limit_kN": 41, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 3000, "weight_g": 3490, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 90 mm bore tapered roller position as 32218U: one cone assembly, one cup, line-contact rollers and a steel cage, rated 291 kN basic dynamic and 360 kN static on the heavy-section 32200 family. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32218U by the metric ISO 355 number (ISO series abbreviation 3FC): 90 mm bore, 160 mm OD. At 291 kN C the bearing offers about 3.2 kN of dynamic capacity per millimetre of the 90 mm bore — compare any substitution on this ratio and the 42.5 mm assembled T, not on bore alone. Selection: C 291 kN against C0 360 kN gives a C0/C ratio of 1.24 for the 90 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Fillet radii must clear the ring chamfers of the 160 mm cup and 90 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3490 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The heavy-section 32200 family at 90 mm bore (160×42.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,000 r/min oil ceiling.", "The 35.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32218U or the ring will bottom out on the radius instead of the shoulder face.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 90 mm shoulder geometry, because retrofitting flips the cups.", "Open 32218U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,200 r/min grease figure is meaningless once water reaches the cone rib.", "The 291/360 kN ratings and 41 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32218U (ISO 355 3FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32218U?", "a": "32218U is a metric 4T tapered roller bearing to ISO 355: 90 mm bore, 160 mm outside diameter and 42.5 mm assembled width T (3.543 × 6.299 × 1.673 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 291 kN, C0 360 kN, Pu 41 kN, grease limiting speed 2,200 r/min, oil speed 3,000 r/min, mass about 3490 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32218U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32218U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32218U designation encode the 90 mm bore and what is 3FC?", "a": "last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table). The 160 mm OD and 42.5 mm assembled T follow the ISO 355 dimension-series plan. 3FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32218U list two speeds, 2,200 and 3,000 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32218U at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32218U mean?", "a": "Suffix reading on 32218U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32218U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32218u", "3fc", "32218U" ], "locale_variants": {} }, { "sku": "33218U", "brand": "NTN", "manufacturer_designation": "NTN 33218U", "series": "33200-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 160, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 360, "static_load_kN": 490, "fatigue_load_limit_kN": 56, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3000, "weight_g": 4620, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 33218U denotes the medium-wide 33200 family of metric tapered roller bearings, 90 mm bore, 160 mm outside diameter and 55 mm assembled width T (3.543 × 6.299 × 2.165 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3FE, which is the maker-neutral cross-reference for the 90×160 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 33218U, not only the raceway. The two speed columns differ by a factor of .77 (grease/limiting 2,300 vs oil 3,000 r/min); heat generation at the cone rib decides which lubrication a real 33218U arrangement can sustain. Mount the 90 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 33218U.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 4620 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The medium-wide 33200 family at 90 mm bore (160×55 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,000 r/min oil ceiling.", "Never fit the 90 mm cone by hammering the 160 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 33218U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,300 r/min grease figure is meaningless once water reaches the cone rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 90 mm shoulder geometry, because retrofitting flips the cups.", "The 360/490 kN ratings and 56 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33218U (ISO 355 3FE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33218U?", "a": "33218U is a metric 4T tapered roller bearing to ISO 355: 90 mm bore, 160 mm outside diameter and 55 mm assembled width T (3.543 × 6.299 × 2.165 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 360 kN, C0 490 kN, Pu 56 kN, grease limiting speed 2,300 r/min, oil speed 3,000 r/min, mass about 4620 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33218U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33218U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33218U designation encode the 90 mm bore and what is 3FE?", "a": "last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table). The 160 mm OD and 55 mm assembled T follow the ISO 355 dimension-series plan. 3FE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33218U list two speeds, 2,300 and 3,000 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33218U at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33218U mean?", "a": "Suffix reading on 33218U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33218U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33218u", "3fe", "33218U" ], "locale_variants": {} }, { "sku": "30318DU", "brand": "NTN", "manufacturer_designation": "NTN 30318DU", "series": "30300-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 190, "B_mm": 46.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 300, "static_load_kN": 320, "fatigue_load_limit_kN": 35.5, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 5580, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 30318DU denotes the large-OD 30300 family with the steeper contact angle of metric tapered roller bearings, 90 mm bore, 190 mm outside diameter and 46.5 mm assembled width T (3.543 × 7.48 × 1.831 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 7GB, which is the maker-neutral cross-reference for the 90×190 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. 2203E lists two speed ceilings for 30318DU: 1,800 r/min with grease lubrication (the limiting speed) and 2,400 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Grease relubrication at 1,800 r/min limiting speed targets the rib contact; if the drive needs 2,400 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Mount the 90 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30318DU.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 5580 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 90 mm bore; do not swap to the lighter family without re-checking the 1,800 r/min grease limit and the thrust load split.", "Never fit the 90 mm cone by hammering the 190 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ISO 355 makes the 90×190 mm envelope interchangeable but not the ratings: NTN prints 300/320 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Grease packs must leave free volume in the 46.5 mm-wide set; over-greasing a paired bearing churning at the 2,400 r/min oil-band speed raises temperature and destroys the preload setting.", "The 300/320 kN ratings and 35.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30318DU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30318DU?", "a": "30318DU is a metric 4T tapered roller bearing to ISO 355: 90 mm bore, 190 mm outside diameter and 46.5 mm assembled width T (3.543 × 7.48 × 1.831 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 300 kN, C0 320 kN, Pu 35.5 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 5580 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30318DU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30318DU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30318DU designation encode the 90 mm bore and what is 7GB?", "a": "last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table). The 190 mm OD and 46.5 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30318DU list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30318DU at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30318DU mean?", "a": "Suffix reading on 30318DU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30318DU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30318du", "7gb", "30318DU" ], "locale_variants": {} }, { "sku": "30318U", "brand": "NTN", "manufacturer_designation": "NTN 30318U", "series": "30300-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 190, "B_mm": 46.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 375, "static_load_kN": 405, "fatigue_load_limit_kN": 44.5, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2700, "weight_g": 5830, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30318U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 90×190 mm ISO 355 envelope, with 46.5 mm overall assembled width T. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30318U resolves to 90 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Individually mounted, 30318U takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Grease relubrication at 2,000 r/min limiting speed targets the rib contact; if the drive needs 2,700 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 30318U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 5830 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 90 mm bore; do not swap to the lighter family without re-checking the 2,000 r/min grease limit and the thrust load split.", "Grease packs must leave free volume in the 46.5 mm-wide set; over-greasing a paired bearing churning at the 2,700 r/min oil-band speed raises temperature and destroys the preload setting.", "Grease packs must leave free volume in the 46.5 mm-wide set; over-greasing a paired bearing churning at the 2,700 r/min oil-band speed raises temperature and destroys the preload setting.", "Never fit the 90 mm cone by hammering the 190 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 375/405 kN ratings and 44.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30318U (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30318U?", "a": "30318U is a metric 4T tapered roller bearing to ISO 355: 90 mm bore, 190 mm outside diameter and 46.5 mm assembled width T (3.543 × 7.48 × 1.831 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 375 kN, C0 405 kN, Pu 44.5 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 5830 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30318U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30318U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30318U designation encode the 90 mm bore and what is 2GB?", "a": "last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table). The 190 mm OD and 46.5 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30318U list two speeds, 2,000 and 2,700 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30318U at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30318U mean?", "a": "Suffix reading on 30318U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30318U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30318u", "30318U" ], "locale_variants": {} }, { "sku": "32318U", "brand": "NTN", "manufacturer_designation": "NTN 32318U", "series": "32300-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 190, "B_mm": 67.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 500, "static_load_kN": 595, "fatigue_load_limit_kN": 65.5, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2700, "weight_g": 8660, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32318U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 90×190 mm ISO 355 envelope, with 67.5 mm overall assembled width T. Digit by digit, the bare number identifies the extra-heavy 32300 family and a bore code resolving to 90 mm; 190 mm OD and 67.5 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32318U, since running clearance is set during assembly. Catalogue mass of the 32318U set is 8660 g (0.341 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Fillet radii must clear the ring chamfers of the 190 mm cup and 90 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 8660 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 90 mm bore (190×67.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,700 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 32318U at a large fraction of 2,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Open 32318U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,000 r/min grease figure is meaningless once water reaches the cone rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 90 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 500/595 kN ratings and 65.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32318U (ISO 355 2GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32318U?", "a": "32318U is a metric 4T tapered roller bearing to ISO 355: 90 mm bore, 190 mm outside diameter and 67.5 mm assembled width T (3.543 × 7.48 × 2.657 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 500 kN, C0 595 kN, Pu 65.5 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 8660 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32318U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32318U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32318U designation encode the 90 mm bore and what is 2GD?", "a": "last two digits 18 are the ISO bore code, ×5 = 90 mm (codes 00–03 use the 10/12/15/17 exception table). The 190 mm OD and 67.5 mm assembled T follow the ISO 355 dimension-series plan. 2GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32318U list two speeds, 2,000 and 2,700 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32318U at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32318U mean?", "a": "Suffix reading on 32318U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32318U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gd", "32318u", "32318U" ], "locale_variants": {} }, { "sku": "32919XU", "brand": "NTN", "manufacturer_designation": "NTN 32919XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 130, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 112, "static_load_kN": 178, "fatigue_load_limit_kN": 21, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3400, "weight_g": 851, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32919XU is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 95×130 mm ISO 355 envelope, with 23 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32919XU by the metric ISO 355 number (ISO series abbreviation 2BC): 95 mm bore, 130 mm OD. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32919XU, not only the raceway. Grease relubrication at 2,500 r/min limiting speed targets the rib contact; if the drive needs 3,400 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32919XU arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 95 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 851 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 23 mm section of 32919XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 95 mm bore smears the roller ends against the rib.", "ISO 355 makes the 95×130 mm envelope interchangeable but not the ratings: NTN prints 112/178 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32919XU by size alone can deliver the wrong contact-angle execution for a pinion position.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 95 mm shoulder geometry, because retrofitting flips the cups.", "The 112/178 kN ratings and 21 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32919XU (ISO 355 2BC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32919XU?", "a": "32919XU is a metric 4T tapered roller bearing to ISO 355: 95 mm bore, 130 mm outside diameter and 23 mm assembled width T (3.74 × 5.118 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 112 kN, C0 178 kN, Pu 21 kN, grease limiting speed 2,500 r/min, oil speed 3,400 r/min, mass about 851 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32919XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32919XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32919XU designation encode the 95 mm bore and what is 2BC?", "a": "last two digits 19 are the ISO bore code, ×5 = 95 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 23 mm assembled T follow the ISO 355 dimension-series plan. 2BC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32919XU list two speeds, 2,500 and 3,400 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32919XU at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32919XU mean?", "a": "Suffix reading on 32919XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32919XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2bc", "32919xu", "32919XU" ], "locale_variants": {} }, { "sku": "32019XU", "brand": "NTN", "manufacturer_designation": "NTN 32019XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 145, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 190, "static_load_kN": 280, "fatigue_load_limit_kN": 32.5, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 1850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32019XU in the low-section 32000 family tuned for low friction: 95 mm bore, 145 mm cup OD, 32 mm T, with a grease limiting speed of 2,300 r/min and an oil-lubricated ceiling of 3,100 r/min. Digit by digit, the bare number identifies the low-section 32000 family tuned for low friction and a bore code resolving to 95 mm; 145 mm OD and 32 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The 25.0 mm radial section carries the roller complement across the 95–145 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Speed planning uses both catalogue columns: grease 2,300 r/min is the cage/rib mechanical ceiling for 32019XU, oil 3,100 r/min is available with circulating oil — a 800 r/min margin at this size. Fillet radii must clear the ring chamfers of the 145 mm cup and 95 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 95 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1850 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 32 mm section of 32019XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 95 mm bore smears the roller ends against the rib.", "ISO 355 makes the 95×145 mm envelope interchangeable but not the ratings: NTN prints 190/280 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "ISO 355 makes the 95×145 mm envelope interchangeable but not the ratings: NTN prints 190/280 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32019XU by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 190/280 kN ratings and 32.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32019XU (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32019XU?", "a": "32019XU is a metric 4T tapered roller bearing to ISO 355: 95 mm bore, 145 mm outside diameter and 32 mm assembled width T (3.74 × 5.709 × 1.26 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 190 kN, C0 280 kN, Pu 32.5 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 1850 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32019XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32019XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32019XU designation encode the 95 mm bore and what is 4CC?", "a": "last two digits 19 are the ISO bore code, ×5 = 95 mm (codes 00–03 use the 10/12/15/17 exception table). The 145 mm OD and 32 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32019XU list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32019XU at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32019XU mean?", "a": "Suffix reading on 32019XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32019XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32019xu", "4cc", "32019XU" ], "locale_variants": {} }, { "sku": "33019U", "brand": "NTN", "manufacturer_designation": "NTN 33019U", "series": "33000-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 145, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 243, "static_load_kN": 375, "fatigue_load_limit_kN": 43, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 2300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 33019U denotes the slim 33000 family of metric tapered roller bearings, 95 mm bore, 145 mm outside diameter and 39 mm assembled width T (3.74 × 5.709 × 1.535 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the slim 33000 family and a bore code resolving to 95 mm; 145 mm OD and 39 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. 2203E lists two speed ceilings for 33019U: 2,300 r/min with grease lubrication (the limiting speed) and 3,100 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. The 25.0 mm section height over the 95 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 95 mm pair is misadjusted and the 39 mm T set will edge-load in service.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 95 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2300 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 39 mm section of 33019U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 95 mm bore smears the roller ends against the rib.", "The 25.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33019U or the ring will bottom out on the radius instead of the shoulder face.", "The 25.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33019U or the ring will bottom out on the radius instead of the shoulder face.", "Grease packs must leave free volume in the 39 mm-wide set; over-greasing a paired bearing churning at the 3,100 r/min oil-band speed raises temperature and destroys the preload setting.", "The 243/375 kN ratings and 43 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33019U (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33019U?", "a": "33019U is a metric 4T tapered roller bearing to ISO 355: 95 mm bore, 145 mm outside diameter and 39 mm assembled width T (3.74 × 5.709 × 1.535 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 243 kN, C0 375 kN, Pu 43 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 2300 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33019U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33019U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33019U designation encode the 95 mm bore and what is 2CE?", "a": "last two digits 19 are the ISO bore code, ×5 = 95 mm (codes 00–03 use the 10/12/15/17 exception table). The 145 mm OD and 39 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33019U list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33019U at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33019U mean?", "a": "Suffix reading on 33019U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33019U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "33019u", "33019U" ], "locale_variants": {} }, { "sku": "30219U", "brand": "NTN", "manufacturer_designation": "NTN 30219U", "series": "30200-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 170, "B_mm": 34.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 250, "static_load_kN": 290, "fatigue_load_limit_kN": 32.5, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 3120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 95 mm shaft with a thrust component, NTN lists 30219U, a metric 4T tapered roller bearing of 250 kN C and 290 kN C0 inside the 170 mm OD, 34.5 mm-wide assembled set. Digit by digit, the bare number identifies the standard-section 30200 family and a bore code resolving to 95 mm; 170 mm OD and 34.5 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN grades 4T metric bearings as open bearings without integral seals; at 95 mm bore the application supplies the seals and the grease fill or oil supply to the 3FB ISO 355 assembly. Catalogue mass of the 30219U set is 3120 g (0.123 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 95 mm pair is misadjusted and the 34.5 mm T set will edge-load in service.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 95 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3120 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The standard-section 30200 family at 95 mm bore (170×34.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,800 r/min oil ceiling.", "Do not confuse T (34.5 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 95 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 37.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30219U or the ring will bottom out on the radius instead of the shoulder face.", "The 250/290 kN ratings and 32.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30219U (ISO 355 3FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30219U?", "a": "30219U is a metric 4T tapered roller bearing to ISO 355: 95 mm bore, 170 mm outside diameter and 34.5 mm assembled width T (3.74 × 6.693 × 1.358 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 250 kN, C0 290 kN, Pu 32.5 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 3120 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30219U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30219U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30219U designation encode the 95 mm bore and what is 3FB?", "a": "last two digits 19 are the ISO bore code, ×5 = 95 mm (codes 00–03 use the 10/12/15/17 exception table). The 170 mm OD and 34.5 mm assembled T follow the ISO 355 dimension-series plan. 3FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30219U list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30219U at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30219U mean?", "a": "Suffix reading on 30219U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30219U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30219u", "3fb", "30219U" ], "locale_variants": {} }, { "sku": "32219U", "brand": "NTN", "manufacturer_designation": "NTN 32219U", "series": "32200-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 170, "B_mm": 45.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 330, "static_load_kN": 415, "fatigue_load_limit_kN": 47, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 4290, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 95 mm shaft with a thrust component, NTN lists 32219U, a metric 4T tapered roller bearing of 330 kN C and 415 kN C0 inside the 170 mm OD, 45.5 mm-wide assembled set. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3FC, which is the maker-neutral cross-reference for the 95×170 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32219U, not only the raceway. Speed planning uses both catalogue columns: grease 2,100 r/min is the cage/rib mechanical ceiling for 32219U, oil 2,800 r/min is available with circulating oil — a 700 r/min margin at this size. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32219U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 95 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 4290 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The heavy-section 32200 family at 95 mm bore (170×45.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,800 r/min oil ceiling.", "ISO 355 makes the 95×170 mm envelope interchangeable but not the ratings: NTN prints 330/415 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Do not confuse T (45.5 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 95 mm shoulder geometry, because retrofitting flips the cups.", "The 330/415 kN ratings and 47 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32219U (ISO 355 3FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32219U?", "a": "32219U is a metric 4T tapered roller bearing to ISO 355: 95 mm bore, 170 mm outside diameter and 45.5 mm assembled width T (3.74 × 6.693 × 1.791 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 330 kN, C0 415 kN, Pu 47 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 4290 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32219U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32219U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32219U designation encode the 95 mm bore and what is 3FC?", "a": "last two digits 19 are the ISO bore code, ×5 = 95 mm (codes 00–03 use the 10/12/15/17 exception table). The 170 mm OD and 45.5 mm assembled T follow the ISO 355 dimension-series plan. 3FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32219U list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32219U at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32219U mean?", "a": "Suffix reading on 32219U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32219U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32219u", "3fc", "32219U" ], "locale_variants": {} }, { "sku": "30319DU", "brand": "NTN", "manufacturer_designation": "NTN 30319DU", "series": "30300-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 200, "B_mm": 49.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 330, "static_load_kN": 355, "fatigue_load_limit_kN": 38.5, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 6350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30319DU is the NTN 4T catalogue entry for a 95×200×49.5 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. The last two digits 19 are the ISO bore code, ×5 = 95 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 49.5 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The printed contact-angle geometry gives the large-OD 30300 family with the steeper contact angle its characteristic load split — at 330/355 kN (C/C0) the static rating is about 1.08× C, typical of tapered bearings proportioned for heavy combined duty. Selection: C 330 kN against C0 355 kN gives a C0/C ratio of 1.08 for the 95 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Mount the 95 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30319DU.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 95 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 6350 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 95 mm bore; do not swap to the lighter family without re-checking the 1,700 r/min grease limit and the thrust load split.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 95 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Do not confuse T (49.5 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Minimum load matters at high speed: an unloaded 30319DU at a large fraction of 1,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 330/355 kN ratings and 38.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30319DU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30319DU?", "a": "30319DU is a metric 4T tapered roller bearing to ISO 355: 95 mm bore, 200 mm outside diameter and 49.5 mm assembled width T (3.74 × 7.874 × 1.949 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 330 kN, C0 355 kN, Pu 38.5 kN, grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 6350 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30319DU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30319DU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30319DU designation encode the 95 mm bore and what is 7GB?", "a": "last two digits 19 are the ISO bore code, ×5 = 95 mm (codes 00–03 use the 10/12/15/17 exception table). The 200 mm OD and 49.5 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30319DU list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30319DU at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30319DU mean?", "a": "Suffix reading on 30319DU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30319DU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30319du", "7gb", "30319DU" ], "locale_variants": {} }, { "sku": "30319U", "brand": "NTN", "manufacturer_designation": "NTN 30319U", "series": "30300-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 200, "B_mm": 49.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 405, "static_load_kN": 445, "fatigue_load_limit_kN": 48.5, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2500, "weight_g": 6690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30319U is the NTN 4T catalogue entry for a 95×200×49.5 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. The last two digits 19 are the ISO bore code, ×5 = 95 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 49.5 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Suffix reading on 30319U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. The 4.3 kN-per-mm-bore capacity figure for 30319U summarises the 405 kN rating over 95 mm bore; use it to sanity-check an interchange candidate before swapping brands. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 95 mm pair is misadjusted and the 49.5 mm T set will edge-load in service.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 95 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 6690 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 95 mm bore; do not swap to the lighter family without re-checking the 1,900 r/min grease limit and the thrust load split.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 95 mm shoulder geometry, because retrofitting flips the cups.", "Minimum load matters at high speed: an unloaded 30319U at a large fraction of 1,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "ISO 355 makes the 95×200 mm envelope interchangeable but not the ratings: NTN prints 405/445 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 405/445 kN ratings and 48.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30319U (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30319U?", "a": "30319U is a metric 4T tapered roller bearing to ISO 355: 95 mm bore, 200 mm outside diameter and 49.5 mm assembled width T (3.74 × 7.874 × 1.949 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 405 kN, C0 445 kN, Pu 48.5 kN, grease limiting speed 1,900 r/min, oil speed 2,500 r/min, mass about 6690 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30319U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30319U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30319U designation encode the 95 mm bore and what is 2GB?", "a": "last two digits 19 are the ISO bore code, ×5 = 95 mm (codes 00–03 use the 10/12/15/17 exception table). The 200 mm OD and 49.5 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30319U list two speeds, 1,900 and 2,500 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30319U at 2,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30319U mean?", "a": "Suffix reading on 30319U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30319U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30319u", "30319U" ], "locale_variants": {} }, { "sku": "32319U", "brand": "NTN", "manufacturer_designation": "NTN 32319U", "series": "32300-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 200, "B_mm": 71.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 560, "static_load_kN": 670, "fatigue_load_limit_kN": 73, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2500, "weight_g": 10100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32319U is the NTN 4T catalogue entry for a 95×200×71.5 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32319U by the metric ISO 355 number (ISO series abbreviation 2GD): 95 mm bore, 200 mm OD. 2203E lists two speed ceilings for 32319U: 1,900 r/min with grease lubrication (the limiting speed) and 2,500 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Catalogue mass of the 32319U set is 10100 g (0.398 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Open 4T bearings need application seals; without them the grease at the cone rib of 32319U washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 95 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 10100 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 95 mm bore (200×71.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,500 r/min oil ceiling.", "Do not confuse T (71.5 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Open 32319U units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,900 r/min grease figure is meaningless once water reaches the cone rib.", "Grease packs must leave free volume in the 71.5 mm-wide set; over-greasing a paired bearing churning at the 2,500 r/min oil-band speed raises temperature and destroys the preload setting.", "The 560/670 kN ratings and 73 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32319U (ISO 355 2GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32319U?", "a": "32319U is a metric 4T tapered roller bearing to ISO 355: 95 mm bore, 200 mm outside diameter and 71.5 mm assembled width T (3.74 × 7.874 × 2.815 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 560 kN, C0 670 kN, Pu 73 kN, grease limiting speed 1,900 r/min, oil speed 2,500 r/min, mass about 10100 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32319U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32319U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32319U designation encode the 95 mm bore and what is 2GD?", "a": "last two digits 19 are the ISO bore code, ×5 = 95 mm (codes 00–03 use the 10/12/15/17 exception table). The 200 mm OD and 71.5 mm assembled T follow the ISO 355 dimension-series plan. 2GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32319U list two speeds, 1,900 and 2,500 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32319U at 2,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32319U mean?", "a": "Suffix reading on 32319U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32319U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gd", "32319u", "32319U" ], "locale_variants": {} }, { "sku": "32920-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32920", "series": "32900-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 140, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 108, "static_load_kN": 162, "fatigue_load_limit_kN": 18.6, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 1080, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32920 is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 100×140 mm ISO 355 envelope, with 25 mm overall assembled width T. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 100 mm; 140 mm OD and 25 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. With no letter after the number, 32920 is the basic open 4T execution: steel cage, normal adjustment, no seal or special internal-design suffix in the order code. The two speed columns differ by a factor of .75 (grease/limiting 2,400 vs oil 3,200 r/min); heat generation at the cone rib decides which lubrication a real 32920 arrangement can sustain. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 100 mm pair is misadjusted and the 25 mm T set will edge-load in service.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1080 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 25 mm section of 32920 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 100 mm bore smears the roller ends against the rib.", "Do not confuse T (25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32920 by size alone can deliver the wrong contact-angle execution for a pinion position.", "ISO 355 makes the 100×140 mm envelope interchangeable but not the ratings: NTN prints 108/162 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 108/162 kN ratings and 18.6 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32920; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32920?", "a": "32920 is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 140 mm outside diameter and 25 mm assembled width T (3.937 × 5.512 × 0.984 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 108 kN, C0 162 kN, Pu 18.6 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 1080 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32920?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32920); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32920 designation encode the 100 mm bore?", "a": "last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table). The 140 mm OD and 25 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32920 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32920 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32920 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32920", "equiv_brand": "SKF", "level": "partial", "note": "Same 100×140×25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "32920-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "○32920", "32920", "32920-NTN" ], "locale_variants": {} }, { "sku": "32920XU", "brand": "NTN", "manufacturer_designation": "NTN 32920XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 140, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 134, "static_load_kN": 206, "fatigue_load_limit_kN": 23.8, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 1120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32920XU belongs to the NTN metric 4T tapered roller range (extra-light thin-section 32900 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. The last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 25 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32920XU, not only the raceway. Imperial cross-check for the drawing: 100×140×25 mm is 3.937 × 5.512 × 0.984 in; ISO 355 makes the envelope interchangeable but C/C0, 134/206 kN, is NTN-specific. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32920XU arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1120 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 25 mm section of 32920XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 100 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 100 mm shoulder geometry, because retrofitting flips the cups.", "The 134/206 kN ratings and 23.8 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32920XU (ISO 355 2CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32920XU?", "a": "32920XU is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 140 mm outside diameter and 25 mm assembled width T (3.937 × 5.512 × 0.984 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 134 kN, C0 206 kN, Pu 23.8 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 1120 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32920XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32920XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32920XU designation encode the 100 mm bore and what is 2CC?", "a": "last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table). The 140 mm OD and 25 mm assembled T follow the ISO 355 dimension-series plan. 2CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32920XU list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32920XU at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32920XU mean?", "a": "Suffix reading on 32920XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32920XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2cc", "32920xu", "32920XU" ], "locale_variants": {} }, { "sku": "T4CB100", "brand": "NTN", "manufacturer_designation": "NTN T4CB100", "series": "T4CB-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 145, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 119, "static_load_kN": 153, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 1140, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "T4CB100 is the NTN 4T catalogue entry for a 100×145×24 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and T4CB100 resolves to 100 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. 2203E lists two speed ceilings for T4CB100: 1,800 r/min with grease lubrication (the limiting speed) and 2,400 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. The two speed columns differ by a factor of .75 (grease/limiting 1,800 vs oil 2,400 r/min); heat generation at the cone rib decides which lubrication a real T4CB100 arrangement can sustain. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 100 mm pair is misadjusted and the 24 mm T set will edge-load in service.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1140 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The large-size ISO 355 tapered-roller family at 100 mm bore (145×24 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,400 r/min oil ceiling.", "Open T4CB100 units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,800 r/min grease figure is meaningless once water reaches the cone rib.", "ISO 355 makes the 100×145 mm envelope interchangeable but not the ratings: NTN prints 119/153 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Grease packs must leave free volume in the 24 mm-wide set; over-greasing a paired bearing churning at the 2,400 r/min oil-band speed raises temperature and destroys the preload setting.", "The 119/153 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T4CB100 (ISO 355 4CB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T4CB100?", "a": "T4CB100 is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 145 mm outside diameter and 24 mm assembled width T (3.937 × 5.709 × 0.945 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 119 kN, C0 153 kN (2203E prints no Pu for this size), grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 1140 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T4CB100?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T4CB100); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T4CB100 designation encode the 100 mm bore and what is 4CB?", "a": "trailing dimension block 100 prints the 100 mm bore directly for this large-size T-code. The 145 mm OD and 24 mm assembled T follow the ISO 355 dimension-series plan. 4CB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T4CB100 list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T4CB100 at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T4CB100 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 100 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T4CB100", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4cb", "4t-t4cb100", "t4cb100", "T4CB100" ], "locale_variants": {} }, { "sku": "32020XU", "brand": "NTN", "manufacturer_designation": "NTN 32020XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 150, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 188, "static_load_kN": 281, "fatigue_load_limit_kN": 32, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 3000, "weight_g": 1910, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 100 mm shaft with a thrust component, NTN lists 32020XU, a metric 4T tapered roller bearing of 188 kN C and 281 kN C0 inside the 150 mm OD, 32 mm-wide assembled set. The last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 32 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. At 188 kN C the bearing offers about 1.9 kN of dynamic capacity per millimetre of the 100 mm bore — compare any substitution on this ratio and the 32 mm assembled T, not on bore alone. Grease relubrication at 2,200 r/min limiting speed targets the rib contact; if the drive needs 3,000 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 32020XU; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1910 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 32 mm section of 32020XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 100 mm bore smears the roller ends against the rib.", "The 25.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32020XU or the ring will bottom out on the radius instead of the shoulder face.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32020XU by size alone can deliver the wrong contact-angle execution for a pinion position.", "Open 32020XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,200 r/min grease figure is meaningless once water reaches the cone rib.", "The 188/281 kN ratings and 32 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32020XU (ISO 355 4CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32020XU?", "a": "32020XU is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 150 mm outside diameter and 32 mm assembled width T (3.937 × 5.906 × 1.26 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 188 kN, C0 281 kN, Pu 32 kN, grease limiting speed 2,200 r/min, oil speed 3,000 r/min, mass about 1910 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32020XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32020XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32020XU designation encode the 100 mm bore and what is 4CC?", "a": "last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 32 mm assembled T follow the ISO 355 dimension-series plan. 4CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32020XU list two speeds, 2,200 and 3,000 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32020XU at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32020XU mean?", "a": "Suffix reading on 32020XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32020XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32020xu", "4cc", "32020XU" ], "locale_variants": {} }, { "sku": "33020U", "brand": "NTN", "manufacturer_designation": "NTN 33020U", "series": "33000-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 150, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 248, "static_load_kN": 390, "fatigue_load_limit_kN": 44.5, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 3000, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 33020U in the slim 33000 family: 100 mm bore, 150 mm cup OD, 39 mm T, with a grease limiting speed of 2,200 r/min and an oil-lubricated ceiling of 3,000 r/min. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 33020U resolves to 100 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. At 248 kN C the bearing offers about 2.5 kN of dynamic capacity per millimetre of the 100 mm bore — compare any substitution on this ratio and the 39 mm assembled T, not on bore alone. The two speed columns differ by a factor of .73 (grease/limiting 2,200 vs oil 3,000 r/min); heat generation at the cone rib decides which lubrication a real 33020U arrangement can sustain. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 33020U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2400 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 39 mm section of 33020U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 100 mm bore smears the roller ends against the rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 100 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 100 mm shoulder geometry, because retrofitting flips the cups.", "Open 33020U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,200 r/min grease figure is meaningless once water reaches the cone rib.", "The 248/390 kN ratings and 44.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33020U (ISO 355 2CE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33020U?", "a": "33020U is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 150 mm outside diameter and 39 mm assembled width T (3.937 × 5.906 × 1.535 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 248 kN, C0 390 kN, Pu 44.5 kN, grease limiting speed 2,200 r/min, oil speed 3,000 r/min, mass about 2400 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33020U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33020U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33020U designation encode the 100 mm bore and what is 2CE?", "a": "last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 39 mm assembled T follow the ISO 355 dimension-series plan. 2CE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33020U list two speeds, 2,200 and 3,000 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33020U at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33020U mean?", "a": "Suffix reading on 33020U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33020U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2ce", "33020u", "33020U" ], "locale_variants": {} }, { "sku": "30220U", "brand": "NTN", "manufacturer_designation": "NTN 30220U", "series": "30200-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 180, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 286, "static_load_kN": 335, "fatigue_load_limit_kN": 37, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2700, "weight_g": 3760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 30220U denotes the standard-section 30200 family of metric tapered roller bearings, 100 mm bore, 180 mm outside diameter and 37 mm assembled width T (3.937 × 7.087 × 1.457 in) to the ISO 355 boundary plan. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30220U resolves to 100 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Individually mounted, 30220U takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Imperial cross-check for the drawing: 100×180×37 mm is 3.937 × 7.087 × 1.457 in; ISO 355 makes the envelope interchangeable but C/C0, 286/335 kN, is NTN-specific. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 30220U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3760 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The standard-section 30200 family at 100 mm bore (180×37 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,700 r/min oil ceiling.", "Grease packs must leave free volume in the 37 mm-wide set; over-greasing a paired bearing churning at the 2,700 r/min oil-band speed raises temperature and destroys the preload setting.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30220U by size alone can deliver the wrong contact-angle execution for a pinion position.", "Never fit the 100 mm cone by hammering the 180 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 286/335 kN ratings and 37 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30220U (ISO 355 3FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30220U?", "a": "30220U is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 180 mm outside diameter and 37 mm assembled width T (3.937 × 7.087 × 1.457 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 286 kN, C0 335 kN, Pu 37 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 3760 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30220U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30220U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30220U designation encode the 100 mm bore and what is 3FB?", "a": "last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 37 mm assembled T follow the ISO 355 dimension-series plan. 3FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30220U list two speeds, 2,000 and 2,700 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30220U at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30220U mean?", "a": "Suffix reading on 30220U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30220U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30220u", "3fb", "30220U" ], "locale_variants": {} }, { "sku": "32220U", "brand": "NTN", "manufacturer_designation": "NTN 32220U", "series": "32200-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 180, "B_mm": 49, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 365, "static_load_kN": 465, "fatigue_load_limit_kN": 51, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2700, "weight_g": 5110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32220U denotes the heavy-section 32200 family of metric tapered roller bearings, 100 mm bore, 180 mm outside diameter and 49 mm assembled width T (3.937 × 7.087 × 1.929 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the heavy-section 32200 family and a bore code resolving to 100 mm; 180 mm OD and 49 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32220U, since running clearance is set during assembly. Grease relubrication at 2,000 r/min limiting speed targets the rib contact; if the drive needs 2,700 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. When pairing 32220U with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 5110 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The heavy-section 32200 family at 100 mm bore (180×49 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,700 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 32220U at a large fraction of 2,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "ISO 355 makes the 100×180 mm envelope interchangeable but not the ratings: NTN prints 365/465 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 100 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 365/465 kN ratings and 51 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32220U (ISO 355 3FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32220U?", "a": "32220U is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 180 mm outside diameter and 49 mm assembled width T (3.937 × 7.087 × 1.929 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 365 kN, C0 465 kN, Pu 51 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 5110 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32220U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32220U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32220U designation encode the 100 mm bore and what is 3FC?", "a": "last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 49 mm assembled T follow the ISO 355 dimension-series plan. 3FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32220U list two speeds, 2,000 and 2,700 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32220U at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32220U mean?", "a": "Suffix reading on 32220U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32220U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32220u", "3fc", "32220U" ], "locale_variants": {} }, { "sku": "33220U", "brand": "NTN", "manufacturer_designation": "NTN 33220U", "series": "33200-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 180, "B_mm": 63, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 465, "static_load_kN": 650, "fatigue_load_limit_kN": 71.5, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2700, "weight_g": 6760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33220U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 100×180 mm ISO 355 envelope, with 63 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 33220U by the metric ISO 355 number (ISO series abbreviation 3FE): 100 mm bore, 180 mm OD. At 465 kN C the bearing offers about 4.7 kN of dynamic capacity per millimetre of the 100 mm bore — compare any substitution on this ratio and the 63 mm assembled T, not on bore alone. The 40.0 mm section height over the 100 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Open 4T bearings need application seals; without them the grease at the cone rib of 33220U washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 6760 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The medium-wide 33200 family at 100 mm bore (180×63 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,700 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 63 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never fit the 100 mm cone by hammering the 180 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 33220U units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,000 r/min grease figure is meaningless once water reaches the cone rib.", "The 465/650 kN ratings and 71.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33220U (ISO 355 3FE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33220U?", "a": "33220U is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 180 mm outside diameter and 63 mm assembled width T (3.937 × 7.087 × 2.48 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 465 kN, C0 650 kN, Pu 71.5 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 6760 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33220U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33220U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33220U designation encode the 100 mm bore and what is 3FE?", "a": "last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 63 mm assembled T follow the ISO 355 dimension-series plan. 3FE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33220U list two speeds, 2,000 and 2,700 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33220U at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33220U mean?", "a": "Suffix reading on 33220U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33220U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33220u", "3fe", "33220U" ], "locale_variants": {} }, { "sku": "30320U", "brand": "NTN", "manufacturer_designation": "NTN 30320U", "series": "30300-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 215, "B_mm": 51.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 455, "static_load_kN": 500, "fatigue_load_limit_kN": 53, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 8300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30320U belongs to the NTN metric 4T tapered roller range (large-OD 30300 family with the steeper contact angle); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2GB, which is the maker-neutral cross-reference for the 100×215 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. Suffix reading on 30320U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. Selection: C 455 kN against C0 500 kN gives a C0/C ratio of 1.10 for the 100 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 30320U washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 8300 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 100 mm bore; do not swap to the lighter family without re-checking the 1,800 r/min grease limit and the thrust load split.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30320U by size alone can deliver the wrong contact-angle execution for a pinion position.", "Minimum load matters at high speed: an unloaded 30320U at a large fraction of 1,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "ISO 355 makes the 100×215 mm envelope interchangeable but not the ratings: NTN prints 455/500 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 455/500 kN ratings and 53 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30320U (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30320U?", "a": "30320U is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 215 mm outside diameter and 51.5 mm assembled width T (3.937 × 8.465 × 2.028 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 455 kN, C0 500 kN, Pu 53 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 8300 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30320U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30320U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30320U designation encode the 100 mm bore and what is 2GB?", "a": "last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table). The 215 mm OD and 51.5 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30320U list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30320U at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30320U mean?", "a": "Suffix reading on 30320U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30320U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30320u", "30320U" ], "locale_variants": {} }, { "sku": "31320XU", "brand": "NTN", "manufacturer_designation": "NTN 31320XU", "series": "31300-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 215, "B_mm": 56.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 395, "static_load_kN": 435, "fatigue_load_limit_kN": 46, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 8700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "31320XU belongs to the NTN metric 4T tapered roller range (steep-angle 31300 family for high axial load share); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Digit by digit, the bare number identifies the steep-angle 31300 family for high axial load share and a bore code resolving to 100 mm; 215 mm OD and 56.5 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 31320XU, since running clearance is set during assembly. The 57.5 mm section height over the 100 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 31320XU; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 8700 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the steep-angle 31300 family for high axial load share raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 100 mm bore; do not swap to the lighter family without re-checking the 1,800 r/min grease limit and the thrust load split.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 31320XU by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 57.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 31320XU or the ring will bottom out on the radius instead of the shoulder face.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 100 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 395/435 kN ratings and 46 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 31320XU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 31320XU?", "a": "31320XU is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 215 mm outside diameter and 56.5 mm assembled width T (3.937 × 8.465 × 2.224 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 395 kN, C0 435 kN, Pu 46 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 8700 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 31320XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (31320XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 31320XU designation encode the 100 mm bore and what is 7GB?", "a": "last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table). The 215 mm OD and 56.5 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 31320XU list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 31320XU at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 31320XU mean?", "a": "Suffix reading on 31320XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "31320XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "31320xu", "7gb", "31320XU" ], "locale_variants": {} }, { "sku": "32320U", "brand": "NTN", "manufacturer_designation": "NTN 32320U", "series": "32300-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 215, "B_mm": 77.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 635, "static_load_kN": 770, "fatigue_load_limit_kN": 82, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 12800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32320U belongs to the NTN metric 4T tapered roller range (extra-heavy 32300 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. The last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 77.5 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. At 635 kN C the bearing offers about 6.3 kN of dynamic capacity per millimetre of the 100 mm bore — compare any substitution on this ratio and the 77.5 mm assembled T, not on bore alone. Imperial cross-check for the drawing: 100×215×77.5 mm is 3.937 × 8.465 × 3.051 in; ISO 355 makes the envelope interchangeable but C/C0, 635/770 kN, is NTN-specific. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 32320U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 12800 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 100 mm bore (215×77.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,400 r/min oil ceiling.", "Grease packs must leave free volume in the 77.5 mm-wide set; over-greasing a paired bearing churning at the 2,400 r/min oil-band speed raises temperature and destroys the preload setting.", "Replacing one half of an adjusted pair without resetting end play negates the 77.5 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 32320U units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,800 r/min grease figure is meaningless once water reaches the cone rib.", "The 635/770 kN ratings and 82 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32320U (ISO 355 2GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32320U?", "a": "32320U is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 215 mm outside diameter and 77.5 mm assembled width T (3.937 × 8.465 × 3.051 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 635 kN, C0 770 kN, Pu 82 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 12800 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32320U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32320U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32320U designation encode the 100 mm bore and what is 2GD?", "a": "last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table). The 215 mm OD and 77.5 mm assembled T follow the ISO 355 dimension-series plan. 2GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32320U list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32320U at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32320U mean?", "a": "Suffix reading on 32320U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32320U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gd", "32320u", "32320U" ], "locale_variants": {} }, { "sku": "32921XA", "brand": "NTN", "manufacturer_designation": "NTN 32921XA", "series": "32900-series", "type": "tapered_roller", "d_mm": 105, "D_mm": 145, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 139, "static_load_kN": 219, "fatigue_load_limit_kN": 25, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3000, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 105 mm bore tapered roller position as 32921XA: one cone assembly, one cup, line-contact rollers and a steel cage, rated 139 kN basic dynamic and 219 kN static on the extra-light thin-section 32900 family. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32921XA by the metric ISO 355 number: 105 mm bore, 145 mm OD. At 139 kN C the bearing offers about 1.3 kN of dynamic capacity per millimetre of the 105 mm bore — compare any substitution on this ratio and the 25 mm assembled T, not on bore alone. Grease relubrication at 2,300 r/min limiting speed targets the rib contact; if the drive needs 3,000 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 105 mm pair is misadjusted and the 25 mm T set will edge-load in service.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 105 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1200 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 25 mm section of 32921XA is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 105 mm bore smears the roller ends against the rib.", "Do not confuse T (25 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Grease packs must leave free volume in the 25 mm-wide set; over-greasing a paired bearing churning at the 3,000 r/min oil-band speed raises temperature and destroys the preload setting.", "Open 32921XA units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,300 r/min grease figure is meaningless once water reaches the cone rib.", "The 139/219 kN ratings and 25 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32921XA; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32921XA?", "a": "32921XA is a metric 4T tapered roller bearing to ISO 355: 105 mm bore, 145 mm outside diameter and 25 mm assembled width T (4.134 × 5.709 × 0.984 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 139 kN, C0 219 kN, Pu 25 kN, grease limiting speed 2,300 r/min, oil speed 3,000 r/min, mass about 1200 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32921XA?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32921XA); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32921XA designation encode the 105 mm bore?", "a": "last two digits 21 are the ISO bore code, ×5 = 105 mm (codes 00–03 use the 10/12/15/17 exception table). The 145 mm OD and 25 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32921XA list two speeds, 2,300 and 3,000 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32921XA at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32921XA mean?", "a": "Suffix reading on 32921XA: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32921XA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32921xa", "○32921xa", "32921XA" ], "locale_variants": {} }, { "sku": "32021XU", "brand": "NTN", "manufacturer_designation": "NTN 32021XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 105, "D_mm": 160, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 223, "static_load_kN": 335, "fatigue_load_limit_kN": 37.5, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 2440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32021XU is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 105×160 mm ISO 355 envelope, with 35 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32021XU by the metric ISO 355 number (ISO series abbreviation 4DC): 105 mm bore, 160 mm OD. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Selection: C 223 kN against C0 335 kN gives a C0/C ratio of 1.50 for the 105 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 32021XU; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 105 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 2440 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 35 mm section of 32021XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 105 mm bore smears the roller ends against the rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 105 mm shoulder geometry, because retrofitting flips the cups.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 105 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Replacing one half of an adjusted pair without resetting end play negates the 35 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 223/335 kN ratings and 37.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32021XU (ISO 355 4DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32021XU?", "a": "32021XU is a metric 4T tapered roller bearing to ISO 355: 105 mm bore, 160 mm outside diameter and 35 mm assembled width T (4.134 × 6.299 × 1.378 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 223 kN, C0 335 kN, Pu 37.5 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 2440 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32021XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32021XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32021XU designation encode the 105 mm bore and what is 4DC?", "a": "last two digits 21 are the ISO bore code, ×5 = 105 mm (codes 00–03 use the 10/12/15/17 exception table). The 160 mm OD and 35 mm assembled T follow the ISO 355 dimension-series plan. 4DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32021XU list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32021XU at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32021XU mean?", "a": "Suffix reading on 32021XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32021XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32021xu", "4dc", "32021XU" ], "locale_variants": {} }, { "sku": "33021U", "brand": "NTN", "manufacturer_designation": "NTN 33021U", "series": "33000-series", "type": "tapered_roller", "d_mm": 105, "D_mm": 160, "B_mm": 43, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 272, "static_load_kN": 420, "fatigue_load_limit_kN": 47, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 3000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33021U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 105×160 mm ISO 355 envelope, with 43 mm overall assembled width T. The last two digits 21 are the ISO bore code, ×5 = 105 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 43 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 33021U, not only the raceway. Selection: C 272 kN against C0 420 kN gives a C0/C ratio of 1.54 for the 105 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 33021U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 105 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3000 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 43 mm section of 33021U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 105 mm bore smears the roller ends against the rib.", "Minimum load matters at high speed: an unloaded 33021U at a large fraction of 2,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Do not confuse T (43 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 105 mm shoulder geometry, because retrofitting flips the cups.", "The 272/420 kN ratings and 47 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33021U (ISO 355 2DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33021U?", "a": "33021U is a metric 4T tapered roller bearing to ISO 355: 105 mm bore, 160 mm outside diameter and 43 mm assembled width T (4.134 × 6.299 × 1.693 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 272 kN, C0 420 kN, Pu 47 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 3000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33021U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33021U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33021U designation encode the 105 mm bore and what is 2DE?", "a": "last two digits 21 are the ISO bore code, ×5 = 105 mm (codes 00–03 use the 10/12/15/17 exception table). The 160 mm OD and 43 mm assembled T follow the ISO 355 dimension-series plan. 2DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33021U list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33021U at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33021U mean?", "a": "Suffix reading on 33021U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33021U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2de", "33021u", "33021U" ], "locale_variants": {} }, { "sku": "30221U", "brand": "NTN", "manufacturer_designation": "NTN 30221U", "series": "30200-series", "type": "tapered_roller", "d_mm": 105, "D_mm": 190, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 320, "static_load_kN": 380, "fatigue_load_limit_kN": 41, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2500, "weight_g": 4450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30221U in the standard-section 30200 family: 105 mm bore, 190 mm cup OD, 39 mm T, with a grease limiting speed of 1,900 r/min and an oil-lubricated ceiling of 2,500 r/min. The last two digits 21 are the ISO bore code, ×5 = 105 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 39 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Suffix reading on 30221U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. The two speed columns differ by a factor of .76 (grease/limiting 1,900 vs oil 2,500 r/min); heat generation at the cone rib decides which lubrication a real 30221U arrangement can sustain. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 30221U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 105 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 4450 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The standard-section 30200 family at 105 mm bore (190×39 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,500 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 105 mm shoulder geometry, because retrofitting flips the cups.", "Grease packs must leave free volume in the 39 mm-wide set; over-greasing a paired bearing churning at the 2,500 r/min oil-band speed raises temperature and destroys the preload setting.", "ISO 355 makes the 105×190 mm envelope interchangeable but not the ratings: NTN prints 320/380 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 320/380 kN ratings and 41 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30221U (ISO 355 3FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30221U?", "a": "30221U is a metric 4T tapered roller bearing to ISO 355: 105 mm bore, 190 mm outside diameter and 39 mm assembled width T (4.134 × 7.48 × 1.535 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 320 kN, C0 380 kN, Pu 41 kN, grease limiting speed 1,900 r/min, oil speed 2,500 r/min, mass about 4450 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30221U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30221U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30221U designation encode the 105 mm bore and what is 3FB?", "a": "last two digits 21 are the ISO bore code, ×5 = 105 mm (codes 00–03 use the 10/12/15/17 exception table). The 190 mm OD and 39 mm assembled T follow the ISO 355 dimension-series plan. 3FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30221U list two speeds, 1,900 and 2,500 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30221U at 2,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30221U mean?", "a": "Suffix reading on 30221U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30221U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30221u", "3fb", "30221U" ], "locale_variants": {} }, { "sku": "32221U", "brand": "NTN", "manufacturer_designation": "NTN 32221U", "series": "32200-series", "type": "tapered_roller", "d_mm": 105, "D_mm": 190, "B_mm": 53, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 420, "static_load_kN": 540, "fatigue_load_limit_kN": 59, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2500, "weight_g": 6230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32221U in the heavy-section 32200 family: 105 mm bore, 190 mm cup OD, 53 mm T, with a grease limiting speed of 1,900 r/min and an oil-lubricated ceiling of 2,500 r/min. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32221U by the metric ISO 355 number (ISO series abbreviation 3FC): 105 mm bore, 190 mm OD. At 420 kN C the bearing offers about 4.0 kN of dynamic capacity per millimetre of the 105 mm bore — compare any substitution on this ratio and the 53 mm assembled T, not on bore alone. The 4.0 kN-per-mm-bore capacity figure for 32221U summarises the 420 kN rating over 105 mm bore; use it to sanity-check an interchange candidate before swapping brands. Fillet radii must clear the ring chamfers of the 190 mm cup and 105 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 105 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 6230 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The heavy-section 32200 family at 105 mm bore (190×53 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,500 r/min oil ceiling.", "Do not confuse T (53 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Open 32221U units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,900 r/min grease figure is meaningless once water reaches the cone rib.", "Open 32221U units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,900 r/min grease figure is meaningless once water reaches the cone rib.", "The 420/540 kN ratings and 59 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32221U (ISO 355 3FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32221U?", "a": "32221U is a metric 4T tapered roller bearing to ISO 355: 105 mm bore, 190 mm outside diameter and 53 mm assembled width T (4.134 × 7.48 × 2.087 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 420 kN, C0 540 kN, Pu 59 kN, grease limiting speed 1,900 r/min, oil speed 2,500 r/min, mass about 6230 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32221U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32221U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32221U designation encode the 105 mm bore and what is 3FC?", "a": "last two digits 21 are the ISO bore code, ×5 = 105 mm (codes 00–03 use the 10/12/15/17 exception table). The 190 mm OD and 53 mm assembled T follow the ISO 355 dimension-series plan. 3FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32221U list two speeds, 1,900 and 2,500 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32221U at 2,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32221U mean?", "a": "Suffix reading on 32221U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32221U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32221u", "3fc", "32221U" ], "locale_variants": {} }, { "sku": "30321U", "brand": "NTN", "manufacturer_designation": "NTN 30321U", "series": "30300-series", "type": "tapered_roller", "d_mm": 105, "D_mm": 225, "B_mm": 53.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 485, "static_load_kN": 535, "fatigue_load_limit_kN": 56, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2300, "weight_g": 9370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 105 mm bore tapered roller position as 30321U: one cone assembly, one cup, line-contact rollers and a steel cage, rated 485 kN basic dynamic and 535 kN static on the large-OD 30300 family with the steeper contact angle. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30321U resolves to 105 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. NTN grades 4T metric bearings as open bearings without integral seals; at 105 mm bore the application supplies the seals and the grease fill or oil supply to the 2GB ISO 355 assembly. Speed planning uses both catalogue columns: grease 1,700 r/min is the cage/rib mechanical ceiling for 30321U, oil 2,300 r/min is available with circulating oil — a 600 r/min margin at this size. Mount the 105 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30321U.", "applications": [ "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 105 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 9370 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 105 mm bore; do not swap to the lighter family without re-checking the 1,700 r/min grease limit and the thrust load split.", "The 60.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30321U or the ring will bottom out on the radius instead of the shoulder face.", "The 60.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30321U or the ring will bottom out on the radius instead of the shoulder face.", "The 60.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30321U or the ring will bottom out on the radius instead of the shoulder face.", "The 485/535 kN ratings and 56 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30321U (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30321U?", "a": "30321U is a metric 4T tapered roller bearing to ISO 355: 105 mm bore, 225 mm outside diameter and 53.5 mm assembled width T (4.134 × 8.858 × 2.106 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 485 kN, C0 535 kN, Pu 56 kN, grease limiting speed 1,700 r/min, oil speed 2,300 r/min, mass about 9370 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30321U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30321U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30321U designation encode the 105 mm bore and what is 2GB?", "a": "last two digits 21 are the ISO bore code, ×5 = 105 mm (codes 00–03 use the 10/12/15/17 exception table). The 225 mm OD and 53.5 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30321U list two speeds, 1,700 and 2,300 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30321U at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30321U mean?", "a": "Suffix reading on 30321U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30321U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30321u", "30321U" ], "locale_variants": {} }, { "sku": "31321XU", "brand": "NTN", "manufacturer_designation": "NTN 31321XU", "series": "31300-series", "type": "tapered_roller", "d_mm": 105, "D_mm": 225, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 420, "static_load_kN": 470, "fatigue_load_limit_kN": 49, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2300, "weight_g": 9650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 31321XU denotes the steep-angle 31300 family for high axial load share of metric tapered roller bearings, 105 mm bore, 225 mm outside diameter and 58 mm assembled width T (4.134 × 8.858 × 2.283 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 7GB, which is the maker-neutral cross-reference for the 105×225 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 31321XU cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Imperial cross-check for the drawing: 105×225×58 mm is 4.134 × 8.858 × 2.283 in; ISO 355 makes the envelope interchangeable but C/C0, 420/470 kN, is NTN-specific. Mount the 105 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 31321XU.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 105 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 9650 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the steep-angle 31300 family for high axial load share raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 105 mm bore; do not swap to the lighter family without re-checking the 1,700 r/min grease limit and the thrust load split.", "Grease packs must leave free volume in the 58 mm-wide set; over-greasing a paired bearing churning at the 2,300 r/min oil-band speed raises temperature and destroys the preload setting.", "Grease packs must leave free volume in the 58 mm-wide set; over-greasing a paired bearing churning at the 2,300 r/min oil-band speed raises temperature and destroys the preload setting.", "Do not confuse T (58 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 420/470 kN ratings and 49 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 31321XU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 31321XU?", "a": "31321XU is a metric 4T tapered roller bearing to ISO 355: 105 mm bore, 225 mm outside diameter and 58 mm assembled width T (4.134 × 8.858 × 2.283 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 420 kN, C0 470 kN, Pu 49 kN, grease limiting speed 1,700 r/min, oil speed 2,300 r/min, mass about 9650 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 31321XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (31321XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 31321XU designation encode the 105 mm bore and what is 7GB?", "a": "last two digits 21 are the ISO bore code, ×5 = 105 mm (codes 00–03 use the 10/12/15/17 exception table). The 225 mm OD and 58 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 31321XU list two speeds, 1,700 and 2,300 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 31321XU at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 31321XU mean?", "a": "Suffix reading on 31321XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "31321XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "31321xu", "7gb", "31321XU" ], "locale_variants": {} }, { "sku": "32321U", "brand": "NTN", "manufacturer_designation": "NTN 32321U", "series": "32300-series", "type": "tapered_roller", "d_mm": 105, "D_mm": 225, "B_mm": 81.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 680, "static_load_kN": 825, "fatigue_load_limit_kN": 87, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2300, "weight_g": 14700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 105 mm bore tapered roller position as 32321U: one cone assembly, one cup, line-contact rollers and a steel cage, rated 680 kN basic dynamic and 825 kN static on the extra-heavy 32300 family. Digit by digit, the bare number identifies the extra-heavy 32300 family and a bore code resolving to 105 mm; 225 mm OD and 81.5 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32321U, not only the raceway. The two speed columns differ by a factor of .74 (grease/limiting 1,700 vs oil 2,300 r/min); heat generation at the cone rib decides which lubrication a real 32321U arrangement can sustain. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 105 mm pair is misadjusted and the 81.5 mm T set will edge-load in service.", "applications": [ "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "Mount the 105 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 14700 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 105 mm bore (225×81.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,300 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 105 mm shoulder geometry, because retrofitting flips the cups.", "Never fit the 105 mm cone by hammering the 225 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 105 mm shoulder geometry, because retrofitting flips the cups.", "The 680/825 kN ratings and 87 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32321U (ISO 355 2GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32321U?", "a": "32321U is a metric 4T tapered roller bearing to ISO 355: 105 mm bore, 225 mm outside diameter and 81.5 mm assembled width T (4.134 × 8.858 × 3.209 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 680 kN, C0 825 kN, Pu 87 kN, grease limiting speed 1,700 r/min, oil speed 2,300 r/min, mass about 14700 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32321U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32321U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32321U designation encode the 105 mm bore and what is 2GD?", "a": "last two digits 21 are the ISO bore code, ×5 = 105 mm (codes 00–03 use the 10/12/15/17 exception table). The 225 mm OD and 81.5 mm assembled T follow the ISO 355 dimension-series plan. 2GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32321U list two speeds, 1,700 and 2,300 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32321U at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32321U mean?", "a": "Suffix reading on 32321U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32321U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gd", "32321u", "32321U" ], "locale_variants": {} }, { "sku": "32922XA", "brand": "NTN", "manufacturer_designation": "NTN 32922XA", "series": "32900-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 150, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 141, "static_load_kN": 226, "fatigue_load_limit_kN": 25.5, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 2900, "weight_g": 1240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32922XA in the extra-light thin-section 32900 family: 110 mm bore, 150 mm cup OD, 25 mm T, with a grease limiting speed of 2,200 r/min and an oil-lubricated ceiling of 2,900 r/min. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32922XA resolves to 110 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Selection: C 141 kN against C0 226 kN gives a C0/C ratio of 1.60 for the 110 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 110 mm pair is misadjusted and the 25 mm T set will edge-load in service.", "applications": [ "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 110 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1240 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 25 mm section of 32922XA is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 110 mm bore smears the roller ends against the rib.", "ISO 355 makes the 110×150 mm envelope interchangeable but not the ratings: NTN prints 141/226 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32922XA by size alone can deliver the wrong contact-angle execution for a pinion position.", "Replacing one half of an adjusted pair without resetting end play negates the 25 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 141/226 kN ratings and 25.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32922XA; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32922XA?", "a": "32922XA is a metric 4T tapered roller bearing to ISO 355: 110 mm bore, 150 mm outside diameter and 25 mm assembled width T (4.331 × 5.906 × 0.984 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 141 kN, C0 226 kN, Pu 25.5 kN, grease limiting speed 2,200 r/min, oil speed 2,900 r/min, mass about 1240 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32922XA?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32922XA); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32922XA designation encode the 110 mm bore?", "a": "last two digits 22 are the ISO bore code, ×5 = 110 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 25 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32922XA list two speeds, 2,200 and 2,900 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32922XA at 2,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32922XA mean?", "a": "Suffix reading on 32922XA: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32922XA", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32922xa", "○32922xa", "32922XA" ], "locale_variants": {} }, { "sku": "32022XU", "brand": "NTN", "manufacturer_designation": "NTN 32022XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 170, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 261, "static_load_kN": 390, "fatigue_load_limit_kN": 43, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2700, "weight_g": 3070, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 110 mm bore tapered roller position as 32022XU: one cone assembly, one cup, line-contact rollers and a steel cage, rated 261 kN basic dynamic and 390 kN static on the low-section 32000 family tuned for low friction. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4DC, which is the maker-neutral cross-reference for the 110×170 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN grades 4T metric bearings as open bearings without integral seals; at 110 mm bore the application supplies the seals and the grease fill or oil supply to the 4DC ISO 355 assembly. Speed planning uses both catalogue columns: grease 2,000 r/min is the cage/rib mechanical ceiling for 32022XU, oil 2,700 r/min is available with circulating oil — a 700 r/min margin at this size. Mount the 110 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32022XU.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "Mount the 110 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3070 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 38 mm section of 32022XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 110 mm bore smears the roller ends against the rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 110 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Replacing one half of an adjusted pair without resetting end play negates the 38 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 30.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32022XU or the ring will bottom out on the radius instead of the shoulder face.", "The 261/390 kN ratings and 43 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32022XU (ISO 355 4DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32022XU?", "a": "32022XU is a metric 4T tapered roller bearing to ISO 355: 110 mm bore, 170 mm outside diameter and 38 mm assembled width T (4.331 × 6.693 × 1.496 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 261 kN, C0 390 kN, Pu 43 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 3070 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32022XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32022XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32022XU designation encode the 110 mm bore and what is 4DC?", "a": "last two digits 22 are the ISO bore code, ×5 = 110 mm (codes 00–03 use the 10/12/15/17 exception table). The 170 mm OD and 38 mm assembled T follow the ISO 355 dimension-series plan. 4DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32022XU list two speeds, 2,000 and 2,700 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32022XU at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32022XU mean?", "a": "Suffix reading on 32022XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32022XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=170", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32022xu", "4dc", "32022XU" ], "locale_variants": {} }, { "sku": "33022U", "brand": "NTN", "manufacturer_designation": "NTN 33022U", "series": "33000-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 170, "B_mm": 47, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 320, "static_load_kN": 500, "fatigue_load_limit_kN": 55.5, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2700, "weight_g": 3840, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33022U is the NTN 4T catalogue entry for a 110×170×47 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Digit by digit, the bare number identifies the slim 33000 family and a bore code resolving to 110 mm; 170 mm OD and 47 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. 2203E lists two speed ceilings for 33022U: 2,000 r/min with grease lubrication (the limiting speed) and 2,700 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Speed planning uses both catalogue columns: grease 2,000 r/min is the cage/rib mechanical ceiling for 33022U, oil 2,700 r/min is available with circulating oil — a 700 r/min margin at this size. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 110 mm pair is misadjusted and the 47 mm T set will edge-load in service.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 110 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3840 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The thin 47 mm section of 33022U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 110 mm bore smears the roller ends against the rib.", "Do not confuse T (47 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "ISO 355 makes the 110×170 mm envelope interchangeable but not the ratings: NTN prints 320/500 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Grease packs must leave free volume in the 47 mm-wide set; over-greasing a paired bearing churning at the 2,700 r/min oil-band speed raises temperature and destroys the preload setting.", "The 320/500 kN ratings and 55.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33022U (ISO 355 2DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33022U?", "a": "33022U is a metric 4T tapered roller bearing to ISO 355: 110 mm bore, 170 mm outside diameter and 47 mm assembled width T (4.331 × 6.693 × 1.85 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 320 kN, C0 500 kN, Pu 55.5 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 3840 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33022U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33022U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33022U designation encode the 110 mm bore and what is 2DE?", "a": "last two digits 22 are the ISO bore code, ×5 = 110 mm (codes 00–03 use the 10/12/15/17 exception table). The 170 mm OD and 47 mm assembled T follow the ISO 355 dimension-series plan. 2DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33022U list two speeds, 2,000 and 2,700 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33022U at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33022U mean?", "a": "Suffix reading on 33022U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33022U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2de", "33022u", "33022U" ], "locale_variants": {} }, { "sku": "33122UE1", "brand": "NTN", "manufacturer_designation": "NTN 33122UE1", "series": "33100-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 180, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 400, "static_load_kN": 610, "fatigue_load_limit_kN": 66.5, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2600, "weight_g": 5520, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 110 mm shaft with a thrust component, NTN lists 33122UE1, a metric 4T tapered roller bearing of 400 kN C and 610 kN C0 inside the 180 mm OD, 56 mm-wide assembled set. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 33122UE1 resolves to 110 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. At 400 kN C the bearing offers about 3.6 kN of dynamic capacity per millimetre of the 110 mm bore — compare any substitution on this ratio and the 56 mm assembled T, not on bore alone. The 35.0 mm section height over the 110 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. When pairing 33122UE1 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 110 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 5520 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The light-wide 33100 family at 110 mm bore (180×56 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,600 r/min oil ceiling.", "The 35.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33122UE1 or the ring will bottom out on the radius instead of the shoulder face.", "ISO 355 makes the 110×180 mm envelope interchangeable but not the ratings: NTN prints 400/610 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Open 33122UE1 units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,900 r/min grease figure is meaningless once water reaches the cone rib.", "The 400/610 kN ratings and 66.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33122UE1 (ISO 355 3FE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33122UE1?", "a": "33122UE1 is a metric 4T tapered roller bearing to ISO 355: 110 mm bore, 180 mm outside diameter and 56 mm assembled width T (4.331 × 7.087 × 2.205 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 400 kN, C0 610 kN, Pu 66.5 kN, grease limiting speed 1,900 r/min, oil speed 2,600 r/min, mass about 5520 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33122UE1?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33122UE1); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33122UE1 designation encode the 110 mm bore and what is 3FE?", "a": "last two digits E1 are the ISO bore code, ×5 = 110 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 56 mm assembled T follow the ISO 355 dimension-series plan. 3FE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33122UE1 list two speeds, 1,900 and 2,600 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33122UE1 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33122UE1 mean?", "a": "Suffix reading on 33122UE1: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33122UE1", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33122ue1", "3fe", "33122UE1" ], "locale_variants": {} }, { "sku": "30222U", "brand": "NTN", "manufacturer_designation": "NTN 30222U", "series": "30200-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 200, "B_mm": 41, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 360, "static_load_kN": 435, "fatigue_load_limit_kN": 46.5, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 5190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30222U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 110×200 mm ISO 355 envelope, with 41 mm overall assembled width T. Digit by digit, the bare number identifies the standard-section 30200 family and a bore code resolving to 110 mm; 200 mm OD and 41 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN grades 4T metric bearings as open bearings without integral seals; at 110 mm bore the application supplies the seals and the grease fill or oil supply to the 3FB ISO 355 assembly. Selection: C 360 kN against C0 435 kN gives a C0/C ratio of 1.21 for the 110 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 110 mm pair is misadjusted and the 41 mm T set will edge-load in service.", "applications": [ "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts", "large conveyor and bucket-elevator pulleys" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "Mount the 110 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 5190 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The standard-section 30200 family at 110 mm bore (200×41 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,400 r/min oil ceiling.", "Open 30222U units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,800 r/min grease figure is meaningless once water reaches the cone rib.", "Minimum load matters at high speed: an unloaded 30222U at a large fraction of 1,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 45.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30222U or the ring will bottom out on the radius instead of the shoulder face.", "The 360/435 kN ratings and 46.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30222U (ISO 355 3FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30222U?", "a": "30222U is a metric 4T tapered roller bearing to ISO 355: 110 mm bore, 200 mm outside diameter and 41 mm assembled width T (4.331 × 7.874 × 1.614 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 360 kN, C0 435 kN, Pu 46.5 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 5190 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30222U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30222U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30222U designation encode the 110 mm bore and what is 3FB?", "a": "last two digits 22 are the ISO bore code, ×5 = 110 mm (codes 00–03 use the 10/12/15/17 exception table). The 200 mm OD and 41 mm assembled T follow the ISO 355 dimension-series plan. 3FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30222U list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30222U at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30222U mean?", "a": "Suffix reading on 30222U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30222U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30222u", "3fb", "30222U" ], "locale_variants": {} }, { "sku": "32222U", "brand": "NTN", "manufacturer_designation": "NTN 32222U", "series": "32200-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 200, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 465, "static_load_kN": 605, "fatigue_load_limit_kN": 65, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 7440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32222U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 110×200 mm ISO 355 envelope, with 56 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 3FC, which is the maker-neutral cross-reference for the 110×200 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32222U, not only the raceway. Imperial cross-check for the drawing: 110×200×56 mm is 4.331 × 7.874 × 2.205 in; ISO 355 makes the envelope interchangeable but C/C0, 465/605 kN, is NTN-specific. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32222U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 110 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 7440 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The heavy-section 32200 family at 110 mm bore (200×56 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,400 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 56 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 56 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 110 mm shoulder geometry, because retrofitting flips the cups.", "The 465/605 kN ratings and 65 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32222U (ISO 355 3FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32222U?", "a": "32222U is a metric 4T tapered roller bearing to ISO 355: 110 mm bore, 200 mm outside diameter and 56 mm assembled width T (4.331 × 7.874 × 2.205 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 465 kN, C0 605 kN, Pu 65 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 7440 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32222U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32222U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32222U designation encode the 110 mm bore and what is 3FC?", "a": "last two digits 22 are the ISO bore code, ×5 = 110 mm (codes 00–03 use the 10/12/15/17 exception table). The 200 mm OD and 56 mm assembled T follow the ISO 355 dimension-series plan. 3FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32222U list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32222U at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32222U mean?", "a": "Suffix reading on 32222U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32222U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32222u", "3fc", "32222U" ], "locale_variants": {} }, { "sku": "30322U", "brand": "NTN", "manufacturer_designation": "NTN 30322U", "series": "30300-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 240, "B_mm": 54.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 530, "static_load_kN": 585, "fatigue_load_limit_kN": 60, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2200, "weight_g": 11100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 110 mm shaft with a thrust component, NTN lists 30322U, a metric 4T tapered roller bearing of 530 kN C and 585 kN C0 inside the 240 mm OD, 54.5 mm-wide assembled set. The last two digits 22 are the ISO bore code, ×5 = 110 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 54.5 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The 65.0 mm radial section carries the roller complement across the 110–240 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The fatigue load limit Pu printed for 30322U is 60 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. When pairing 30322U with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "paper-machine press-section rolls", "large agricultural and forestry machine axles", "heavy industrial gearboxes and crane travel drives", "rolling-mill auxiliary and pinion-stand shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 110 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 11100 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 110 mm bore; do not swap to the lighter family without re-checking the 1,600 r/min grease limit and the thrust load split.", "ISO 355 makes the 110×240 mm envelope interchangeable but not the ratings: NTN prints 530/585 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 110 mm shoulder geometry, because retrofitting flips the cups.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30322U by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 530/585 kN ratings and 60 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30322U (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30322U?", "a": "30322U is a metric 4T tapered roller bearing to ISO 355: 110 mm bore, 240 mm outside diameter and 54.5 mm assembled width T (4.331 × 9.449 × 2.146 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 530 kN, C0 585 kN, Pu 60 kN, grease limiting speed 1,600 r/min, oil speed 2,200 r/min, mass about 11100 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30322U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30322U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30322U designation encode the 110 mm bore and what is 2GB?", "a": "last two digits 22 are the ISO bore code, ×5 = 110 mm (codes 00–03 use the 10/12/15/17 exception table). The 240 mm OD and 54.5 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30322U list two speeds, 1,600 and 2,200 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30322U at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30322U mean?", "a": "Suffix reading on 30322U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30322U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30322u", "30322U" ], "locale_variants": {} }, { "sku": "31322XU", "brand": "NTN", "manufacturer_designation": "NTN 31322XU", "series": "31300-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 240, "B_mm": 63, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 480, "static_load_kN": 535, "fatigue_load_limit_kN": 55, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2200, "weight_g": 11900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "31322XU is the NTN 4T catalogue entry for a 110×240×63 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 31322XU resolves to 110 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Suffix reading on 31322XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. Selection: C 480 kN against C0 535 kN gives a C0/C ratio of 1.11 for the 110 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Mount the 110 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 31322XU.", "applications": [ "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls", "large agricultural and forestry machine axles" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 110 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 11900 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The steeper contact angle of the steep-angle 31300 family for high axial load share raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 110 mm bore; do not swap to the lighter family without re-checking the 1,600 r/min grease limit and the thrust load split.", "Open 31322XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,600 r/min grease figure is meaningless once water reaches the cone rib.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 31322XU by size alone can deliver the wrong contact-angle execution for a pinion position.", "ISO 355 makes the 110×240 mm envelope interchangeable but not the ratings: NTN prints 480/535 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 480/535 kN ratings and 55 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 31322XU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 31322XU?", "a": "31322XU is a metric 4T tapered roller bearing to ISO 355: 110 mm bore, 240 mm outside diameter and 63 mm assembled width T (4.331 × 9.449 × 2.48 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 480 kN, C0 535 kN, Pu 55 kN, grease limiting speed 1,600 r/min, oil speed 2,200 r/min, mass about 11900 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 31322XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (31322XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 31322XU designation encode the 110 mm bore and what is 7GB?", "a": "last two digits 22 are the ISO bore code, ×5 = 110 mm (codes 00–03 use the 10/12/15/17 exception table). The 240 mm OD and 63 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 31322XU list two speeds, 1,600 and 2,200 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 31322XU at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 31322XU mean?", "a": "Suffix reading on 31322XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "31322XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "31322xu", "7gb", "31322XU" ], "locale_variants": {} }, { "sku": "32322U", "brand": "NTN", "manufacturer_designation": "NTN 32322U", "series": "32300-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 240, "B_mm": 84.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 785, "static_load_kN": 970, "fatigue_load_limit_kN": 99.5, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2200, "weight_g": 17600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 110 mm shaft with a thrust component, NTN lists 32322U, a metric 4T tapered roller bearing of 785 kN C and 970 kN C0 inside the 240 mm OD, 84.5 mm-wide assembled set. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32322U by the metric ISO 355 number (ISO series abbreviation 2GD): 110 mm bore, 240 mm OD. 2203E lists two speed ceilings for 32322U: 1,600 r/min with grease lubrication (the limiting speed) and 2,200 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Selection: C 785 kN against C0 970 kN gives a C0/C ratio of 1.24 for the 110 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 32322U washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "large conveyor and bucket-elevator pulleys", "mineral-processing feeder and crusher auxiliaries", "marine winch and deck-machinery shafts", "paper-machine press-section rolls" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "Mount the 110 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 17600 g ring mass makes cocking during fitting a direct raceway-brinelling risk.", "The extra-heavy 32300 family at 110 mm bore (240×84.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,200 r/min oil ceiling.", "Open 32322U units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,600 r/min grease figure is meaningless once water reaches the cone rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 110 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Grease packs must leave free volume in the 84.5 mm-wide set; over-greasing a paired bearing churning at the 2,200 r/min oil-band speed raises temperature and destroys the preload setting.", "The 785/970 kN ratings and 99.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32322U (ISO 355 2GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32322U?", "a": "32322U is a metric 4T tapered roller bearing to ISO 355: 110 mm bore, 240 mm outside diameter and 84.5 mm assembled width T (4.331 × 9.449 × 3.327 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 785 kN, C0 970 kN, Pu 99.5 kN, grease limiting speed 1,600 r/min, oil speed 2,200 r/min, mass about 17600 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32322U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32322U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32322U designation encode the 110 mm bore and what is 2GD?", "a": "last two digits 22 are the ISO bore code, ×5 = 110 mm (codes 00–03 use the 10/12/15/17 exception table). The 240 mm OD and 84.5 mm assembled T follow the ISO 355 dimension-series plan. 2GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32322U list two speeds, 1,600 and 2,200 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32322U at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32322U mean?", "a": "Suffix reading on 32322U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32322U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gd", "32322u", "32322U" ], "locale_variants": {} }, { "sku": "32924-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32924", "series": "32900-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 165, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 131, "static_load_kN": 205, "fatigue_load_limit_kN": 22.5, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2600, "weight_g": 1650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 120 mm bore tapered roller position as 32924: one cone assembly, one cup, line-contact rollers and a steel cage, rated 131 kN basic dynamic and 205 kN static on the extra-light thin-section 32900 family. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 120 mm; 165 mm OD and 29 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32924, not only the raceway. The 1.1 kN-per-mm-bore capacity figure for 32924 summarises the 131 kN rating over 120 mm bore; use it to sanity-check an interchange candidate before swapping brands. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32924 arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 120 mm bore the 32924 set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 131 kN C level.", "The thin 29 mm section of 32924 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 120 mm bore smears the roller ends against the rib.", "Minimum load matters at high speed: an unloaded 32924 at a large fraction of 2,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Grease packs must leave free volume in the 29 mm-wide set; over-greasing a paired bearing churning at the 2,600 r/min oil-band speed raises temperature and destroys the preload setting.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 120 mm shoulder geometry, because retrofitting flips the cups.", "The 131/205 kN ratings and 22.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32924; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32924?", "a": "32924 is a metric 4T tapered roller bearing to ISO 355: 120 mm bore, 165 mm outside diameter and 29 mm assembled width T (4.724 × 6.496 × 1.142 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 131 kN, C0 205 kN, Pu 22.5 kN, grease limiting speed 2,000 r/min, oil speed 2,600 r/min, mass about 1650 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32924?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32924); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32924 designation encode the 120 mm bore?", "a": "last two digits 24 are the ISO bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table). The 165 mm OD and 29 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32924 list two speeds, 2,000 and 2,600 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32924 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32924 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32924", "equiv_brand": "SKF", "level": "partial", "note": "Same 120×165×29 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "○32924", "32924", "32924-NTN" ], "locale_variants": {} }, { "sku": "32924XU", "brand": "NTN", "manufacturer_designation": "NTN 32924XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 165, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 180, "static_load_kN": 294, "fatigue_load_limit_kN": 32, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2600, "weight_g": 1760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32924XU is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 120×165 mm ISO 355 envelope, with 29 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32924XU by the metric ISO 355 number (ISO series abbreviation 2CC): 120 mm bore, 165 mm OD. At 180 kN C the bearing offers about 1.5 kN of dynamic capacity per millimetre of the 120 mm bore — compare any substitution on this ratio and the 29 mm assembled T, not on bore alone. Speed planning uses both catalogue columns: grease 2,000 r/min is the cage/rib mechanical ceiling for 32924XU, oil 2,600 r/min is available with circulating oil — a 600 r/min margin at this size. Fillet radii must clear the ring chamfers of the 165 mm cup and 120 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 120 mm bore the 32924XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 180 kN C level.", "The thin 29 mm section of 32924XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 120 mm bore smears the roller ends against the rib.", "ISO 355 makes the 120×165 mm envelope interchangeable but not the ratings: NTN prints 180/294 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 120 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Open 32924XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 2,000 r/min grease figure is meaningless once water reaches the cone rib.", "The 180/294 kN ratings and 32 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32924XU (ISO 355 2CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32924XU?", "a": "32924XU is a metric 4T tapered roller bearing to ISO 355: 120 mm bore, 165 mm outside diameter and 29 mm assembled width T (4.724 × 6.496 × 1.142 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 180 kN, C0 294 kN, Pu 32 kN, grease limiting speed 2,000 r/min, oil speed 2,600 r/min, mass about 1760 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32924XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32924XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32924XU designation encode the 120 mm bore and what is 2CC?", "a": "last two digits 24 are the ISO bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table). The 165 mm OD and 29 mm assembled T follow the ISO 355 dimension-series plan. 2CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32924XU list two speeds, 2,000 and 2,600 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32924XU at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32924XU mean?", "a": "Suffix reading on 32924XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32924XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2cc", "32924xu", "32924XU" ], "locale_variants": {} }, { "sku": "T4CB120", "brand": "NTN", "manufacturer_designation": "NTN T4CB120", "series": "T4CB-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 170, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 171, "static_load_kN": 235, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2600, "weight_g": 1690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 120 mm bore tapered roller position as T4CB120: one cone assembly, one cup, line-contact rollers and a steel cage, rated 171 kN basic dynamic and 235 kN static on the large-size ISO 355 tapered-roller family. Digit by digit, the bare number identifies the large-size ISO 355 tapered-roller family and a bore code resolving to 120 mm; 170 mm OD and 27 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 120 mm bore directly, and remains an open 4T execution ordered under its own code. Speed planning uses both catalogue columns: grease 1,900 r/min is the cage/rib mechanical ceiling for T4CB120, oil 2,600 r/min is available with circulating oil — a 700 r/min margin at this size. Mount the 120 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of T4CB120.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 120 mm bore the T4CB120 set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 171 kN C level.", "The large-size ISO 355 tapered-roller family at 120 mm bore (170×27 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,600 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded T4CB120 at a large fraction of 1,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Replacing one half of an adjusted pair without resetting end play negates the 27 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ISO 355 makes the 120×170 mm envelope interchangeable but not the ratings: NTN prints 171/235 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 171/235 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T4CB120 (ISO 355 4CB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T4CB120?", "a": "T4CB120 is a metric 4T tapered roller bearing to ISO 355: 120 mm bore, 170 mm outside diameter and 27 mm assembled width T (4.724 × 6.693 × 1.063 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 171 kN, C0 235 kN (2203E prints no Pu for this size), grease limiting speed 1,900 r/min, oil speed 2,600 r/min, mass about 1690 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T4CB120?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T4CB120); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T4CB120 designation encode the 120 mm bore and what is 4CB?", "a": "trailing dimension block 120 prints the 120 mm bore directly for this large-size T-code. The 170 mm OD and 27 mm assembled T follow the ISO 355 dimension-series plan. 4CB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T4CB120 list two speeds, 1,900 and 2,600 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T4CB120 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T4CB120 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 120 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T4CB120", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4cb", "4t-t4cb120", "t4cb120", "T4CB120" ], "locale_variants": {} }, { "sku": "32024XU", "brand": "NTN", "manufacturer_designation": "NTN 32024XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 180, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 272, "static_load_kN": 420, "fatigue_load_limit_kN": 45.5, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2500, "weight_g": 3290, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32024XU belongs to the NTN metric 4T tapered roller range (low-section 32000 family tuned for low friction); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32024XU by the metric ISO 355 number (ISO series abbreviation 4DC): 120 mm bore, 180 mm OD. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32024XU, since running clearance is set during assembly. The two speed columns differ by a factor of .72 (grease/limiting 1,800 vs oil 2,500 r/min); heat generation at the cone rib decides which lubrication a real 32024XU arrangement can sustain. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32024XU arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 120 mm bore the 32024XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 272 kN C level.", "The thin 38 mm section of 32024XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 120 mm bore smears the roller ends against the rib.", "Grease packs must leave free volume in the 38 mm-wide set; over-greasing a paired bearing churning at the 2,500 r/min oil-band speed raises temperature and destroys the preload setting.", "Do not confuse T (38 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 120 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 272/420 kN ratings and 45.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32024XU (ISO 355 4DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32024XU?", "a": "32024XU is a metric 4T tapered roller bearing to ISO 355: 120 mm bore, 180 mm outside diameter and 38 mm assembled width T (4.724 × 7.087 × 1.496 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 272 kN, C0 420 kN, Pu 45.5 kN, grease limiting speed 1,800 r/min, oil speed 2,500 r/min, mass about 3290 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32024XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32024XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32024XU designation encode the 120 mm bore and what is 4DC?", "a": "last two digits 24 are the ISO bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 38 mm assembled T follow the ISO 355 dimension-series plan. 4DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32024XU list two speeds, 1,800 and 2,500 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32024XU at 2,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32024XU mean?", "a": "Suffix reading on 32024XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32024XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32024xu", "4dc", "32024XU" ], "locale_variants": {} }, { "sku": "33024U", "brand": "NTN", "manufacturer_designation": "NTN 33024U", "series": "33000-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 180, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 325, "static_load_kN": 520, "fatigue_load_limit_kN": 56.5, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2500, "weight_g": 4140, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 120 mm bore tapered roller position as 33024U: one cone assembly, one cup, line-contact rollers and a steel cage, rated 325 kN basic dynamic and 520 kN static on the slim 33000 family. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2DE, which is the maker-neutral cross-reference for the 120×180 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. Suffix reading on 33024U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. Catalogue mass of the 33024U set is 4140 g (0.163 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Mount the 120 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 33024U.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 120 mm bore the 33024U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 325 kN C level.", "The thin 48 mm section of 33024U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 120 mm bore smears the roller ends against the rib.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33024U by size alone can deliver the wrong contact-angle execution for a pinion position.", "Replacing one half of an adjusted pair without resetting end play negates the 48 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ISO 355 makes the 120×180 mm envelope interchangeable but not the ratings: NTN prints 325/520 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 325/520 kN ratings and 56.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33024U (ISO 355 2DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33024U?", "a": "33024U is a metric 4T tapered roller bearing to ISO 355: 120 mm bore, 180 mm outside diameter and 48 mm assembled width T (4.724 × 7.087 × 1.89 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 325 kN, C0 520 kN, Pu 56.5 kN, grease limiting speed 1,800 r/min, oil speed 2,500 r/min, mass about 4140 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33024U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33024U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33024U designation encode the 120 mm bore and what is 2DE?", "a": "last two digits 24 are the ISO bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 48 mm assembled T follow the ISO 355 dimension-series plan. 2DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33024U list two speeds, 1,800 and 2,500 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33024U at 2,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33024U mean?", "a": "Suffix reading on 33024U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33024U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2de", "33024u", "33024U" ], "locale_variants": {} }, { "sku": "33124U", "brand": "NTN", "manufacturer_designation": "NTN 33124U", "series": "33100-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 200, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 510, "static_load_kN": 760, "fatigue_load_limit_kN": 80.5, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2300, "weight_g": 7670, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33124U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 120×200 mm ISO 355 envelope, with 62 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 33124U by the metric ISO 355 number (ISO series abbreviation 3FE): 120 mm bore, 200 mm OD. NTN grades 4T metric bearings as open bearings without integral seals; at 120 mm bore the application supplies the seals and the grease fill or oil supply to the 3FE ISO 355 assembly. Grease relubrication at 1,800 r/min limiting speed targets the rib contact; if the drive needs 2,300 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 33124U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 120 mm bore the 33124U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 510 kN C level.", "The light-wide 33100 family at 120 mm bore (200×62 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,300 r/min oil ceiling.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 120 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 120 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 40.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 33124U or the ring will bottom out on the radius instead of the shoulder face.", "The 510/760 kN ratings and 80.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33124U (ISO 355 3FE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33124U?", "a": "33124U is a metric 4T tapered roller bearing to ISO 355: 120 mm bore, 200 mm outside diameter and 62 mm assembled width T (4.724 × 7.874 × 2.441 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 510 kN, C0 760 kN, Pu 80.5 kN, grease limiting speed 1,800 r/min, oil speed 2,300 r/min, mass about 7670 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33124U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33124U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33124U designation encode the 120 mm bore and what is 3FE?", "a": "last two digits 24 are the ISO bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table). The 200 mm OD and 62 mm assembled T follow the ISO 355 dimension-series plan. 3FE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33124U list two speeds, 1,800 and 2,300 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33124U at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33124U mean?", "a": "Suffix reading on 33124U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33124U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "33124u", "3fe", "33124U" ], "locale_variants": {} }, { "sku": "30224U", "brand": "NTN", "manufacturer_designation": "NTN 30224U", "series": "30200-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 215, "B_mm": 43.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 385, "static_load_kN": 470, "fatigue_load_limit_kN": 49, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 6320, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30224U belongs to the NTN metric 4T tapered roller range (standard-section 30200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4FB, which is the maker-neutral cross-reference for the 120×215 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. The fatigue load limit Pu printed for 30224U is 49 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Mount the 120 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30224U.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 120 mm bore the 30224U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 385 kN C level.", "The standard-section 30200 family at 120 mm bore (215×43.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,200 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 30224U at a large fraction of 1,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 120 mm shoulder geometry, because retrofitting flips the cups.", "Replacing one half of an adjusted pair without resetting end play negates the 43.5 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 385/470 kN ratings and 49 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30224U (ISO 355 4FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30224U?", "a": "30224U is a metric 4T tapered roller bearing to ISO 355: 120 mm bore, 215 mm outside diameter and 43.5 mm assembled width T (4.724 × 8.465 × 1.713 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 385 kN, C0 470 kN, Pu 49 kN, grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 6320 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30224U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30224U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30224U designation encode the 120 mm bore and what is 4FB?", "a": "last two digits 24 are the ISO bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table). The 215 mm OD and 43.5 mm assembled T follow the ISO 355 dimension-series plan. 4FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30224U list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30224U at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30224U mean?", "a": "Suffix reading on 30224U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30224U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30224u", "4fb", "30224U" ], "locale_variants": {} }, { "sku": "32224U", "brand": "NTN", "manufacturer_designation": "NTN 32224U", "series": "32200-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 215, "B_mm": 61.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 510, "static_load_kN": 680, "fatigue_load_limit_kN": 71.5, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 9080, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32224U belongs to the NTN metric 4T tapered roller range (heavy-section 32200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. The last two digits 24 are the ISO bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 61.5 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Individually mounted, 32224U takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Selection: C 510 kN against C0 680 kN gives a C0/C ratio of 1.33 for the 120 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 120 mm pair is misadjusted and the 61.5 mm T set will edge-load in service.", "applications": [ "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 120 mm bore the 32224U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 510 kN C level.", "The heavy-section 32200 family at 120 mm bore (215×61.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,200 r/min oil ceiling.", "The 47.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32224U or the ring will bottom out on the radius instead of the shoulder face.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 120 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Never fit the 120 mm cone by hammering the 215 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 510/680 kN ratings and 71.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32224U (ISO 355 4FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32224U?", "a": "32224U is a metric 4T tapered roller bearing to ISO 355: 120 mm bore, 215 mm outside diameter and 61.5 mm assembled width T (4.724 × 8.465 × 2.421 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 510 kN, C0 680 kN, Pu 71.5 kN, grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 9080 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32224U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32224U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32224U designation encode the 120 mm bore and what is 4FD?", "a": "last two digits 24 are the ISO bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table). The 215 mm OD and 61.5 mm assembled T follow the ISO 355 dimension-series plan. 4FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32224U list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32224U at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32224U mean?", "a": "Suffix reading on 32224U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32224U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32224u", "4fd", "32224U" ], "locale_variants": {} }, { "sku": "30324U", "brand": "NTN", "manufacturer_designation": "NTN 30324U", "series": "30300-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 260, "B_mm": 59.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 620, "static_load_kN": 695, "fatigue_load_limit_kN": 69.5, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 14100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30324U in the large-OD 30300 family with the steeper contact angle: 120 mm bore, 260 mm cup OD, 59.5 mm T, with a grease limiting speed of 1,500 r/min and an oil-lubricated ceiling of 2,000 r/min. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30324U by the metric ISO 355 number (ISO series abbreviation 2GB): 120 mm bore, 260 mm OD. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 30324U cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The 70.0 mm section height over the 120 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 30324U arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 120 mm bore the 30324U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 620 kN C level.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 120 mm bore; do not swap to the lighter family without re-checking the 1,500 r/min grease limit and the thrust load split.", "Grease packs must leave free volume in the 59.5 mm-wide set; over-greasing a paired bearing churning at the 2,000 r/min oil-band speed raises temperature and destroys the preload setting.", "ISO 355 makes the 120×260 mm envelope interchangeable but not the ratings: NTN prints 620/695 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Do not confuse T (59.5 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 620/695 kN ratings and 69.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30324U (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30324U?", "a": "30324U is a metric 4T tapered roller bearing to ISO 355: 120 mm bore, 260 mm outside diameter and 59.5 mm assembled width T (4.724 × 10.236 × 2.343 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 620 kN, C0 695 kN, Pu 69.5 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 14100 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30324U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30324U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30324U designation encode the 120 mm bore and what is 2GB?", "a": "last two digits 24 are the ISO bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table). The 260 mm OD and 59.5 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30324U list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30324U at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30324U mean?", "a": "Suffix reading on 30324U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30324U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30324u", "30324U" ], "locale_variants": {} }, { "sku": "31324XU", "brand": "NTN", "manufacturer_designation": "NTN 31324XU", "series": "31300-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 260, "B_mm": 68, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 570, "static_load_kN": 655, "fatigue_load_limit_kN": 66, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 15200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "31324XU is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 120×260 mm ISO 355 envelope, with 68 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 7GB, which is the maker-neutral cross-reference for the 120×260 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The printed contact-angle geometry gives the steep-angle 31300 family for high axial load share its characteristic load split — at 570/655 kN (C/C0) the static rating is about 1.15× C, typical of tapered bearings proportioned for heavy combined duty. Imperial cross-check for the drawing: 120×260×68 mm is 4.724 × 10.236 × 2.677 in; ISO 355 makes the envelope interchangeable but C/C0, 570/655 kN, is NTN-specific. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 31324XU arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 120 mm bore the 31324XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 570 kN C level.", "The steeper contact angle of the steep-angle 31300 family for high axial load share raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 120 mm bore; do not swap to the lighter family without re-checking the 1,500 r/min grease limit and the thrust load split.", "Never fit the 120 mm cone by hammering the 260 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Replacing one half of an adjusted pair without resetting end play negates the 68 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Minimum load matters at high speed: an unloaded 31324XU at a large fraction of 1,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 570/655 kN ratings and 66 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 31324XU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 31324XU?", "a": "31324XU is a metric 4T tapered roller bearing to ISO 355: 120 mm bore, 260 mm outside diameter and 68 mm assembled width T (4.724 × 10.236 × 2.677 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 570 kN, C0 655 kN, Pu 66 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 15200 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 31324XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (31324XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 31324XU designation encode the 120 mm bore and what is 7GB?", "a": "last two digits 24 are the ISO bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table). The 260 mm OD and 68 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 31324XU list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 31324XU at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 31324XU mean?", "a": "Suffix reading on 31324XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "31324XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "31324xu", "7gb", "31324XU" ], "locale_variants": {} }, { "sku": "32324U", "brand": "NTN", "manufacturer_designation": "NTN 32324U", "series": "32300-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 260, "B_mm": 90.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 905, "static_load_kN": 1130, "fatigue_load_limit_kN": 114, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 22100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32324U in the extra-heavy 32300 family: 120 mm bore, 260 mm cup OD, 90.5 mm T, with a grease limiting speed of 1,500 r/min and an oil-lubricated ceiling of 2,000 r/min. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32324U resolves to 120 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Suffix reading on 32324U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. The fatigue load limit Pu printed for 32324U is 114 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. When pairing 32324U with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 120 mm bore the 32324U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 905 kN C level.", "The extra-heavy 32300 family at 120 mm bore (260×90.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,000 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 32324U at a large fraction of 1,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Grease packs must leave free volume in the 90.5 mm-wide set; over-greasing a paired bearing churning at the 2,000 r/min oil-band speed raises temperature and destroys the preload setting.", "ISO 355 makes the 120×260 mm envelope interchangeable but not the ratings: NTN prints 905/1130 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 905/1130 kN ratings and 114 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32324U (ISO 355 2GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32324U?", "a": "32324U is a metric 4T tapered roller bearing to ISO 355: 120 mm bore, 260 mm outside diameter and 90.5 mm assembled width T (4.724 × 10.236 × 3.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 905 kN, C0 1130 kN, Pu 114 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 22100 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32324U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32324U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32324U designation encode the 120 mm bore and what is 2GD?", "a": "last two digits 24 are the ISO bore code, ×5 = 120 mm (codes 00–03 use the 10/12/15/17 exception table). The 260 mm OD and 90.5 mm assembled T follow the ISO 355 dimension-series plan. 2GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32324U list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32324U at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32324U mean?", "a": "Suffix reading on 32324U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32324U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gd", "32324u", "32324U" ], "locale_variants": {} }, { "sku": "32926-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32926", "series": "32900-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 180, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 157, "static_load_kN": 252, "fatigue_load_limit_kN": 26.9, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 2240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 130 mm bore tapered roller position as 32926: one cone assembly, one cup, line-contact rollers and a steel cage, rated 157 kN basic dynamic and 252 kN static on the extra-light thin-section 32900 family. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 130×180 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32926 cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The 25.0 mm section height over the 130 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. When pairing 32926 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 130 mm bore the 32926 set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 157 kN C level.", "The thin 32 mm section of 32926 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 130 mm bore smears the roller ends against the rib.", "The 25.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32926 or the ring will bottom out on the radius instead of the shoulder face.", "Open 32926 units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,800 r/min grease figure is meaningless once water reaches the cone rib.", "Do not confuse T (32 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 157/252 kN ratings and 26.9 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32926; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32926?", "a": "32926 is a metric 4T tapered roller bearing to ISO 355: 130 mm bore, 180 mm outside diameter and 32 mm assembled width T (5.118 × 7.087 × 1.26 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 157 kN, C0 252 kN, Pu 26.9 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 2240 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32926?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32926); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32926 designation encode the 130 mm bore?", "a": "last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 32 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32926 list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32926 at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32926 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32926", "equiv_brand": "SKF", "level": "partial", "note": "Same 130×180×32 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "32926-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "○32926", "32926", "32926-NTN" ], "locale_variants": {} }, { "sku": "32926XU", "brand": "NTN", "manufacturer_designation": "NTN 32926XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 180, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 215, "static_load_kN": 350, "fatigue_load_limit_kN": 37.5, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 2410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32926XU belongs to the NTN metric 4T tapered roller range (extra-light thin-section 32900 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 130 mm; 180 mm OD and 32 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32926XU, since running clearance is set during assembly. The two speed columns differ by a factor of .75 (grease/limiting 1,800 vs oil 2,400 r/min); heat generation at the cone rib decides which lubrication a real 32926XU arrangement can sustain. Mount the 130 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32926XU.", "applications": [ "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 130 mm bore the 32926XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 215 kN C level.", "The thin 32 mm section of 32926XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 130 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 32 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 32926XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,800 r/min grease figure is meaningless once water reaches the cone rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 130 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 215/350 kN ratings and 37.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32926XU (ISO 355 2CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32926XU?", "a": "32926XU is a metric 4T tapered roller bearing to ISO 355: 130 mm bore, 180 mm outside diameter and 32 mm assembled width T (5.118 × 7.087 × 1.26 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 215 kN, C0 350 kN, Pu 37.5 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 2410 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32926XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32926XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32926XU designation encode the 130 mm bore and what is 2CC?", "a": "last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 32 mm assembled T follow the ISO 355 dimension-series plan. 2CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32926XU list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32926XU at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32926XU mean?", "a": "Suffix reading on 32926XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32926XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2cc", "32926xu", "32926XU" ], "locale_variants": {} }, { "sku": "32026XU", "brand": "NTN", "manufacturer_designation": "NTN 32026XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 200, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 350, "static_load_kN": 545, "fatigue_load_limit_kN": 57, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 5000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32026XU is the NTN 4T catalogue entry for a 130×200×45 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. The last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 45 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Suffix reading on 32026XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. The 35.0 mm section height over the 130 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Open 4T bearings need application seals; without them the grease at the cone rib of 32026XU washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 130 mm bore the 32026XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 350 kN C level.", "The thin 45 mm section of 32026XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 130 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 45 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Minimum load matters at high speed: an unloaded 32026XU at a large fraction of 1,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "ISO 355 makes the 130×200 mm envelope interchangeable but not the ratings: NTN prints 350/545 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 350/545 kN ratings and 57 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32026XU (ISO 355 4EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32026XU?", "a": "32026XU is a metric 4T tapered roller bearing to ISO 355: 130 mm bore, 200 mm outside diameter and 45 mm assembled width T (5.118 × 7.874 × 1.772 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 350 kN, C0 545 kN, Pu 57 kN, grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 5000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32026XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32026XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32026XU designation encode the 130 mm bore and what is 4EC?", "a": "last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table). The 200 mm OD and 45 mm assembled T follow the ISO 355 dimension-series plan. 4EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32026XU list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32026XU at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32026XU mean?", "a": "Suffix reading on 32026XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32026XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32026xu", "4ec", "32026XU" ], "locale_variants": {} }, { "sku": "33026U", "brand": "NTN", "manufacturer_designation": "NTN 33026U", "series": "33000-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 200, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 415, "static_load_kN": 660, "fatigue_load_limit_kN": 69.5, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2300, "weight_g": 6090, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 33026U denotes the slim 33000 family of metric tapered roller bearings, 130 mm bore, 200 mm outside diameter and 55 mm assembled width T (5.118 × 7.874 × 2.165 in) to the ISO 355 boundary plan. The last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 55 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The 35.0 mm radial section carries the roller complement across the 130–200 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Grease relubrication at 1,700 r/min limiting speed targets the rib contact; if the drive needs 2,300 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Fillet radii must clear the ring chamfers of the 200 mm cup and 130 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 130 mm bore the 33026U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 415 kN C level.", "The thin 55 mm section of 33026U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 130 mm bore smears the roller ends against the rib.", "ISO 355 makes the 130×200 mm envelope interchangeable but not the ratings: NTN prints 415/660 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 130 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33026U by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 415/660 kN ratings and 69.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33026U (ISO 355 2FE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33026U?", "a": "33026U is a metric 4T tapered roller bearing to ISO 355: 130 mm bore, 200 mm outside diameter and 55 mm assembled width T (5.118 × 7.874 × 2.165 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 415 kN, C0 660 kN, Pu 69.5 kN, grease limiting speed 1,700 r/min, oil speed 2,300 r/min, mass about 6090 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33026U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33026U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33026U designation encode the 130 mm bore and what is 2FE?", "a": "last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table). The 200 mm OD and 55 mm assembled T follow the ISO 355 dimension-series plan. 2FE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33026U list two speeds, 1,700 and 2,300 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33026U at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33026U mean?", "a": "Suffix reading on 33026U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33026U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2fe", "33026u", "33026U" ], "locale_variants": {} }, { "sku": "30226U", "brand": "NTN", "manufacturer_designation": "NTN 30226U", "series": "30200-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 230, "B_mm": 43.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 415, "static_load_kN": 505, "fatigue_load_limit_kN": 51.5, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 7050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 130 mm shaft with a thrust component, NTN lists 30226U, a metric 4T tapered roller bearing of 415 kN C and 505 kN C0 inside the 230 mm OD, 43.75 mm-wide assembled set. The last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 43.75 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The printed contact-angle geometry gives the standard-section 30200 family its characteristic load split — at 415/505 kN (C/C0) the static rating is about 1.22× C, typical of tapered bearings proportioned for heavy combined duty. The 50.0 mm section height over the 130 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Fillet radii must clear the ring chamfers of the 230 mm cup and 130 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 130 mm bore the 30226U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 415 kN C level.", "The standard-section 30200 family at 130 mm bore (230×43.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,000 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 43.75 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ISO 355 makes the 130×230 mm envelope interchangeable but not the ratings: NTN prints 415/505 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Minimum load matters at high speed: an unloaded 30226U at a large fraction of 1,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 415/505 kN ratings and 51.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30226U (ISO 355 4FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30226U?", "a": "30226U is a metric 4T tapered roller bearing to ISO 355: 130 mm bore, 230 mm outside diameter and 43.75 mm assembled width T (5.118 × 9.055 × 1.722 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 415 kN, C0 505 kN, Pu 51.5 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 7050 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30226U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30226U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30226U designation encode the 130 mm bore and what is 4FB?", "a": "last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table). The 230 mm OD and 43.75 mm assembled T follow the ISO 355 dimension-series plan. 4FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30226U list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30226U at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30226U mean?", "a": "Suffix reading on 30226U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30226U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30226u", "4fb", "30226U" ], "locale_variants": {} }, { "sku": "32226U", "brand": "NTN", "manufacturer_designation": "NTN 32226U", "series": "32200-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 230, "B_mm": 67.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 585, "static_load_kN": 815, "fatigue_load_limit_kN": 83.5, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 11300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 130 mm shaft with a thrust component, NTN lists 32226U, a metric 4T tapered roller bearing of 585 kN C and 815 kN C0 inside the 230 mm OD, 67.75 mm-wide assembled set. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32226U by the metric ISO 355 number (ISO series abbreviation 4FD): 130 mm bore, 230 mm OD. NTN grades 4T metric bearings as open bearings without integral seals; at 130 mm bore the application supplies the seals and the grease fill or oil supply to the 4FD ISO 355 assembly. The fatigue load limit Pu printed for 32226U is 83.5 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Mount the 130 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32226U.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 130 mm bore the 32226U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 585 kN C level.", "The heavy-section 32200 family at 130 mm bore (230×67.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,000 r/min oil ceiling.", "Never fit the 130 mm cone by hammering the 230 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume in the 67.75 mm-wide set; over-greasing a paired bearing churning at the 2,000 r/min oil-band speed raises temperature and destroys the preload setting.", "The 50.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32226U or the ring will bottom out on the radius instead of the shoulder face.", "The 585/815 kN ratings and 83.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32226U (ISO 355 4FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32226U?", "a": "32226U is a metric 4T tapered roller bearing to ISO 355: 130 mm bore, 230 mm outside diameter and 67.75 mm assembled width T (5.118 × 9.055 × 2.667 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 585 kN, C0 815 kN, Pu 83.5 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 11300 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32226U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32226U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32226U designation encode the 130 mm bore and what is 4FD?", "a": "last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table). The 230 mm OD and 67.75 mm assembled T follow the ISO 355 dimension-series plan. 4FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32226U list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32226U at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32226U mean?", "a": "Suffix reading on 32226U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32226U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32226u", "4fd", "32226U" ], "locale_variants": {} }, { "sku": "30326UUTG", "brand": "NTN", "manufacturer_designation": "NTN 30326UUTG", "series": "30300-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 280, "B_mm": 63.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 830, "static_load_kN": 830, "fatigue_load_limit_kN": 81, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 2000, "weight_g": 17400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30326UUTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 130×280 mm ISO 355 envelope, with 63.75 mm overall assembled width T. Digit by digit, the bare number identifies the large-OD 30300 family with the steeper contact angle and a bore code resolving to 130 mm; 280 mm OD and 63.75 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. 2203E lists two speed ceilings for 30326UUTG: 1,400 r/min with grease lubrication (the limiting speed) and 2,000 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Catalogue mass of the 30326UUTG set is 17400 g (0.685 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. When pairing 30326UUTG with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 130 mm bore the 30326UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 830 kN C level.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 130 mm bore; do not swap to the lighter family without re-checking the 1,400 r/min grease limit and the thrust load split.", "Replacing one half of an adjusted pair without resetting end play negates the 63.75 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ISO 355 makes the 130×280 mm envelope interchangeable but not the ratings: NTN prints 830/830 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Grease packs must leave free volume in the 63.75 mm-wide set; over-greasing a paired bearing churning at the 2,000 r/min oil-band speed raises temperature and destroys the preload setting.", "The 830/830 kN ratings and 81 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30326UUTG (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30326UUTG?", "a": "30326UUTG is a metric 4T tapered roller bearing to ISO 355: 130 mm bore, 280 mm outside diameter and 63.75 mm assembled width T (5.118 × 11.024 × 2.51 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 830 kN, C0 830 kN, Pu 81 kN, grease limiting speed 1,400 r/min, oil speed 2,000 r/min, mass about 17400 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30326UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30326UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30326UUTG designation encode the 130 mm bore and what is 2GB?", "a": "last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table). The 280 mm OD and 63.75 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30326UUTG list two speeds, 1,400 and 2,000 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30326UUTG at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30326UUTG mean?", "a": "Suffix reading on 30326UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30326UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30326uutg", "＊30326uutg", "30326UUTG" ], "locale_variants": {} }, { "sku": "31326XU", "brand": "NTN", "manufacturer_designation": "NTN 31326XU", "series": "31300-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 280, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 670, "static_load_kN": 780, "fatigue_load_limit_kN": 77, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1800, "weight_g": 19000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 31326XU in the steep-angle 31300 family for high axial load share: 130 mm bore, 280 mm cup OD, 72 mm T, with a grease limiting speed of 1,400 r/min and an oil-lubricated ceiling of 1,800 r/min. Digit by digit, the bare number identifies the steep-angle 31300 family for high axial load share and a bore code resolving to 130 mm; 280 mm OD and 72 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. Individually mounted, 31326XU takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Catalogue mass of the 31326XU set is 19000 g (0.748 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Open 4T bearings need application seals; without them the grease at the cone rib of 31326XU washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 130 mm bore the 31326XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 670 kN C level.", "The steeper contact angle of the steep-angle 31300 family for high axial load share raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 130 mm bore; do not swap to the lighter family without re-checking the 1,400 r/min grease limit and the thrust load split.", "Do not confuse T (72 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Do not confuse T (72 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Never fit the 130 mm cone by hammering the 280 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 670/780 kN ratings and 77 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 31326XU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 31326XU?", "a": "31326XU is a metric 4T tapered roller bearing to ISO 355: 130 mm bore, 280 mm outside diameter and 72 mm assembled width T (5.118 × 11.024 × 2.835 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 670 kN, C0 780 kN, Pu 77 kN, grease limiting speed 1,400 r/min, oil speed 1,800 r/min, mass about 19000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 31326XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (31326XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 31326XU designation encode the 130 mm bore and what is 7GB?", "a": "last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table). The 280 mm OD and 72 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 31326XU list two speeds, 1,400 and 1,800 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 31326XU at 1,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 31326XU mean?", "a": "Suffix reading on 31326XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "31326XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "31326xu", "7gb", "31326XU" ], "locale_variants": {} }, { "sku": "32326UTG", "brand": "NTN", "manufacturer_designation": "NTN 32326UTG", "series": "32300-series", "type": "tapered_roller", "d_mm": 130, "D_mm": 280, "B_mm": 98.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1140, "static_load_kN": 1240, "fatigue_load_limit_kN": 122, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 2000, "weight_g": 27400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32326UTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 130×280 mm ISO 355 envelope, with 98.75 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 130×280 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. At 1140 kN C the bearing offers about 8.8 kN of dynamic capacity per millimetre of the 130 mm bore — compare any substitution on this ratio and the 98.75 mm assembled T, not on bore alone. The 8.8 kN-per-mm-bore capacity figure for 32326UTG summarises the 1140 kN rating over 130 mm bore; use it to sanity-check an interchange candidate before swapping brands. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32326UTG arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 130 mm bore the 32326UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1140 kN C level.", "The extra-heavy 32300 family at 130 mm bore (280×98.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,000 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 130 mm shoulder geometry, because retrofitting flips the cups.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32326UTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "Open 32326UTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 1140/1240 kN ratings and 122 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32326UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32326UTG?", "a": "32326UTG is a metric 4T tapered roller bearing to ISO 355: 130 mm bore, 280 mm outside diameter and 98.75 mm assembled width T (5.118 × 11.024 × 3.888 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1140 kN, C0 1240 kN, Pu 122 kN, grease limiting speed 1,400 r/min, oil speed 2,000 r/min, mass about 27400 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32326UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32326UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32326UTG designation encode the 130 mm bore?", "a": "last two digits 26 are the ISO bore code, ×5 = 130 mm (codes 00–03 use the 10/12/15/17 exception table). The 280 mm OD and 98.75 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32326UTG list two speeds, 1,400 and 2,000 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32326UTG at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32326UTG mean?", "a": "Suffix reading on 32326UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32326UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32326utg", "＊32326utg", "32326UTG" ], "locale_variants": {} }, { "sku": "32928XU", "brand": "NTN", "manufacturer_designation": "NTN 32928XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 190, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 221, "static_load_kN": 375, "fatigue_load_limit_kN": 39, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 2500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32928XU is the NTN 4T catalogue entry for a 140×190×32 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32928XU resolves to 140 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Suffix reading on 32928XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. The 25.0 mm section height over the 140 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32928XU arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 140 mm bore the 32928XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 221 kN C level.", "The thin 32 mm section of 32928XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 140 mm bore smears the roller ends against the rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 140 mm shoulder geometry, because retrofitting flips the cups.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 140 mm shoulder geometry, because retrofitting flips the cups.", "ISO 355 makes the 140×190 mm envelope interchangeable but not the ratings: NTN prints 221/375 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 221/375 kN ratings and 39 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32928XU (ISO 355 2CC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32928XU?", "a": "32928XU is a metric 4T tapered roller bearing to ISO 355: 140 mm bore, 190 mm outside diameter and 32 mm assembled width T (5.512 × 7.48 × 1.26 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 221 kN, C0 375 kN, Pu 39 kN, grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 2500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32928XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32928XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32928XU designation encode the 140 mm bore and what is 2CC?", "a": "last two digits 28 are the ISO bore code, ×5 = 140 mm (codes 00–03 use the 10/12/15/17 exception table). The 190 mm OD and 32 mm assembled T follow the ISO 355 dimension-series plan. 2CC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32928XU list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32928XU at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32928XU mean?", "a": "Suffix reading on 32928XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32928XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2cc", "32928xu", "32928XU" ], "locale_variants": {} }, { "sku": "T4CB140", "brand": "NTN", "manufacturer_designation": "NTN T4CB140", "series": "T4CB-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 195, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 208, "static_load_kN": 299, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 2350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number T4CB140 denotes the large-size ISO 355 tapered-roller family of metric tapered roller bearings, 140 mm bore, 195 mm outside diameter and 29 mm assembled width T (5.512 × 7.677 × 1.142 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4CB, which is the maker-neutral cross-reference for the 140×195 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The 27.5 mm radial section carries the roller complement across the 140–195 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Catalogue mass of the T4CB140 set is 2350 g (0.093 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Fillet radii must clear the ring chamfers of the 195 mm cup and 140 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 140 mm bore the T4CB140 set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 208 kN C level.", "The large-size ISO 355 tapered-roller family at 140 mm bore (195×29 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,200 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 29 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 140 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering T4CB140 by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 208/299 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for T4CB140 (ISO 355 4CB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN T4CB140?", "a": "T4CB140 is a metric 4T tapered roller bearing to ISO 355: 140 mm bore, 195 mm outside diameter and 29 mm assembled width T (5.512 × 7.677 × 1.142 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 208 kN, C0 299 kN (2203E prints no Pu for this size), grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 2350 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on T4CB140?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (T4CB140); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the T4CB140 designation encode the 140 mm bore and what is 4CB?", "a": "trailing dimension block 140 prints the 140 mm bore directly for this large-size T-code. The 195 mm OD and 29 mm assembled T follow the ISO 355 dimension-series plan. 4CB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does T4CB140 list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates T4CB140 at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on T4CB140 mean?", "a": "The T2/T4/T7-style code is NTN's large-size tapered roller designation within ISO 355; it identifies the dimension series and 140 mm bore directly, and remains an open 4T execution ordered under its own code." } ], "cross_ref": [ { "equiv_sku": "T4CB140", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4cb", "4t-t4cb140", "t4cb140", "T4CB140" ], "locale_variants": {} }, { "sku": "32028XU", "brand": "NTN", "manufacturer_designation": "NTN 32028XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 210, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 365, "static_load_kN": 580, "fatigue_load_limit_kN": 60, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2100, "weight_g": 5320, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32028XU is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 140×210 mm ISO 355 envelope, with 45 mm overall assembled width T. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32028XU resolves to 140 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The printed contact-angle geometry gives the low-section 32000 family tuned for low friction its characteristic load split — at 365/580 kN (C/C0) the static rating is about 1.59× C, typical of tapered bearings proportioned for heavy combined duty. The fatigue load limit Pu printed for 32028XU is 60 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Fillet radii must clear the ring chamfers of the 210 mm cup and 140 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 140 mm bore the 32028XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 365 kN C level.", "The thin 45 mm section of 32028XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 140 mm bore smears the roller ends against the rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 140 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 140 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Minimum load matters at high speed: an unloaded 32028XU at a large fraction of 1,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 365/580 kN ratings and 60 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32028XU (ISO 355 4DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32028XU?", "a": "32028XU is a metric 4T tapered roller bearing to ISO 355: 140 mm bore, 210 mm outside diameter and 45 mm assembled width T (5.512 × 8.268 × 1.772 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 365 kN, C0 580 kN, Pu 60 kN, grease limiting speed 1,600 r/min, oil speed 2,100 r/min, mass about 5320 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32028XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32028XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32028XU designation encode the 140 mm bore and what is 4DC?", "a": "last two digits 28 are the ISO bore code, ×5 = 140 mm (codes 00–03 use the 10/12/15/17 exception table). The 210 mm OD and 45 mm assembled T follow the ISO 355 dimension-series plan. 4DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32028XU list two speeds, 1,600 and 2,100 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32028XU at 2,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32028XU mean?", "a": "Suffix reading on 32028XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32028XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32028xu", "4dc", "32028XU" ], "locale_variants": {} }, { "sku": "33028U", "brand": "NTN", "manufacturer_designation": "NTN 33028U", "series": "33000-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 210, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 435, "static_load_kN": 715, "fatigue_load_limit_kN": 74, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2100, "weight_g": 6590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "33028U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 140×210 mm ISO 355 envelope, with 56 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 33028U by the metric ISO 355 number (ISO series abbreviation 2DE): 140 mm bore, 210 mm OD. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 33028U cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Imperial cross-check for the drawing: 140×210×56 mm is 5.512 × 8.268 × 2.205 in; ISO 355 makes the envelope interchangeable but C/C0, 435/715 kN, is NTN-specific. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 33028U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 140 mm bore the 33028U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 435 kN C level.", "The thin 56 mm section of 33028U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 140 mm bore smears the roller ends against the rib.", "Grease packs must leave free volume in the 56 mm-wide set; over-greasing a paired bearing churning at the 2,100 r/min oil-band speed raises temperature and destroys the preload setting.", "Grease packs must leave free volume in the 56 mm-wide set; over-greasing a paired bearing churning at the 2,100 r/min oil-band speed raises temperature and destroys the preload setting.", "Do not confuse T (56 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 435/715 kN ratings and 74 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33028U (ISO 355 2DE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 33028U?", "a": "33028U is a metric 4T tapered roller bearing to ISO 355: 140 mm bore, 210 mm outside diameter and 56 mm assembled width T (5.512 × 8.268 × 2.205 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 435 kN, C0 715 kN, Pu 74 kN, grease limiting speed 1,600 r/min, oil speed 2,100 r/min, mass about 6590 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 33028U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (33028U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 33028U designation encode the 140 mm bore and what is 2DE?", "a": "last two digits 28 are the ISO bore code, ×5 = 140 mm (codes 00–03 use the 10/12/15/17 exception table). The 210 mm OD and 56 mm assembled T follow the ISO 355 dimension-series plan. 2DE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 33028U list two speeds, 1,600 and 2,100 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33028U at 2,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 33028U mean?", "a": "Suffix reading on 33028U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "33028U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2de", "33028u", "33028U" ], "locale_variants": {} }, { "sku": "30228U", "brand": "NTN", "manufacturer_designation": "NTN 30228U", "series": "30200-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 250, "B_mm": 45.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 465, "static_load_kN": 570, "fatigue_load_limit_kN": 57, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1900, "weight_g": 8730, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30228U in the standard-section 30200 family: 140 mm bore, 250 mm cup OD, 45.75 mm T, with a grease limiting speed of 1,400 r/min and an oil-lubricated ceiling of 1,900 r/min. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30228U by the metric ISO 355 number (ISO series abbreviation 4FB): 140 mm bore, 250 mm OD. At 465 kN C the bearing offers about 3.3 kN of dynamic capacity per millimetre of the 140 mm bore — compare any substitution on this ratio and the 45.75 mm assembled T, not on bore alone. The 3.3 kN-per-mm-bore capacity figure for 30228U summarises the 465 kN rating over 140 mm bore; use it to sanity-check an interchange candidate before swapping brands. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 30228U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 140 mm bore the 30228U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 465 kN C level.", "The standard-section 30200 family at 140 mm bore (250×45.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,900 r/min oil ceiling.", "The 55.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30228U or the ring will bottom out on the radius instead of the shoulder face.", "Replacing one half of an adjusted pair without resetting end play negates the 45.75 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 30228U units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 465/570 kN ratings and 57 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30228U (ISO 355 4FB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30228U?", "a": "30228U is a metric 4T tapered roller bearing to ISO 355: 140 mm bore, 250 mm outside diameter and 45.75 mm assembled width T (5.512 × 9.843 × 1.801 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 465 kN, C0 570 kN, Pu 57 kN, grease limiting speed 1,400 r/min, oil speed 1,900 r/min, mass about 8730 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30228U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30228U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30228U designation encode the 140 mm bore and what is 4FB?", "a": "last two digits 28 are the ISO bore code, ×5 = 140 mm (codes 00–03 use the 10/12/15/17 exception table). The 250 mm OD and 45.75 mm assembled T follow the ISO 355 dimension-series plan. 4FB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30228U list two speeds, 1,400 and 1,900 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30228U at 1,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30228U mean?", "a": "Suffix reading on 30228U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30228U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30228u", "4fb", "30228U" ], "locale_variants": {} }, { "sku": "32228U", "brand": "NTN", "manufacturer_designation": "NTN 32228U", "series": "32200-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 250, "B_mm": 71.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 675, "static_load_kN": 920, "fatigue_load_limit_kN": 92, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1900, "weight_g": 14200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32228U in the heavy-section 32200 family: 140 mm bore, 250 mm cup OD, 71.75 mm T, with a grease limiting speed of 1,400 r/min and an oil-lubricated ceiling of 1,900 r/min. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32228U resolves to 140 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. The 55.0 mm section height over the 140 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Fillet radii must clear the ring chamfers of the 250 mm cup and 140 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 140 mm bore the 32228U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 675 kN C level.", "The heavy-section 32200 family at 140 mm bore (250×71.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,900 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 140 mm shoulder geometry, because retrofitting flips the cups.", "The 55.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32228U or the ring will bottom out on the radius instead of the shoulder face.", "Replacing one half of an adjusted pair without resetting end play negates the 71.75 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 675/920 kN ratings and 92 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32228U (ISO 355 4FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32228U?", "a": "32228U is a metric 4T tapered roller bearing to ISO 355: 140 mm bore, 250 mm outside diameter and 71.75 mm assembled width T (5.512 × 9.843 × 2.825 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 675 kN, C0 920 kN, Pu 92 kN, grease limiting speed 1,400 r/min, oil speed 1,900 r/min, mass about 14200 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32228U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32228U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32228U designation encode the 140 mm bore and what is 4FD?", "a": "last two digits 28 are the ISO bore code, ×5 = 140 mm (codes 00–03 use the 10/12/15/17 exception table). The 250 mm OD and 71.75 mm assembled T follow the ISO 355 dimension-series plan. 4FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32228U list two speeds, 1,400 and 1,900 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32228U at 1,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32228U mean?", "a": "Suffix reading on 32228U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32228U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32228u", "4fd", "32228U" ], "locale_variants": {} }, { "sku": "30328UUTG", "brand": "NTN", "manufacturer_designation": "NTN 30328UUTG", "series": "30300-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 300, "B_mm": 67.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 945, "static_load_kN": 950, "fatigue_load_limit_kN": 91.5, "limiting_speed_rpm": 1300, "max_rpm": 1300, "speed_oil_rpm": 1800, "weight_g": 21100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30328UUTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 140×300 mm ISO 355 envelope, with 67.75 mm overall assembled width T. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30328UUTG resolves to 140 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The printed contact-angle geometry gives the large-OD 30300 family with the steeper contact angle its characteristic load split — at 945/950 kN (C/C0) the static rating is about 1.01× C, typical of tapered bearings proportioned for heavy combined duty. Catalogue mass of the 30328UUTG set is 21100 g (0.831 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Open 4T bearings need application seals; without them the grease at the cone rib of 30328UUTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 140 mm bore the 30328UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 945 kN C level.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 140 mm bore; do not swap to the lighter family without re-checking the 1,300 r/min grease limit and the thrust load split.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 140 mm shoulder geometry, because retrofitting flips the cups.", "Grease packs must leave free volume in the 67.75 mm-wide set; over-greasing a paired bearing churning at the 1,800 r/min oil-band speed raises temperature and destroys the preload setting.", "Minimum load matters at high speed: an unloaded 30328UUTG at a large fraction of 1,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 945/950 kN ratings and 91.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30328UUTG (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30328UUTG?", "a": "30328UUTG is a metric 4T tapered roller bearing to ISO 355: 140 mm bore, 300 mm outside diameter and 67.75 mm assembled width T (5.512 × 11.811 × 2.667 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 945 kN, C0 950 kN, Pu 91.5 kN, grease limiting speed 1,300 r/min, oil speed 1,800 r/min, mass about 21100 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30328UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30328UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30328UUTG designation encode the 140 mm bore and what is 2GB?", "a": "last two digits 28 are the ISO bore code, ×5 = 140 mm (codes 00–03 use the 10/12/15/17 exception table). The 300 mm OD and 67.75 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30328UUTG list two speeds, 1,300 and 1,800 r/min?", "a": "The lower figure, 1,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30328UUTG at 1,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30328UUTG mean?", "a": "Suffix reading on 30328UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30328UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30328uutg", "＊30328uutg", "30328UUTG" ], "locale_variants": {} }, { "sku": "31328XU", "brand": "NTN", "manufacturer_designation": "NTN 31328XU", "series": "31300-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 300, "B_mm": 77, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 760, "static_load_kN": 905, "fatigue_load_limit_kN": 87, "limiting_speed_rpm": 1300, "max_rpm": 1300, "speed_oil_rpm": 1700, "weight_g": 22900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 31328XU denotes the steep-angle 31300 family for high axial load share of metric tapered roller bearings, 140 mm bore, 300 mm outside diameter and 77 mm assembled width T (5.512 × 11.811 × 3.031 in) to the ISO 355 boundary plan. The last two digits 28 are the ISO bore code, ×5 = 140 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 77 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 31328XU cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Speed planning uses both catalogue columns: grease 1,300 r/min is the cage/rib mechanical ceiling for 31328XU, oil 1,700 r/min is available with circulating oil — a 400 r/min margin at this size. Fillet radii must clear the ring chamfers of the 300 mm cup and 140 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 140 mm bore the 31328XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 760 kN C level.", "The steeper contact angle of the steep-angle 31300 family for high axial load share raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 140 mm bore; do not swap to the lighter family without re-checking the 1,300 r/min grease limit and the thrust load split.", "Open 31328XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,300 r/min grease figure is meaningless once water reaches the cone rib.", "Minimum load matters at high speed: an unloaded 31328XU at a large fraction of 1,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Do not confuse T (77 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 760/905 kN ratings and 87 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 31328XU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 31328XU?", "a": "31328XU is a metric 4T tapered roller bearing to ISO 355: 140 mm bore, 300 mm outside diameter and 77 mm assembled width T (5.512 × 11.811 × 3.031 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 760 kN, C0 905 kN, Pu 87 kN, grease limiting speed 1,300 r/min, oil speed 1,700 r/min, mass about 22900 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 31328XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (31328XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 31328XU designation encode the 140 mm bore and what is 7GB?", "a": "last two digits 28 are the ISO bore code, ×5 = 140 mm (codes 00–03 use the 10/12/15/17 exception table). The 300 mm OD and 77 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 31328XU list two speeds, 1,300 and 1,700 r/min?", "a": "The lower figure, 1,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 31328XU at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 31328XU mean?", "a": "Suffix reading on 31328XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "31328XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "31328xu", "7gb", "31328XU" ], "locale_variants": {} }, { "sku": "32328UTG", "brand": "NTN", "manufacturer_designation": "NTN 32328UTG", "series": "32300-series", "type": "tapered_roller", "d_mm": 140, "D_mm": 300, "B_mm": 107.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1270, "static_load_kN": 1370, "fatigue_load_limit_kN": 132, "limiting_speed_rpm": 1300, "max_rpm": 1300, "speed_oil_rpm": 1800, "weight_g": 33500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32328UTG is the NTN 4T catalogue entry for a 140×300×107.75 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Digit by digit, the bare number identifies the extra-heavy 32300 family and a bore code resolving to 140 mm; 300 mm OD and 107.75 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. At 1270 kN C the bearing offers about 9.1 kN of dynamic capacity per millimetre of the 140 mm bore — compare any substitution on this ratio and the 107.75 mm assembled T, not on bore alone. The fatigue load limit Pu printed for 32328UTG is 132 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Open 4T bearings need application seals; without them the grease at the cone rib of 32328UTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 140 mm bore the 32328UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1270 kN C level.", "The extra-heavy 32300 family at 140 mm bore (300×107.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,800 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 32328UTG at a large fraction of 1,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Do not confuse T (107.75 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Open 32328UTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,300 r/min grease figure is meaningless once water reaches the cone rib.", "The 1270/1370 kN ratings and 132 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32328UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32328UTG?", "a": "32328UTG is a metric 4T tapered roller bearing to ISO 355: 140 mm bore, 300 mm outside diameter and 107.75 mm assembled width T (5.512 × 11.811 × 4.242 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1270 kN, C0 1370 kN, Pu 132 kN, grease limiting speed 1,300 r/min, oil speed 1,800 r/min, mass about 33500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32328UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32328UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32328UTG designation encode the 140 mm bore?", "a": "last two digits 28 are the ISO bore code, ×5 = 140 mm (codes 00–03 use the 10/12/15/17 exception table). The 300 mm OD and 107.75 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32328UTG list two speeds, 1,300 and 1,800 r/min?", "a": "The lower figure, 1,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32328UTG at 1,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32328UTG mean?", "a": "Suffix reading on 32328UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32328UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=171", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32328utg", "＊32328utg", "32328UTG" ], "locale_variants": {} }, { "sku": "32930XU", "brand": "NTN", "manufacturer_designation": "NTN 32930XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 150, "D_mm": 210, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 297, "static_load_kN": 490, "fatigue_load_limit_kN": 50, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2100, "weight_g": 3930, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32930XU in the extra-light thin-section 32900 family: 150 mm bore, 210 mm cup OD, 38 mm T, with a grease limiting speed of 1,600 r/min and an oil-lubricated ceiling of 2,100 r/min. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32930XU resolves to 150 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. 2203E lists two speed ceilings for 32930XU: 1,600 r/min with grease lubrication (the limiting speed) and 2,100 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Selection: C 297 kN against C0 490 kN gives a C0/C ratio of 1.65 for the 150 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 32930XU washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 150 mm bore the 32930XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 297 kN C level.", "The thin 38 mm section of 32930XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 150 mm bore smears the roller ends against the rib.", "Open 32930XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,600 r/min grease figure is meaningless once water reaches the cone rib.", "Open 32930XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,600 r/min grease figure is meaningless once water reaches the cone rib.", "Grease packs must leave free volume in the 38 mm-wide set; over-greasing a paired bearing churning at the 2,100 r/min oil-band speed raises temperature and destroys the preload setting.", "The 297/490 kN ratings and 50 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32930XU (ISO 355 2DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32930XU?", "a": "32930XU is a metric 4T tapered roller bearing to ISO 355: 150 mm bore, 210 mm outside diameter and 38 mm assembled width T (5.906 × 8.268 × 1.496 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 297 kN, C0 490 kN, Pu 50 kN, grease limiting speed 1,600 r/min, oil speed 2,100 r/min, mass about 3930 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32930XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32930XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32930XU designation encode the 150 mm bore and what is 2DC?", "a": "last two digits 30 are the ISO bore code, ×5 = 150 mm (codes 00–03 use the 10/12/15/17 exception table). The 210 mm OD and 38 mm assembled T follow the ISO 355 dimension-series plan. 2DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32930XU list two speeds, 1,600 and 2,100 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32930XU at 2,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32930XU mean?", "a": "Suffix reading on 32930XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32930XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2dc", "32930xu", "32930XU" ], "locale_variants": {} }, { "sku": "32030XU", "brand": "NTN", "manufacturer_designation": "NTN 32030XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 150, "D_mm": 225, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 410, "static_load_kN": 655, "fatigue_load_limit_kN": 66, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1900, "weight_g": 6450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32030XU is the NTN 4T catalogue entry for a 150×225×48 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32030XU resolves to 150 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32030XU, since running clearance is set during assembly. The two speed columns differ by a factor of .74 (grease/limiting 1,400 vs oil 1,900 r/min); heat generation at the cone rib decides which lubrication a real 32030XU arrangement can sustain. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 32030XU; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 150 mm bore the 32030XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 410 kN C level.", "The thin 48 mm section of 32030XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 150 mm bore smears the roller ends against the rib.", "Minimum load matters at high speed: an unloaded 32030XU at a large fraction of 1,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 37.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32030XU or the ring will bottom out on the radius instead of the shoulder face.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 150 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 410/655 kN ratings and 66 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32030XU (ISO 355 4EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32030XU?", "a": "32030XU is a metric 4T tapered roller bearing to ISO 355: 150 mm bore, 225 mm outside diameter and 48 mm assembled width T (5.906 × 8.858 × 1.89 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 410 kN, C0 655 kN, Pu 66 kN, grease limiting speed 1,400 r/min, oil speed 1,900 r/min, mass about 6450 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32030XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32030XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32030XU designation encode the 150 mm bore and what is 4EC?", "a": "last two digits 30 are the ISO bore code, ×5 = 150 mm (codes 00–03 use the 10/12/15/17 exception table). The 225 mm OD and 48 mm assembled T follow the ISO 355 dimension-series plan. 4EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32030XU list two speeds, 1,400 and 1,900 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32030XU at 1,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32030XU mean?", "a": "Suffix reading on 32030XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32030XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32030xu", "4ec", "32030XU" ], "locale_variants": {} }, { "sku": "30230U", "brand": "NTN", "manufacturer_designation": "NTN 30230U", "series": "30200-series", "type": "tapered_roller", "d_mm": 150, "D_mm": 270, "B_mm": 49, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 500, "static_load_kN": 605, "fatigue_load_limit_kN": 59, "limiting_speed_rpm": 1300, "max_rpm": 1300, "speed_oil_rpm": 1700, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30230U is the NTN 4T catalogue entry for a 150×270×49 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. The last two digits 30 are the ISO bore code, ×5 = 150 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 49 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 30230U, not only the raceway. The two speed columns differ by a factor of .76 (grease/limiting 1,300 vs oil 1,700 r/min); heat generation at the cone rib decides which lubrication a real 30230U arrangement can sustain. Open 4T bearings need application seals; without them the grease at the cone rib of 30230U washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 150 mm bore the 30230U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 500 kN C level.", "The standard-section 30200 family at 150 mm bore (270×49 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,700 r/min oil ceiling.", "Open 30230U units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,300 r/min grease figure is meaningless once water reaches the cone rib.", "Never fit the 150 mm cone by hammering the 270 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 150 mm shoulder geometry, because retrofitting flips the cups.", "The 500/605 kN ratings and 59 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30230U (ISO 355 4GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30230U?", "a": "30230U is a metric 4T tapered roller bearing to ISO 355: 150 mm bore, 270 mm outside diameter and 49 mm assembled width T (5.906 × 10.63 × 1.929 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 500 kN, C0 605 kN, Pu 59 kN, grease limiting speed 1,300 r/min, oil speed 1,700 r/min, mass about 11000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30230U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30230U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30230U designation encode the 150 mm bore and what is 4GB?", "a": "last two digits 30 are the ISO bore code, ×5 = 150 mm (codes 00–03 use the 10/12/15/17 exception table). The 270 mm OD and 49 mm assembled T follow the ISO 355 dimension-series plan. 4GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30230U list two speeds, 1,300 and 1,700 r/min?", "a": "The lower figure, 1,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30230U at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30230U mean?", "a": "Suffix reading on 30230U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30230U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30230u", "4gb", "30230U" ], "locale_variants": {} }, { "sku": "32230U", "brand": "NTN", "manufacturer_designation": "NTN 32230U", "series": "32200-series", "type": "tapered_roller", "d_mm": 150, "D_mm": 270, "B_mm": 77, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 775, "static_load_kN": 1070, "fatigue_load_limit_kN": 105, "limiting_speed_rpm": 1300, "max_rpm": 1300, "speed_oil_rpm": 1700, "weight_g": 18000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32230U is the NTN 4T catalogue entry for a 150×270×77 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4GD, which is the maker-neutral cross-reference for the 150×270 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32230U cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The two speed columns differ by a factor of .76 (grease/limiting 1,300 vs oil 1,700 r/min); heat generation at the cone rib decides which lubrication a real 32230U arrangement can sustain. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 32230U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 150 mm bore the 32230U set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 775 kN C level.", "The heavy-section 32200 family at 150 mm bore (270×77 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,700 r/min oil ceiling.", "The 60.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32230U or the ring will bottom out on the radius instead of the shoulder face.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 150 mm shoulder geometry, because retrofitting flips the cups.", "Do not confuse T (77 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 775/1070 kN ratings and 105 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32230U (ISO 355 4GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32230U?", "a": "32230U is a metric 4T tapered roller bearing to ISO 355: 150 mm bore, 270 mm outside diameter and 77 mm assembled width T (5.906 × 10.63 × 3.031 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 775 kN, C0 1070 kN, Pu 105 kN, grease limiting speed 1,300 r/min, oil speed 1,700 r/min, mass about 18000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32230U?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32230U); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32230U designation encode the 150 mm bore and what is 4GD?", "a": "last two digits 30 are the ISO bore code, ×5 = 150 mm (codes 00–03 use the 10/12/15/17 exception table). The 270 mm OD and 77 mm assembled T follow the ISO 355 dimension-series plan. 4GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32230U list two speeds, 1,300 and 1,700 r/min?", "a": "The lower figure, 1,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32230U at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32230U mean?", "a": "Suffix reading on 32230U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32230U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32230u", "4gd", "32230U" ], "locale_variants": {} }, { "sku": "30330UUTG", "brand": "NTN", "manufacturer_designation": "NTN 30330UUTG", "series": "30300-series", "type": "tapered_roller", "d_mm": 150, "D_mm": 320, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1060, "static_load_kN": 1070, "fatigue_load_limit_kN": 101, "limiting_speed_rpm": 1200, "max_rpm": 1200, "speed_oil_rpm": 1700, "weight_g": 25400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 150 mm shaft with a thrust component, NTN lists 30330UUTG, a metric 4T tapered roller bearing of 1060 kN C and 1070 kN C0 inside the 320 mm OD, 72 mm-wide assembled set. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30330UUTG by the metric ISO 355 number (ISO series abbreviation 2GB): 150 mm bore, 320 mm OD. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 30330UUTG, since running clearance is set during assembly. The two speed columns differ by a factor of .71 (grease/limiting 1,200 vs oil 1,700 r/min); heat generation at the cone rib decides which lubrication a real 30330UUTG arrangement can sustain. Mount the 150 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30330UUTG.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 150 mm bore the 30330UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1060 kN C level.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 150 mm bore; do not swap to the lighter family without re-checking the 1,200 r/min grease limit and the thrust load split.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 150 mm shoulder geometry, because retrofitting flips the cups.", "ISO 355 makes the 150×320 mm envelope interchangeable but not the ratings: NTN prints 1060/1070 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 150 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 1060/1070 kN ratings and 101 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30330UUTG (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30330UUTG?", "a": "30330UUTG is a metric 4T tapered roller bearing to ISO 355: 150 mm bore, 320 mm outside diameter and 72 mm assembled width T (5.906 × 12.598 × 2.835 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1060 kN, C0 1070 kN, Pu 101 kN, grease limiting speed 1,200 r/min, oil speed 1,700 r/min, mass about 25400 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30330UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30330UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30330UUTG designation encode the 150 mm bore and what is 2GB?", "a": "last two digits 30 are the ISO bore code, ×5 = 150 mm (codes 00–03 use the 10/12/15/17 exception table). The 320 mm OD and 72 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30330UUTG list two speeds, 1,200 and 1,700 r/min?", "a": "The lower figure, 1,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30330UUTG at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30330UUTG mean?", "a": "Suffix reading on 30330UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30330UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30330uutg", "＊30330uutg", "30330UUTG" ], "locale_variants": {} }, { "sku": "31330XU", "brand": "NTN", "manufacturer_designation": "NTN 31330XU", "series": "31300-series", "type": "tapered_roller", "d_mm": 150, "D_mm": 320, "B_mm": 82, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 860, "static_load_kN": 1030, "fatigue_load_limit_kN": 97.5, "limiting_speed_rpm": 1200, "max_rpm": 1200, "speed_oil_rpm": 1600, "weight_g": 27700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 31330XU in the steep-angle 31300 family for high axial load share: 150 mm bore, 320 mm cup OD, 82 mm T, with a grease limiting speed of 1,200 r/min and an oil-lubricated ceiling of 1,600 r/min. The last two digits 30 are the ISO bore code, ×5 = 150 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 82 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. At 860 kN C the bearing offers about 5.7 kN of dynamic capacity per millimetre of the 150 mm bore — compare any substitution on this ratio and the 82 mm assembled T, not on bore alone. The 5.7 kN-per-mm-bore capacity figure for 31330XU summarises the 860 kN rating over 150 mm bore; use it to sanity-check an interchange candidate before swapping brands. Mount the 150 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 31330XU.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 150 mm bore the 31330XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 860 kN C level.", "The steeper contact angle of the steep-angle 31300 family for high axial load share raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 150 mm bore; do not swap to the lighter family without re-checking the 1,200 r/min grease limit and the thrust load split.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 150 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Do not confuse T (82 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Open 31330XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,200 r/min grease figure is meaningless once water reaches the cone rib.", "The 860/1030 kN ratings and 97.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 31330XU (ISO 355 7GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 31330XU?", "a": "31330XU is a metric 4T tapered roller bearing to ISO 355: 150 mm bore, 320 mm outside diameter and 82 mm assembled width T (5.906 × 12.598 × 3.228 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 860 kN, C0 1030 kN, Pu 97.5 kN, grease limiting speed 1,200 r/min, oil speed 1,600 r/min, mass about 27700 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 31330XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (31330XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 31330XU designation encode the 150 mm bore and what is 7GB?", "a": "last two digits 30 are the ISO bore code, ×5 = 150 mm (codes 00–03 use the 10/12/15/17 exception table). The 320 mm OD and 82 mm assembled T follow the ISO 355 dimension-series plan. 7GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 31330XU list two speeds, 1,200 and 1,600 r/min?", "a": "The lower figure, 1,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 31330XU at 1,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 31330XU mean?", "a": "Suffix reading on 31330XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "31330XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "31330xu", "7gb", "31330XU" ], "locale_variants": {} }, { "sku": "32330UTG", "brand": "NTN", "manufacturer_designation": "NTN 32330UTG", "series": "32300-series", "type": "tapered_roller", "d_mm": 150, "D_mm": 320, "B_mm": 114, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1490, "static_load_kN": 1750, "fatigue_load_limit_kN": 166, "limiting_speed_rpm": 1200, "max_rpm": 1200, "speed_oil_rpm": 1700, "weight_g": 42100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32330UTG in the extra-heavy 32300 family: 150 mm bore, 320 mm cup OD, 114 mm T, with a grease limiting speed of 1,200 r/min and an oil-lubricated ceiling of 1,700 r/min. Digit by digit, the bare number identifies the extra-heavy 32300 family and a bore code resolving to 150 mm; 320 mm OD and 114 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32330UTG, since running clearance is set during assembly. The fatigue load limit Pu printed for 32330UTG is 166 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32330UTG arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 150 mm bore the 32330UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1490 kN C level.", "The extra-heavy 32300 family at 150 mm bore (320×114 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,700 r/min oil ceiling.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32330UTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32330UTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 150 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 1490/1750 kN ratings and 166 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32330UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32330UTG?", "a": "32330UTG is a metric 4T tapered roller bearing to ISO 355: 150 mm bore, 320 mm outside diameter and 114 mm assembled width T (5.906 × 12.598 × 4.488 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1490 kN, C0 1750 kN, Pu 166 kN, grease limiting speed 1,200 r/min, oil speed 1,700 r/min, mass about 42100 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32330UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32330UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32330UTG designation encode the 150 mm bore?", "a": "last two digits 30 are the ISO bore code, ×5 = 150 mm (codes 00–03 use the 10/12/15/17 exception table). The 320 mm OD and 114 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32330UTG list two speeds, 1,200 and 1,700 r/min?", "a": "The lower figure, 1,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32330UTG at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32330UTG mean?", "a": "Suffix reading on 32330UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32330UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32330utg", "＊32330utg", "32330UTG" ], "locale_variants": {} }, { "sku": "32932XU", "brand": "NTN", "manufacturer_designation": "NTN 32932XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 160, "D_mm": 220, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 305, "static_load_kN": 520, "fatigue_load_limit_kN": 52.5, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 1900, "weight_g": 4140, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32932XU denotes the extra-light thin-section 32900 family of metric tapered roller bearings, 160 mm bore, 220 mm outside diameter and 38 mm assembled width T (6.299 × 8.661 × 1.496 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 2DC, which is the maker-neutral cross-reference for the 160×220 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Imperial cross-check for the drawing: 160×220×38 mm is 6.299 × 8.661 × 1.496 in; ISO 355 makes the envelope interchangeable but C/C0, 305/520 kN, is NTN-specific. Fillet radii must clear the ring chamfers of the 220 mm cup and 160 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 160 mm bore the 32932XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 305 kN C level.", "The thin 38 mm section of 32932XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 160 mm bore smears the roller ends against the rib.", "Never fit the 160 mm cone by hammering the 220 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 160 mm shoulder geometry, because retrofitting flips the cups.", "Replacing one half of an adjusted pair without resetting end play negates the 38 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 305/520 kN ratings and 52.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32932XU (ISO 355 2DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32932XU?", "a": "32932XU is a metric 4T tapered roller bearing to ISO 355: 160 mm bore, 220 mm outside diameter and 38 mm assembled width T (6.299 × 8.661 × 1.496 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 305 kN, C0 520 kN, Pu 52.5 kN, grease limiting speed 1,500 r/min, oil speed 1,900 r/min, mass about 4140 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32932XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32932XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32932XU designation encode the 160 mm bore and what is 2DC?", "a": "last two digits 32 are the ISO bore code, ×5 = 160 mm (codes 00–03 use the 10/12/15/17 exception table). The 220 mm OD and 38 mm assembled T follow the ISO 355 dimension-series plan. 2DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32932XU list two speeds, 1,500 and 1,900 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32932XU at 1,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32932XU mean?", "a": "Suffix reading on 32932XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32932XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2dc", "32932xu", "32932XU" ], "locale_variants": {} }, { "sku": "32032XU", "brand": "NTN", "manufacturer_designation": "NTN 32032XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 160, "D_mm": 240, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 485, "static_load_kN": 790, "fatigue_load_limit_kN": 78.5, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1800, "weight_g": 7860, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32032XU is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 160×240 mm ISO 355 envelope, with 51 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32032XU by the metric ISO 355 number (ISO series abbreviation 4EC): 160 mm bore, 240 mm OD. Suffix reading on 32032XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles. The 40.0 mm section height over the 160 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Mount the 160 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32032XU.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 160 mm bore the 32032XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 485 kN C level.", "The thin 51 mm section of 32032XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 160 mm bore smears the roller ends against the rib.", "Never fit the 160 mm cone by hammering the 240 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32032XU by size alone can deliver the wrong contact-angle execution for a pinion position.", "ISO 355 makes the 160×240 mm envelope interchangeable but not the ratings: NTN prints 485/790 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 485/790 kN ratings and 78.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32032XU (ISO 355 4EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32032XU?", "a": "32032XU is a metric 4T tapered roller bearing to ISO 355: 160 mm bore, 240 mm outside diameter and 51 mm assembled width T (6.299 × 9.449 × 2.008 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 485 kN, C0 790 kN, Pu 78.5 kN, grease limiting speed 1,400 r/min, oil speed 1,800 r/min, mass about 7860 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32032XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32032XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32032XU designation encode the 160 mm bore and what is 4EC?", "a": "last two digits 32 are the ISO bore code, ×5 = 160 mm (codes 00–03 use the 10/12/15/17 exception table). The 240 mm OD and 51 mm assembled T follow the ISO 355 dimension-series plan. 4EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32032XU list two speeds, 1,400 and 1,800 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32032XU at 1,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32032XU mean?", "a": "Suffix reading on 32032XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32032XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32032xu", "4ec", "32032XU" ], "locale_variants": {} }, { "sku": "30232UUTG", "brand": "NTN", "manufacturer_designation": "NTN 30232UUTG", "series": "30200-series", "type": "tapered_roller", "d_mm": 160, "D_mm": 290, "B_mm": 52, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 675, "static_load_kN": 720, "fatigue_load_limit_kN": 68.5, "limiting_speed_rpm": 1200, "max_rpm": 1200, "speed_oil_rpm": 1700, "weight_g": 13400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30232UUTG belongs to the NTN metric 4T tapered roller range (standard-section 30200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30232UUTG by the metric ISO 355 number (ISO series abbreviation 4GB): 160 mm bore, 290 mm OD. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 30232UUTG, not only the raceway. The 65.0 mm section height over the 160 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Mount the 160 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30232UUTG.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 160 mm bore the 30232UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 675 kN C level.", "The standard-section 30200 family at 160 mm bore (290×52 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,700 r/min oil ceiling.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30232UUTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "Minimum load matters at high speed: an unloaded 30232UUTG at a large fraction of 1,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 160 mm shoulder geometry, because retrofitting flips the cups.", "The 675/720 kN ratings and 68.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30232UUTG (ISO 355 4GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30232UUTG?", "a": "30232UUTG is a metric 4T tapered roller bearing to ISO 355: 160 mm bore, 290 mm outside diameter and 52 mm assembled width T (6.299 × 11.417 × 2.047 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 675 kN, C0 720 kN, Pu 68.5 kN, grease limiting speed 1,200 r/min, oil speed 1,700 r/min, mass about 13400 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30232UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30232UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30232UUTG designation encode the 160 mm bore and what is 4GB?", "a": "last two digits 32 are the ISO bore code, ×5 = 160 mm (codes 00–03 use the 10/12/15/17 exception table). The 290 mm OD and 52 mm assembled T follow the ISO 355 dimension-series plan. 4GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30232UUTG list two speeds, 1,200 and 1,700 r/min?", "a": "The lower figure, 1,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30232UUTG at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30232UUTG mean?", "a": "Suffix reading on 30232UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30232UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30232uutg", "4gb", "＊30232uutg", "30232UUTG" ], "locale_variants": {} }, { "sku": "32232UUTG", "brand": "NTN", "manufacturer_designation": "NTN 32232UUTG", "series": "32200-series", "type": "tapered_roller", "d_mm": 160, "D_mm": 290, "B_mm": 84, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1140, "static_load_kN": 1420, "fatigue_load_limit_kN": 136, "limiting_speed_rpm": 1200, "max_rpm": 1200, "speed_oil_rpm": 1700, "weight_g": 23900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32232UUTG is the NTN 4T catalogue entry for a 160×290×84 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. The last two digits 32 are the ISO bore code, ×5 = 160 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 84 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. At 1140 kN C the bearing offers about 7.1 kN of dynamic capacity per millimetre of the 160 mm bore — compare any substitution on this ratio and the 84 mm assembled T, not on bore alone. Speed planning uses both catalogue columns: grease 1,200 r/min is the cage/rib mechanical ceiling for 32232UUTG, oil 1,700 r/min is available with circulating oil — a 500 r/min margin at this size. When pairing 32232UUTG with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 160 mm bore the 32232UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1140 kN C level.", "The heavy-section 32200 family at 160 mm bore (290×84 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,700 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 160 mm shoulder geometry, because retrofitting flips the cups.", "The 65.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32232UUTG or the ring will bottom out on the radius instead of the shoulder face.", "Open 32232UUTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,200 r/min grease figure is meaningless once water reaches the cone rib.", "The 1140/1420 kN ratings and 136 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32232UUTG (ISO 355 4GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32232UUTG?", "a": "32232UUTG is a metric 4T tapered roller bearing to ISO 355: 160 mm bore, 290 mm outside diameter and 84 mm assembled width T (6.299 × 11.417 × 3.307 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1140 kN, C0 1420 kN, Pu 136 kN, grease limiting speed 1,200 r/min, oil speed 1,700 r/min, mass about 23900 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32232UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32232UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32232UUTG designation encode the 160 mm bore and what is 4GD?", "a": "last two digits 32 are the ISO bore code, ×5 = 160 mm (codes 00–03 use the 10/12/15/17 exception table). The 290 mm OD and 84 mm assembled T follow the ISO 355 dimension-series plan. 4GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32232UUTG list two speeds, 1,200 and 1,700 r/min?", "a": "The lower figure, 1,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32232UUTG at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32232UUTG mean?", "a": "Suffix reading on 32232UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32232UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32232uutg", "4gd", "＊32232uutg", "32232UUTG" ], "locale_variants": {} }, { "sku": "30332UUTG", "brand": "NTN", "manufacturer_designation": "NTN 30332UUTG", "series": "30300-series", "type": "tapered_roller", "d_mm": 160, "D_mm": 340, "B_mm": 75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1170, "static_load_kN": 1200, "fatigue_load_limit_kN": 110, "limiting_speed_rpm": 1100, "max_rpm": 1100, "speed_oil_rpm": 1600, "weight_g": 29800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 160 mm shaft with a thrust component, NTN lists 30332UUTG, a metric 4T tapered roller bearing of 1170 kN C and 1200 kN C0 inside the 340 mm OD, 75 mm-wide assembled set. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30332UUTG resolves to 160 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The 90.0 mm radial section carries the roller complement across the 160–340 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The 7.3 kN-per-mm-bore capacity figure for 30332UUTG summarises the 1170 kN rating over 160 mm bore; use it to sanity-check an interchange candidate before swapping brands. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 160 mm pair is misadjusted and the 75 mm T set will edge-load in service.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 160 mm bore the 30332UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1170 kN C level.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 160 mm bore; do not swap to the lighter family without re-checking the 1,100 r/min grease limit and the thrust load split.", "Do not confuse T (75 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Grease packs must leave free volume in the 75 mm-wide set; over-greasing a paired bearing churning at the 1,600 r/min oil-band speed raises temperature and destroys the preload setting.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30332UUTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 1170/1200 kN ratings and 110 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30332UUTG (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30332UUTG?", "a": "30332UUTG is a metric 4T tapered roller bearing to ISO 355: 160 mm bore, 340 mm outside diameter and 75 mm assembled width T (6.299 × 13.386 × 2.953 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1170 kN, C0 1200 kN, Pu 110 kN, grease limiting speed 1,100 r/min, oil speed 1,600 r/min, mass about 29800 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30332UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30332UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30332UUTG designation encode the 160 mm bore and what is 2GB?", "a": "last two digits 32 are the ISO bore code, ×5 = 160 mm (codes 00–03 use the 10/12/15/17 exception table). The 340 mm OD and 75 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30332UUTG list two speeds, 1,100 and 1,600 r/min?", "a": "The lower figure, 1,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30332UUTG at 1,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30332UUTG mean?", "a": "Suffix reading on 30332UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30332UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30332uutg", "＊30332uutg", "30332UUTG" ], "locale_variants": {} }, { "sku": "32332UTG", "brand": "NTN", "manufacturer_designation": "NTN 32332UTG", "series": "32300-series", "type": "tapered_roller", "d_mm": 160, "D_mm": 340, "B_mm": 121, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1580, "static_load_kN": 1840, "fatigue_load_limit_kN": 170, "limiting_speed_rpm": 1100, "max_rpm": 1100, "speed_oil_rpm": 1600, "weight_g": 48900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32332UTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 160×340 mm ISO 355 envelope, with 121 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 160×340 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32332UTG, not only the raceway. The 90.0 mm section height over the 160 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Fillet radii must clear the ring chamfers of the 340 mm cup and 160 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 160 mm bore the 32332UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1580 kN C level.", "The extra-heavy 32300 family at 160 mm bore (340×121 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,600 r/min oil ceiling.", "The 90.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32332UTG or the ring will bottom out on the radius instead of the shoulder face.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 160 mm shoulder geometry, because retrofitting flips the cups.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 160 mm shoulder geometry, because retrofitting flips the cups.", "The 1580/1840 kN ratings and 170 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32332UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32332UTG?", "a": "32332UTG is a metric 4T tapered roller bearing to ISO 355: 160 mm bore, 340 mm outside diameter and 121 mm assembled width T (6.299 × 13.386 × 4.764 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1580 kN, C0 1840 kN, Pu 170 kN, grease limiting speed 1,100 r/min, oil speed 1,600 r/min, mass about 48900 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32332UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32332UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32332UTG designation encode the 160 mm bore?", "a": "last two digits 32 are the ISO bore code, ×5 = 160 mm (codes 00–03 use the 10/12/15/17 exception table). The 340 mm OD and 121 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32332UTG list two speeds, 1,100 and 1,600 r/min?", "a": "The lower figure, 1,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32332UTG at 1,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32332UTG mean?", "a": "Suffix reading on 32332UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32332UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32332utg", "＊32332utg", "32332UTG" ], "locale_variants": {} }, { "sku": "32934XU", "brand": "NTN", "manufacturer_designation": "NTN 32934XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 170, "D_mm": 230, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 315, "static_load_kN": 560, "fatigue_load_limit_kN": 55, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1800, "weight_g": 4400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 170 mm shaft with a thrust component, NTN lists 32934XU, a metric 4T tapered roller bearing of 315 kN C and 560 kN C0 inside the 230 mm OD, 38 mm-wide assembled set. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 170 mm; 230 mm OD and 38 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32934XU, not only the raceway. Catalogue mass of the 32934XU set is 4400 g (0.173 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 170 mm pair is misadjusted and the 38 mm T set will edge-load in service.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 170 mm bore the 32934XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 315 kN C level.", "The thin 38 mm section of 32934XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 170 mm bore smears the roller ends against the rib.", "Do not confuse T (38 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Grease packs must leave free volume in the 38 mm-wide set; over-greasing a paired bearing churning at the 1,800 r/min oil-band speed raises temperature and destroys the preload setting.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 170 mm shoulder geometry, because retrofitting flips the cups.", "The 315/560 kN ratings and 55 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32934XU (ISO 355 3DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32934XU?", "a": "32934XU is a metric 4T tapered roller bearing to ISO 355: 170 mm bore, 230 mm outside diameter and 38 mm assembled width T (6.693 × 9.055 × 1.496 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 315 kN, C0 560 kN, Pu 55 kN, grease limiting speed 1,400 r/min, oil speed 1,800 r/min, mass about 4400 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32934XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32934XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32934XU designation encode the 170 mm bore and what is 3DC?", "a": "last two digits 34 are the ISO bore code, ×5 = 170 mm (codes 00–03 use the 10/12/15/17 exception table). The 230 mm OD and 38 mm assembled T follow the ISO 355 dimension-series plan. 3DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32934XU list two speeds, 1,400 and 1,800 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32934XU at 1,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32934XU mean?", "a": "Suffix reading on 32934XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32934XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32934xu", "3dc", "32934XU" ], "locale_variants": {} }, { "sku": "32034XU", "brand": "NTN", "manufacturer_designation": "NTN 32034XU", "series": "32000-series", "type": "tapered_roller", "d_mm": 170, "D_mm": 260, "B_mm": 57, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 555, "static_load_kN": 895, "fatigue_load_limit_kN": 86.5, "limiting_speed_rpm": 1300, "max_rpm": 1300, "speed_oil_rpm": 1700, "weight_g": 10600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32034XU in the low-section 32000 family tuned for low friction: 170 mm bore, 260 mm cup OD, 57 mm T, with a grease limiting speed of 1,300 r/min and an oil-lubricated ceiling of 1,700 r/min. Digit by digit, the bare number identifies the low-section 32000 family tuned for low friction and a bore code resolving to 170 mm; 260 mm OD and 57 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The printed contact-angle geometry gives the low-section 32000 family tuned for low friction its characteristic load split — at 555/895 kN (C/C0) the static rating is about 1.61× C, typical of tapered bearings proportioned for heavy combined duty. The fatigue load limit Pu printed for 32034XU is 86.5 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32034XU arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 170 mm bore the 32034XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 555 kN C level.", "The thin 57 mm section of 32034XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 170 mm bore smears the roller ends against the rib.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32034XU by size alone can deliver the wrong contact-angle execution for a pinion position.", "Replacing one half of an adjusted pair without resetting end play negates the 57 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Minimum load matters at high speed: an unloaded 32034XU at a large fraction of 1,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 555/895 kN ratings and 86.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32034XU (ISO 355 4EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32034XU?", "a": "32034XU is a metric 4T tapered roller bearing to ISO 355: 170 mm bore, 260 mm outside diameter and 57 mm assembled width T (6.693 × 10.236 × 2.244 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 555 kN, C0 895 kN, Pu 86.5 kN, grease limiting speed 1,300 r/min, oil speed 1,700 r/min, mass about 10600 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32034XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32034XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32034XU designation encode the 170 mm bore and what is 4EC?", "a": "last two digits 34 are the ISO bore code, ×5 = 170 mm (codes 00–03 use the 10/12/15/17 exception table). The 260 mm OD and 57 mm assembled T follow the ISO 355 dimension-series plan. 4EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32034XU list two speeds, 1,300 and 1,700 r/min?", "a": "The lower figure, 1,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32034XU at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32034XU mean?", "a": "Suffix reading on 32034XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32034XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32034xu", "4ec", "32034XU" ], "locale_variants": {} }, { "sku": "30234UUTG", "brand": "NTN", "manufacturer_designation": "NTN 30234UUTG", "series": "30200-series", "type": "tapered_roller", "d_mm": 170, "D_mm": 310, "B_mm": 57, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 780, "static_load_kN": 845, "fatigue_load_limit_kN": 79.5, "limiting_speed_rpm": 1100, "max_rpm": 1100, "speed_oil_rpm": 1600, "weight_g": 16900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30234UUTG belongs to the NTN metric 4T tapered roller range (standard-section 30200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30234UUTG resolves to 170 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 30234UUTG cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The fatigue load limit Pu printed for 30234UUTG is 79.5 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 170 mm pair is misadjusted and the 57 mm T set will edge-load in service.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 170 mm bore the 30234UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 780 kN C level.", "The standard-section 30200 family at 170 mm bore (310×57 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,600 r/min oil ceiling.", "Grease packs must leave free volume in the 57 mm-wide set; over-greasing a paired bearing churning at the 1,600 r/min oil-band speed raises temperature and destroys the preload setting.", "Replacing one half of an adjusted pair without resetting end play negates the 57 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (57 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 780/845 kN ratings and 79.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30234UUTG (ISO 355 4GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30234UUTG?", "a": "30234UUTG is a metric 4T tapered roller bearing to ISO 355: 170 mm bore, 310 mm outside diameter and 57 mm assembled width T (6.693 × 12.205 × 2.244 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 780 kN, C0 845 kN, Pu 79.5 kN, grease limiting speed 1,100 r/min, oil speed 1,600 r/min, mass about 16900 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30234UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30234UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30234UUTG designation encode the 170 mm bore and what is 4GB?", "a": "last two digits 34 are the ISO bore code, ×5 = 170 mm (codes 00–03 use the 10/12/15/17 exception table). The 310 mm OD and 57 mm assembled T follow the ISO 355 dimension-series plan. 4GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30234UUTG list two speeds, 1,100 and 1,600 r/min?", "a": "The lower figure, 1,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30234UUTG at 1,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30234UUTG mean?", "a": "Suffix reading on 30234UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30234UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30234uutg", "4gb", "＊30234uutg", "30234UUTG" ], "locale_variants": {} }, { "sku": "32234UUTG", "brand": "NTN", "manufacturer_designation": "NTN 32234UUTG", "series": "32200-series", "type": "tapered_roller", "d_mm": 170, "D_mm": 310, "B_mm": 91, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1280, "static_load_kN": 1600, "fatigue_load_limit_kN": 150, "limiting_speed_rpm": 1100, "max_rpm": 1100, "speed_oil_rpm": 1600, "weight_g": 29200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32234UUTG is the NTN 4T catalogue entry for a 170×310×91 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4GD, which is the maker-neutral cross-reference for the 170×310 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Speed planning uses both catalogue columns: grease 1,100 r/min is the cage/rib mechanical ceiling for 32234UUTG, oil 1,600 r/min is available with circulating oil — a 500 r/min margin at this size. Open 4T bearings need application seals; without them the grease at the cone rib of 32234UUTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 170 mm bore the 32234UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1280 kN C level.", "The heavy-section 32200 family at 170 mm bore (310×91 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,600 r/min oil ceiling.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32234UUTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "Never fit the 170 mm cone by hammering the 310 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Replacing one half of an adjusted pair without resetting end play negates the 91 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 1280/1600 kN ratings and 150 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32234UUTG (ISO 355 4GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32234UUTG?", "a": "32234UUTG is a metric 4T tapered roller bearing to ISO 355: 170 mm bore, 310 mm outside diameter and 91 mm assembled width T (6.693 × 12.205 × 3.583 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1280 kN, C0 1600 kN, Pu 150 kN, grease limiting speed 1,100 r/min, oil speed 1,600 r/min, mass about 29200 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32234UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32234UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32234UUTG designation encode the 170 mm bore and what is 4GD?", "a": "last two digits 34 are the ISO bore code, ×5 = 170 mm (codes 00–03 use the 10/12/15/17 exception table). The 310 mm OD and 91 mm assembled T follow the ISO 355 dimension-series plan. 4GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32234UUTG list two speeds, 1,100 and 1,600 r/min?", "a": "The lower figure, 1,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32234UUTG at 1,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32234UUTG mean?", "a": "Suffix reading on 32234UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32234UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32234uutg", "4gd", "＊32234uutg", "32234UUTG" ], "locale_variants": {} }, { "sku": "30334UUTG", "brand": "NTN", "manufacturer_designation": "NTN 30334UUTG", "series": "30300-series", "type": "tapered_roller", "d_mm": 170, "D_mm": 360, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1290, "static_load_kN": 1320, "fatigue_load_limit_kN": 120, "limiting_speed_rpm": 1000, "max_rpm": 1000, "speed_oil_rpm": 1500, "weight_g": 35200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30334UUTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 170×360 mm ISO 355 envelope, with 80 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30334UUTG by the metric ISO 355 number (ISO series abbreviation 2GB): 170 mm bore, 360 mm OD. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. The 7.6 kN-per-mm-bore capacity figure for 30334UUTG summarises the 1290 kN rating over 170 mm bore; use it to sanity-check an interchange candidate before swapping brands. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 170 mm pair is misadjusted and the 80 mm T set will edge-load in service.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 170 mm bore the 30334UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1290 kN C level.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 170 mm bore; do not swap to the lighter family without re-checking the 1,000 r/min grease limit and the thrust load split.", "Grease packs must leave free volume in the 80 mm-wide set; over-greasing a paired bearing churning at the 1,500 r/min oil-band speed raises temperature and destroys the preload setting.", "Open 30334UUTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,000 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 80 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 1290/1320 kN ratings and 120 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30334UUTG (ISO 355 2GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30334UUTG?", "a": "30334UUTG is a metric 4T tapered roller bearing to ISO 355: 170 mm bore, 360 mm outside diameter and 80 mm assembled width T (6.693 × 14.173 × 3.15 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1290 kN, C0 1320 kN, Pu 120 kN, grease limiting speed 1,000 r/min, oil speed 1,500 r/min, mass about 35200 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30334UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30334UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30334UUTG designation encode the 170 mm bore and what is 2GB?", "a": "last two digits 34 are the ISO bore code, ×5 = 170 mm (codes 00–03 use the 10/12/15/17 exception table). The 360 mm OD and 80 mm assembled T follow the ISO 355 dimension-series plan. 2GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30334UUTG list two speeds, 1,000 and 1,500 r/min?", "a": "The lower figure, 1,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30334UUTG at 1,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30334UUTG mean?", "a": "Suffix reading on 30334UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30334UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2gb", "30334uutg", "＊30334uutg", "30334UUTG" ], "locale_variants": {} }, { "sku": "32334UTG", "brand": "NTN", "manufacturer_designation": "NTN 32334UTG", "series": "32300-series", "type": "tapered_roller", "d_mm": 170, "D_mm": 360, "B_mm": 127, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1680, "static_load_kN": 1940, "fatigue_load_limit_kN": 177, "limiting_speed_rpm": 1000, "max_rpm": 1000, "speed_oil_rpm": 1500, "weight_g": 56500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32334UTG is the NTN 4T catalogue entry for a 170×360×127 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Digit by digit, the bare number identifies the extra-heavy 32300 family and a bore code resolving to 170 mm; 360 mm OD and 127 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32334UTG, not only the raceway. Selection: C 1680 kN against C0 1940 kN gives a C0/C ratio of 1.15 for the 170 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 170 mm pair is misadjusted and the 127 mm T set will edge-load in service.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 170 mm bore the 32334UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1680 kN C level.", "The extra-heavy 32300 family at 170 mm bore (360×127 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,500 r/min oil ceiling.", "Grease packs must leave free volume in the 127 mm-wide set; over-greasing a paired bearing churning at the 1,500 r/min oil-band speed raises temperature and destroys the preload setting.", "Never fit the 170 mm cone by hammering the 360 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 170 mm shoulder geometry, because retrofitting flips the cups.", "The 1680/1940 kN ratings and 177 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32334UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32334UTG?", "a": "32334UTG is a metric 4T tapered roller bearing to ISO 355: 170 mm bore, 360 mm outside diameter and 127 mm assembled width T (6.693 × 14.173 × 5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1680 kN, C0 1940 kN, Pu 177 kN, grease limiting speed 1,000 r/min, oil speed 1,500 r/min, mass about 56500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32334UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32334UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32334UTG designation encode the 170 mm bore?", "a": "last two digits 34 are the ISO bore code, ×5 = 170 mm (codes 00–03 use the 10/12/15/17 exception table). The 360 mm OD and 127 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32334UTG list two speeds, 1,000 and 1,500 r/min?", "a": "The lower figure, 1,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32334UTG at 1,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32334UTG mean?", "a": "Suffix reading on 32334UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32334UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32334utg", "＊32334utg", "32334UTG" ], "locale_variants": {} }, { "sku": "32936XU", "brand": "NTN", "manufacturer_designation": "NTN 32936XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 180, "D_mm": 250, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 390, "static_load_kN": 700, "fatigue_load_limit_kN": 68, "limiting_speed_rpm": 1300, "max_rpm": 1300, "speed_oil_rpm": 1700, "weight_g": 6550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32936XU in the extra-light thin-section 32900 family: 180 mm bore, 250 mm cup OD, 45 mm T, with a grease limiting speed of 1,300 r/min and an oil-lubricated ceiling of 1,700 r/min. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32936XU resolves to 180 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. At 390 kN C the bearing offers about 2.2 kN of dynamic capacity per millimetre of the 180 mm bore — compare any substitution on this ratio and the 45 mm assembled T, not on bore alone. The two speed columns differ by a factor of .76 (grease/limiting 1,300 vs oil 1,700 r/min); heat generation at the cone rib decides which lubrication a real 32936XU arrangement can sustain. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32936XU arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 180 mm bore the 32936XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 390 kN C level.", "The thin 45 mm section of 32936XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 180 mm bore smears the roller ends against the rib.", "Grease packs must leave free volume in the 45 mm-wide set; over-greasing a paired bearing churning at the 1,700 r/min oil-band speed raises temperature and destroys the preload setting.", "Never fit the 180 mm cone by hammering the 250 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 32936XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,300 r/min grease figure is meaningless once water reaches the cone rib.", "The 390/700 kN ratings and 68 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32936XU (ISO 355 4DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32936XU?", "a": "32936XU is a metric 4T tapered roller bearing to ISO 355: 180 mm bore, 250 mm outside diameter and 45 mm assembled width T (7.087 × 9.843 × 1.772 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 390 kN, C0 700 kN, Pu 68 kN, grease limiting speed 1,300 r/min, oil speed 1,700 r/min, mass about 6550 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32936XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32936XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32936XU designation encode the 180 mm bore and what is 4DC?", "a": "last two digits 36 are the ISO bore code, ×5 = 180 mm (codes 00–03 use the 10/12/15/17 exception table). The 250 mm OD and 45 mm assembled T follow the ISO 355 dimension-series plan. 4DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32936XU list two speeds, 1,300 and 1,700 r/min?", "a": "The lower figure, 1,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32936XU at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32936XU mean?", "a": "Suffix reading on 32936XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32936XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32936xu", "4dc", "32936XU" ], "locale_variants": {} }, { "sku": "32036XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32036XUUTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 180, "D_mm": 280, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 825, "static_load_kN": 1170, "fatigue_load_limit_kN": 111, "limiting_speed_rpm": 1200, "max_rpm": 1200, "speed_oil_rpm": 1700, "weight_g": 14500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32036XUUTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 180×280 mm ISO 355 envelope, with 64 mm overall assembled width T. Digit by digit, the bare number identifies the low-section 32000 family tuned for low friction and a bore code resolving to 180 mm; 280 mm OD and 64 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. Individually mounted, 32036XUUTG takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Catalogue mass of the 32036XUUTG set is 14500 g (0.571 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Mount the 180 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32036XUUTG.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 180 mm bore the 32036XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 825 kN C level.", "The thin 64 mm section of 32036XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 180 mm bore smears the roller ends against the rib.", "Do not confuse T (64 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Do not confuse T (64 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Never fit the 180 mm cone by hammering the 280 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 825/1170 kN ratings and 111 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32036XUUTG (ISO 355 3FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32036XUUTG?", "a": "32036XUUTG is a metric 4T tapered roller bearing to ISO 355: 180 mm bore, 280 mm outside diameter and 64 mm assembled width T (7.087 × 11.024 × 2.52 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 825 kN, C0 1170 kN, Pu 111 kN, grease limiting speed 1,200 r/min, oil speed 1,700 r/min, mass about 14500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32036XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32036XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32036XUUTG designation encode the 180 mm bore and what is 3FD?", "a": "last two digits 36 are the ISO bore code, ×5 = 180 mm (codes 00–03 use the 10/12/15/17 exception table). The 280 mm OD and 64 mm assembled T follow the ISO 355 dimension-series plan. 3FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32036XUUTG list two speeds, 1,200 and 1,700 r/min?", "a": "The lower figure, 1,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32036XUUTG at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32036XUUTG mean?", "a": "Suffix reading on 32036XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32036XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32036xuutg", "3fd", "＊32036xuutg", "32036XUUTG" ], "locale_variants": {} }, { "sku": "30236UUTG", "brand": "NTN", "manufacturer_designation": "NTN 30236UUTG", "series": "30200-series", "type": "tapered_roller", "d_mm": 180, "D_mm": 320, "B_mm": 57, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 805, "static_load_kN": 890, "fatigue_load_limit_kN": 82.5, "limiting_speed_rpm": 1100, "max_rpm": 1100, "speed_oil_rpm": 1500, "weight_g": 17800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30236UUTG belongs to the NTN metric 4T tapered roller range (standard-section 30200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30236UUTG by the metric ISO 355 number (ISO series abbreviation 4GB): 180 mm bore, 320 mm OD. Suffix reading on 30236UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles. The fatigue load limit Pu printed for 30236UUTG is 82.5 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 30236UUTG arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 180 mm bore the 30236UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 805 kN C level.", "The standard-section 30200 family at 180 mm bore (320×57 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,500 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 57 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 70.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30236UUTG or the ring will bottom out on the radius instead of the shoulder face.", "ISO 355 makes the 180×320 mm envelope interchangeable but not the ratings: NTN prints 805/890 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 805/890 kN ratings and 82.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30236UUTG (ISO 355 4GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30236UUTG?", "a": "30236UUTG is a metric 4T tapered roller bearing to ISO 355: 180 mm bore, 320 mm outside diameter and 57 mm assembled width T (7.087 × 12.598 × 2.244 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 805 kN, C0 890 kN, Pu 82.5 kN, grease limiting speed 1,100 r/min, oil speed 1,500 r/min, mass about 17800 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30236UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30236UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30236UUTG designation encode the 180 mm bore and what is 4GB?", "a": "last two digits 36 are the ISO bore code, ×5 = 180 mm (codes 00–03 use the 10/12/15/17 exception table). The 320 mm OD and 57 mm assembled T follow the ISO 355 dimension-series plan. 4GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30236UUTG list two speeds, 1,100 and 1,500 r/min?", "a": "The lower figure, 1,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30236UUTG at 1,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30236UUTG mean?", "a": "Suffix reading on 30236UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30236UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30236uutg", "4gb", "＊30236uutg", "30236UUTG" ], "locale_variants": {} }, { "sku": "32236UUTG", "brand": "NTN", "manufacturer_designation": "NTN 32236UUTG", "series": "32200-series", "type": "tapered_roller", "d_mm": 180, "D_mm": 320, "B_mm": 91, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1320, "static_load_kN": 1690, "fatigue_load_limit_kN": 157, "limiting_speed_rpm": 1100, "max_rpm": 1100, "speed_oil_rpm": 1500, "weight_g": 30400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32236UUTG is the NTN 4T catalogue entry for a 180×320×91 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. The last two digits 36 are the ISO bore code, ×5 = 180 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 91 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Individually mounted, 32236UUTG takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The two speed columns differ by a factor of .73 (grease/limiting 1,100 vs oil 1,500 r/min); heat generation at the cone rib decides which lubrication a real 32236UUTG arrangement can sustain. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 32236UUTG; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 180 mm bore the 32236UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1320 kN C level.", "The heavy-section 32200 family at 180 mm bore (320×91 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,500 r/min oil ceiling.", "Grease packs must leave free volume in the 91 mm-wide set; over-greasing a paired bearing churning at the 1,500 r/min oil-band speed raises temperature and destroys the preload setting.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 180 mm shoulder geometry, because retrofitting flips the cups.", "Never fit the 180 mm cone by hammering the 320 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 1320/1690 kN ratings and 157 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32236UUTG (ISO 355 4GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32236UUTG?", "a": "32236UUTG is a metric 4T tapered roller bearing to ISO 355: 180 mm bore, 320 mm outside diameter and 91 mm assembled width T (7.087 × 12.598 × 3.583 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1320 kN, C0 1690 kN, Pu 157 kN, grease limiting speed 1,100 r/min, oil speed 1,500 r/min, mass about 30400 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32236UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32236UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32236UUTG designation encode the 180 mm bore and what is 4GD?", "a": "last two digits 36 are the ISO bore code, ×5 = 180 mm (codes 00–03 use the 10/12/15/17 exception table). The 320 mm OD and 91 mm assembled T follow the ISO 355 dimension-series plan. 4GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32236UUTG list two speeds, 1,100 and 1,500 r/min?", "a": "The lower figure, 1,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32236UUTG at 1,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32236UUTG mean?", "a": "Suffix reading on 32236UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32236UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32236uutg", "4gd", "＊32236uutg", "32236UUTG" ], "locale_variants": {} }, { "sku": "30336UTG", "brand": "NTN", "manufacturer_designation": "NTN 30336UTG", "series": "30300-series", "type": "tapered_roller", "d_mm": 180, "D_mm": 380, "B_mm": 83, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1170, "static_load_kN": 1190, "fatigue_load_limit_kN": 107, "limiting_speed_rpm": 960, "max_rpm": 960, "speed_oil_rpm": 1400, "weight_g": 38900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30336UTG belongs to the NTN metric 4T tapered roller range (large-OD 30300 family with the steeper contact angle); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. The last two digits 36 are the ISO bore code, ×5 = 180 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 83 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 30336UTG cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Speed planning uses both catalogue columns: grease 960 r/min is the cage/rib mechanical ceiling for 30336UTG, oil 1,400 r/min is available with circulating oil — a 440 r/min margin at this size. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 30336UTG arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 180 mm bore the 30336UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1170 kN C level.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 180 mm bore; do not swap to the lighter family without re-checking the 960 r/min grease limit and the thrust load split.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30336UTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "Do not confuse T (83 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Do not confuse T (83 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 1170/1190 kN ratings and 107 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30336UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30336UTG?", "a": "30336UTG is a metric 4T tapered roller bearing to ISO 355: 180 mm bore, 380 mm outside diameter and 83 mm assembled width T (7.087 × 14.961 × 3.268 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1170 kN, C0 1190 kN, Pu 107 kN, grease limiting speed 960 r/min, oil speed 1,400 r/min, mass about 38900 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30336UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30336UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30336UTG designation encode the 180 mm bore?", "a": "last two digits 36 are the ISO bore code, ×5 = 180 mm (codes 00–03 use the 10/12/15/17 exception table). The 380 mm OD and 83 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30336UTG list two speeds, 960 and 1,400 r/min?", "a": "The lower figure, 960 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30336UTG at 1,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30336UTG mean?", "a": "Suffix reading on 30336UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30336UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30336utg", "＊30336utg", "30336UTG" ], "locale_variants": {} }, { "sku": "32336UTG", "brand": "NTN", "manufacturer_designation": "NTN 32336UTG", "series": "32300-series", "type": "tapered_roller", "d_mm": 180, "D_mm": 380, "B_mm": 134, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1850, "static_load_kN": 2150, "fatigue_load_limit_kN": 192, "limiting_speed_rpm": 960, "max_rpm": 960, "speed_oil_rpm": 1400, "weight_g": 67700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32336UTG belongs to the NTN metric 4T tapered roller range (extra-heavy 32300 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32336UTG resolves to 180 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32336UTG, not only the raceway. Grease relubrication at 960 r/min limiting speed targets the rib contact; if the drive needs 1,400 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. When pairing 32336UTG with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 180 mm bore the 32336UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1850 kN C level.", "The extra-heavy 32300 family at 180 mm bore (380×134 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,400 r/min oil ceiling.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 180 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 100.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32336UTG or the ring will bottom out on the radius instead of the shoulder face.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 180 mm shoulder geometry, because retrofitting flips the cups.", "The 1850/2150 kN ratings and 192 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32336UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32336UTG?", "a": "32336UTG is a metric 4T tapered roller bearing to ISO 355: 180 mm bore, 380 mm outside diameter and 134 mm assembled width T (7.087 × 14.961 × 5.276 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1850 kN, C0 2150 kN, Pu 192 kN, grease limiting speed 960 r/min, oil speed 1,400 r/min, mass about 67700 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32336UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32336UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32336UTG designation encode the 180 mm bore?", "a": "last two digits 36 are the ISO bore code, ×5 = 180 mm (codes 00–03 use the 10/12/15/17 exception table). The 380 mm OD and 134 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32336UTG list two speeds, 960 and 1,400 r/min?", "a": "The lower figure, 960 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32336UTG at 1,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32336UTG mean?", "a": "Suffix reading on 32336UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32336UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32336utg", "＊32336utg", "32336UTG" ], "locale_variants": {} }, { "sku": "32938-NTN", "brand": "NTN", "manufacturer_designation": "NTN 32938", "series": "32900-series", "type": "tapered_roller", "d_mm": 190, "D_mm": 260, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 310, "static_load_kN": 525, "fatigue_load_limit_kN": 50.5, "limiting_speed_rpm": 1200, "max_rpm": 1200, "speed_oil_rpm": 1600, "weight_g": 6270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 190 mm bore tapered roller position as 32938: one cone assembly, one cup, line-contact rollers and a steel cage, rated 310 kN basic dynamic and 525 kN static on the extra-light thin-section 32900 family. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 190×260 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. The fatigue load limit Pu printed for 32938 is 50.5 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 32938; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 190 mm bore the 32938 set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 310 kN C level.", "The thin 45 mm section of 32938 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 190 mm bore smears the roller ends against the rib.", "Never fit the 190 mm cone by hammering the 260 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Replacing one half of an adjusted pair without resetting end play negates the 45 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 45 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 310/525 kN ratings and 50.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32938; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32938?", "a": "32938 is a metric 4T tapered roller bearing to ISO 355: 190 mm bore, 260 mm outside diameter and 45 mm assembled width T (7.48 × 10.236 × 1.772 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 310 kN, C0 525 kN, Pu 50.5 kN, grease limiting speed 1,200 r/min, oil speed 1,600 r/min, mass about 6270 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32938?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32938); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32938 designation encode the 190 mm bore?", "a": "last two digits 38 are the ISO bore code, ×5 = 190 mm (codes 00–03 use the 10/12/15/17 exception table). The 260 mm OD and 45 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32938 list two speeds, 1,200 and 1,600 r/min?", "a": "The lower figure, 1,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32938 at 1,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32938 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32938", "equiv_brand": "SKF", "level": "partial", "note": "Same 190×260×45 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "32938-DF", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "○32938", "32938", "32938-NTN" ], "locale_variants": {} }, { "sku": "32938XU", "brand": "NTN", "manufacturer_designation": "NTN 32938XU", "series": "32900-series", "type": "tapered_roller", "d_mm": 190, "D_mm": 260, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 390, "static_load_kN": 710, "fatigue_load_limit_kN": 68, "limiting_speed_rpm": 1200, "max_rpm": 1200, "speed_oil_rpm": 1600, "weight_g": 6820, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32938XU denotes the extra-light thin-section 32900 family of metric tapered roller bearings, 190 mm bore, 260 mm outside diameter and 45 mm assembled width T (7.48 × 10.236 × 1.772 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4DC, which is the maker-neutral cross-reference for the 190×260 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN grades 4T metric bearings as open bearings without integral seals; at 190 mm bore the application supplies the seals and the grease fill or oil supply to the 4DC ISO 355 assembly. The 2.1 kN-per-mm-bore capacity figure for 32938XU summarises the 390 kN rating over 190 mm bore; use it to sanity-check an interchange candidate before swapping brands. Open 4T bearings need application seals; without them the grease at the cone rib of 32938XU washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 190 mm bore the 32938XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 390 kN C level.", "The thin 45 mm section of 32938XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 190 mm bore smears the roller ends against the rib.", "The 35.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32938XU or the ring will bottom out on the radius instead of the shoulder face.", "ISO 355 makes the 190×260 mm envelope interchangeable but not the ratings: NTN prints 390/710 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 35.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32938XU or the ring will bottom out on the radius instead of the shoulder face.", "The 390/710 kN ratings and 68 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32938XU (ISO 355 4DC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32938XU?", "a": "32938XU is a metric 4T tapered roller bearing to ISO 355: 190 mm bore, 260 mm outside diameter and 45 mm assembled width T (7.48 × 10.236 × 1.772 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 390 kN, C0 710 kN, Pu 68 kN, grease limiting speed 1,200 r/min, oil speed 1,600 r/min, mass about 6820 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32938XU?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32938XU); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32938XU designation encode the 190 mm bore and what is 4DC?", "a": "last two digits 38 are the ISO bore code, ×5 = 190 mm (codes 00–03 use the 10/12/15/17 exception table). The 260 mm OD and 45 mm assembled T follow the ISO 355 dimension-series plan. 4DC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32938XU list two speeds, 1,200 and 1,600 r/min?", "a": "The lower figure, 1,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32938XU at 1,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32938XU mean?", "a": "Suffix reading on 32938XU: XU combines the X ISO boundary section with the U uprated internal design; U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32938XU", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32938xu", "4dc", "32938XU" ], "locale_variants": {} }, { "sku": "32038XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32038XUUTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 190, "D_mm": 290, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 840, "static_load_kN": 1210, "fatigue_load_limit_kN": 113, "limiting_speed_rpm": 1100, "max_rpm": 1100, "speed_oil_rpm": 1600, "weight_g": 15000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 190 mm shaft with a thrust component, NTN lists 32038XUUTG, a metric 4T tapered roller bearing of 840 kN C and 1210 kN C0 inside the 290 mm OD, 64 mm-wide assembled set. Digit by digit, the bare number identifies the low-section 32000 family tuned for low friction and a bore code resolving to 190 mm; 290 mm OD and 64 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. Suffix reading on 32038XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles. Speed planning uses both catalogue columns: grease 1,100 r/min is the cage/rib mechanical ceiling for 32038XUUTG, oil 1,600 r/min is available with circulating oil — a 500 r/min margin at this size. When pairing 32038XUUTG with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 190 mm bore the 32038XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 840 kN C level.", "The thin 64 mm section of 32038XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 190 mm bore smears the roller ends against the rib.", "Never fit the 190 mm cone by hammering the 290 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ISO 355 makes the 190×290 mm envelope interchangeable but not the ratings: NTN prints 840/1210 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "ISO 355 makes the 190×290 mm envelope interchangeable but not the ratings: NTN prints 840/1210 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 840/1210 kN ratings and 113 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32038XUUTG (ISO 355 4FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32038XUUTG?", "a": "32038XUUTG is a metric 4T tapered roller bearing to ISO 355: 190 mm bore, 290 mm outside diameter and 64 mm assembled width T (7.48 × 11.417 × 2.52 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 840 kN, C0 1210 kN, Pu 113 kN, grease limiting speed 1,100 r/min, oil speed 1,600 r/min, mass about 15000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32038XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32038XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32038XUUTG designation encode the 190 mm bore and what is 4FD?", "a": "last two digits 38 are the ISO bore code, ×5 = 190 mm (codes 00–03 use the 10/12/15/17 exception table). The 290 mm OD and 64 mm assembled T follow the ISO 355 dimension-series plan. 4FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32038XUUTG list two speeds, 1,100 and 1,600 r/min?", "a": "The lower figure, 1,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32038XUUTG at 1,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32038XUUTG mean?", "a": "Suffix reading on 32038XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32038XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32038xuutg", "4fd", "＊32038xuutg", "32038XUUTG" ], "locale_variants": {} }, { "sku": "30238UUTG", "brand": "NTN", "manufacturer_designation": "NTN 30238UUTG", "series": "30200-series", "type": "tapered_roller", "d_mm": 190, "D_mm": 340, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 920, "static_load_kN": 1000, "fatigue_load_limit_kN": 91.5, "limiting_speed_rpm": 1000, "max_rpm": 1000, "speed_oil_rpm": 1400, "weight_g": 21500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30238UUTG belongs to the NTN metric 4T tapered roller range (standard-section 30200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30238UUTG resolves to 190 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. At 920 kN C the bearing offers about 4.8 kN of dynamic capacity per millimetre of the 190 mm bore — compare any substitution on this ratio and the 60 mm assembled T, not on bore alone. Selection: C 920 kN against C0 1000 kN gives a C0/C ratio of 1.09 for the 190 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. When pairing 30238UUTG with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 190 mm bore the 30238UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 920 kN C level.", "The standard-section 30200 family at 190 mm bore (340×60 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,400 r/min oil ceiling.", "Never fit the 190 mm cone by hammering the 340 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never fit the 190 mm cone by hammering the 340 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 30238UUTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,000 r/min grease figure is meaningless once water reaches the cone rib.", "The 920/1000 kN ratings and 91.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30238UUTG (ISO 355 4GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30238UUTG?", "a": "30238UUTG is a metric 4T tapered roller bearing to ISO 355: 190 mm bore, 340 mm outside diameter and 60 mm assembled width T (7.48 × 13.386 × 2.362 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 920 kN, C0 1000 kN, Pu 91.5 kN, grease limiting speed 1,000 r/min, oil speed 1,400 r/min, mass about 21500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30238UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30238UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30238UUTG designation encode the 190 mm bore and what is 4GB?", "a": "last two digits 38 are the ISO bore code, ×5 = 190 mm (codes 00–03 use the 10/12/15/17 exception table). The 340 mm OD and 60 mm assembled T follow the ISO 355 dimension-series plan. 4GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30238UUTG list two speeds, 1,000 and 1,400 r/min?", "a": "The lower figure, 1,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30238UUTG at 1,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30238UUTG mean?", "a": "Suffix reading on 30238UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30238UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30238uutg", "4gb", "＊30238uutg", "30238UUTG" ], "locale_variants": {} }, { "sku": "32238UUTG", "brand": "NTN", "manufacturer_designation": "NTN 32238UUTG", "series": "32200-series", "type": "tapered_roller", "d_mm": 190, "D_mm": 340, "B_mm": 97, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1480, "static_load_kN": 1850, "fatigue_load_limit_kN": 169, "limiting_speed_rpm": 1000, "max_rpm": 1000, "speed_oil_rpm": 1400, "weight_g": 36100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32238UUTG is the NTN 4T catalogue entry for a 190×340×97 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32238UUTG by the metric ISO 355 number (ISO series abbreviation 4GD): 190 mm bore, 340 mm OD. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32238UUTG, since running clearance is set during assembly. The 7.8 kN-per-mm-bore capacity figure for 32238UUTG summarises the 1480 kN rating over 190 mm bore; use it to sanity-check an interchange candidate before swapping brands. Fillet radii must clear the ring chamfers of the 340 mm cup and 190 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 190 mm bore the 32238UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1480 kN C level.", "The heavy-section 32200 family at 190 mm bore (340×97 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,400 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 32238UUTG at a large fraction of 1,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 190 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 190 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 1480/1850 kN ratings and 169 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32238UUTG (ISO 355 4GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32238UUTG?", "a": "32238UUTG is a metric 4T tapered roller bearing to ISO 355: 190 mm bore, 340 mm outside diameter and 97 mm assembled width T (7.48 × 13.386 × 3.819 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1480 kN, C0 1850 kN, Pu 169 kN, grease limiting speed 1,000 r/min, oil speed 1,400 r/min, mass about 36100 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32238UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32238UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32238UUTG designation encode the 190 mm bore and what is 4GD?", "a": "last two digits 38 are the ISO bore code, ×5 = 190 mm (codes 00–03 use the 10/12/15/17 exception table). The 340 mm OD and 97 mm assembled T follow the ISO 355 dimension-series plan. 4GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32238UUTG list two speeds, 1,000 and 1,400 r/min?", "a": "The lower figure, 1,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32238UUTG at 1,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32238UUTG mean?", "a": "Suffix reading on 32238UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32238UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32238uutg", "4gd", "＊32238uutg", "32238UUTG" ], "locale_variants": {} }, { "sku": "30338UTG", "brand": "NTN", "manufacturer_designation": "NTN 30338UTG", "series": "30300-series", "type": "tapered_roller", "d_mm": 190, "D_mm": 400, "B_mm": 86, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1200, "static_load_kN": 1200, "fatigue_load_limit_kN": 106, "limiting_speed_rpm": 900, "max_rpm": 900, "speed_oil_rpm": 1300, "weight_g": 43600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 190 mm bore tapered roller position as 30338UTG: one cone assembly, one cup, line-contact rollers and a steel cage, rated 1200 kN basic dynamic and 1200 kN static on the large-OD 30300 family with the steeper contact angle. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 190×400 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 30338UTG cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The 6.3 kN-per-mm-bore capacity figure for 30338UTG summarises the 1200 kN rating over 190 mm bore; use it to sanity-check an interchange candidate before swapping brands. Open 4T bearings need application seals; without them the grease at the cone rib of 30338UTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 190 mm bore the 30338UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1200 kN C level.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 190 mm bore; do not swap to the lighter family without re-checking the 900 r/min grease limit and the thrust load split.", "Never fit the 190 mm cone by hammering the 400 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 190 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Do not confuse T (86 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 1200/1200 kN ratings and 106 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30338UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30338UTG?", "a": "30338UTG is a metric 4T tapered roller bearing to ISO 355: 190 mm bore, 400 mm outside diameter and 86 mm assembled width T (7.48 × 15.748 × 3.386 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1200 kN, C0 1200 kN, Pu 106 kN, grease limiting speed 900 r/min, oil speed 1,300 r/min, mass about 43600 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30338UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30338UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30338UTG designation encode the 190 mm bore?", "a": "last two digits 38 are the ISO bore code, ×5 = 190 mm (codes 00–03 use the 10/12/15/17 exception table). The 400 mm OD and 86 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30338UTG list two speeds, 900 and 1,300 r/min?", "a": "The lower figure, 900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30338UTG at 1,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30338UTG mean?", "a": "Suffix reading on 30338UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30338UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30338utg", "＊30338utg", "30338UTG" ], "locale_variants": {} }, { "sku": "32338UTG", "brand": "NTN", "manufacturer_designation": "NTN 32338UTG", "series": "32300-series", "type": "tapered_roller", "d_mm": 190, "D_mm": 400, "B_mm": 140, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2040, "static_load_kN": 2390, "fatigue_load_limit_kN": 211, "limiting_speed_rpm": 900, "max_rpm": 900, "speed_oil_rpm": 1300, "weight_g": 77000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 190 mm bore tapered roller position as 32338UTG: one cone assembly, one cup, line-contact rollers and a steel cage, rated 2040 kN basic dynamic and 2390 kN static on the extra-heavy 32300 family. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32338UTG by the metric ISO 355 number: 190 mm bore, 400 mm OD. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32338UTG, not only the raceway. Speed planning uses both catalogue columns: grease 900 r/min is the cage/rib mechanical ceiling for 32338UTG, oil 1,300 r/min is available with circulating oil — a 400 r/min margin at this size. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 32338UTG; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 190 mm bore the 32338UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2040 kN C level.", "The extra-heavy 32300 family at 190 mm bore (400×140 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,300 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 140 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 140 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 190 mm shoulder geometry, because retrofitting flips the cups.", "The 2040/2390 kN ratings and 211 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32338UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32338UTG?", "a": "32338UTG is a metric 4T tapered roller bearing to ISO 355: 190 mm bore, 400 mm outside diameter and 140 mm assembled width T (7.48 × 15.748 × 5.512 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2040 kN, C0 2390 kN, Pu 211 kN, grease limiting speed 900 r/min, oil speed 1,300 r/min, mass about 77000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32338UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32338UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32338UTG designation encode the 190 mm bore?", "a": "last two digits 38 are the ISO bore code, ×5 = 190 mm (codes 00–03 use the 10/12/15/17 exception table). The 400 mm OD and 140 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32338UTG list two speeds, 900 and 1,300 r/min?", "a": "The lower figure, 900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32338UTG at 1,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32338UTG mean?", "a": "Suffix reading on 32338UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32338UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32338utg", "＊32338utg", "32338UTG" ], "locale_variants": {} }, { "sku": "32940XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32940XUUTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 200, "D_mm": 280, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 620, "static_load_kN": 895, "fatigue_load_limit_kN": 84, "limiting_speed_rpm": 1100, "max_rpm": 1100, "speed_oil_rpm": 1600, "weight_g": 9280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32940XUUTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 200×280 mm ISO 355 envelope, with 51 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32940XUUTG by the metric ISO 355 number (ISO series abbreviation 3EC): 200 mm bore, 280 mm OD. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32940XUUTG cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The 40.0 mm section height over the 200 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. When pairing 32940XUUTG with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 200 mm bore the 32940XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 620 kN C level.", "The thin 51 mm section of 32940XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 200 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 51 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Minimum load matters at high speed: an unloaded 32940XUUTG at a large fraction of 1,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Do not confuse T (51 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 620/895 kN ratings and 84 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32940XUUTG (ISO 355 3EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32940XUUTG?", "a": "32940XUUTG is a metric 4T tapered roller bearing to ISO 355: 200 mm bore, 280 mm outside diameter and 51 mm assembled width T (7.874 × 11.024 × 2.008 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 620 kN, C0 895 kN, Pu 84 kN, grease limiting speed 1,100 r/min, oil speed 1,600 r/min, mass about 9280 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32940XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32940XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32940XUUTG designation encode the 200 mm bore and what is 3EC?", "a": "last two digits 40 are the ISO bore code, ×5 = 200 mm (codes 00–03 use the 10/12/15/17 exception table). The 280 mm OD and 51 mm assembled T follow the ISO 355 dimension-series plan. 3EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32940XUUTG list two speeds, 1,100 and 1,600 r/min?", "a": "The lower figure, 1,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32940XUUTG at 1,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32940XUUTG mean?", "a": "Suffix reading on 32940XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32940XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32940xuutg", "3ec", "＊32940xuutg", "32940XUUTG" ], "locale_variants": {} }, { "sku": "32040XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32040XUUTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 200, "D_mm": 310, "B_mm": 70, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1030, "static_load_kN": 1470, "fatigue_load_limit_kN": 135, "limiting_speed_rpm": 1100, "max_rpm": 1100, "speed_oil_rpm": 1500, "weight_g": 19200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32040XUUTG is the NTN 4T catalogue entry for a 200×310×70 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4FD, which is the maker-neutral cross-reference for the 200×310 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The 55.0 mm radial section carries the roller complement across the 200–310 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The two speed columns differ by a factor of .73 (grease/limiting 1,100 vs oil 1,500 r/min); heat generation at the cone rib decides which lubrication a real 32040XUUTG arrangement can sustain. Fillet radii must clear the ring chamfers of the 310 mm cup and 200 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 200 mm bore the 32040XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1030 kN C level.", "The thin 70 mm section of 32040XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 200 mm bore smears the roller ends against the rib.", "Never fit the 200 mm cone by hammering the 310 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never fit the 200 mm cone by hammering the 310 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32040XUUTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 1030/1470 kN ratings and 135 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32040XUUTG (ISO 355 4FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32040XUUTG?", "a": "32040XUUTG is a metric 4T tapered roller bearing to ISO 355: 200 mm bore, 310 mm outside diameter and 70 mm assembled width T (7.874 × 12.205 × 2.756 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1030 kN, C0 1470 kN, Pu 135 kN, grease limiting speed 1,100 r/min, oil speed 1,500 r/min, mass about 19200 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32040XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32040XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32040XUUTG designation encode the 200 mm bore and what is 4FD?", "a": "last two digits 40 are the ISO bore code, ×5 = 200 mm (codes 00–03 use the 10/12/15/17 exception table). The 310 mm OD and 70 mm assembled T follow the ISO 355 dimension-series plan. 4FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32040XUUTG list two speeds, 1,100 and 1,500 r/min?", "a": "The lower figure, 1,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32040XUUTG at 1,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32040XUUTG mean?", "a": "Suffix reading on 32040XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32040XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=172", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32040xuutg", "4fd", "＊32040xuutg", "32040XUUTG" ], "locale_variants": {} }, { "sku": "30240UUTG", "brand": "NTN", "manufacturer_designation": "NTN 30240UUTG", "series": "30200-series", "type": "tapered_roller", "d_mm": 200, "D_mm": 360, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1010, "static_load_kN": 1110, "fatigue_load_limit_kN": 99, "limiting_speed_rpm": 950, "max_rpm": 950, "speed_oil_rpm": 1300, "weight_g": 25200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30240UUTG in the standard-section 30200 family: 200 mm bore, 360 mm cup OD, 64 mm T, with a grease limiting speed of 950 r/min and an oil-lubricated ceiling of 1,300 r/min. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30240UUTG by the metric ISO 355 number (ISO series abbreviation 4GB): 200 mm bore, 360 mm OD. Individually mounted, 30240UUTG takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The 80.0 mm section height over the 200 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 200 mm pair is misadjusted and the 64 mm T set will edge-load in service.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 200 mm bore the 30240UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1010 kN C level.", "The standard-section 30200 family at 200 mm bore (360×64 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,300 r/min oil ceiling.", "Never fit the 200 mm cone by hammering the 360 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Minimum load matters at high speed: an unloaded 30240UUTG at a large fraction of 950 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Never fit the 200 mm cone by hammering the 360 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 1010/1110 kN ratings and 99 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30240UUTG (ISO 355 4GB); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30240UUTG?", "a": "30240UUTG is a metric 4T tapered roller bearing to ISO 355: 200 mm bore, 360 mm outside diameter and 64 mm assembled width T (7.874 × 14.173 × 2.52 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1010 kN, C0 1110 kN, Pu 99 kN, grease limiting speed 950 r/min, oil speed 1,300 r/min, mass about 25200 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30240UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30240UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30240UUTG designation encode the 200 mm bore and what is 4GB?", "a": "last two digits 40 are the ISO bore code, ×5 = 200 mm (codes 00–03 use the 10/12/15/17 exception table). The 360 mm OD and 64 mm assembled T follow the ISO 355 dimension-series plan. 4GB is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 30240UUTG list two speeds, 950 and 1,300 r/min?", "a": "The lower figure, 950 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30240UUTG at 1,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30240UUTG mean?", "a": "Suffix reading on 30240UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30240UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30240uutg", "4gb", "＊30240uutg", "30240UUTG" ], "locale_variants": {} }, { "sku": "32240UUTG", "brand": "NTN", "manufacturer_designation": "NTN 32240UUTG", "series": "32200-series", "type": "tapered_roller", "d_mm": 200, "D_mm": 360, "B_mm": 104, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1690, "static_load_kN": 2130, "fatigue_load_limit_kN": 191, "limiting_speed_rpm": 950, "max_rpm": 950, "speed_oil_rpm": 1300, "weight_g": 43800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32240UUTG denotes the heavy-section 32200 family of metric tapered roller bearings, 200 mm bore, 360 mm outside diameter and 104 mm assembled width T (7.874 × 14.173 × 4.094 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the heavy-section 32200 family and a bore code resolving to 200 mm; 360 mm OD and 104 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. 2203E lists two speed ceilings for 32240UUTG: 950 r/min with grease lubrication (the limiting speed) and 1,300 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Catalogue mass of the 32240UUTG set is 43800 g (1.724 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Open 4T bearings need application seals; without them the grease at the cone rib of 32240UUTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 200 mm bore the 32240UUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1690 kN C level.", "The heavy-section 32200 family at 200 mm bore (360×104 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,300 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 104 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 80.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32240UUTG or the ring will bottom out on the radius instead of the shoulder face.", "Grease packs must leave free volume in the 104 mm-wide set; over-greasing a paired bearing churning at the 1,300 r/min oil-band speed raises temperature and destroys the preload setting.", "The 1690/2130 kN ratings and 191 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32240UUTG (ISO 355 3GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32240UUTG?", "a": "32240UUTG is a metric 4T tapered roller bearing to ISO 355: 200 mm bore, 360 mm outside diameter and 104 mm assembled width T (7.874 × 14.173 × 4.094 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1690 kN, C0 2130 kN, Pu 191 kN, grease limiting speed 950 r/min, oil speed 1,300 r/min, mass about 43800 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32240UUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32240UUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32240UUTG designation encode the 200 mm bore and what is 3GD?", "a": "last two digits 40 are the ISO bore code, ×5 = 200 mm (codes 00–03 use the 10/12/15/17 exception table). The 360 mm OD and 104 mm assembled T follow the ISO 355 dimension-series plan. 3GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32240UUTG list two speeds, 950 and 1,300 r/min?", "a": "The lower figure, 950 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32240UUTG at 1,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32240UUTG mean?", "a": "Suffix reading on 32240UUTG: the UUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32240UUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32240uutg", "3gd", "＊32240uutg", "32240UUTG" ], "locale_variants": {} }, { "sku": "30340UTG", "brand": "NTN", "manufacturer_designation": "NTN 30340UTG", "series": "30300-series", "type": "tapered_roller", "d_mm": 200, "D_mm": 420, "B_mm": 89, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1340, "static_load_kN": 1370, "fatigue_load_limit_kN": 119, "limiting_speed_rpm": 850, "max_rpm": 850, "speed_oil_rpm": 1200, "weight_g": 51500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 200 mm shaft with a thrust component, NTN lists 30340UTG, a metric 4T tapered roller bearing of 1340 kN C and 1370 kN C0 inside the 420 mm OD, 89 mm-wide assembled set. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 200×420 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 30340UTG, not only the raceway. The 6.7 kN-per-mm-bore capacity figure for 30340UTG summarises the 1340 kN rating over 200 mm bore; use it to sanity-check an interchange candidate before swapping brands. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 200 mm pair is misadjusted and the 89 mm T set will edge-load in service.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 200 mm bore the 30340UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1340 kN C level.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 200 mm bore; do not swap to the lighter family without re-checking the 850 r/min grease limit and the thrust load split.", "Open 30340UTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 850 r/min grease figure is meaningless once water reaches the cone rib.", "Do not confuse T (89 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 200 mm shoulder geometry, because retrofitting flips the cups.", "The 1340/1370 kN ratings and 119 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30340UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30340UTG?", "a": "30340UTG is a metric 4T tapered roller bearing to ISO 355: 200 mm bore, 420 mm outside diameter and 89 mm assembled width T (7.874 × 16.535 × 3.504 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1340 kN, C0 1370 kN, Pu 119 kN, grease limiting speed 850 r/min, oil speed 1,200 r/min, mass about 51500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30340UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30340UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30340UTG designation encode the 200 mm bore?", "a": "last two digits 40 are the ISO bore code, ×5 = 200 mm (codes 00–03 use the 10/12/15/17 exception table). The 420 mm OD and 89 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30340UTG list two speeds, 850 and 1,200 r/min?", "a": "The lower figure, 850 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30340UTG at 1,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30340UTG mean?", "a": "Suffix reading on 30340UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30340UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30340utg", "＊30340utg", "30340UTG" ], "locale_variants": {} }, { "sku": "32340UTG", "brand": "NTN", "manufacturer_designation": "NTN 32340UTG", "series": "32300-series", "type": "tapered_roller", "d_mm": 200, "D_mm": 420, "B_mm": 146, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2240, "static_load_kN": 2650, "fatigue_load_limit_kN": 230, "limiting_speed_rpm": 850, "max_rpm": 850, "speed_oil_rpm": 1200, "weight_g": 89600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 200 mm shaft with a thrust component, NTN lists 32340UTG, a metric 4T tapered roller bearing of 2240 kN C and 2650 kN C0 inside the 420 mm OD, 146 mm-wide assembled set. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32340UTG by the metric ISO 355 number: 200 mm bore, 420 mm OD. NTN grades 4T metric bearings as open bearings without integral seals; at 200 mm bore the application supplies the seals and the grease fill or oil supply to the ISO 355 assembly. Speed planning uses both catalogue columns: grease 850 r/min is the cage/rib mechanical ceiling for 32340UTG, oil 1,200 r/min is available with circulating oil — a 350 r/min margin at this size. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32340UTG arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 200 mm bore the 32340UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2240 kN C level.", "The extra-heavy 32300 family at 200 mm bore (420×146 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,200 r/min oil ceiling.", "ISO 355 makes the 200×420 mm envelope interchangeable but not the ratings: NTN prints 2240/2650 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 110.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32340UTG or the ring will bottom out on the radius instead of the shoulder face.", "The 110.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32340UTG or the ring will bottom out on the radius instead of the shoulder face.", "The 2240/2650 kN ratings and 230 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32340UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32340UTG?", "a": "32340UTG is a metric 4T tapered roller bearing to ISO 355: 200 mm bore, 420 mm outside diameter and 146 mm assembled width T (7.874 × 16.535 × 5.748 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2240 kN, C0 2650 kN, Pu 230 kN, grease limiting speed 850 r/min, oil speed 1,200 r/min, mass about 89600 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32340UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32340UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32340UTG designation encode the 200 mm bore?", "a": "last two digits 40 are the ISO bore code, ×5 = 200 mm (codes 00–03 use the 10/12/15/17 exception table). The 420 mm OD and 146 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32340UTG list two speeds, 850 and 1,200 r/min?", "a": "The lower figure, 850 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32340UTG at 1,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32340UTG mean?", "a": "Suffix reading on 32340UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32340UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32340utg", "＊32340utg", "32340UTG" ], "locale_variants": {} }, { "sku": "32944E1", "brand": "NTN", "manufacturer_designation": "NTN 32944E1", "series": "32900-series", "type": "tapered_roller", "d_mm": 220, "D_mm": 300, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 385, "static_load_kN": 670, "fatigue_load_limit_kN": 61, "limiting_speed_rpm": 1000, "max_rpm": 1000, "speed_oil_rpm": 1400, "weight_g": 9470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32944E1 denotes the extra-light thin-section 32900 family of metric tapered roller bearings, 220 mm bore, 300 mm outside diameter and 51 mm assembled width T (8.661 × 11.811 × 2.008 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 220×300 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Grease relubrication at 1,000 r/min limiting speed targets the rib contact; if the drive needs 1,400 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. When pairing 32944E1 with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 220 mm bore the 32944E1 set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 385 kN C level.", "The thin 51 mm section of 32944E1 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 220 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 51 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 220 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "Replacing one half of an adjusted pair without resetting end play negates the 51 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 385/670 kN ratings and 61 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32944E1; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32944E1?", "a": "32944E1 is a metric 4T tapered roller bearing to ISO 355: 220 mm bore, 300 mm outside diameter and 51 mm assembled width T (8.661 × 11.811 × 2.008 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 385 kN, C0 670 kN, Pu 61 kN, grease limiting speed 1,000 r/min, oil speed 1,400 r/min, mass about 9470 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32944E1?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32944E1); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32944E1 designation encode the 220 mm bore?", "a": "last two digits E1 are the ISO bore code, ×5 = 220 mm (codes 00–03 use the 10/12/15/17 exception table). The 300 mm OD and 51 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32944E1 list two speeds, 1,000 and 1,400 r/min?", "a": "The lower figure, 1,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32944E1 at 1,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32944E1 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32944E1", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32944e1", "○32944e1", "32944E1" ], "locale_variants": {} }, { "sku": "32944XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32944XUUTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 220, "D_mm": 300, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 615, "static_load_kN": 950, "fatigue_load_limit_kN": 87, "limiting_speed_rpm": 1000, "max_rpm": 1000, "speed_oil_rpm": 1500, "weight_g": 9980, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32944XUUTG is the NTN 4T catalogue entry for a 220×300×51 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32944XUUTG by the metric ISO 355 number (ISO series abbreviation 3EC): 220 mm bore, 300 mm OD. The 40.0 mm radial section carries the roller complement across the 220–300 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The fatigue load limit Pu printed for 32944XUUTG is 87 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 32944XUUTG; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 220 mm bore the 32944XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 615 kN C level.", "The thin 51 mm section of 32944XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 220 mm bore smears the roller ends against the rib.", "Do not confuse T (51 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "ISO 355 makes the 220×300 mm envelope interchangeable but not the ratings: NTN prints 615/950 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32944XUUTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 615/950 kN ratings and 87 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32944XUUTG (ISO 355 3EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32944XUUTG?", "a": "32944XUUTG is a metric 4T tapered roller bearing to ISO 355: 220 mm bore, 300 mm outside diameter and 51 mm assembled width T (8.661 × 11.811 × 2.008 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 615 kN, C0 950 kN, Pu 87 kN, grease limiting speed 1,000 r/min, oil speed 1,500 r/min, mass about 9980 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32944XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32944XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32944XUUTG designation encode the 220 mm bore and what is 3EC?", "a": "last two digits 44 are the ISO bore code, ×5 = 220 mm (codes 00–03 use the 10/12/15/17 exception table). The 300 mm OD and 51 mm assembled T follow the ISO 355 dimension-series plan. 3EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32944XUUTG list two speeds, 1,000 and 1,500 r/min?", "a": "The lower figure, 1,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32944XUUTG at 1,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32944XUUTG mean?", "a": "Suffix reading on 32944XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32944XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32944xuutg", "3ec", "＊32944xuutg", "32944XUUTG" ], "locale_variants": {} }, { "sku": "32044XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32044XUUTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 220, "D_mm": 340, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1180, "static_load_kN": 1690, "fatigue_load_limit_kN": 152, "limiting_speed_rpm": 960, "max_rpm": 960, "speed_oil_rpm": 1400, "weight_g": 24900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32044XUUTG denotes the low-section 32000 family tuned for low friction of metric tapered roller bearings, 220 mm bore, 340 mm outside diameter and 76 mm assembled width T (8.661 × 13.386 × 2.992 in) to the ISO 355 boundary plan. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4FD, which is the maker-neutral cross-reference for the 220×340 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The printed contact-angle geometry gives the low-section 32000 family tuned for low friction its characteristic load split — at 1180/1690 kN (C/C0) the static rating is about 1.43× C, typical of tapered bearings proportioned for heavy combined duty. The 5.4 kN-per-mm-bore capacity figure for 32044XUUTG summarises the 1180 kN rating over 220 mm bore; use it to sanity-check an interchange candidate before swapping brands. Mount the 220 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32044XUUTG.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 220 mm bore the 32044XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1180 kN C level.", "The thin 76 mm section of 32044XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 220 mm bore smears the roller ends against the rib.", "ISO 355 makes the 220×340 mm envelope interchangeable but not the ratings: NTN prints 1180/1690 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Minimum load matters at high speed: an unloaded 32044XUUTG at a large fraction of 960 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Minimum load matters at high speed: an unloaded 32044XUUTG at a large fraction of 960 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 1180/1690 kN ratings and 152 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32044XUUTG (ISO 355 4FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32044XUUTG?", "a": "32044XUUTG is a metric 4T tapered roller bearing to ISO 355: 220 mm bore, 340 mm outside diameter and 76 mm assembled width T (8.661 × 13.386 × 2.992 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1180 kN, C0 1690 kN, Pu 152 kN, grease limiting speed 960 r/min, oil speed 1,400 r/min, mass about 24900 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32044XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32044XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32044XUUTG designation encode the 220 mm bore and what is 4FD?", "a": "last two digits 44 are the ISO bore code, ×5 = 220 mm (codes 00–03 use the 10/12/15/17 exception table). The 340 mm OD and 76 mm assembled T follow the ISO 355 dimension-series plan. 4FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32044XUUTG list two speeds, 960 and 1,400 r/min?", "a": "The lower figure, 960 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32044XUUTG at 1,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32044XUUTG mean?", "a": "Suffix reading on 32044XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32044XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32044xuutg", "4fd", "＊32044xuutg", "32044XUUTG" ], "locale_variants": {} }, { "sku": "30244UTG", "brand": "NTN", "manufacturer_designation": "NTN 30244UTG", "series": "30200-series", "type": "tapered_roller", "d_mm": 220, "D_mm": 400, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1050, "static_load_kN": 1220, "fatigue_load_limit_kN": 106, "limiting_speed_rpm": 840, "max_rpm": 840, "speed_oil_rpm": 1200, "weight_g": 34800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30244UTG in the standard-section 30200 family: 220 mm bore, 400 mm cup OD, 72 mm T, with a grease limiting speed of 840 r/min and an oil-lubricated ceiling of 1,200 r/min. Digit by digit, the bare number identifies the standard-section 30200 family and a bore code resolving to 220 mm; 400 mm OD and 72 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. At 1050 kN C the bearing offers about 4.8 kN of dynamic capacity per millimetre of the 220 mm bore — compare any substitution on this ratio and the 72 mm assembled T, not on bore alone. The 4.8 kN-per-mm-bore capacity figure for 30244UTG summarises the 1050 kN rating over 220 mm bore; use it to sanity-check an interchange candidate before swapping brands. Fillet radii must clear the ring chamfers of the 400 mm cup and 220 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 220 mm bore the 30244UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1050 kN C level.", "The standard-section 30200 family at 220 mm bore (400×72 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,200 r/min oil ceiling.", "Never fit the 220 mm cone by hammering the 400 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Replacing one half of an adjusted pair without resetting end play negates the 72 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 30244UTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 840 r/min grease figure is meaningless once water reaches the cone rib.", "The 1050/1220 kN ratings and 106 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30244UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30244UTG?", "a": "30244UTG is a metric 4T tapered roller bearing to ISO 355: 220 mm bore, 400 mm outside diameter and 72 mm assembled width T (8.661 × 15.748 × 2.835 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1050 kN, C0 1220 kN, Pu 106 kN, grease limiting speed 840 r/min, oil speed 1,200 r/min, mass about 34800 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30244UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30244UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30244UTG designation encode the 220 mm bore?", "a": "last two digits 44 are the ISO bore code, ×5 = 220 mm (codes 00–03 use the 10/12/15/17 exception table). The 400 mm OD and 72 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30244UTG list two speeds, 840 and 1,200 r/min?", "a": "The lower figure, 840 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30244UTG at 1,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30244UTG mean?", "a": "Suffix reading on 30244UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30244UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30244utg", "＊30244utg", "30244UTG" ], "locale_variants": {} }, { "sku": "32244UTG", "brand": "NTN", "manufacturer_designation": "NTN 32244UTG", "series": "32200-series", "type": "tapered_roller", "d_mm": 220, "D_mm": 400, "B_mm": 114, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1780, "static_load_kN": 2410, "fatigue_load_limit_kN": 209, "limiting_speed_rpm": 840, "max_rpm": 840, "speed_oil_rpm": 1200, "weight_g": 59800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32244UTG in the heavy-section 32200 family: 220 mm bore, 400 mm cup OD, 114 mm T, with a grease limiting speed of 840 r/min and an oil-lubricated ceiling of 1,200 r/min. The last two digits 44 are the ISO bore code, ×5 = 220 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 114 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Suffix reading on 32244UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles. Speed planning uses both catalogue columns: grease 840 r/min is the cage/rib mechanical ceiling for 32244UTG, oil 1,200 r/min is available with circulating oil — a 360 r/min margin at this size. Mount the 220 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32244UTG.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 220 mm bore the 32244UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1780 kN C level.", "The heavy-section 32200 family at 220 mm bore (400×114 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,200 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 114 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ISO 355 makes the 220×400 mm envelope interchangeable but not the ratings: NTN prints 1780/2410 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "ISO 355 makes the 220×400 mm envelope interchangeable but not the ratings: NTN prints 1780/2410 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 1780/2410 kN ratings and 209 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32244UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32244UTG?", "a": "32244UTG is a metric 4T tapered roller bearing to ISO 355: 220 mm bore, 400 mm outside diameter and 114 mm assembled width T (8.661 × 15.748 × 4.488 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1780 kN, C0 2410 kN, Pu 209 kN, grease limiting speed 840 r/min, oil speed 1,200 r/min, mass about 59800 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32244UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32244UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32244UTG designation encode the 220 mm bore?", "a": "last two digits 44 are the ISO bore code, ×5 = 220 mm (codes 00–03 use the 10/12/15/17 exception table). The 400 mm OD and 114 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32244UTG list two speeds, 840 and 1,200 r/min?", "a": "The lower figure, 840 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32244UTG at 1,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32244UTG mean?", "a": "Suffix reading on 32244UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32244UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32244utg", "＊32244utg", "32244UTG" ], "locale_variants": {} }, { "sku": "30344UTG", "brand": "NTN", "manufacturer_designation": "NTN 30344UTG", "series": "30300-series", "type": "tapered_roller", "d_mm": 220, "D_mm": 460, "B_mm": 97, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1620, "static_load_kN": 1690, "fatigue_load_limit_kN": 142, "limiting_speed_rpm": 770, "max_rpm": 770, "speed_oil_rpm": 1100, "weight_g": 66600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30344UTG in the large-OD 30300 family with the steeper contact angle: 220 mm bore, 460 mm cup OD, 97 mm T, with a grease limiting speed of 770 r/min and an oil-lubricated ceiling of 1,100 r/min. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 220×460 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 30344UTG, not only the raceway. Grease relubrication at 770 r/min limiting speed targets the rib contact; if the drive needs 1,100 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 30344UTG; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 220 mm bore the 30344UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1620 kN C level.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 220 mm bore; do not swap to the lighter family without re-checking the 770 r/min grease limit and the thrust load split.", "Replacing one half of an adjusted pair without resetting end play negates the 97 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 220 mm shoulder geometry, because retrofitting flips the cups.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 220 mm shoulder geometry, because retrofitting flips the cups.", "The 1620/1690 kN ratings and 142 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30344UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30344UTG?", "a": "30344UTG is a metric 4T tapered roller bearing to ISO 355: 220 mm bore, 460 mm outside diameter and 97 mm assembled width T (8.661 × 18.11 × 3.819 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1620 kN, C0 1690 kN, Pu 142 kN, grease limiting speed 770 r/min, oil speed 1,100 r/min, mass about 66600 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30344UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30344UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30344UTG designation encode the 220 mm bore?", "a": "last two digits 44 are the ISO bore code, ×5 = 220 mm (codes 00–03 use the 10/12/15/17 exception table). The 460 mm OD and 97 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30344UTG list two speeds, 770 and 1,100 r/min?", "a": "The lower figure, 770 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30344UTG at 1,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30344UTG mean?", "a": "Suffix reading on 30344UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30344UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30344utg", "＊30344utg", "30344UTG" ], "locale_variants": {} }, { "sku": "32344UTG", "brand": "NTN", "manufacturer_designation": "NTN 32344UTG", "series": "32300-series", "type": "tapered_roller", "d_mm": 220, "D_mm": 460, "B_mm": 154, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2590, "static_load_kN": 3050, "fatigue_load_limit_kN": 259, "limiting_speed_rpm": 770, "max_rpm": 770, "speed_oil_rpm": 1100, "weight_g": 110000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32344UTG in the extra-heavy 32300 family: 220 mm bore, 460 mm cup OD, 154 mm T, with a grease limiting speed of 770 r/min and an oil-lubricated ceiling of 1,100 r/min. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 220×460 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Speed planning uses both catalogue columns: grease 770 r/min is the cage/rib mechanical ceiling for 32344UTG, oil 1,100 r/min is available with circulating oil — a 330 r/min margin at this size. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 220 mm pair is misadjusted and the 154 mm T set will edge-load in service.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 220 mm bore the 32344UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2590 kN C level.", "The extra-heavy 32300 family at 220 mm bore (460×154 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,100 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 32344UTG at a large fraction of 770 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Grease packs must leave free volume in the 154 mm-wide set; over-greasing a paired bearing churning at the 1,100 r/min oil-band speed raises temperature and destroys the preload setting.", "Replacing one half of an adjusted pair without resetting end play negates the 154 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 2590/3050 kN ratings and 259 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32344UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32344UTG?", "a": "32344UTG is a metric 4T tapered roller bearing to ISO 355: 220 mm bore, 460 mm outside diameter and 154 mm assembled width T (8.661 × 18.11 × 6.063 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2590 kN, C0 3050 kN, Pu 259 kN, grease limiting speed 770 r/min, oil speed 1,100 r/min, mass about 110000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32344UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32344UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32344UTG designation encode the 220 mm bore?", "a": "last two digits 44 are the ISO bore code, ×5 = 220 mm (codes 00–03 use the 10/12/15/17 exception table). The 460 mm OD and 154 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32344UTG list two speeds, 770 and 1,100 r/min?", "a": "The lower figure, 770 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32344UTG at 1,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32344UTG mean?", "a": "Suffix reading on 32344UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32344UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32344utg", "＊32344utg", "32344UTG" ], "locale_variants": {} }, { "sku": "32948XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32948XUUTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 240, "D_mm": 320, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 625, "static_load_kN": 1000, "fatigue_load_limit_kN": 90, "limiting_speed_rpm": 940, "max_rpm": 940, "speed_oil_rpm": 1300, "weight_g": 10900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32948XUUTG denotes the extra-light thin-section 32900 family of metric tapered roller bearings, 240 mm bore, 320 mm outside diameter and 51 mm assembled width T (9.449 × 12.598 × 2.008 in) to the ISO 355 boundary plan. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32948XUUTG by the metric ISO 355 number (ISO series abbreviation 4EC): 240 mm bore, 320 mm OD. At 625 kN C the bearing offers about 2.6 kN of dynamic capacity per millimetre of the 240 mm bore — compare any substitution on this ratio and the 51 mm assembled T, not on bore alone. The two speed columns differ by a factor of .72 (grease/limiting 940 vs oil 1,300 r/min); heat generation at the cone rib decides which lubrication a real 32948XUUTG arrangement can sustain. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 240 mm pair is misadjusted and the 51 mm T set will edge-load in service.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 240 mm bore the 32948XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 625 kN C level.", "The thin 51 mm section of 32948XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 240 mm bore smears the roller ends against the rib.", "Minimum load matters at high speed: an unloaded 32948XUUTG at a large fraction of 940 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Never fit the 240 mm cone by hammering the 320 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 32948XUUTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 940 r/min grease figure is meaningless once water reaches the cone rib.", "The 625/1000 kN ratings and 90 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32948XUUTG (ISO 355 4EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32948XUUTG?", "a": "32948XUUTG is a metric 4T tapered roller bearing to ISO 355: 240 mm bore, 320 mm outside diameter and 51 mm assembled width T (9.449 × 12.598 × 2.008 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 625 kN, C0 1000 kN, Pu 90 kN, grease limiting speed 940 r/min, oil speed 1,300 r/min, mass about 10900 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32948XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32948XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32948XUUTG designation encode the 240 mm bore and what is 4EC?", "a": "last two digits 48 are the ISO bore code, ×5 = 240 mm (codes 00–03 use the 10/12/15/17 exception table). The 320 mm OD and 51 mm assembled T follow the ISO 355 dimension-series plan. 4EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32948XUUTG list two speeds, 940 and 1,300 r/min?", "a": "The lower figure, 940 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32948XUUTG at 1,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32948XUUTG mean?", "a": "Suffix reading on 32948XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32948XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32948xuutg", "4ec", "＊32948xuutg", "32948XUUTG" ], "locale_variants": {} }, { "sku": "32048XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32048XUUTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 240, "D_mm": 360, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1190, "static_load_kN": 1760, "fatigue_load_limit_kN": 154, "limiting_speed_rpm": 870, "max_rpm": 870, "speed_oil_rpm": 1200, "weight_g": 26500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32048XUUTG belongs to the NTN metric 4T tapered roller range (low-section 32000 family tuned for low friction); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4FD, which is the maker-neutral cross-reference for the 240×360 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. Individually mounted, 32048XUUTG takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Catalogue mass of the 32048XUUTG set is 26500 g (1.043 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. When pairing 32048XUUTG with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 240 mm bore the 32048XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1190 kN C level.", "The thin 76 mm section of 32048XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 240 mm bore smears the roller ends against the rib.", "The 60.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32048XUUTG or the ring will bottom out on the radius instead of the shoulder face.", "Do not confuse T (76 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Never fit the 240 mm cone by hammering the 360 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 1190/1760 kN ratings and 154 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32048XUUTG (ISO 355 4FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32048XUUTG?", "a": "32048XUUTG is a metric 4T tapered roller bearing to ISO 355: 240 mm bore, 360 mm outside diameter and 76 mm assembled width T (9.449 × 14.173 × 2.992 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1190 kN, C0 1760 kN, Pu 154 kN, grease limiting speed 870 r/min, oil speed 1,200 r/min, mass about 26500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32048XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32048XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32048XUUTG designation encode the 240 mm bore and what is 4FD?", "a": "last two digits 48 are the ISO bore code, ×5 = 240 mm (codes 00–03 use the 10/12/15/17 exception table). The 360 mm OD and 76 mm assembled T follow the ISO 355 dimension-series plan. 4FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32048XUUTG list two speeds, 870 and 1,200 r/min?", "a": "The lower figure, 870 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32048XUUTG at 1,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32048XUUTG mean?", "a": "Suffix reading on 32048XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32048XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32048xuutg", "4fd", "＊32048xuutg", "32048XUUTG" ], "locale_variants": {} }, { "sku": "30248UTG", "brand": "NTN", "manufacturer_designation": "NTN 30248UTG", "series": "30200-series", "type": "tapered_roller", "d_mm": 240, "D_mm": 440, "B_mm": 79, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1250, "static_load_kN": 1480, "fatigue_load_limit_kN": 125, "limiting_speed_rpm": 760, "max_rpm": 760, "speed_oil_rpm": 1100, "weight_g": 47700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30248UTG is the NTN 4T catalogue entry for a 240×440×79 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30248UTG by the metric ISO 355 number: 240 mm bore, 440 mm OD. At 1250 kN C the bearing offers about 5.2 kN of dynamic capacity per millimetre of the 240 mm bore — compare any substitution on this ratio and the 79 mm assembled T, not on bore alone. Imperial cross-check for the drawing: 240×440×79 mm is 9.449 × 17.323 × 3.11 in; ISO 355 makes the envelope interchangeable but C/C0, 1250/1480 kN, is NTN-specific. When pairing 30248UTG with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 240 mm bore the 30248UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1250 kN C level.", "The standard-section 30200 family at 240 mm bore (440×79 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,100 r/min oil ceiling.", "Do not confuse T (79 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Open 30248UTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 760 r/min grease figure is meaningless once water reaches the cone rib.", "Open 30248UTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 760 r/min grease figure is meaningless once water reaches the cone rib.", "The 1250/1480 kN ratings and 125 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30248UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30248UTG?", "a": "30248UTG is a metric 4T tapered roller bearing to ISO 355: 240 mm bore, 440 mm outside diameter and 79 mm assembled width T (9.449 × 17.323 × 3.11 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1250 kN, C0 1480 kN, Pu 125 kN, grease limiting speed 760 r/min, oil speed 1,100 r/min, mass about 47700 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30248UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30248UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30248UTG designation encode the 240 mm bore?", "a": "last two digits 48 are the ISO bore code, ×5 = 240 mm (codes 00–03 use the 10/12/15/17 exception table). The 440 mm OD and 79 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30248UTG list two speeds, 760 and 1,100 r/min?", "a": "The lower figure, 760 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30248UTG at 1,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30248UTG mean?", "a": "Suffix reading on 30248UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30248UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30248utg", "＊30248utg", "30248UTG" ], "locale_variants": {} }, { "sku": "32248UTG", "brand": "NTN", "manufacturer_designation": "NTN 32248UTG", "series": "32200-series", "type": "tapered_roller", "d_mm": 240, "D_mm": 440, "B_mm": 127, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2180, "static_load_kN": 2750, "fatigue_load_limit_kN": 232, "limiting_speed_rpm": 760, "max_rpm": 760, "speed_oil_rpm": 1100, "weight_g": 78900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32248UTG is the NTN 4T catalogue entry for a 240×440×127 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Digit by digit, the bare number identifies the heavy-section 32200 family and a bore code resolving to 240 mm; 440 mm OD and 127 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The 100.0 mm radial section carries the roller complement across the 240–440 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Speed planning uses both catalogue columns: grease 760 r/min is the cage/rib mechanical ceiling for 32248UTG, oil 1,100 r/min is available with circulating oil — a 340 r/min margin at this size. Fillet radii must clear the ring chamfers of the 440 mm cup and 240 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 240 mm bore the 32248UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2180 kN C level.", "The heavy-section 32200 family at 240 mm bore (440×127 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 1,100 r/min oil ceiling.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 240 mm shoulder geometry, because retrofitting flips the cups.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 240 mm shoulder geometry, because retrofitting flips the cups.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32248UTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 2180/2750 kN ratings and 232 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32248UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32248UTG?", "a": "32248UTG is a metric 4T tapered roller bearing to ISO 355: 240 mm bore, 440 mm outside diameter and 127 mm assembled width T (9.449 × 17.323 × 5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2180 kN, C0 2750 kN, Pu 232 kN, grease limiting speed 760 r/min, oil speed 1,100 r/min, mass about 78900 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32248UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32248UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32248UTG designation encode the 240 mm bore?", "a": "last two digits 48 are the ISO bore code, ×5 = 240 mm (codes 00–03 use the 10/12/15/17 exception table). The 440 mm OD and 127 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32248UTG list two speeds, 760 and 1,100 r/min?", "a": "The lower figure, 760 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32248UTG at 1,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32248UTG mean?", "a": "Suffix reading on 32248UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32248UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32248utg", "＊32248utg", "32248UTG" ], "locale_variants": {} }, { "sku": "30348UTG", "brand": "NTN", "manufacturer_designation": "NTN 30348UTG", "series": "30300-series", "type": "tapered_roller", "d_mm": 240, "D_mm": 500, "B_mm": 105, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1900, "static_load_kN": 2000, "fatigue_load_limit_kN": 165, "limiting_speed_rpm": 690, "max_rpm": 690, "speed_oil_rpm": 990, "weight_g": 88300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "30348UTG is the NTN 4T catalogue entry for a 240×500×105 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30348UTG resolves to 240 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Individually mounted, 30348UTG takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Grease relubrication at 690 r/min limiting speed targets the rib contact; if the drive needs 990 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Open 4T bearings need application seals; without them the grease at the cone rib of 30348UTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 240 mm bore the 30348UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1900 kN C level.", "The steeper contact angle of the large-OD 30300 family with the steeper contact angle raises axial capacity but lowers the speed ceiling against a 302/322 bearing at 240 mm bore; do not swap to the lighter family without re-checking the 690 r/min grease limit and the thrust load split.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 240 mm shoulder geometry, because retrofitting flips the cups.", "Minimum load matters at high speed: an unloaded 30348UTG at a large fraction of 690 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Never fit the 240 mm cone by hammering the 500 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 1900/2000 kN ratings and 165 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30348UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30348UTG?", "a": "30348UTG is a metric 4T tapered roller bearing to ISO 355: 240 mm bore, 500 mm outside diameter and 105 mm assembled width T (9.449 × 19.685 × 4.134 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1900 kN, C0 2000 kN, Pu 165 kN, grease limiting speed 690 r/min, oil speed 990 r/min, mass about 88300 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30348UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30348UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30348UTG designation encode the 240 mm bore?", "a": "last two digits 48 are the ISO bore code, ×5 = 240 mm (codes 00–03 use the 10/12/15/17 exception table). The 500 mm OD and 105 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30348UTG list two speeds, 690 and 990 r/min?", "a": "The lower figure, 690 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30348UTG at 990 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30348UTG mean?", "a": "Suffix reading on 30348UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30348UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30348utg", "＊30348utg", "30348UTG" ], "locale_variants": {} }, { "sku": "32952XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32952XUUTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 260, "D_mm": 360, "B_mm": 63.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 905, "static_load_kN": 1430, "fatigue_load_limit_kN": 124, "limiting_speed_rpm": 860, "max_rpm": 860, "speed_oil_rpm": 1200, "weight_g": 18700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32952XUUTG belongs to the NTN metric 4T tapered roller range (extra-light thin-section 32900 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32952XUUTG resolves to 260 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The 50.0 mm radial section carries the roller complement across the 260–360 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Grease relubrication at 860 r/min limiting speed targets the rib contact; if the drive needs 1,200 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Open 4T bearings need application seals; without them the grease at the cone rib of 32952XUUTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 260 mm bore the 32952XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 905 kN C level.", "The thin 63.5 mm section of 32952XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 260 mm bore smears the roller ends against the rib.", "ISO 355 makes the 260×360 mm envelope interchangeable but not the ratings: NTN prints 905/1430 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 50.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32952XUUTG or the ring will bottom out on the radius instead of the shoulder face.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32952XUUTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 905/1430 kN ratings and 124 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32952XUUTG (ISO 355 3EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32952XUUTG?", "a": "32952XUUTG is a metric 4T tapered roller bearing to ISO 355: 260 mm bore, 360 mm outside diameter and 63.5 mm assembled width T (10.236 × 14.173 × 2.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 905 kN, C0 1430 kN, Pu 124 kN, grease limiting speed 860 r/min, oil speed 1,200 r/min, mass about 18700 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32952XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32952XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32952XUUTG designation encode the 260 mm bore and what is 3EC?", "a": "last two digits 52 are the ISO bore code, ×5 = 260 mm (codes 00–03 use the 10/12/15/17 exception table). The 360 mm OD and 63.5 mm assembled T follow the ISO 355 dimension-series plan. 3EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32952XUUTG list two speeds, 860 and 1,200 r/min?", "a": "The lower figure, 860 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32952XUUTG at 1,200 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32952XUUTG mean?", "a": "Suffix reading on 32952XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32952XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32952xuutg", "3ec", "＊32952xuutg", "32952XUUTG" ], "locale_variants": {} }, { "sku": "32052XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32052XUUTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 260, "D_mm": 400, "B_mm": 87, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1540, "static_load_kN": 2270, "fatigue_load_limit_kN": 193, "limiting_speed_rpm": 800, "max_rpm": 800, "speed_oil_rpm": 1100, "weight_g": 39000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 260 mm bore tapered roller position as 32052XUUTG: one cone assembly, one cup, line-contact rollers and a steel cage, rated 1540 kN basic dynamic and 2270 kN static on the low-section 32000 family tuned for low friction. The last two digits 52 are the ISO bore code, ×5 = 260 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 87 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. Suffix reading on 32052XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles. Selection: C 1540 kN against C0 2270 kN gives a C0/C ratio of 1.47 for the 260 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Mount the 260 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32052XUUTG.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 260 mm bore the 32052XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1540 kN C level.", "The thin 87 mm section of 32052XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 260 mm bore smears the roller ends against the rib.", "Open 32052XUUTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 800 r/min grease figure is meaningless once water reaches the cone rib.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 260 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "ISO 355 makes the 260×400 mm envelope interchangeable but not the ratings: NTN prints 1540/2270 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 1540/2270 kN ratings and 193 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32052XUUTG (ISO 355 4FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32052XUUTG?", "a": "32052XUUTG is a metric 4T tapered roller bearing to ISO 355: 260 mm bore, 400 mm outside diameter and 87 mm assembled width T (10.236 × 15.748 × 3.425 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1540 kN, C0 2270 kN, Pu 193 kN, grease limiting speed 800 r/min, oil speed 1,100 r/min, mass about 39000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32052XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32052XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32052XUUTG designation encode the 260 mm bore and what is 4FC?", "a": "last two digits 52 are the ISO bore code, ×5 = 260 mm (codes 00–03 use the 10/12/15/17 exception table). The 400 mm OD and 87 mm assembled T follow the ISO 355 dimension-series plan. 4FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32052XUUTG list two speeds, 800 and 1,100 r/min?", "a": "The lower figure, 800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32052XUUTG at 1,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32052XUUTG mean?", "a": "Suffix reading on 32052XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32052XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32052xuutg", "4fc", "＊32052xuutg", "32052XUUTG" ], "locale_variants": {} }, { "sku": "30252UTG", "brand": "NTN", "manufacturer_designation": "NTN 30252UTG", "series": "30200-series", "type": "tapered_roller", "d_mm": 260, "D_mm": 480, "B_mm": 89, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1500, "static_load_kN": 1810, "fatigue_load_limit_kN": 149, "limiting_speed_rpm": 690, "max_rpm": 690, "speed_oil_rpm": 990, "weight_g": 63400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 260 mm bore tapered roller position as 30252UTG: one cone assembly, one cup, line-contact rollers and a steel cage, rated 1500 kN basic dynamic and 1810 kN static on the standard-section 30200 family. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30252UTG resolves to 260 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The 110.0 mm radial section carries the roller complement across the 260–480 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Selection: C 1500 kN against C0 1810 kN gives a C0/C ratio of 1.21 for the 260 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 30252UTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 260 mm bore the 30252UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1500 kN C level.", "The standard-section 30200 family at 260 mm bore (480×89 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 990 r/min oil ceiling.", "ISO 355 makes the 260×480 mm envelope interchangeable but not the ratings: NTN prints 1500/1810 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "ISO 355 makes the 260×480 mm envelope interchangeable but not the ratings: NTN prints 1500/1810 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30252UTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 1500/1810 kN ratings and 149 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30252UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30252UTG?", "a": "30252UTG is a metric 4T tapered roller bearing to ISO 355: 260 mm bore, 480 mm outside diameter and 89 mm assembled width T (10.236 × 18.898 × 3.504 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1500 kN, C0 1810 kN, Pu 149 kN, grease limiting speed 690 r/min, oil speed 990 r/min, mass about 63400 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30252UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30252UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30252UTG designation encode the 260 mm bore?", "a": "last two digits 52 are the ISO bore code, ×5 = 260 mm (codes 00–03 use the 10/12/15/17 exception table). The 480 mm OD and 89 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30252UTG list two speeds, 690 and 990 r/min?", "a": "The lower figure, 690 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30252UTG at 990 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30252UTG mean?", "a": "Suffix reading on 30252UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30252UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30252utg", "＊30252utg", "30252UTG" ], "locale_variants": {} }, { "sku": "32252UTG", "brand": "NTN", "manufacturer_designation": "NTN 32252UTG", "series": "32200-series", "type": "tapered_roller", "d_mm": 260, "D_mm": 480, "B_mm": 137, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2410, "static_load_kN": 3350, "fatigue_load_limit_kN": 275, "limiting_speed_rpm": 690, "max_rpm": 690, "speed_oil_rpm": 990, "weight_g": 100000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 260 mm bore tapered roller position as 32252UTG: one cone assembly, one cup, line-contact rollers and a steel cage, rated 2410 kN basic dynamic and 3350 kN static on the heavy-section 32200 family. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 260×480 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32252UTG, since running clearance is set during assembly. The 110.0 mm section height over the 260 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 32252UTG; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 260 mm bore the 32252UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2410 kN C level.", "The heavy-section 32200 family at 260 mm bore (480×137 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 990 r/min oil ceiling.", "Do not confuse T (137 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 260 mm shoulder geometry, because retrofitting flips the cups.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 260 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 2410/3350 kN ratings and 275 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32252UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32252UTG?", "a": "32252UTG is a metric 4T tapered roller bearing to ISO 355: 260 mm bore, 480 mm outside diameter and 137 mm assembled width T (10.236 × 18.898 × 5.394 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2410 kN, C0 3350 kN, Pu 275 kN, grease limiting speed 690 r/min, oil speed 990 r/min, mass about 100000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32252UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32252UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32252UTG designation encode the 260 mm bore?", "a": "last two digits 52 are the ISO bore code, ×5 = 260 mm (codes 00–03 use the 10/12/15/17 exception table). The 480 mm OD and 137 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32252UTG list two speeds, 690 and 990 r/min?", "a": "The lower figure, 690 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32252UTG at 990 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32252UTG mean?", "a": "Suffix reading on 32252UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32252UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32252utg", "＊32252utg", "32252UTG" ], "locale_variants": {} }, { "sku": "32956XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32956XUUTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 280, "D_mm": 380, "B_mm": 63.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 930, "static_load_kN": 1520, "fatigue_load_limit_kN": 129, "limiting_speed_rpm": 790, "max_rpm": 790, "speed_oil_rpm": 1100, "weight_g": 19900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "NTN supplies this 280 mm bore tapered roller position as 32956XUUTG: one cone assembly, one cup, line-contact rollers and a steel cage, rated 930 kN basic dynamic and 1520 kN static on the extra-light thin-section 32900 family. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32956XUUTG resolves to 280 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The 50.0 mm radial section carries the roller complement across the 280–380 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The fatigue load limit Pu printed for 32956XUUTG is 129 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 280 mm pair is misadjusted and the 63.5 mm T set will edge-load in service.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 280 mm bore the 32956XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 930 kN C level.", "The thin 63.5 mm section of 32956XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 280 mm bore smears the roller ends against the rib.", "The 50.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32956XUUTG or the ring will bottom out on the radius instead of the shoulder face.", "ISO 355 makes the 280×380 mm envelope interchangeable but not the ratings: NTN prints 930/1520 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32956XUUTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 930/1520 kN ratings and 129 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32956XUUTG (ISO 355 4EC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32956XUUTG?", "a": "32956XUUTG is a metric 4T tapered roller bearing to ISO 355: 280 mm bore, 380 mm outside diameter and 63.5 mm assembled width T (11.024 × 14.961 × 2.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 930 kN, C0 1520 kN, Pu 129 kN, grease limiting speed 790 r/min, oil speed 1,100 r/min, mass about 19900 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32956XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32956XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32956XUUTG designation encode the 280 mm bore and what is 4EC?", "a": "last two digits 56 are the ISO bore code, ×5 = 280 mm (codes 00–03 use the 10/12/15/17 exception table). The 380 mm OD and 63.5 mm assembled T follow the ISO 355 dimension-series plan. 4EC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32956XUUTG list two speeds, 790 and 1,100 r/min?", "a": "The lower figure, 790 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32956XUUTG at 1,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32956XUUTG mean?", "a": "Suffix reading on 32956XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32956XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32956xuutg", "4ec", "＊32956xuutg", "32956XUUTG" ], "locale_variants": {} }, { "sku": "32056XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32056XUUTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 280, "D_mm": 420, "B_mm": 87, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1570, "static_load_kN": 2350, "fatigue_load_limit_kN": 197, "limiting_speed_rpm": 740, "max_rpm": 740, "speed_oil_rpm": 1000, "weight_g": 40500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32056XUUTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 280×420 mm ISO 355 envelope, with 87 mm overall assembled width T. The last two digits 56 are the ISO bore code, ×5 = 280 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 87 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The printed contact-angle geometry gives the low-section 32000 family tuned for low friction its characteristic load split — at 1570/2350 kN (C/C0) the static rating is about 1.50× C, typical of tapered bearings proportioned for heavy combined duty. The 5.6 kN-per-mm-bore capacity figure for 32056XUUTG summarises the 1570 kN rating over 280 mm bore; use it to sanity-check an interchange candidate before swapping brands. When pairing 32056XUUTG with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 280 mm bore the 32056XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1570 kN C level.", "The thin 87 mm section of 32056XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 280 mm bore smears the roller ends against the rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 280 mm shoulder geometry, because retrofitting flips the cups.", "Minimum load matters at high speed: an unloaded 32056XUUTG at a large fraction of 740 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Minimum load matters at high speed: an unloaded 32056XUUTG at a large fraction of 740 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 1570/2350 kN ratings and 197 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32056XUUTG (ISO 355 4FC); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32056XUUTG?", "a": "32056XUUTG is a metric 4T tapered roller bearing to ISO 355: 280 mm bore, 420 mm outside diameter and 87 mm assembled width T (11.024 × 16.535 × 3.425 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1570 kN, C0 2350 kN, Pu 197 kN, grease limiting speed 740 r/min, oil speed 1,000 r/min, mass about 40500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32056XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32056XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32056XUUTG designation encode the 280 mm bore and what is 4FC?", "a": "last two digits 56 are the ISO bore code, ×5 = 280 mm (codes 00–03 use the 10/12/15/17 exception table). The 420 mm OD and 87 mm assembled T follow the ISO 355 dimension-series plan. 4FC is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32056XUUTG list two speeds, 740 and 1,000 r/min?", "a": "The lower figure, 740 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32056XUUTG at 1,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32056XUUTG mean?", "a": "Suffix reading on 32056XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32056XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32056xuutg", "4fc", "＊32056xuutg", "32056XUUTG" ], "locale_variants": {} }, { "sku": "30256UTG", "brand": "NTN", "manufacturer_designation": "NTN 30256UTG", "series": "30200-series", "type": "tapered_roller", "d_mm": 280, "D_mm": 500, "B_mm": 89, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1590, "static_load_kN": 1910, "fatigue_load_limit_kN": 155, "limiting_speed_rpm": 630, "max_rpm": 630, "speed_oil_rpm": 900, "weight_g": 66500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 30256UTG denotes the standard-section 30200 family of metric tapered roller bearings, 280 mm bore, 500 mm outside diameter and 89 mm assembled width T (11.024 × 19.685 × 3.504 in) to the ISO 355 boundary plan. The last two digits 56 are the ISO bore code, ×5 = 280 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 89 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The 110.0 mm radial section carries the roller complement across the 280–500 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Speed planning uses both catalogue columns: grease 630 r/min is the cage/rib mechanical ceiling for 30256UTG, oil 900 r/min is available with circulating oil — a 270 r/min margin at this size. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 280 mm pair is misadjusted and the 89 mm T set will edge-load in service.", "applications": [ "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 280 mm bore the 30256UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1590 kN C level.", "The standard-section 30200 family at 280 mm bore (500×89 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 900 r/min oil ceiling.", "Minimum load matters at high speed: an unloaded 30256UTG at a large fraction of 630 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Do not confuse T (89 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30256UTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 1590/1910 kN ratings and 155 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30256UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30256UTG?", "a": "30256UTG is a metric 4T tapered roller bearing to ISO 355: 280 mm bore, 500 mm outside diameter and 89 mm assembled width T (11.024 × 19.685 × 3.504 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1590 kN, C0 1910 kN, Pu 155 kN, grease limiting speed 630 r/min, oil speed 900 r/min, mass about 66500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30256UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30256UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30256UTG designation encode the 280 mm bore?", "a": "last two digits 56 are the ISO bore code, ×5 = 280 mm (codes 00–03 use the 10/12/15/17 exception table). The 500 mm OD and 89 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30256UTG list two speeds, 630 and 900 r/min?", "a": "The lower figure, 630 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30256UTG at 900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30256UTG mean?", "a": "Suffix reading on 30256UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30256UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30256utg", "＊30256utg", "30256UTG" ], "locale_variants": {} }, { "sku": "32256UTG", "brand": "NTN", "manufacturer_designation": "NTN 32256UTG", "series": "32200-series", "type": "tapered_roller", "d_mm": 280, "D_mm": 500, "B_mm": 137, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2530, "static_load_kN": 3500, "fatigue_load_limit_kN": 283, "limiting_speed_rpm": 630, "max_rpm": 630, "speed_oil_rpm": 900, "weight_g": 110000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32256UTG denotes the heavy-section 32200 family of metric tapered roller bearings, 280 mm bore, 500 mm outside diameter and 137 mm assembled width T (11.024 × 19.685 × 5.394 in) to the ISO 355 boundary plan. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32256UTG resolves to 280 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32256UTG, not only the raceway. The 110.0 mm section height over the 280 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Open 4T bearings need application seals; without them the grease at the cone rib of 32256UTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 280 mm bore the 32256UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2530 kN C level.", "The heavy-section 32200 family at 280 mm bore (500×137 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 900 r/min oil ceiling.", "Grease packs must leave free volume in the 137 mm-wide set; over-greasing a paired bearing churning at the 900 r/min oil-band speed raises temperature and destroys the preload setting.", "Minimum load matters at high speed: an unloaded 32256UTG at a large fraction of 630 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 280 mm shoulder geometry, because retrofitting flips the cups.", "The 2530/3500 kN ratings and 283 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32256UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32256UTG?", "a": "32256UTG is a metric 4T tapered roller bearing to ISO 355: 280 mm bore, 500 mm outside diameter and 137 mm assembled width T (11.024 × 19.685 × 5.394 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2530 kN, C0 3500 kN, Pu 283 kN, grease limiting speed 630 r/min, oil speed 900 r/min, mass about 110000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32256UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32256UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32256UTG designation encode the 280 mm bore?", "a": "last two digits 56 are the ISO bore code, ×5 = 280 mm (codes 00–03 use the 10/12/15/17 exception table). The 500 mm OD and 137 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32256UTG list two speeds, 630 and 900 r/min?", "a": "The lower figure, 630 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32256UTG at 900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32256UTG mean?", "a": "Suffix reading on 32256UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32256UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32256utg", "＊32256utg", "32256UTG" ], "locale_variants": {} }, { "sku": "32960XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32960XUUTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 300, "D_mm": 420, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1290, "static_load_kN": 2090, "fatigue_load_limit_kN": 173, "limiting_speed_rpm": 720, "max_rpm": 720, "speed_oil_rpm": 1000, "weight_g": 31400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32960XUUTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 300×420 mm ISO 355 envelope, with 76 mm overall assembled width T. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 300 mm; 420 mm OD and 76 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32960XUUTG, not only the raceway. The two speed columns differ by a factor of .72 (grease/limiting 720 vs oil 1,000 r/min); heat generation at the cone rib decides which lubrication a real 32960XUUTG arrangement can sustain. Open 4T bearings need application seals; without them the grease at the cone rib of 32960XUUTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 300 mm bore the 32960XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1290 kN C level.", "The thin 76 mm section of 32960XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 300 mm bore smears the roller ends against the rib.", "Open 32960XUUTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 720 r/min grease figure is meaningless once water reaches the cone rib.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32960XUUTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 300 mm shoulder geometry, because retrofitting flips the cups.", "The 1290/2090 kN ratings and 173 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32960XUUTG (ISO 355 3FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32960XUUTG?", "a": "32960XUUTG is a metric 4T tapered roller bearing to ISO 355: 300 mm bore, 420 mm outside diameter and 76 mm assembled width T (11.811 × 16.535 × 2.992 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1290 kN, C0 2090 kN, Pu 173 kN, grease limiting speed 720 r/min, oil speed 1,000 r/min, mass about 31400 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32960XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32960XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32960XUUTG designation encode the 300 mm bore and what is 3FD?", "a": "last two digits 60 are the ISO bore code, ×5 = 300 mm (codes 00–03 use the 10/12/15/17 exception table). The 420 mm OD and 76 mm assembled T follow the ISO 355 dimension-series plan. 3FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32960XUUTG list two speeds, 720 and 1,000 r/min?", "a": "The lower figure, 720 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32960XUUTG at 1,000 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32960XUUTG mean?", "a": "Suffix reading on 32960XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32960XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32960xuutg", "3fd", "＊32960xuutg", "32960XUUTG" ], "locale_variants": {} }, { "sku": "32060XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32060XUUTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 300, "D_mm": 460, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1920, "static_load_kN": 2830, "fatigue_load_limit_kN": 232, "limiting_speed_rpm": 680, "max_rpm": 680, "speed_oil_rpm": 960, "weight_g": 57200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 300 mm shaft with a thrust component, NTN lists 32060XUUTG, a metric 4T tapered roller bearing of 1920 kN C and 2830 kN C0 inside the 460 mm OD, 100 mm-wide assembled set. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32060XUUTG by the metric ISO 355 number (ISO series abbreviation 4GD): 300 mm bore, 460 mm OD. Suffix reading on 32060XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles. Catalogue mass of the 32060XUUTG set is 57200 g (2.252 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Fillet radii must clear the ring chamfers of the 460 mm cup and 300 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 300 mm bore the 32060XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1920 kN C level.", "The thin 100 mm section of 32060XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 300 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 100 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 32060XUUTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 680 r/min grease figure is meaningless once water reaches the cone rib.", "ISO 355 makes the 300×460 mm envelope interchangeable but not the ratings: NTN prints 1920/2830 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 1920/2830 kN ratings and 232 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32060XUUTG (ISO 355 4GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32060XUUTG?", "a": "32060XUUTG is a metric 4T tapered roller bearing to ISO 355: 300 mm bore, 460 mm outside diameter and 100 mm assembled width T (11.811 × 18.11 × 3.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1920 kN, C0 2830 kN, Pu 232 kN, grease limiting speed 680 r/min, oil speed 960 r/min, mass about 57200 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32060XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32060XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32060XUUTG designation encode the 300 mm bore and what is 4GD?", "a": "last two digits 60 are the ISO bore code, ×5 = 300 mm (codes 00–03 use the 10/12/15/17 exception table). The 460 mm OD and 100 mm assembled T follow the ISO 355 dimension-series plan. 4GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32060XUUTG list two speeds, 680 and 960 r/min?", "a": "The lower figure, 680 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32060XUUTG at 960 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32060XUUTG mean?", "a": "Suffix reading on 32060XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32060XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32060xuutg", "4gd", "＊32060xuutg", "32060XUUTG" ], "locale_variants": {} }, { "sku": "30260UTG", "brand": "NTN", "manufacturer_designation": "NTN 30260UTG", "series": "30200-series", "type": "tapered_roller", "d_mm": 300, "D_mm": 540, "B_mm": 96, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1820, "static_load_kN": 2220, "fatigue_load_limit_kN": 176, "limiting_speed_rpm": 580, "max_rpm": 580, "speed_oil_rpm": 830, "weight_g": 83500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 300 mm shaft with a thrust component, NTN lists 30260UTG, a metric 4T tapered roller bearing of 1820 kN C and 2220 kN C0 inside the 540 mm OD, 96 mm-wide assembled set. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 30260UTG by the metric ISO 355 number: 300 mm bore, 540 mm OD. NTN grades 4T metric bearings as open bearings without integral seals; at 300 mm bore the application supplies the seals and the grease fill or oil supply to the ISO 355 assembly. The 120.0 mm section height over the 300 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 300 mm pair is misadjusted and the 96 mm T set will edge-load in service.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 300 mm bore the 30260UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1820 kN C level.", "The standard-section 30200 family at 300 mm bore (540×96 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 830 r/min oil ceiling.", "The 120.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30260UTG or the ring will bottom out on the radius instead of the shoulder face.", "Do not confuse T (96 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 120.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30260UTG or the ring will bottom out on the radius instead of the shoulder face.", "The 1820/2220 kN ratings and 176 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30260UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30260UTG?", "a": "30260UTG is a metric 4T tapered roller bearing to ISO 355: 300 mm bore, 540 mm outside diameter and 96 mm assembled width T (11.811 × 21.26 × 3.78 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1820 kN, C0 2220 kN, Pu 176 kN, grease limiting speed 580 r/min, oil speed 830 r/min, mass about 83500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30260UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30260UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30260UTG designation encode the 300 mm bore?", "a": "last two digits 60 are the ISO bore code, ×5 = 300 mm (codes 00–03 use the 10/12/15/17 exception table). The 540 mm OD and 96 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30260UTG list two speeds, 580 and 830 r/min?", "a": "The lower figure, 580 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30260UTG at 830 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30260UTG mean?", "a": "Suffix reading on 30260UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30260UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30260utg", "＊30260utg", "30260UTG" ], "locale_variants": {} }, { "sku": "32260UTG", "brand": "NTN", "manufacturer_designation": "NTN 32260UTG", "series": "32200-series", "type": "tapered_roller", "d_mm": 300, "D_mm": 540, "B_mm": 149, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2950, "static_load_kN": 4100, "fatigue_load_limit_kN": 325, "limiting_speed_rpm": 580, "max_rpm": 580, "speed_oil_rpm": 830, "weight_g": 140000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32260UTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 300×540 mm ISO 355 envelope, with 149 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32260UTG by the metric ISO 355 number: 300 mm bore, 540 mm OD. NTN grades 4T metric bearings as open bearings without integral seals; at 300 mm bore the application supplies the seals and the grease fill or oil supply to the ISO 355 assembly. Selection: C 2950 kN against C0 4100 kN gives a C0/C ratio of 1.39 for the 300 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. When pairing 32260UTG with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 300 mm bore the 32260UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2950 kN C level.", "The heavy-section 32200 family at 300 mm bore (540×149 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 830 r/min oil ceiling.", "Replacing one half of an adjusted pair without resetting end play negates the 149 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Minimum load matters at high speed: an unloaded 32260UTG at a large fraction of 580 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 120.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32260UTG or the ring will bottom out on the radius instead of the shoulder face.", "The 2950/4100 kN ratings and 325 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32260UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32260UTG?", "a": "32260UTG is a metric 4T tapered roller bearing to ISO 355: 300 mm bore, 540 mm outside diameter and 149 mm assembled width T (11.811 × 21.26 × 5.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2950 kN, C0 4100 kN, Pu 325 kN, grease limiting speed 580 r/min, oil speed 830 r/min, mass about 140000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32260UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32260UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32260UTG designation encode the 300 mm bore?", "a": "last two digits 60 are the ISO bore code, ×5 = 300 mm (codes 00–03 use the 10/12/15/17 exception table). The 540 mm OD and 149 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32260UTG list two speeds, 580 and 830 r/min?", "a": "The lower figure, 580 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32260UTG at 830 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32260UTG mean?", "a": "Suffix reading on 32260UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32260UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32260utg", "＊32260utg", "32260UTG" ], "locale_variants": {} }, { "sku": "32964E1", "brand": "NTN", "manufacturer_designation": "NTN 32964E1", "series": "32900-series", "type": "tapered_roller", "d_mm": 320, "D_mm": 440, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 955, "static_load_kN": 1880, "fatigue_load_limit_kN": 153, "limiting_speed_rpm": 670, "max_rpm": 670, "speed_oil_rpm": 900, "weight_g": 33200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32964E1 in the extra-light thin-section 32900 family: 320 mm bore, 440 mm cup OD, 76 mm T, with a grease limiting speed of 670 r/min and an oil-lubricated ceiling of 900 r/min. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 320 mm; 440 mm OD and 76 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Speed planning uses both catalogue columns: grease 670 r/min is the cage/rib mechanical ceiling for 32964E1, oil 900 r/min is available with circulating oil — a 230 r/min margin at this size. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 32964E1; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 320 mm bore the 32964E1 set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 955 kN C level.", "The thin 76 mm section of 32964E1 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 320 mm bore smears the roller ends against the rib.", "ISO 355 makes the 320×440 mm envelope interchangeable but not the ratings: NTN prints 955/1880 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 320 mm shoulder geometry, because retrofitting flips the cups.", "Replacing one half of an adjusted pair without resetting end play negates the 76 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 955/1880 kN ratings and 153 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32964E1; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32964E1?", "a": "32964E1 is a metric 4T tapered roller bearing to ISO 355: 320 mm bore, 440 mm outside diameter and 76 mm assembled width T (12.598 × 17.323 × 2.992 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 955 kN, C0 1880 kN, Pu 153 kN, grease limiting speed 670 r/min, oil speed 900 r/min, mass about 33200 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32964E1?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32964E1); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32964E1 designation encode the 320 mm bore?", "a": "last two digits E1 are the ISO bore code, ×5 = 320 mm (codes 00–03 use the 10/12/15/17 exception table). The 440 mm OD and 76 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32964E1 list two speeds, 670 and 900 r/min?", "a": "The lower figure, 670 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32964E1 at 900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32964E1 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32964E1", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32964e1", "⃝32964e1", "32964E1" ], "locale_variants": {} }, { "sku": "32964XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32964XUUTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 320, "D_mm": 440, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1300, "static_load_kN": 2150, "fatigue_load_limit_kN": 176, "limiting_speed_rpm": 670, "max_rpm": 670, "speed_oil_rpm": 960, "weight_g": 32800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 320 mm shaft with a thrust component, NTN lists 32964XUUTG, a metric 4T tapered roller bearing of 1300 kN C and 2150 kN C0 inside the 440 mm OD, 76 mm-wide assembled set. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 320 mm; 440 mm OD and 76 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The 60.0 mm radial section carries the roller complement across the 320–440 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. Grease relubrication at 670 r/min limiting speed targets the rib contact; if the drive needs 960 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. Mount the 320 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32964XUUTG.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 320 mm bore the 32964XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1300 kN C level.", "The thin 76 mm section of 32964XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 320 mm bore smears the roller ends against the rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 320 mm shoulder geometry, because retrofitting flips the cups.", "The 60.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32964XUUTG or the ring will bottom out on the radius instead of the shoulder face.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32964XUUTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "The 1300/2150 kN ratings and 176 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32964XUUTG (ISO 355 3FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32964XUUTG?", "a": "32964XUUTG is a metric 4T tapered roller bearing to ISO 355: 320 mm bore, 440 mm outside diameter and 76 mm assembled width T (12.598 × 17.323 × 2.992 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1300 kN, C0 2150 kN, Pu 176 kN, grease limiting speed 670 r/min, oil speed 960 r/min, mass about 32800 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32964XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32964XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32964XUUTG designation encode the 320 mm bore and what is 3FD?", "a": "last two digits 64 are the ISO bore code, ×5 = 320 mm (codes 00–03 use the 10/12/15/17 exception table). The 440 mm OD and 76 mm assembled T follow the ISO 355 dimension-series plan. 3FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32964XUUTG list two speeds, 670 and 960 r/min?", "a": "The lower figure, 670 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32964XUUTG at 960 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32964XUUTG mean?", "a": "Suffix reading on 32964XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32964XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32964xuutg", "3fd", "＊32964xuutg", "32964XUUTG" ], "locale_variants": {} }, { "sku": "32064XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32064XUUTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 320, "D_mm": 480, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1940, "static_load_kN": 2940, "fatigue_load_limit_kN": 237, "limiting_speed_rpm": 630, "max_rpm": 630, "speed_oil_rpm": 900, "weight_g": 60200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32064XUUTG denotes the low-section 32000 family tuned for low friction of metric tapered roller bearings, 320 mm bore, 480 mm outside diameter and 100 mm assembled width T (12.598 × 18.898 × 3.937 in) to the ISO 355 boundary plan. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32064XUUTG by the metric ISO 355 number (ISO series abbreviation 4GD): 320 mm bore, 480 mm OD. Suffix reading on 32064XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles. Selection: C 1940 kN against C0 2940 kN gives a C0/C ratio of 1.52 for the 320 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. When pairing 32064XUUTG with a second tapered bearing, keep the matched arrangement clean: a single stray grit particle between cup and housing changes preload faster than the adjustment range can correct.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 320 mm bore the 32064XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1940 kN C level.", "The thin 100 mm section of 32064XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 320 mm bore smears the roller ends against the rib.", "Do not confuse T (100 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 320 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "ISO 355 makes the 320×480 mm envelope interchangeable but not the ratings: NTN prints 1940/2940 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 1940/2940 kN ratings and 237 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32064XUUTG (ISO 355 4GD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32064XUUTG?", "a": "32064XUUTG is a metric 4T tapered roller bearing to ISO 355: 320 mm bore, 480 mm outside diameter and 100 mm assembled width T (12.598 × 18.898 × 3.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1940 kN, C0 2940 kN, Pu 237 kN, grease limiting speed 630 r/min, oil speed 900 r/min, mass about 60200 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32064XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32064XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32064XUUTG designation encode the 320 mm bore and what is 4GD?", "a": "last two digits 64 are the ISO bore code, ×5 = 320 mm (codes 00–03 use the 10/12/15/17 exception table). The 480 mm OD and 100 mm assembled T follow the ISO 355 dimension-series plan. 4GD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32064XUUTG list two speeds, 630 and 900 r/min?", "a": "The lower figure, 630 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32064XUUTG at 900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32064XUUTG mean?", "a": "Suffix reading on 32064XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32064XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32064xuutg", "4gd", "＊32064xuutg", "32064XUUTG" ], "locale_variants": {} }, { "sku": "30264UTG", "brand": "NTN", "manufacturer_designation": "NTN 30264UTG", "series": "30200-series", "type": "tapered_roller", "d_mm": 320, "D_mm": 580, "B_mm": 104, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2130, "static_load_kN": 2580, "fatigue_load_limit_kN": 201, "limiting_speed_rpm": 540, "max_rpm": 540, "speed_oil_rpm": 770, "weight_g": 100000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 30264UTG in the standard-section 30200 family: 320 mm bore, 580 mm cup OD, 104 mm T, with a grease limiting speed of 540 r/min and an oil-lubricated ceiling of 770 r/min. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 320×580 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. The 130.0 mm section height over the 320 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Mount the 320 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 30264UTG.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 320 mm bore the 30264UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2130 kN C level.", "The standard-section 30200 family at 320 mm bore (580×104 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 770 r/min oil ceiling.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 320 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 130.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 30264UTG or the ring will bottom out on the radius instead of the shoulder face.", "Replacing one half of an adjusted pair without resetting end play negates the 104 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 2130/2580 kN ratings and 201 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30264UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 30264UTG?", "a": "30264UTG is a metric 4T tapered roller bearing to ISO 355: 320 mm bore, 580 mm outside diameter and 104 mm assembled width T (12.598 × 22.835 × 4.094 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2130 kN, C0 2580 kN, Pu 201 kN, grease limiting speed 540 r/min, oil speed 770 r/min, mass about 100000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 30264UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (30264UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 30264UTG designation encode the 320 mm bore?", "a": "last two digits 64 are the ISO bore code, ×5 = 320 mm (codes 00–03 use the 10/12/15/17 exception table). The 580 mm OD and 104 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 30264UTG list two speeds, 540 and 770 r/min?", "a": "The lower figure, 540 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 30264UTG at 770 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 30264UTG mean?", "a": "Suffix reading on 30264UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "30264UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "30264utg", "＊30264utg", "30264UTG" ], "locale_variants": {} }, { "sku": "32264UTG", "brand": "NTN", "manufacturer_designation": "NTN 32264UTG", "series": "32200-series", "type": "tapered_roller", "d_mm": 320, "D_mm": 580, "B_mm": 159, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 3350, "static_load_kN": 4650, "fatigue_load_limit_kN": 360, "limiting_speed_rpm": 540, "max_rpm": 540, "speed_oil_rpm": 770, "weight_g": 170000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32264UTG belongs to the NTN metric 4T tapered roller range (heavy-section 32200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32264UTG by the metric ISO 355 number: 320 mm bore, 580 mm OD. NTN grades 4T metric bearings as open bearings without integral seals; at 320 mm bore the application supplies the seals and the grease fill or oil supply to the ISO 355 assembly. The two speed columns differ by a factor of .70 (grease/limiting 540 vs oil 770 r/min); heat generation at the cone rib decides which lubrication a real 32264UTG arrangement can sustain. Mount the 320 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32264UTG.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 320 mm bore the 32264UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 3350 kN C level.", "The heavy-section 32200 family at 320 mm bore (580×159 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 770 r/min oil ceiling.", "Never fit the 320 mm cone by hammering the 580 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume in the 159 mm-wide set; over-greasing a paired bearing churning at the 770 r/min oil-band speed raises temperature and destroys the preload setting.", "The 130.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32264UTG or the ring will bottom out on the radius instead of the shoulder face.", "The 3350/4650 kN ratings and 360 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32264UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32264UTG?", "a": "32264UTG is a metric 4T tapered roller bearing to ISO 355: 320 mm bore, 580 mm outside diameter and 159 mm assembled width T (12.598 × 22.835 × 6.26 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 3350 kN, C0 4650 kN, Pu 360 kN, grease limiting speed 540 r/min, oil speed 770 r/min, mass about 170000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32264UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32264UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32264UTG designation encode the 320 mm bore?", "a": "last two digits 64 are the ISO bore code, ×5 = 320 mm (codes 00–03 use the 10/12/15/17 exception table). The 580 mm OD and 159 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32264UTG list two speeds, 540 and 770 r/min?", "a": "The lower figure, 540 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32264UTG at 770 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32264UTG mean?", "a": "Suffix reading on 32264UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32264UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=173", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32264utg", "＊32264utg", "32264UTG" ], "locale_variants": {} }, { "sku": "32968E1", "brand": "NTN", "manufacturer_designation": "NTN 32968E1", "series": "32900-series", "type": "tapered_roller", "d_mm": 340, "D_mm": 460, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1010, "static_load_kN": 1980, "fatigue_load_limit_kN": 159, "limiting_speed_rpm": 630, "max_rpm": 630, "speed_oil_rpm": 900, "weight_g": 34000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32968E1 is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 340×460 mm ISO 355 envelope, with 76 mm overall assembled width T. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 340×460 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. At 1010 kN C the bearing offers about 3.0 kN of dynamic capacity per millimetre of the 340 mm bore — compare any substitution on this ratio and the 76 mm assembled T, not on bore alone. The 60.0 mm section height over the 340 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 340 mm pair is misadjusted and the 76 mm T set will edge-load in service.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 340 mm bore the 32968E1 set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1010 kN C level.", "The thin 76 mm section of 32968E1 is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 340 mm bore smears the roller ends against the rib.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 340 mm shoulder geometry, because retrofitting flips the cups.", "Never fit the 340 mm cone by hammering the 460 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 32968E1 units have no seals: a wheel-hub or gearbox application needs external sealing or the 630 r/min grease figure is meaningless once water reaches the cone rib.", "The 1010/1980 kN ratings and 159 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32968E1; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32968E1?", "a": "32968E1 is a metric 4T tapered roller bearing to ISO 355: 340 mm bore, 460 mm outside diameter and 76 mm assembled width T (13.386 × 18.11 × 2.992 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1010 kN, C0 1980 kN, Pu 159 kN, grease limiting speed 630 r/min, oil speed 900 r/min, mass about 34000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32968E1?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32968E1); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32968E1 designation encode the 340 mm bore?", "a": "last two digits E1 are the ISO bore code, ×5 = 340 mm (codes 00–03 use the 10/12/15/17 exception table). The 460 mm OD and 76 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32968E1 list two speeds, 630 and 900 r/min?", "a": "The lower figure, 630 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32968E1 at 900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32968E1 mean?", "a": "It is the basic open 4T execution — steel cage, adjusted mounting, no seal or feature suffix. NTN uses U for the uprated design, UTG for ULTAGE large-bearing specs, X for the ISO boundary section, and C/CA/D/A for contact-angle or internal-design variants; all are separate order numbers." } ], "cross_ref": [ { "equiv_sku": "32968E1", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32968e1", "○32968e1", "32968E1" ], "locale_variants": {} }, { "sku": "32968XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32968XUUTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 340, "D_mm": 460, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1340, "static_load_kN": 2270, "fatigue_load_limit_kN": 183, "limiting_speed_rpm": 630, "max_rpm": 630, "speed_oil_rpm": 900, "weight_g": 34500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32968XUUTG denotes the extra-light thin-section 32900 family of metric tapered roller bearings, 340 mm bore, 460 mm outside diameter and 76 mm assembled width T (13.386 × 18.11 × 2.992 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 340 mm; 460 mm OD and 76 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. Suffix reading on 32968XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles. Catalogue mass of the 32968XUUTG set is 34500 g (1.358 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32968XUUTG arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 340 mm bore the 32968XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1340 kN C level.", "The thin 76 mm section of 32968XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 340 mm bore smears the roller ends against the rib.", "Grease packs must leave free volume in the 76 mm-wide set; over-greasing a paired bearing churning at the 900 r/min oil-band speed raises temperature and destroys the preload setting.", "Open 32968XUUTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 630 r/min grease figure is meaningless once water reaches the cone rib.", "ISO 355 makes the 340×460 mm envelope interchangeable but not the ratings: NTN prints 1340/2270 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "The 1340/2270 kN ratings and 183 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32968XUUTG (ISO 355 4FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32968XUUTG?", "a": "32968XUUTG is a metric 4T tapered roller bearing to ISO 355: 340 mm bore, 460 mm outside diameter and 76 mm assembled width T (13.386 × 18.11 × 2.992 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1340 kN, C0 2270 kN, Pu 183 kN, grease limiting speed 630 r/min, oil speed 900 r/min, mass about 34500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32968XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32968XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32968XUUTG designation encode the 340 mm bore and what is 4FD?", "a": "last two digits 68 are the ISO bore code, ×5 = 340 mm (codes 00–03 use the 10/12/15/17 exception table). The 460 mm OD and 76 mm assembled T follow the ISO 355 dimension-series plan. 4FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32968XUUTG list two speeds, 630 and 900 r/min?", "a": "The lower figure, 630 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32968XUUTG at 900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32968XUUTG mean?", "a": "Suffix reading on 32968XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32968XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32968xuutg", "4fd", "＊32968xuutg", "32968XUUTG" ], "locale_variants": {} }, { "sku": "32068UTG", "brand": "NTN", "manufacturer_designation": "NTN 32068UTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 340, "D_mm": 520, "B_mm": 112, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2120, "static_load_kN": 3150, "fatigue_load_limit_kN": 249, "limiting_speed_rpm": 590, "max_rpm": 590, "speed_oil_rpm": 840, "weight_g": 78500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 340 mm shaft with a thrust component, NTN lists 32068UTG, a metric 4T tapered roller bearing of 2120 kN C and 3150 kN C0 inside the 520 mm OD, 112 mm-wide assembled set. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 340×520 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. Individually mounted, 32068UTG takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Selection: C 2120 kN against C0 3150 kN gives a C0/C ratio of 1.49 for the 340 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Fillet radii must clear the ring chamfers of the 520 mm cup and 340 mm cone; use undercut shoulders so the rings seat fully rather than bridging on a shaft radius.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 340 mm bore the 32068UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2120 kN C level.", "The thin 112 mm section of 32068UTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 340 mm bore smears the roller ends against the rib.", "Grease packs must leave free volume in the 112 mm-wide set; over-greasing a paired bearing churning at the 840 r/min oil-band speed raises temperature and destroys the preload setting.", "Replacing one half of an adjusted pair without resetting end play negates the 112 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never fit the 340 mm cone by hammering the 520 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 2120/3150 kN ratings and 249 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32068UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32068UTG?", "a": "32068UTG is a metric 4T tapered roller bearing to ISO 355: 340 mm bore, 520 mm outside diameter and 112 mm assembled width T (13.386 × 20.472 × 4.409 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2120 kN, C0 3150 kN, Pu 249 kN, grease limiting speed 590 r/min, oil speed 840 r/min, mass about 78500 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32068UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32068UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32068UTG designation encode the 340 mm bore?", "a": "last two digits 68 are the ISO bore code, ×5 = 340 mm (codes 00–03 use the 10/12/15/17 exception table). The 520 mm OD and 112 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32068UTG list two speeds, 590 and 840 r/min?", "a": "The lower figure, 590 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32068UTG at 840 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32068UTG mean?", "a": "Suffix reading on 32068UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32068UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32068utg", "＊32068utg", "32068UTG" ], "locale_variants": {} }, { "sku": "32972XUUTG", "brand": "NTN", "manufacturer_designation": "NTN 32972XUUTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 360, "D_mm": 480, "B_mm": 76, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1350, "static_load_kN": 2330, "fatigue_load_limit_kN": 185, "limiting_speed_rpm": 590, "max_rpm": 590, "speed_oil_rpm": 840, "weight_g": 36300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32972XUUTG belongs to the NTN metric 4T tapered roller range (extra-light thin-section 32900 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation, 4FD, which is the maker-neutral cross-reference for the 360×480 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32972XUUTG, not only the raceway. The two speed columns differ by a factor of .70 (grease/limiting 590 vs oil 840 r/min); heat generation at the cone rib decides which lubrication a real 32972XUUTG arrangement can sustain. Mount the 360 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32972XUUTG.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "false brinelling on a stationary paired set exposed to external vibration" ], "pitfalls": [ "At 360 mm bore the 32972XUUTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1350 kN C level.", "The thin 76 mm section of 32972XUUTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 360 mm bore smears the roller ends against the rib.", "Do not confuse T (76 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32972XUUTG by size alone can deliver the wrong contact-angle execution for a pinion position.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 360 mm shoulder geometry, because retrofitting flips the cups.", "The 1350/2330 kN ratings and 185 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32972XUUTG (ISO 355 4FD); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32972XUUTG?", "a": "32972XUUTG is a metric 4T tapered roller bearing to ISO 355: 360 mm bore, 480 mm outside diameter and 76 mm assembled width T (14.173 × 18.898 × 2.992 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1350 kN, C0 2330 kN, Pu 185 kN, grease limiting speed 590 r/min, oil speed 840 r/min, mass about 36300 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32972XUUTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32972XUUTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32972XUUTG designation encode the 360 mm bore and what is 4FD?", "a": "last two digits 72 are the ISO bore code, ×5 = 360 mm (codes 00–03 use the 10/12/15/17 exception table). The 480 mm OD and 76 mm assembled T follow the ISO 355 dimension-series plan. 4FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark." }, { "q": "Why does 32972XUUTG list two speeds, 590 and 840 r/min?", "a": "The lower figure, 590 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32972XUUTG at 840 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32972XUUTG mean?", "a": "Suffix reading on 32972XUUTG: the XUUTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; XU combines the X ISO boundary section with the U uprated internal design; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32972XUUTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32972xuutg", "4fd", "＊32972xuutg", "32972XUUTG" ], "locale_variants": {} }, { "sku": "32072UTG", "brand": "NTN", "manufacturer_designation": "NTN 32072UTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 360, "D_mm": 540, "B_mm": 112, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2230, "static_load_kN": 3300, "fatigue_load_limit_kN": 258, "limiting_speed_rpm": 550, "max_rpm": 550, "speed_oil_rpm": 780, "weight_g": 83000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32072UTG in the low-section 32000 family tuned for low friction: 360 mm bore, 540 mm cup OD, 112 mm T, with a grease limiting speed of 550 r/min and an oil-lubricated ceiling of 780 r/min. Digit by digit, the bare number identifies the low-section 32000 family tuned for low friction and a bore code resolving to 360 mm; 540 mm OD and 112 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. Grease relubrication at 550 r/min limiting speed targets the rib contact; if the drive needs 780 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. With a rotating shaft a m6/n6 shaft seat and a press-fit cup are typical catalogue practice for 32072UTG; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.", "applications": [ "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 360 mm bore the 32072UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2230 kN C level.", "The thin 112 mm section of 32072UTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 360 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 112 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 112 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 112 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 2230/3300 kN ratings and 258 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32072UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32072UTG?", "a": "32072UTG is a metric 4T tapered roller bearing to ISO 355: 360 mm bore, 540 mm outside diameter and 112 mm assembled width T (14.173 × 21.26 × 4.409 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2230 kN, C0 3300 kN, Pu 258 kN, grease limiting speed 550 r/min, oil speed 780 r/min, mass about 83000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32072UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32072UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32072UTG designation encode the 360 mm bore?", "a": "last two digits 72 are the ISO bore code, ×5 = 360 mm (codes 00–03 use the 10/12/15/17 exception table). The 540 mm OD and 112 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32072UTG list two speeds, 550 and 780 r/min?", "a": "The lower figure, 550 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32072UTG at 780 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32072UTG mean?", "a": "Suffix reading on 32072UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32072UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32072utg", "＊32072utg", "32072UTG" ], "locale_variants": {} }, { "sku": "32976UTG", "brand": "NTN", "manufacturer_designation": "NTN 32976UTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 380, "D_mm": 520, "B_mm": 87, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1460, "static_load_kN": 2500, "fatigue_load_limit_kN": 194, "limiting_speed_rpm": 550, "max_rpm": 550, "speed_oil_rpm": 790, "weight_g": 51300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "The NTN 2203E table prints 32976UTG in the extra-light thin-section 32900 family: 380 mm bore, 520 mm cup OD, 87 mm T, with a grease limiting speed of 550 r/min and an oil-lubricated ceiling of 790 r/min. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32976UTG resolves to 380 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. 2203E lists two speed ceilings for 32976UTG: 550 r/min with grease lubrication (the limiting speed) and 790 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. The two speed columns differ by a factor of .70 (grease/limiting 550 vs oil 790 r/min); heat generation at the cone rib decides which lubrication a real 32976UTG arrangement can sustain. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 380 mm pair is misadjusted and the 87 mm T set will edge-load in service.", "applications": [ "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 380 mm bore the 32976UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1460 kN C level.", "The thin 87 mm section of 32976UTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 380 mm bore smears the roller ends against the rib.", "Replacing one half of an adjusted pair without resetting end play negates the 87 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never fit the 380 mm cone by hammering the 520 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume in the 87 mm-wide set; over-greasing a paired bearing churning at the 790 r/min oil-band speed raises temperature and destroys the preload setting.", "The 1460/2500 kN ratings and 194 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32976UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32976UTG?", "a": "32976UTG is a metric 4T tapered roller bearing to ISO 355: 380 mm bore, 520 mm outside diameter and 87 mm assembled width T (14.961 × 20.472 × 3.425 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1460 kN, C0 2500 kN, Pu 194 kN, grease limiting speed 550 r/min, oil speed 790 r/min, mass about 51300 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32976UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32976UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32976UTG designation encode the 380 mm bore?", "a": "last two digits 76 are the ISO bore code, ×5 = 380 mm (codes 00–03 use the 10/12/15/17 exception table). The 520 mm OD and 87 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32976UTG list two speeds, 550 and 790 r/min?", "a": "The lower figure, 550 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32976UTG at 790 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32976UTG mean?", "a": "Suffix reading on 32976UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32976UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32976utg", "＊32976utg", "32976UTG" ], "locale_variants": {} }, { "sku": "32076UTG", "brand": "NTN", "manufacturer_designation": "NTN 32076UTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 380, "D_mm": 560, "B_mm": 112, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2460, "static_load_kN": 3800, "fatigue_load_limit_kN": 292, "limiting_speed_rpm": 520, "max_rpm": 520, "speed_oil_rpm": 740, "weight_g": 89100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32076UTG is the NTN 4T catalogue entry for a 380×560×112 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Digit by digit, the bare number identifies the low-section 32000 family tuned for low friction and a bore code resolving to 380 mm; 560 mm OD and 112 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The pressed-steel cage and surface-finished roller ends are standard 4T execution; ULTAGE-marked variants use upgraded material and internal geometry aimed at longer rating life with the same ISO 355 envelope. The 90.0 mm section height over the 380 mm bore positions the load centre; axial location of the pair depends on that contact line, so spacer faces must be square within the P0 tolerance of the bearing. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 32076UTG arrangement has run in, because initial seat seating relaxes the set preload slightly.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "edge loading when shaft deflection exceeds the few arc-minutes of misalignment the adjusted pair allows" ], "pitfalls": [ "At 380 mm bore the 32076UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2460 kN C level.", "The thin 112 mm section of 32076UTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 380 mm bore smears the roller ends against the rib.", "Never fit the 380 mm cone by hammering the 560 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 32076UTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 520 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 112 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 2460/3800 kN ratings and 292 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32076UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32076UTG?", "a": "32076UTG is a metric 4T tapered roller bearing to ISO 355: 380 mm bore, 560 mm outside diameter and 112 mm assembled width T (14.961 × 22.047 × 4.409 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2460 kN, C0 3800 kN, Pu 292 kN, grease limiting speed 520 r/min, oil speed 740 r/min, mass about 89100 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32076UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32076UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32076UTG designation encode the 380 mm bore?", "a": "last two digits 76 are the ISO bore code, ×5 = 380 mm (codes 00–03 use the 10/12/15/17 exception table). The 560 mm OD and 112 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32076UTG list two speeds, 520 and 740 r/min?", "a": "The lower figure, 520 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32076UTG at 740 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32076UTG mean?", "a": "Suffix reading on 32076UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32076UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32076utg", "＊32076utg", "32076UTG" ], "locale_variants": {} }, { "sku": "32980UTG", "brand": "NTN", "manufacturer_designation": "NTN 32980UTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 400, "D_mm": 540, "B_mm": 87, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1530, "static_load_kN": 2710, "fatigue_load_limit_kN": 207, "limiting_speed_rpm": 520, "max_rpm": 520, "speed_oil_rpm": 740, "weight_g": 54000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 32980UTG denotes the extra-light thin-section 32900 family of metric tapered roller bearings, 400 mm bore, 540 mm outside diameter and 87 mm assembled width T (15.748 × 21.26 × 3.425 in) to the ISO 355 boundary plan. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 400 mm; 540 mm OD and 87 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32980UTG, not only the raceway. The fatigue load limit Pu printed for 32980UTG is 207 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 400 mm pair is misadjusted and the 87 mm T set will edge-load in service.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 400 mm bore the 32980UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1530 kN C level.", "The thin 87 mm section of 32980UTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 400 mm bore smears the roller ends against the rib.", "Never fit the 400 mm cone by hammering the 540 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never fit the 400 mm cone by hammering the 540 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 400 mm shoulder geometry, because retrofitting flips the cups.", "The 1530/2710 kN ratings and 207 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32980UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32980UTG?", "a": "32980UTG is a metric 4T tapered roller bearing to ISO 355: 400 mm bore, 540 mm outside diameter and 87 mm assembled width T (15.748 × 21.26 × 3.425 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1530 kN, C0 2710 kN, Pu 207 kN, grease limiting speed 520 r/min, oil speed 740 r/min, mass about 54000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32980UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32980UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32980UTG designation encode the 400 mm bore?", "a": "last two digits 80 are the ISO bore code, ×5 = 400 mm (codes 00–03 use the 10/12/15/17 exception table). The 540 mm OD and 87 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32980UTG list two speeds, 520 and 740 r/min?", "a": "The lower figure, 520 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32980UTG at 740 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32980UTG mean?", "a": "Suffix reading on 32980UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32980UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32980utg", "＊32980utg", "32980UTG" ], "locale_variants": {} }, { "sku": "32080UTG", "brand": "NTN", "manufacturer_designation": "NTN 32080UTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 400, "D_mm": 600, "B_mm": 125, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2790, "static_load_kN": 4250, "fatigue_load_limit_kN": 320, "limiting_speed_rpm": 490, "max_rpm": 490, "speed_oil_rpm": 700, "weight_g": 110000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32080UTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 400×600 mm ISO 355 envelope, with 125 mm overall assembled width T. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32080UTG resolves to 400 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32080UTG cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The two speed columns differ by a factor of .70 (grease/limiting 490 vs oil 700 r/min); heat generation at the cone rib decides which lubrication a real 32080UTG arrangement can sustain. Open 4T bearings need application seals; without them the grease at the cone rib of 32080UTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage damage from a mounting blow delivered through the roller complement instead of the ring face", "water-induced pitting when the open bearing is exposed to washdown without external seals" ], "pitfalls": [ "At 400 mm bore the 32080UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2790 kN C level.", "The thin 125 mm section of 32080UTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 400 mm bore smears the roller ends against the rib.", "Do not confuse T (125 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "ISO 355 makes the 400×600 mm envelope interchangeable but not the ratings: NTN prints 2790/4250 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Do not confuse T (125 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 2790/4250 kN ratings and 320 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32080UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32080UTG?", "a": "32080UTG is a metric 4T tapered roller bearing to ISO 355: 400 mm bore, 600 mm outside diameter and 125 mm assembled width T (15.748 × 23.622 × 4.921 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2790 kN, C0 4250 kN, Pu 320 kN, grease limiting speed 490 r/min, oil speed 700 r/min, mass about 110000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32080UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32080UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32080UTG designation encode the 400 mm bore?", "a": "last two digits 80 are the ISO bore code, ×5 = 400 mm (codes 00–03 use the 10/12/15/17 exception table). The 600 mm OD and 125 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32080UTG list two speeds, 490 and 700 r/min?", "a": "The lower figure, 490 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32080UTG at 700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32080UTG mean?", "a": "Suffix reading on 32080UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32080UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32080utg", "＊32080utg", "32080UTG" ], "locale_variants": {} }, { "sku": "32984UTG", "brand": "NTN", "manufacturer_designation": "NTN 32984UTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 420, "D_mm": 560, "B_mm": 87, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 1570, "static_load_kN": 2840, "fatigue_load_limit_kN": 215, "limiting_speed_rpm": 490, "max_rpm": 490, "speed_oil_rpm": 700, "weight_g": 56200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32984UTG is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 420×560 mm ISO 355 envelope, with 87 mm overall assembled width T. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32984UTG by the metric ISO 355 number: 420 mm bore, 560 mm OD. Individually mounted, 32984UTG takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. The fatigue load limit Pu printed for 32984UTG is 215 kN; in the adjusted-life equation that is the equivalent-load floor below which high reliability is expected even under contamination. Mount the 420 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32984UTG.", "applications": [ "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains", "rolling-mill roll-neck and gearbox positions" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammering during fitting" ], "pitfalls": [ "At 420 mm bore the 32984UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 1570 kN C level.", "The thin 87 mm section of 32984UTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 420 mm bore smears the roller ends against the rib.", "Do not confuse T (87 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Open 32984UTG units have no seals: a wheel-hub or gearbox application needs external sealing or the 490 r/min grease figure is meaningless once water reaches the cone rib.", "Never fit the 420 mm cone by hammering the 560 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 1570/2840 kN ratings and 215 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32984UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32984UTG?", "a": "32984UTG is a metric 4T tapered roller bearing to ISO 355: 420 mm bore, 560 mm outside diameter and 87 mm assembled width T (16.535 × 22.047 × 3.425 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1570 kN, C0 2840 kN, Pu 215 kN, grease limiting speed 490 r/min, oil speed 700 r/min, mass about 56200 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32984UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32984UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32984UTG designation encode the 420 mm bore?", "a": "last two digits 84 are the ISO bore code, ×5 = 420 mm (codes 00–03 use the 10/12/15/17 exception table). The 560 mm OD and 87 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32984UTG list two speeds, 490 and 700 r/min?", "a": "The lower figure, 490 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32984UTG at 700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32984UTG mean?", "a": "Suffix reading on 32984UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32984UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32984utg", "＊32984utg", "32984UTG" ], "locale_variants": {} }, { "sku": "32084UTG", "brand": "NTN", "manufacturer_designation": "NTN 32084UTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 420, "D_mm": 620, "B_mm": 125, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2920, "static_load_kN": 4550, "fatigue_load_limit_kN": 340, "limiting_speed_rpm": 460, "max_rpm": 460, "speed_oil_rpm": 660, "weight_g": 120000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32084UTG belongs to the NTN metric 4T tapered roller range (low-section 32000 family tuned for low friction); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. The last two digits 84 are the ISO bore code, ×5 = 420 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 125 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32084UTG cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. Selection: C 2920 kN against C0 4550 kN gives a C0/C ratio of 1.56 for the 420 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 420 mm pair is misadjusted and the 125 mm T set will edge-load in service.", "applications": [ "rolling-mill roll-neck and gearbox positions", "large crusher and SAG/AG-mill drive shafts", "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 420 mm bore the 32084UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2920 kN C level.", "The thin 125 mm section of 32084UTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 420 mm bore smears the roller ends against the rib.", "Grease packs must leave free volume in the 125 mm-wide set; over-greasing a paired bearing churning at the 660 r/min oil-band speed raises temperature and destroys the preload setting.", "Do not confuse T (125 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "Do not confuse T (125 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.", "The 2920/4550 kN ratings and 340 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32084UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32084UTG?", "a": "32084UTG is a metric 4T tapered roller bearing to ISO 355: 420 mm bore, 620 mm outside diameter and 125 mm assembled width T (16.535 × 24.409 × 4.921 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2920 kN, C0 4550 kN, Pu 340 kN, grease limiting speed 460 r/min, oil speed 660 r/min, mass about 120000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32084UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32084UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32084UTG designation encode the 420 mm bore?", "a": "last two digits 84 are the ISO bore code, ×5 = 420 mm (codes 00–03 use the 10/12/15/17 exception table). The 620 mm OD and 125 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32084UTG list two speeds, 460 and 660 r/min?", "a": "The lower figure, 460 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32084UTG at 660 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32084UTG mean?", "a": "Suffix reading on 32084UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32084UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32084utg", "＊32084utg", "32084UTG" ], "locale_variants": {} }, { "sku": "32988UTG", "brand": "NTN", "manufacturer_designation": "NTN 32988UTG", "series": "32900-series", "type": "tapered_roller", "d_mm": 440, "D_mm": 600, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 2060, "static_load_kN": 3450, "fatigue_load_limit_kN": 258, "limiting_speed_rpm": 470, "max_rpm": 470, "speed_oil_rpm": 670, "weight_g": 76000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "32988UTG belongs to the NTN metric 4T tapered roller range (extra-light thin-section 32900 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. NTN also quotes this bearing with its ISO 355 dimension-series abbreviation which is the maker-neutral cross-reference for the 440×600 mm envelope; 4T is NTN's own tapered-roller brand mark on the parts. Individually mounted, 32988UTG takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Catalogue mass of the 32988UTG set is 76000 g (2.992 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. Open 4T bearings need application seals; without them the grease at the cone rib of 32988UTG washes out and the rib/roller-end contact smears on the first wet or dusty shift.", "applications": [ "wind-turbine gearbox and main-shaft arrangements", "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears" ], "failure_modes": [ "cup creep and housing fretting when the specified outer-ring press fit is not achieved", "smearing on the roller large ends and cone rib after a dry start with preload but no oil film", "flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 440 mm bore the 32988UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 2060 kN C level.", "The thin 100 mm section of 32988UTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 440 mm bore smears the roller ends against the rib.", "Grease packs must leave free volume in the 100 mm-wide set; over-greasing a paired bearing churning at the 670 r/min oil-band speed raises temperature and destroys the preload setting.", "ISO 355 makes the 440×600 mm envelope interchangeable but not the ratings: NTN prints 2060/3450 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.", "Never fit the 440 mm cone by hammering the 600 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 2060/3450 kN ratings and 258 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32988UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32988UTG?", "a": "32988UTG is a metric 4T tapered roller bearing to ISO 355: 440 mm bore, 600 mm outside diameter and 100 mm assembled width T (17.323 × 23.622 × 3.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 2060 kN, C0 3450 kN, Pu 258 kN, grease limiting speed 470 r/min, oil speed 670 r/min, mass about 76000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32988UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32988UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32988UTG designation encode the 440 mm bore?", "a": "last two digits 88 are the ISO bore code, ×5 = 440 mm (codes 00–03 use the 10/12/15/17 exception table). The 600 mm OD and 100 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32988UTG list two speeds, 470 and 670 r/min?", "a": "The lower figure, 470 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32988UTG at 670 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32988UTG mean?", "a": "Suffix reading on 32988UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32988UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32988utg", "＊32988utg", "32988UTG" ], "locale_variants": {} }, { "sku": "32088UTG", "brand": "NTN", "manufacturer_designation": "NTN 32088UTG", "series": "32000-series", "type": "tapered_roller", "d_mm": 440, "D_mm": 650, "B_mm": 130, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 3250, "static_load_kN": 5000, "fatigue_load_limit_kN": 365, "limiting_speed_rpm": 440, "max_rpm": 440, "speed_oil_rpm": 620, "weight_g": 140000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 355", "naming_rule_text": "For a 440 mm shaft with a thrust component, NTN lists 32088UTG, a metric 4T tapered roller bearing of 3250 kN C and 5000 kN C0 inside the 650 mm OD, 130 mm-wide assembled set. The last two digits 88 are the ISO bore code, ×5 = 440 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 130 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. NTN adjusts these bearings by cup or cone position rather than shipping a preloaded set; the mounting drawing must state end play or preload for 32088UTG, since running clearance is set during assembly. Imperial cross-check for the drawing: 440×650×130 mm is 17.323 × 25.591 × 5.118 in; ISO 355 makes the envelope interchangeable but C/C0, 3250/5000 kN, is NTN-specific. Mount the 440 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32088UTG.", "applications": [ "offshore crane and drawworks drums", "heavy haul railway traction gearboxes", "large marine propulsion reduction gears", "cement-plant kiln and mill drive trains" ], "failure_modes": [ "cone-raceway spalling at the large rib when preload is set too high for the lubricant film", "preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play", "rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair", "cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in unsealed open arrangements" ], "pitfalls": [ "At 440 mm bore the 32088UTG set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 3250 kN C level.", "The thin 130 mm section of 32088UTG is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 440 mm bore smears the roller ends against the rib.", "Minimum load matters at high speed: an unloaded 32088UTG at a large fraction of 440 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.", "The 105.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32088UTG or the ring will bottom out on the radius instead of the shoulder face.", "On slash-size and T-code bearings confirm the full code on both cone and cup before fitting: the 440 mm bore alone does not identify the cup, and a mismatched cone/cup set has no catalogue rating.", "The 3250/5000 kN ratings and 365 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32088UTG; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 32088UTG?", "a": "32088UTG is a metric 4T tapered roller bearing to ISO 355: 440 mm bore, 650 mm outside diameter and 130 mm assembled width T (17.323 × 25.591 × 5.118 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 3250 kN, C0 5000 kN, Pu 365 kN, grease limiting speed 440 r/min, oil speed 620 r/min, mass about 140000 g. It is an open, separable cone/cup bearing with a pressed-steel cage." }, { "q": "What does the 4T prefix mean on 32088UTG?", "a": "4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32088UTG); the lower-case 4t- factory spelling of the code is retained among the search aliases." }, { "q": "How does the 32088UTG designation encode the 440 mm bore?", "a": "last two digits 88 are the ISO bore code, ×5 = 440 mm (codes 00–03 use the 10/12/15/17 exception table). The 650 mm OD and 130 mm assembled T follow the ISO 355 dimension-series plan." }, { "q": "Why does 32088UTG list two speeds, 440 and 620 r/min?", "a": "The lower figure, 440 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32088UTG at 620 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling." }, { "q": "What does the suffix on 32088UTG mean?", "a": "Suffix reading on 32088UTG: the UTG suffix marks the ULTAGE specification for large NTN tapered rollers — upgraded material and internal design for longer life inside the unchanged ISO 355 envelope; the suffix is part of the order number and the variants are not interchangeable articles." } ], "cross_ref": [ { "equiv_sku": "32088UTG", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/ntn_ball_roller_2203E.pdf#page=174", "catalog_ver": "NTN Ball and Roller Bearings CAT.No.2203E", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "32088utg", "＊32088utg", "32088UTG" ], "locale_variants": {} }, { "sku": "A4050-A4138", "brand": "NTN", "manufacturer_designation": "NTN 4T-A4050/A4138", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 12.7, "D_mm": 34.988, "B_mm": 10.998, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 13.7, "static_load_kN": 11.6, "limiting_speed_rpm": 12000, "max_rpm": 12000, "speed_oil_rpm": 16000, "weight_g": 53, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-A4050/A4138 denotes the A small-size family of NTN inch tapered roller bearings — cone A4050 and cup A4138 delivered as a matched, separable pair of 12.7 mm bore and 34.988 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — A4050 sits in the A small-size family. The 1.1 kN of dynamic capacity per millimetre of bore summarises the 13.7 kN rating over the 12.7 mm bore — sanity-check any interchange candidate against this ratio and the 10.998 mm T. Cup-side note for A4138: within the A small-size family tables the A4050 cone is listed against several cup options, and it is the cup that fixes the 34.988 mm OD and the 10.998 mm assembled width — quote the full A4050/A4138 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-A4050/A4138, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 12.7 mm (0.5 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-A4050/A4138 pair with a dial indicator on end play rather than by locknut feel.", "The A small-size family at 12.7 mm bore (34.988×10.998 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full A4050/A4138 reference at purchase.", "Never drive the 34.988 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Shaft and housing fillets must clear the ring chamfers of A4050 and A4138; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full A4050/A4138 pair at ordering: the A4050 cone also ships against sibling cups, and a cup from another reference changes the 10.998 mm assembled width and the rating.", "The 13.7/11.6 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-A4050/A4138; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-A4050/A4138?", "a": "4T-A4050/A4138 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 12.7 mm bore (0.5 in), 34.988 mm outside diameter and 10.998 mm assembled width T (1.377 × 0.433 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 13.7 kN, C0 11.6 kN, grease limiting speed 12,000 r/min, oil speed 16,000 r/min, mass about 53 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-A4050/A4138 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the A4050 cone or the A4138 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 13.7/11.6 kN ratings change with the cup." }, { "q": "What is the difference between 4T-A4050/A4138 and a metric ISO 355 tapered bearing?", "a": "4T-A4050/A4138 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 12.7×34.988×10.998 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-A4050/A4138 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare A4050/A4138 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-A4050/A4138 list two speeds, 12,000 and 16,000 r/min?", "a": "The lower figure, 12,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-A4050/A4138 at 16,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "A4050", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-a4050-a4138", "a4050-a4138", "A4050-A4138", "4T-A4050-A4138" ], "locale_variants": {} }, { "sku": "A4059-A4138-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-A4059/A4138", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 14.989, "D_mm": 34.988, "B_mm": 10.998, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 13.7, "static_load_kN": 11.6, "limiting_speed_rpm": 12000, "max_rpm": 12000, "speed_oil_rpm": 16000, "weight_g": 49, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-A4059/A4138 at 14.989 mm bore (0.59 in), 34.988 mm cup OD and 10.998 mm assembled T, with a grease limiting speed of 12,000 r/min and an oil ceiling of 16,000 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: A4059 identifies the cone of 14.989 mm (0.59 in) bore by catalogue lookup, and A4138 fixes the 34.988 mm OD. Speed planning uses both catalogue columns: grease 12,000 r/min is the mechanical ceiling for 4T-A4059/A4138, oil 16,000 r/min with circulating oil — a 4,000 r/min margin at this size. Housing fitment sequence for 4T-A4059/A4138: press the A4138 cup square into the 34.988 mm seat first, then bring the A4059 cone (on its 14.989 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-A4059/A4138 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 14.989 mm (0.59 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-A4059/A4138 pair with a dial indicator on end play rather than by locknut feel.", "The A small-size family at 14.989 mm bore (34.988×10.998 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full A4059/A4138 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of A4059 and A4138; use undercut shoulders so the rings seat on the face, not on a radius.", "Fit selection follows the rotating ring: a rotating cone on a 14.989 mm shaft takes a j5/k5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 10.998 mm-wide set; over-greasing a pair churning near the oil-band speed of 16,000 r/min raises temperature and destroys the setting.", "The 13.7/11.6 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-A4059/A4138; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-A4059/A4138?", "a": "4T-A4059/A4138 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 14.989 mm bore (0.59 in), 34.988 mm outside diameter and 10.998 mm assembled width T (1.377 × 0.433 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 13.7 kN, C0 11.6 kN, grease limiting speed 12,000 r/min, oil speed 16,000 r/min, mass about 49 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-A4059/A4138 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the A4059 cone or the A4138 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 13.7/11.6 kN ratings change with the cup." }, { "q": "What is the difference between 4T-A4059/A4138 and a metric ISO 355 tapered bearing?", "a": "4T-A4059/A4138 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 14.989×34.988×10.998 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-A4059/A4138 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare A4059/A4138 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-A4059/A4138 list two speeds, 12,000 and 16,000 r/min?", "a": "The lower figure, 12,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-A4059/A4138 at 16,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "A4059-A4138", "equiv_brand": "SKF", "level": "partial", "note": "Same 14.989×34.988×10.998 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-a4059-a4138", "a4059-a4138", "A4059-A4138", "4T-A4059-A4138", "A4059-A4138-NTN" ], "locale_variants": {} }, { "sku": "03062-03162", "brand": "NTN", "manufacturer_designation": "NTN 4T-03062/03162", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 15.875, "D_mm": 41.275, "B_mm": 14.288, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 22.6, "static_load_kN": 18.7, "limiting_speed_rpm": 10000, "max_rpm": 10000, "speed_oil_rpm": 13000, "weight_g": 93, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 15.875 mm carrying combined radial and thrust load, NTN lists 4T-03062/03162, a single-row 4T tapered roller set of 22.6 kN C and 18.7 kN C0 inside the 41.275 mm OD cup. Reading the designation: 4T-03062/03162 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Contact-angle geometry of the pure-numeric inch family gives 4T-03062/03162 its radial/axial load split — at 22.6/18.7 kN the static rating is about 0.83× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-03062/03162: press the 03162 cup square into the 41.275 mm seat first, then bring the 03062 cone (on its 15.875 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-03062/03162 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 15.875 mm (0.625 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-03062/03162 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 15.875 mm bore (41.275×14.288 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 03062/03162 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 14.288 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never drive the 41.275 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 15.875×41.275 mm envelope interchangeable, not the ratings: NTN prints 22.6/18.7 kN for this execution and another make of the same number can differ in roller complement.", "The 22.6/18.7 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-03062/03162; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-03062/03162?", "a": "4T-03062/03162 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 15.875 mm bore (0.625 in), 41.275 mm outside diameter and 14.288 mm assembled width T (1.625 × 0.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 22.6 kN, C0 18.7 kN, grease limiting speed 10,000 r/min, oil speed 13,000 r/min, mass about 93 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-03062/03162 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 03062 cone or the 03162 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 22.6/18.7 kN ratings change with the cup." }, { "q": "What is the difference between 4T-03062/03162 and a metric ISO 355 tapered bearing?", "a": "4T-03062/03162 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 15.875×41.275×14.288 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-03062/03162 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 03062/03162 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-03062/03162 list two speeds, 10,000 and 13,000 r/min?", "a": "The lower figure, 10,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-03062/03162 at 13,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "03062", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-03062-03162", "03062-03162", "4T-03062-03162" ], "locale_variants": {} }, { "sku": "11590-11520-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-11590/11520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 15.875, "D_mm": 42.862, "B_mm": 14.288, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 19.5, "static_load_kN": 17.5, "limiting_speed_rpm": 8700, "max_rpm": 8700, "speed_oil_rpm": 12000, "weight_g": 103, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-11590/11520 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 15.875×42.862×14.288 mm (assembled width T), for a shaft of about 15.875 mm (0.625 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 11590/11520 without it. The 13.5 mm radial section over the 15.875 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 19.5/17.5 kN ratings belong to the assembled 11590+11520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-11590/11520 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 15.875 mm (0.625 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-11590/11520 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 15.875 mm bore (42.862×14.288 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 11590/11520 reference at purchase.", "ABMA makes the 15.875×42.862 mm envelope interchangeable, not the ratings: NTN prints 19.5/17.5 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 11590/11520 pair at ordering: the 11590 cone also ships against sibling cups, and a cup from another reference changes the 14.288 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 15.875 mm shaft takes a j5/k5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 19.5/17.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-11590/11520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-11590/11520?", "a": "4T-11590/11520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 15.875 mm bore (0.625 in), 42.862 mm outside diameter and 14.288 mm assembled width T (1.687 × 0.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 19.5 kN, C0 17.5 kN, grease limiting speed 8,700 r/min, oil speed 12,000 r/min, mass about 103 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-11590/11520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 11590 cone or the 11520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 19.5/17.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-11590/11520 and a metric ISO 355 tapered bearing?", "a": "4T-11590/11520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 15.875×42.862×14.288 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-11590/11520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 11590/11520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-11590/11520 list two speeds, 8,700 and 12,000 r/min?", "a": "The lower figure, 8,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-11590/11520 at 12,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "11590-11520", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-11590-11520", "11590-11520", "4T-11590-11520", "11590-11520-NTN" ], "locale_variants": {} }, { "sku": "17580-17520", "brand": "NTN", "manufacturer_designation": "NTN 4T-17580/17520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 15.875, "D_mm": 42.862, "B_mm": 16.67, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 29.6, "static_load_kN": 26, "limiting_speed_rpm": 9800, "max_rpm": 9800, "speed_oil_rpm": 13000, "weight_g": 123, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 15.875 mm carrying combined radial and thrust load, NTN lists 4T-17580/17520, a single-row 4T tapered roller set of 29.6 kN C and 26 kN C0 inside the 42.862 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 17580 identifies the cone of 15.875 mm (0.625 in) bore by catalogue lookup, and 17520 fixes the 42.862 mm OD. The 13.5 mm radial section over the 15.875 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 29.6/26 kN ratings belong to the assembled 17580+17520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-17580/17520 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery", "utility-vehicle differential and pinion supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 15.875 mm (0.625 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-17580/17520 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 15.875 mm bore (42.862×16.67 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 17580/17520 reference at purchase.", "An unloaded 4T-17580/17520 near 9,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 16.67 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 16.67 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 29.6/26 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-17580/17520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-17580/17520?", "a": "4T-17580/17520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 15.875 mm bore (0.625 in), 42.862 mm outside diameter and 16.67 mm assembled width T (1.687 × 0.656 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 29.6 kN, C0 26 kN, grease limiting speed 9,800 r/min, oil speed 13,000 r/min, mass about 123 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-17580/17520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 17580 cone or the 17520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 29.6/26 kN ratings change with the cup." }, { "q": "What is the difference between 4T-17580/17520 and a metric ISO 355 tapered bearing?", "a": "4T-17580/17520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 15.875×42.862×16.67 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-17580/17520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 17580/17520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-17580/17520 list two speeds, 9,800 and 13,000 r/min?", "a": "The lower figure, 9,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-17580/17520 at 13,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "17580", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-17580-17520", "17580-17520", "4T-17580-17520" ], "locale_variants": {} }, { "sku": "05062-05185", "brand": "NTN", "manufacturer_designation": "NTN 4T-05062/05185", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 15.875, "D_mm": 47, "B_mm": 14.381, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 26.6, "static_load_kN": 24.2, "limiting_speed_rpm": 8600, "max_rpm": 8600, "speed_oil_rpm": 11000, "weight_g": 131, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-05062/05185 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 05062 and cup 05185 delivered as a matched, separable pair of 15.875 mm bore and 47 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 05062 sits in the pure-numeric inch family. The 15.6 mm radial section over the 15.875 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-05062/05185: press the 05185 cup square into the 47 mm seat first, then bring the 05062 cone (on its 15.875 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-05062/05185 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "conveyor roller and pulley shafts in inch-frame machinery", "utility-vehicle differential and pinion supports", "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 15.875 mm (0.625 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-05062/05185 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 15.875 mm bore (47×14.381 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 05062/05185 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 15.875 mm shaft takes a j5/k5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 15.875×47 mm envelope interchangeable, not the ratings: NTN prints 26.6/24.2 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-05062/05185 near 8,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 26.6/24.2 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-05062/05185; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-05062/05185?", "a": "4T-05062/05185 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 15.875 mm bore (0.625 in), 47 mm outside diameter and 14.381 mm assembled width T (1.85 × 0.566 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 26.6 kN, C0 24.2 kN, grease limiting speed 8,600 r/min, oil speed 11,000 r/min, mass about 131 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-05062/05185 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 05062 cone or the 05185 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 26.6/24.2 kN ratings change with the cup." }, { "q": "What is the difference between 4T-05062/05185 and a metric ISO 355 tapered bearing?", "a": "4T-05062/05185 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 15.875×47×14.381 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-05062/05185 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 05062/05185 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-05062/05185 list two speeds, 8,600 and 11,000 r/min?", "a": "The lower figure, 8,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-05062/05185 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "05062", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-05062-05185", "05062-05185", "4T-05062-05185" ], "locale_variants": {} }, { "sku": "09062-09195", "brand": "NTN", "manufacturer_designation": "NTN 4T-09062/09195", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 15.875, "D_mm": 49.225, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 42.5, "static_load_kN": 39, "limiting_speed_rpm": 8500, "max_rpm": 8500, "speed_oil_rpm": 11000, "weight_g": 203, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-09062/09195 at 15.875 mm bore (0.625 in), 49.225 mm cup OD and 19.845 mm assembled T, with a grease limiting speed of 8,500 r/min and an oil ceiling of 11,000 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 09062/09195 without it. Contact-angle geometry of the pure-numeric inch family gives 4T-09062/09195 its radial/axial load split — at 42.5/39 kN the static rating is about 0.92× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-09062/09195: press the 09195 cup square into the 49.225 mm seat first, then bring the 09062 cone (on its 15.875 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 15.875 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 15.875 mm (0.625 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-09062/09195 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 15.875 mm bore (49.225×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 09062/09195 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 15.875 mm shaft takes a j5/k5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of 09062 and 09195; use undercut shoulders so the rings seat on the face, not on a radius.", "Replacing one half of an adjusted pair without resetting end play negates the 19.845 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 42.5/39 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-09062/09195; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-09062/09195?", "a": "4T-09062/09195 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 15.875 mm bore (0.625 in), 49.225 mm outside diameter and 19.845 mm assembled width T (1.938 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 42.5 kN, C0 39 kN, grease limiting speed 8,500 r/min, oil speed 11,000 r/min, mass about 203 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-09062/09195 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 09062 cone or the 09195 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 42.5/39 kN ratings change with the cup." }, { "q": "What is the difference between 4T-09062/09195 and a metric ISO 355 tapered bearing?", "a": "4T-09062/09195 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 15.875×49.225×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-09062/09195 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 09062/09195 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-09062/09195 list two speeds, 8,500 and 11,000 r/min?", "a": "The lower figure, 8,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-09062/09195 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "09062", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-09062-09195", "09062-09195", "4T-09062-09195" ], "locale_variants": {} }, { "sku": "05066-05185", "brand": "NTN", "manufacturer_designation": "NTN 4T-05066/05185", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 16.993, "D_mm": 47, "B_mm": 14.381, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 26.6, "static_load_kN": 24.2, "limiting_speed_rpm": 8600, "max_rpm": 8600, "speed_oil_rpm": 11000, "weight_g": 130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-05066/05185 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 05066 and cup 05185 delivered as a matched, separable pair of 16.993 mm bore and 47 mm outside diameter. Cone and cup of 4T-05066/05185 are separately stocked parts: a worn 05185 cup can be replaced against the existing 05066 cone, provided the new cup carries the identical reference — pairing across references changes the 14.381 mm assembled width and the rating. Selection: C 26.6 kN against C0 24.2 kN gives a C0/C ratio of 0.91 for the 16.993 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 26.6/24.2 kN ratings belong to the assembled 05066+05185 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-05066/05185 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery", "utility-vehicle differential and pinion supports", "small machine-tool feed and spindle counter-supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 16.993 mm (0.669 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-05066/05185 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 16.993 mm bore (47×14.381 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 05066/05185 reference at purchase.", "Inch and metric bores collide on paper — 16.993 mm is 0.669 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 16.993 mm shaft takes a j5/k5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (14.381 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 26.6/24.2 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-05066/05185; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-05066/05185?", "a": "4T-05066/05185 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 16.993 mm bore (0.669 in), 47 mm outside diameter and 14.381 mm assembled width T (1.85 × 0.566 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 26.6 kN, C0 24.2 kN, grease limiting speed 8,600 r/min, oil speed 11,000 r/min, mass about 130 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-05066/05185 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 05066 cone or the 05185 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 26.6/24.2 kN ratings change with the cup." }, { "q": "What is the difference between 4T-05066/05185 and a metric ISO 355 tapered bearing?", "a": "4T-05066/05185 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 16.993×47×14.381 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-05066/05185 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 05066/05185 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-05066/05185 list two speeds, 8,600 and 11,000 r/min?", "a": "The lower figure, 8,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-05066/05185 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "05066", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-05066-05185", "05066-05185", "4T-05066-05185" ], "locale_variants": {} }, { "sku": "LM11749-LM11710", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM11749/LM11710", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 17.462, "D_mm": 39.878, "B_mm": 13.843, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 26.4, "static_load_kN": 24.2, "limiting_speed_rpm": 10000, "max_rpm": 10000, "speed_oil_rpm": 13000, "weight_g": 84, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-LM11749/LM11710 denotes the light-medium LM family of NTN inch tapered roller bearings — cone LM11749 and cup LM11710 delivered as a matched, separable pair of 17.462 mm bore and 39.878 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote LM11749/LM11710 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 13.843 mm T of each 4T-LM11749/LM11710 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for LM11710: within the light-medium LM family tables the LM11749 cone is listed against several cup options, and it is the cup that fixes the 39.878 mm OD and the 13.843 mm assembled width — quote the full LM11749/LM11710 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 17.462 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "utility-vehicle differential and pinion supports", "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 17.462 mm (0.687 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-LM11749/LM11710 pair with a dial indicator on end play rather than by locknut feel.", "The light-medium LM family at 17.462 mm bore (39.878×13.843 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM11749/LM11710 reference at purchase.", "Do not confuse T (13.843 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Never drive the 39.878 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Fit selection follows the rotating ring: a rotating cone on a 17.462 mm shaft takes a j5/k5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 26.4/24.2 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM11749/LM11710; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM11749/LM11710?", "a": "4T-LM11749/LM11710 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 17.462 mm bore (0.687 in), 39.878 mm outside diameter and 13.843 mm assembled width T (1.57 × 0.545 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 26.4 kN, C0 24.2 kN, grease limiting speed 10,000 r/min, oil speed 13,000 r/min, mass about 84 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM11749/LM11710 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM11749 cone or the LM11710 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 26.4/24.2 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM11749/LM11710 and a metric ISO 355 tapered bearing?", "a": "4T-LM11749/LM11710 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 17.462×39.878×13.843 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM11749/LM11710 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM11749/LM11710 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM11749/LM11710 list two speeds, 10,000 and 13,000 r/min?", "a": "The lower figure, 10,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM11749/LM11710 at 13,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM11749-710", "equiv_brand": "SKF", "level": "partial", "note": "Same 17.462×39.878×13.843 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm11749-lm11710", "lm11749-lm11710", "LM11749-LM11710", "4T-LM11749-LM11710" ], "locale_variants": {} }, { "sku": "A6075-A6157", "brand": "NTN", "manufacturer_designation": "NTN 4T-A6075/A6157", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 19.05, "D_mm": 39.992, "B_mm": 12.014, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 14.2, "static_load_kN": 12.8, "limiting_speed_rpm": 10000, "max_rpm": 10000, "speed_oil_rpm": 13000, "weight_g": 65, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-A6075/A6157 is the NTN 4T catalogue entry for a 19.05×39.992×12.014 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — A6075 sits in the A small-size family. Imperial cross-check for the drawing: 19.05×39.992×12.014 mm converts to 0.75 × 1.574 × 0.473 in; the ABMA envelope swaps with like-numbered inch parts but the 14.2/12.8 kN ratings are NTN-specific. The printed 14.2/12.8 kN ratings belong to the assembled A6075+A6157 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-A6075/A6157; reverse the fit logic when the cup rotates.", "applications": [ "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery", "utility-vehicle differential and pinion supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 19.05 mm (0.75 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-A6075/A6157 pair with a dial indicator on end play rather than by locknut feel.", "The A small-size family at 19.05 mm bore (39.992×12.014 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full A6075/A6157 reference at purchase.", "An unloaded 4T-A6075/A6157 near 10,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Open 4T-A6075/A6157 sets have no seals: a hub or gearbox needs external sealing or the 10,000 r/min grease figure is meaningless once water reaches the cone rib.", "Quote the full A6075/A6157 pair at ordering: the A6075 cone also ships against sibling cups, and a cup from another reference changes the 12.014 mm assembled width and the rating.", "The 14.2/12.8 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-A6075/A6157; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-A6075/A6157?", "a": "4T-A6075/A6157 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 19.05 mm bore (0.75 in), 39.992 mm outside diameter and 12.014 mm assembled width T (1.574 × 0.473 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 14.2 kN, C0 12.8 kN, grease limiting speed 10,000 r/min, oil speed 13,000 r/min, mass about 65 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-A6075/A6157 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the A6075 cone or the A6157 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 14.2/12.8 kN ratings change with the cup." }, { "q": "What is the difference between 4T-A6075/A6157 and a metric ISO 355 tapered bearing?", "a": "4T-A6075/A6157 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 19.05×39.992×12.014 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-A6075/A6157 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare A6075/A6157 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-A6075/A6157 list two speeds, 10,000 and 13,000 r/min?", "a": "The lower figure, 10,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-A6075/A6157 at 13,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "A6075", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-a6075-a6157", "a6075-a6157", "A6075-A6157", "4T-A6075-A6157" ], "locale_variants": {} }, { "sku": "LM11949-LM11910", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM11949/LM11910", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 19.05, "D_mm": 45.237, "B_mm": 15.494, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 31.5, "static_load_kN": 28.6, "limiting_speed_rpm": 8900, "max_rpm": 8900, "speed_oil_rpm": 12000, "weight_g": 123, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-LM11949/LM11910 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 19.05×45.237×15.494 mm (assembled width T), for a shaft of about 19.05 mm (0.75 in). Cone and cup of 4T-LM11949/LM11910 are separately stocked parts: a worn LM11910 cup can be replaced against the existing LM11949 cone, provided the new cup carries the identical reference — pairing across references changes the 15.494 mm assembled width and the rating. Contact-angle geometry of the light-medium LM family gives 4T-LM11949/LM11910 its radial/axial load split — at 31.5/28.6 kN the static rating is about 0.91× C, typical of inch tapered sets proportioned for combined duty. The printed 31.5/28.6 kN ratings belong to the assembled LM11949+LM11910 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 19.05 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "utility-vehicle differential and pinion supports", "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 19.05 mm (0.75 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-LM11949/LM11910 pair with a dial indicator on end play rather than by locknut feel.", "The light-medium LM family at 19.05 mm bore (45.237×15.494 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM11949/LM11910 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 15.494 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-LM11949/LM11910 sets have no seals: a hub or gearbox needs external sealing or the 8,900 r/min grease figure is meaningless once water reaches the cone rib.", "Never drive the 45.237 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 31.5/28.6 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM11949/LM11910; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM11949/LM11910?", "a": "4T-LM11949/LM11910 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 19.05 mm bore (0.75 in), 45.237 mm outside diameter and 15.494 mm assembled width T (1.781 × 0.61 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 31.5 kN, C0 28.6 kN, grease limiting speed 8,900 r/min, oil speed 12,000 r/min, mass about 123 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM11949/LM11910 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM11949 cone or the LM11910 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 31.5/28.6 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM11949/LM11910 and a metric ISO 355 tapered bearing?", "a": "4T-LM11949/LM11910 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 19.05×45.237×15.494 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM11949/LM11910 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM11949/LM11910 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM11949/LM11910 list two speeds, 8,900 and 12,000 r/min?", "a": "The lower figure, 8,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM11949/LM11910 at 12,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM11949-910", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm11949-lm11910", "lm11949-lm11910", "LM11949-LM11910", "4T-LM11949-LM11910" ], "locale_variants": {} }, { "sku": "05075-05185", "brand": "NTN", "manufacturer_designation": "NTN 4T-05075/05185", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 19.05, "D_mm": 47, "B_mm": 14.381, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 26.6, "static_load_kN": 24.2, "limiting_speed_rpm": 8600, "max_rpm": 8600, "speed_oil_rpm": 11000, "weight_g": 121, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-05075/05185 at 19.05 mm bore (0.75 in), 47 mm cup OD and 14.381 mm assembled T, with a grease limiting speed of 8,600 r/min and an oil ceiling of 11,000 r/min. Reading the designation: 4T-05075/05185 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 8,600 r/min limiting speed targets the cone-rib contact; sustaining 11,000 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-05075/05185: press the 05185 cup square into the 47 mm seat first, then bring the 05075 cone (on its 19.05 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-05075/05185; reverse the fit logic when the cup rotates.", "applications": [ "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery", "utility-vehicle differential and pinion supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 19.05 mm (0.75 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-05075/05185 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 19.05 mm bore (47×14.381 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 05075/05185 reference at purchase.", "An unloaded 4T-05075/05185 near 8,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of 05075 and 05185; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-05075/05185 near 8,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 26.6/24.2 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-05075/05185; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-05075/05185?", "a": "4T-05075/05185 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 19.05 mm bore (0.75 in), 47 mm outside diameter and 14.381 mm assembled width T (1.85 × 0.566 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 26.6 kN, C0 24.2 kN, grease limiting speed 8,600 r/min, oil speed 11,000 r/min, mass about 121 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-05075/05185 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 05075 cone or the 05185 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 26.6/24.2 kN ratings change with the cup." }, { "q": "What is the difference between 4T-05075/05185 and a metric ISO 355 tapered bearing?", "a": "4T-05075/05185 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 19.05×47×14.381 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-05075/05185 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 05075/05185 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-05075/05185 list two speeds, 8,600 and 11,000 r/min?", "a": "The lower figure, 8,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-05075/05185 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "05075", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-05075-05185", "05075-05185", "4T-05075-05185" ], "locale_variants": {} }, { "sku": "09067-09195", "brand": "NTN", "manufacturer_designation": "NTN 4T-09067/09195", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 19.05, "D_mm": 49.225, "B_mm": 18.034, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 42.5, "static_load_kN": 39, "limiting_speed_rpm": 8500, "max_rpm": 8500, "speed_oil_rpm": 11000, "weight_g": 179, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 19.05 mm carrying combined radial and thrust load, NTN lists 4T-09067/09195, a single-row 4T tapered roller set of 42.5 kN C and 39 kN C0 inside the 49.225 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 09067 sits in the pure-numeric inch family. Selection: C 42.5 kN against C0 39 kN gives a C0/C ratio of 0.92 for the 19.05 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-09067/09195: press the 09195 cup square into the 49.225 mm seat first, then bring the 09067 cone (on its 19.05 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-09067/09195 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 19.05 mm (0.75 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-09067/09195 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 19.05 mm bore (49.225×18.034 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 09067/09195 reference at purchase.", "Inch and metric bores collide on paper — 19.05 mm is 0.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Do not confuse T (18.034 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Quote the full 09067/09195 pair at ordering: the 09067 cone also ships against sibling cups, and a cup from another reference changes the 18.034 mm assembled width and the rating.", "The 42.5/39 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-09067/09195; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-09067/09195?", "a": "4T-09067/09195 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 19.05 mm bore (0.75 in), 49.225 mm outside diameter and 18.034 mm assembled width T (1.938 × 0.71 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 42.5 kN, C0 39 kN, grease limiting speed 8,500 r/min, oil speed 11,000 r/min, mass about 179 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-09067/09195 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 09067 cone or the 09195 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 42.5/39 kN ratings change with the cup." }, { "q": "What is the difference between 4T-09067/09195 and a metric ISO 355 tapered bearing?", "a": "4T-09067/09195 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 19.05×49.225×18.034 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-09067/09195 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 09067/09195 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-09067/09195 list two speeds, 8,500 and 11,000 r/min?", "a": "The lower figure, 8,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-09067/09195 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "09067-09196", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-09067 paired with a different cup (09196): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-09067-09195", "09067-09195", "4T-09067-09195" ], "locale_variants": {} }, { "sku": "09067-09196", "brand": "NTN", "manufacturer_designation": "NTN 4T-09067/09196", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 19.05, "D_mm": 49.225, "B_mm": 21.209, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 42.5, "static_load_kN": 39, "limiting_speed_rpm": 8500, "max_rpm": 8500, "speed_oil_rpm": 11000, "weight_g": 198, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-09067/09196 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-09067/09196 are separately stocked parts: a worn 09196 cup can be replaced against the existing 09067 cone, provided the new cup carries the identical reference — pairing across references changes the 21.209 mm assembled width and the rating. Contact-angle geometry of the pure-numeric inch family gives 4T-09067/09196 its radial/axial load split — at 42.5/39 kN the static rating is about 0.92× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-09067/09196: press the 09196 cup square into the 49.225 mm seat first, then bring the 09067 cone (on its 19.05 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-09067/09196 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery", "utility-vehicle differential and pinion supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 19.05 mm (0.75 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-09067/09196 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 19.05 mm bore (49.225×21.209 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 09067/09196 reference at purchase.", "Open 4T-09067/09196 sets have no seals: a hub or gearbox needs external sealing or the 8,500 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 19.05×49.225 mm envelope interchangeable, not the ratings: NTN prints 42.5/39 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-09067/09196 near 8,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 42.5/39 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-09067/09196; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-09067/09196?", "a": "4T-09067/09196 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 19.05 mm bore (0.75 in), 49.225 mm outside diameter and 21.209 mm assembled width T (1.938 × 0.835 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 42.5 kN, C0 39 kN, grease limiting speed 8,500 r/min, oil speed 11,000 r/min, mass about 198 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-09067/09196 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 09067 cone or the 09196 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 42.5/39 kN ratings change with the cup." }, { "q": "What is the difference between 4T-09067/09196 and a metric ISO 355 tapered bearing?", "a": "4T-09067/09196 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 19.05×49.225×21.209 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-09067/09196 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 09067/09196 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-09067/09196 list two speeds, 8,500 and 11,000 r/min?", "a": "The lower figure, 8,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-09067/09196 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "09067-09195", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-09067 paired with a different cup (09195): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-09067-09196", "09067-09196", "4T-09067-09196" ], "locale_variants": {} }, { "sku": "09078-09195", "brand": "NTN", "manufacturer_designation": "NTN 4T-09078/09195", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 19.05, "D_mm": 49.225, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 42.5, "static_load_kN": 39, "limiting_speed_rpm": 8500, "max_rpm": 8500, "speed_oil_rpm": 11000, "weight_g": 190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-09078/09195 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-09078/09195 are separately stocked parts: a worn 09195 cup can be replaced against the existing 09078 cone, provided the new cup carries the identical reference — pairing across references changes the 19.845 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 19.845 mm T of each 4T-09078/09195 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 42.5/39 kN ratings belong to the assembled 09078+09195 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-09078/09195 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 19.05 mm (0.75 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-09078/09195 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 19.05 mm bore (49.225×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 09078/09195 reference at purchase.", "Grease packs must leave free volume inside the 19.845 mm-wide set; over-greasing a pair churning near the oil-band speed of 11,000 r/min raises temperature and destroys the setting.", "ABMA makes the 19.05×49.225 mm envelope interchangeable, not the ratings: NTN prints 42.5/39 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 09078/09195 pair at ordering: the 09078 cone also ships against sibling cups, and a cup from another reference changes the 19.845 mm assembled width and the rating.", "The 42.5/39 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-09078/09195; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-09078/09195?", "a": "4T-09078/09195 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 19.05 mm bore (0.75 in), 49.225 mm outside diameter and 19.845 mm assembled width T (1.938 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 42.5 kN, C0 39 kN, grease limiting speed 8,500 r/min, oil speed 11,000 r/min, mass about 190 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-09078/09195 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 09078 cone or the 09195 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 42.5/39 kN ratings change with the cup." }, { "q": "What is the difference between 4T-09078/09195 and a metric ISO 355 tapered bearing?", "a": "4T-09078/09195 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 19.05×49.225×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-09078/09195 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 09078/09195 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-09078/09195 list two speeds, 8,500 and 11,000 r/min?", "a": "The lower figure, 8,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-09078/09195 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "09078", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-09078-09195", "09078-09195", "4T-09078-09195" ], "locale_variants": {} }, { "sku": "21075-21212", "brand": "NTN", "manufacturer_designation": "NTN 4T-21075/21212", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 19.05, "D_mm": 53.975, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 44.5, "static_load_kN": 39, "limiting_speed_rpm": 8000, "max_rpm": 8000, "speed_oil_rpm": 11000, "weight_g": 248, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 19.05 mm carrying combined radial and thrust load, NTN lists 4T-21075/21212, a single-row 4T tapered roller set of 44.5 kN C and 39 kN C0 inside the 53.975 mm OD cup. Cone and cup of 4T-21075/21212 are separately stocked parts: a worn 21212 cup can be replaced against the existing 21075 cone, provided the new cup carries the identical reference — pairing across references changes the 22.225 mm assembled width and the rating. Grease relubrication at the 8,000 r/min limiting speed targets the cone-rib contact; sustaining 11,000 r/min needs an oil supply directed at the large roller ends. The printed 44.5/39 kN ratings belong to the assembled 21075+21212 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-21075/21212 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 19.05 mm (0.75 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-21075/21212 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 19.05 mm bore (53.975×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 21075/21212 reference at purchase.", "Do not confuse T (22.225 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Inch and metric bores collide on paper — 19.05 mm is 0.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 19.05 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 44.5/39 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-21075/21212; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-21075/21212?", "a": "4T-21075/21212 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 19.05 mm bore (0.75 in), 53.975 mm outside diameter and 22.225 mm assembled width T (2.125 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 44.5 kN, C0 39 kN, grease limiting speed 8,000 r/min, oil speed 11,000 r/min, mass about 248 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-21075/21212 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 21075 cone or the 21212 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 44.5/39 kN ratings change with the cup." }, { "q": "What is the difference between 4T-21075/21212 and a metric ISO 355 tapered bearing?", "a": "4T-21075/21212 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 19.05×53.975×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-21075/21212 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 21075/21212 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-21075/21212 list two speeds, 8,000 and 11,000 r/min?", "a": "The lower figure, 8,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-21075/21212 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "21075", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-21075-21212", "21075-21212", "4T-21075-21212" ], "locale_variants": {} }, { "sku": "1775-1729", "brand": "NTN", "manufacturer_designation": "NTN 4T-1775/1729", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 19.05, "D_mm": 56.896, "B_mm": 19.368, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 47.5, "static_load_kN": 46.5, "limiting_speed_rpm": 7200, "max_rpm": 7200, "speed_oil_rpm": 9600, "weight_g": 268, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-1775/1729 at 19.05 mm bore (0.75 in), 56.896 mm cup OD and 19.368 mm assembled T, with a grease limiting speed of 7,200 r/min and an oil ceiling of 9,600 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 1775 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 7,200 r/min is the mechanical ceiling for 4T-1775/1729, oil 9,600 r/min with circulating oil — a 2,400 r/min margin at this size. Housing fitment sequence for 4T-1775/1729: press the 1729 cup square into the 56.896 mm seat first, then bring the 1775 cone (on its 19.05 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-1775/1729 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 19.05 mm (0.75 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-1775/1729 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 19.05 mm bore (56.896×19.368 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 1775/1729 reference at purchase.", "Open 4T-1775/1729 sets have no seals: a hub or gearbox needs external sealing or the 7,200 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 19.05×56.896 mm envelope interchangeable, not the ratings: NTN prints 47.5/46.5 kN for this execution and another make of the same number can differ in roller complement.", "Do not confuse T (19.368 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 47.5/46.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-1775/1729; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-1775/1729?", "a": "4T-1775/1729 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 19.05 mm bore (0.75 in), 56.896 mm outside diameter and 19.368 mm assembled width T (2.24 × 0.763 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 47.5 kN, C0 46.5 kN, grease limiting speed 7,200 r/min, oil speed 9,600 r/min, mass about 268 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-1775/1729 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 1775 cone or the 1729 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 47.5/46.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-1775/1729 and a metric ISO 355 tapered bearing?", "a": "4T-1775/1729 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 19.05×56.896×19.368 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-1775/1729 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 1775/1729 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-1775/1729 list two speeds, 7,200 and 9,600 r/min?", "a": "The lower figure, 7,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-1775/1729 at 9,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "1775", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-1775-1729", "1775-1729", "4T-1775-1729" ], "locale_variants": {} }, { "sku": "05079-05185", "brand": "NTN", "manufacturer_designation": "NTN 4T-05079/05185", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 19.987, "D_mm": 47, "B_mm": 14.381, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 26.6, "static_load_kN": 24.2, "limiting_speed_rpm": 8600, "max_rpm": 8600, "speed_oil_rpm": 11000, "weight_g": 118, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-05079/05185 at 19.987 mm bore (0.787 in), 47 mm cup OD and 14.381 mm assembled T, with a grease limiting speed of 8,600 r/min and an oil ceiling of 11,000 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 05079 identifies the cone of 19.987 mm (0.787 in) bore by catalogue lookup, and 05185 fixes the 47 mm OD. Grease relubrication at the 8,600 r/min limiting speed targets the cone-rib contact; sustaining 11,000 r/min needs an oil supply directed at the large roller ends. The printed 26.6/24.2 kN ratings belong to the assembled 05079+05185 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-05079/05185, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery", "utility-vehicle differential and pinion supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 19.987 mm (0.787 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-05079/05185 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 19.987 mm bore (47×14.381 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 05079/05185 reference at purchase.", "Open 4T-05079/05185 sets have no seals: a hub or gearbox needs external sealing or the 8,600 r/min grease figure is meaningless once water reaches the cone rib.", "Open 4T-05079/05185 sets have no seals: a hub or gearbox needs external sealing or the 8,600 r/min grease figure is meaningless once water reaches the cone rib.", "Do not confuse T (14.381 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 26.6/24.2 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-05079/05185; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-05079/05185?", "a": "4T-05079/05185 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 19.987 mm bore (0.787 in), 47 mm outside diameter and 14.381 mm assembled width T (1.85 × 0.566 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 26.6 kN, C0 24.2 kN, grease limiting speed 8,600 r/min, oil speed 11,000 r/min, mass about 118 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-05079/05185 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 05079 cone or the 05185 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 26.6/24.2 kN ratings change with the cup." }, { "q": "What is the difference between 4T-05079/05185 and a metric ISO 355 tapered bearing?", "a": "4T-05079/05185 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 19.987×47×14.381 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-05079/05185 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 05079/05185 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-05079/05185 list two speeds, 8,600 and 11,000 r/min?", "a": "The lower figure, 8,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-05079/05185 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "05079", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-05079-05185", "05079-05185", "4T-05079-05185" ], "locale_variants": {} }, { "sku": "07079-07196", "brand": "NTN", "manufacturer_designation": "NTN 4T-07079/07196", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 20, "D_mm": 50.005, "B_mm": 13.495, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 28.8, "static_load_kN": 27.9, "limiting_speed_rpm": 7500, "max_rpm": 7500, "speed_oil_rpm": 10000, "weight_g": 138, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 0.787 in (20 mm) shaft position as 4T-07079/07196: cone 07079, cup 07196, profiled rollers and a pressed-steel cage, rated 28.8 kN basic dynamic and 27.9 kN static. Reading the designation: 4T-07079/07196 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 15.0 mm radial section over the 20 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 28.8/27.9 kN ratings belong to the assembled 07079+07196 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-07079/07196 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 20 mm (0.787 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-07079/07196 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 20 mm bore (50.005×13.495 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 07079/07196 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 13.495 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ABMA makes the 20×50.005 mm envelope interchangeable, not the ratings: NTN prints 28.8/27.9 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 07079/07196 pair at ordering: the 07079 cone also ships against sibling cups, and a cup from another reference changes the 13.495 mm assembled width and the rating.", "The 28.8/27.9 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-07079/07196; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-07079/07196?", "a": "4T-07079/07196 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 20 mm bore (0.787 in), 50.005 mm outside diameter and 13.495 mm assembled width T (1.969 × 0.531 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 28.8 kN, C0 27.9 kN, grease limiting speed 7,500 r/min, oil speed 10,000 r/min, mass about 138 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-07079/07196 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 07079 cone or the 07196 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 28.8/27.9 kN ratings change with the cup." }, { "q": "What is the difference between 4T-07079/07196 and a metric ISO 355 tapered bearing?", "a": "4T-07079/07196 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 20×50.005×13.495 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-07079/07196 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 07079/07196 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-07079/07196 list two speeds, 7,500 and 10,000 r/min?", "a": "The lower figure, 7,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-07079/07196 at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "07079", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-07079-07196", "07079-07196", "4T-07079-07196" ], "locale_variants": {} }, { "sku": "09081-09195", "brand": "NTN", "manufacturer_designation": "NTN 4T-09081/09195", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 20.625, "D_mm": 49.225, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 42.5, "static_load_kN": 39, "limiting_speed_rpm": 8500, "max_rpm": 8500, "speed_oil_rpm": 11000, "weight_g": 180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-09081/09195 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 20.625×49.225×19.845 mm (assembled width T), for a shaft of about 20.625 mm (0.812 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 09081 sits in the pure-numeric inch family. The 14.3 mm radial section over the 20.625 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-09081/09195: press the 09195 cup square into the 49.225 mm seat first, then bring the 09081 cone (on its 20.625 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-09081/09195 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 20.625 mm (0.812 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-09081/09195 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 20.625 mm bore (49.225×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 09081/09195 reference at purchase.", "Quote the full 09081/09195 pair at ordering: the 09081 cone also ships against sibling cups, and a cup from another reference changes the 19.845 mm assembled width and the rating.", "An unloaded 4T-09081/09195 near 8,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 19.845 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 42.5/39 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-09081/09195; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-09081/09195?", "a": "4T-09081/09195 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 20.625 mm bore (0.812 in), 49.225 mm outside diameter and 19.845 mm assembled width T (1.938 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 42.5 kN, C0 39 kN, grease limiting speed 8,500 r/min, oil speed 11,000 r/min, mass about 180 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-09081/09195 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 09081 cone or the 09195 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 42.5/39 kN ratings change with the cup." }, { "q": "What is the difference between 4T-09081/09195 and a metric ISO 355 tapered bearing?", "a": "4T-09081/09195 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 20.625×49.225×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-09081/09195 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 09081/09195 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-09081/09195 list two speeds, 8,500 and 11,000 r/min?", "a": "The lower figure, 8,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-09081/09195 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "09081", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-09081-09195", "09081-09195", "4T-09081-09195" ], "locale_variants": {} }, { "sku": "12580-12520", "brand": "NTN", "manufacturer_designation": "NTN 4T-12580/12520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 20.638, "D_mm": 49.225, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 41.5, "static_load_kN": 39, "limiting_speed_rpm": 8200, "max_rpm": 8200, "speed_oil_rpm": 11000, "weight_g": 183, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-12580/12520 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 12580 and cup 12520 delivered as a matched, separable pair of 20.638 mm bore and 49.225 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 12580 identifies the cone of 20.638 mm (0.813 in) bore by catalogue lookup, and 12520 fixes the 49.225 mm OD. The 2.0 kN of dynamic capacity per millimetre of bore summarises the 41.5 kN rating over the 20.638 mm bore — sanity-check any interchange candidate against this ratio and the 19.845 mm T. Housing fitment sequence for 4T-12580/12520: press the 12520 cup square into the 49.225 mm seat first, then bring the 12580 cone (on its 20.638 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-12580/12520; reverse the fit logic when the cup rotates.", "applications": [ "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 20.638 mm (0.813 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-12580/12520 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 20.638 mm bore (49.225×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 12580/12520 reference at purchase.", "Grease packs must leave free volume inside the 19.845 mm-wide set; over-greasing a pair churning near the oil-band speed of 11,000 r/min raises temperature and destroys the setting.", "Replacing one half of an adjusted pair without resetting end play negates the 19.845 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Shaft and housing fillets must clear the ring chamfers of 12580 and 12520; use undercut shoulders so the rings seat on the face, not on a radius.", "The 41.5/39 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-12580/12520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-12580/12520?", "a": "4T-12580/12520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 20.638 mm bore (0.813 in), 49.225 mm outside diameter and 19.845 mm assembled width T (1.938 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 41.5 kN, C0 39 kN, grease limiting speed 8,200 r/min, oil speed 11,000 r/min, mass about 183 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-12580/12520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 12580 cone or the 12520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 41.5/39 kN ratings change with the cup." }, { "q": "What is the difference between 4T-12580/12520 and a metric ISO 355 tapered bearing?", "a": "4T-12580/12520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 20.638×49.225×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-12580/12520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 12580/12520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-12580/12520 list two speeds, 8,200 and 11,000 r/min?", "a": "The lower figure, 8,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-12580/12520 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "12580", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-12580-12520", "12580-12520", "4T-12580-12520" ], "locale_variants": {} }, { "sku": "M12649-M12610", "brand": "NTN", "manufacturer_designation": "NTN 4T-M12649/M12610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 21.43, "D_mm": 50.005, "B_mm": 17.526, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 42, "static_load_kN": 39, "limiting_speed_rpm": 8000, "max_rpm": 8000, "speed_oil_rpm": 11000, "weight_g": 169, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-M12649/M12610 belongs to the NTN inch 4T tapered roller range (medium M family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-M12649/M12610 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the medium M family lettering ties the pair to its boundary plan. Contact-angle geometry of the medium M family gives 4T-M12649/M12610 its radial/axial load split — at 42/39 kN the static rating is about 0.93× C, typical of inch tapered sets proportioned for combined duty. The printed 42/39 kN ratings belong to the assembled M12649+M12610 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 21.43 mm cone with an induction heater (max 120 °C) and press the 50.005 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 21.43 mm (0.844 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-M12649/M12610 pair with a dial indicator on end play rather than by locknut feel.", "The medium M family at 21.43 mm bore (50.005×17.526 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full M12649/M12610 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 17.526 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ABMA makes the 21.43×50.005 mm envelope interchangeable, not the ratings: NTN prints 42/39 kN for this execution and another make of the same number can differ in roller complement.", "Inch and metric bores collide on paper — 21.43 mm is 0.844 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 42/39 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-M12649/M12610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-M12649/M12610?", "a": "4T-M12649/M12610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 21.43 mm bore (0.844 in), 50.005 mm outside diameter and 17.526 mm assembled width T (1.969 × 0.69 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 42 kN, C0 39 kN, grease limiting speed 8,000 r/min, oil speed 11,000 r/min, mass about 169 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-M12649/M12610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the M12649 cone or the M12610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 42/39 kN ratings change with the cup." }, { "q": "What is the difference between 4T-M12649/M12610 and a metric ISO 355 tapered bearing?", "a": "4T-M12649/M12610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 21.43×50.005×17.526 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-M12649/M12610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare M12649/M12610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-M12649/M12610 list two speeds, 8,000 and 11,000 r/min?", "a": "The lower figure, 8,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-M12649/M12610 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "M12649-610", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-m12649-m12610", "m12649-m12610", "M12649-M12610", "4T-M12649-M12610" ], "locale_variants": {} }, { "sku": "LM12749-LM12711", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM12749/LM12711", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 21.986, "D_mm": 45.974, "B_mm": 15.494, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 33, "static_load_kN": 34, "limiting_speed_rpm": 8400, "max_rpm": 8400, "speed_oil_rpm": 11000, "weight_g": 123, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-LM12749/LM12711 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 21.986×45.974×15.494 mm (assembled width T), for a shaft of about 21.986 mm (0.866 in). Reading the designation: 4T-LM12749/LM12711 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the light-medium LM family lettering ties the pair to its boundary plan. The 12.0 mm radial section over the 21.986 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for LM12711: within the light-medium LM family tables the LM12749 cone is listed against several cup options, and it is the cup that fixes the 45.974 mm OD and the 15.494 mm assembled width — quote the full LM12749/LM12711 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 21.986 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 21.986 mm (0.866 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-LM12749/LM12711 pair with a dial indicator on end play rather than by locknut feel.", "The light-medium LM family at 21.986 mm bore (45.974×15.494 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM12749/LM12711 reference at purchase.", "Quote the full LM12749/LM12711 pair at ordering: the LM12749 cone also ships against sibling cups, and a cup from another reference changes the 15.494 mm assembled width and the rating.", "Grease packs must leave free volume inside the 15.494 mm-wide set; over-greasing a pair churning near the oil-band speed of 11,000 r/min raises temperature and destroys the setting.", "Replacing one half of an adjusted pair without resetting end play negates the 15.494 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 33/34 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM12749/LM12711; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM12749/LM12711?", "a": "4T-LM12749/LM12711 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 21.986 mm bore (0.866 in), 45.974 mm outside diameter and 15.494 mm assembled width T (1.81 × 0.61 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 33 kN, C0 34 kN, grease limiting speed 8,400 r/min, oil speed 11,000 r/min, mass about 123 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM12749/LM12711 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM12749 cone or the LM12711 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 33/34 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM12749/LM12711 and a metric ISO 355 tapered bearing?", "a": "4T-LM12749/LM12711 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 21.986×45.974×15.494 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM12749/LM12711 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM12749/LM12711 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM12749/LM12711 list two speeds, 8,400 and 11,000 r/min?", "a": "The lower figure, 8,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM12749/LM12711 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM12749-710", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "LM12749-711", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm12749-lm12711", "lm12749-lm12711", "LM12749-LM12711", "4T-LM12749-LM12711" ], "locale_variants": {} }, { "sku": "07087-07196", "brand": "NTN", "manufacturer_designation": "NTN 4T-07087/07196", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 22.225, "D_mm": 50.005, "B_mm": 13.495, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 28.8, "static_load_kN": 27.9, "limiting_speed_rpm": 7500, "max_rpm": 7500, "speed_oil_rpm": 10000, "weight_g": 128, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 0.875 in (22.225 mm) shaft position as 4T-07087/07196: cone 07087, cup 07196, profiled rollers and a pressed-steel cage, rated 28.8 kN basic dynamic and 27.9 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 07087/07196 without it. The 1.3 kN of dynamic capacity per millimetre of bore summarises the 28.8 kN rating over the 22.225 mm bore — sanity-check any interchange candidate against this ratio and the 13.495 mm T. Cup-side note for 07196: within the pure-numeric inch family tables the 07087 cone is listed against several cup options, and it is the cup that fixes the 50.005 mm OD and the 13.495 mm assembled width — quote the full 07087/07196 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 22.225 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "At 22.225 mm (0.875 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-07087/07196 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 22.225 mm bore (50.005×13.495 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 07087/07196 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 13.495 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never drive the 50.005 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "An unloaded 4T-07087/07196 near 7,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 28.8/27.9 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-07087/07196; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-07087/07196?", "a": "4T-07087/07196 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 22.225 mm bore (0.875 in), 50.005 mm outside diameter and 13.495 mm assembled width T (1.969 × 0.531 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 28.8 kN, C0 27.9 kN, grease limiting speed 7,500 r/min, oil speed 10,000 r/min, mass about 128 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-07087/07196 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 07087 cone or the 07196 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 28.8/27.9 kN ratings change with the cup." }, { "q": "What is the difference between 4T-07087/07196 and a metric ISO 355 tapered bearing?", "a": "4T-07087/07196 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 22.225×50.005×13.495 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-07087/07196 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 07087/07196 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-07087/07196 list two speeds, 7,500 and 10,000 r/min?", "a": "The lower figure, 7,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-07087/07196 at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "07087", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-07087-07196", "07087-07196", "4T-07087-07196" ], "locale_variants": {} }, { "sku": "M12648-M12610", "brand": "NTN", "manufacturer_designation": "NTN 4T-M12648/M12610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 22.225, "D_mm": 50.005, "B_mm": 17.526, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 42, "static_load_kN": 39, "limiting_speed_rpm": 8000, "max_rpm": 8000, "speed_oil_rpm": 11000, "weight_g": 165, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-M12648/M12610 at 22.225 mm bore (0.875 in), 50.005 mm cup OD and 17.526 mm assembled T, with a grease limiting speed of 8,000 r/min and an oil ceiling of 11,000 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — M12648 sits in the medium M family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 17.526 mm T of each 4T-M12648/M12610 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 42/39 kN ratings belong to the assembled M12648+M12610 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 22.225 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 22.225 mm (0.875 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-M12648/M12610 pair with a dial indicator on end play rather than by locknut feel.", "The medium M family at 22.225 mm bore (50.005×17.526 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full M12648/M12610 reference at purchase.", "Quote the full M12648/M12610 pair at ordering: the M12648 cone also ships against sibling cups, and a cup from another reference changes the 17.526 mm assembled width and the rating.", "ABMA makes the 22.225×50.005 mm envelope interchangeable, not the ratings: NTN prints 42/39 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 22.225×50.005 mm envelope interchangeable, not the ratings: NTN prints 42/39 kN for this execution and another make of the same number can differ in roller complement.", "The 42/39 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-M12648/M12610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-M12648/M12610?", "a": "4T-M12648/M12610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 22.225 mm bore (0.875 in), 50.005 mm outside diameter and 17.526 mm assembled width T (1.969 × 0.69 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 42 kN, C0 39 kN, grease limiting speed 8,000 r/min, oil speed 11,000 r/min, mass about 165 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-M12648/M12610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the M12648 cone or the M12610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 42/39 kN ratings change with the cup." }, { "q": "What is the difference between 4T-M12648/M12610 and a metric ISO 355 tapered bearing?", "a": "4T-M12648/M12610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 22.225×50.005×17.526 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-M12648/M12610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare M12648/M12610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-M12648/M12610 list two speeds, 8,000 and 11,000 r/min?", "a": "The lower figure, 8,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-M12648/M12610 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "M12648", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-m12648-m12610", "m12648-m12610", "M12648-M12610", "4T-M12648-M12610" ], "locale_variants": {} }, { "sku": "1380-1328-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-1380/1328", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 22.225, "D_mm": 52.388, "B_mm": 19.368, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 45, "static_load_kN": 43, "limiting_speed_rpm": 7600, "max_rpm": 7600, "speed_oil_rpm": 10000, "weight_g": 196, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-1380/1328 at 22.225 mm bore (0.875 in), 52.388 mm cup OD and 19.368 mm assembled T, with a grease limiting speed of 7,600 r/min and an oil ceiling of 10,000 r/min. Reading the designation: 4T-1380/1328 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 22.225×52.388×19.368 mm converts to 0.875 × 2.063 × 0.763 in; the ABMA envelope swaps with like-numbered inch parts but the 45/43 kN ratings are NTN-specific. Housing fitment sequence for 4T-1380/1328: press the 1328 cup square into the 52.388 mm seat first, then bring the 1380 cone (on its 22.225 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-1380/1328 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery", "utility-vehicle differential and pinion supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 22.225 mm (0.875 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-1380/1328 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 22.225 mm bore (52.388×19.368 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 1380/1328 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 19.368 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-1380/1328 sets have no seals: a hub or gearbox needs external sealing or the 7,600 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 22.225×52.388 mm envelope interchangeable, not the ratings: NTN prints 45/43 kN for this execution and another make of the same number can differ in roller complement.", "The 45/43 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-1380/1328; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-1380/1328?", "a": "4T-1380/1328 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 22.225 mm bore (0.875 in), 52.388 mm outside diameter and 19.368 mm assembled width T (2.063 × 0.763 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 45 kN, C0 43 kN, grease limiting speed 7,600 r/min, oil speed 10,000 r/min, mass about 196 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-1380/1328 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 1380 cone or the 1328 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 45/43 kN ratings change with the cup." }, { "q": "What is the difference between 4T-1380/1328 and a metric ISO 355 tapered bearing?", "a": "4T-1380/1328 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 22.225×52.388×19.368 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-1380/1328 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 1380/1328 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-1380/1328 list two speeds, 7,600 and 10,000 r/min?", "a": "The lower figure, 7,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-1380/1328 at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "1380-1328", "equiv_brand": "SKF", "level": "partial", "note": "Same 22.225×52.388×19.368 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "1380-1329", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-1380 paired with a different cup (1329): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-1380-1328", "1380-1328", "4T-1380-1328", "1380-1328-NTN" ], "locale_variants": {} }, { "sku": "1380-1329", "brand": "NTN", "manufacturer_designation": "NTN 4T-1380/1329", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 22.225, "D_mm": 53.975, "B_mm": 19.368, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 45, "static_load_kN": 43, "limiting_speed_rpm": 7600, "max_rpm": 7600, "speed_oil_rpm": 10000, "weight_g": 220, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 22.225 mm carrying combined radial and thrust load, NTN lists 4T-1380/1329, a single-row 4T tapered roller set of 45 kN C and 43 kN C0 inside the 53.975 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 1380 identifies the cone of 22.225 mm (0.875 in) bore by catalogue lookup, and 1329 fixes the 53.975 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 19.368 mm T of each 4T-1380/1329 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-1380/1329: press the 1329 cup square into the 53.975 mm seat first, then bring the 1380 cone (on its 22.225 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-1380/1329 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "utility-vehicle differential and pinion supports", "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 22.225 mm (0.875 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-1380/1329 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 22.225 mm bore (53.975×19.368 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 1380/1329 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 19.368 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 22.225 mm is 0.875 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-1380/1329 sets have no seals: a hub or gearbox needs external sealing or the 7,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 45/43 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-1380/1329; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-1380/1329?", "a": "4T-1380/1329 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 22.225 mm bore (0.875 in), 53.975 mm outside diameter and 19.368 mm assembled width T (2.125 × 0.763 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 45 kN, C0 43 kN, grease limiting speed 7,600 r/min, oil speed 10,000 r/min, mass about 220 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-1380/1329 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 1380 cone or the 1329 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 45/43 kN ratings change with the cup." }, { "q": "What is the difference between 4T-1380/1329 and a metric ISO 355 tapered bearing?", "a": "4T-1380/1329 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 22.225×53.975×19.368 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-1380/1329 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 1380/1329 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-1380/1329 list two speeds, 7,600 and 10,000 r/min?", "a": "The lower figure, 7,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-1380/1329 at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "1380-1328", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "1380-1328-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-1380 paired with a different cup (1328): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=175", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-1380-1329", "1380-1329", "4T-1380-1329" ], "locale_variants": {} }, { "sku": "1755-1729", "brand": "NTN", "manufacturer_designation": "NTN 4T-1755/1729", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 22.225, "D_mm": 56.896, "B_mm": 19.368, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 47.5, "static_load_kN": 46.5, "limiting_speed_rpm": 7200, "max_rpm": 7200, "speed_oil_rpm": 9600, "weight_g": 252, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-1755/1729 at 22.225 mm bore (0.875 in), 56.896 mm cup OD and 19.368 mm assembled T, with a grease limiting speed of 7,200 r/min and an oil ceiling of 9,600 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 1755 identifies the cone of 22.225 mm (0.875 in) bore by catalogue lookup, and 1729 fixes the 56.896 mm OD. Contact-angle geometry of the pure-numeric inch family gives 4T-1755/1729 its radial/axial load split — at 47.5/46.5 kN the static rating is about 0.98× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 1729: within the pure-numeric inch family tables the 1755 cone is listed against several cup options, and it is the cup that fixes the 56.896 mm OD and the 19.368 mm assembled width — quote the full 1755/1729 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-1755/1729; reverse the fit logic when the cup rotates.", "applications": [ "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "At 22.225 mm (0.875 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-1755/1729 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 22.225 mm bore (56.896×19.368 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 1755/1729 reference at purchase.", "Never drive the 56.896 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never drive the 56.896 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume inside the 19.368 mm-wide set; over-greasing a pair churning near the oil-band speed of 9,600 r/min raises temperature and destroys the setting.", "The 47.5/46.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-1755/1729; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-1755/1729?", "a": "4T-1755/1729 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 22.225 mm bore (0.875 in), 56.896 mm outside diameter and 19.368 mm assembled width T (2.24 × 0.763 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 47.5 kN, C0 46.5 kN, grease limiting speed 7,200 r/min, oil speed 9,600 r/min, mass about 252 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-1755/1729 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 1755 cone or the 1729 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 47.5/46.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-1755/1729 and a metric ISO 355 tapered bearing?", "a": "4T-1755/1729 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 22.225×56.896×19.368 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-1755/1729 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 1755/1729 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-1755/1729 list two speeds, 7,200 and 9,600 r/min?", "a": "The lower figure, 7,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-1755/1729 at 9,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "1755", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-1755-1729", "1755-1729", "4T-1755-1729" ], "locale_variants": {} }, { "sku": "1280-1220", "brand": "NTN", "manufacturer_designation": "NTN 4T-1280/1220", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 22.225, "D_mm": 57.15, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52.5, "static_load_kN": 49.5, "limiting_speed_rpm": 7100, "max_rpm": 7100, "speed_oil_rpm": 9500, "weight_g": 287, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-1280/1220 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 1280 identifies the cone of 22.225 mm (0.875 in) bore by catalogue lookup, and 1220 fixes the 57.15 mm OD. Contact-angle geometry of the pure-numeric inch family gives 4T-1280/1220 its radial/axial load split — at 52.5/49.5 kN the static rating is about 0.94× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-1280/1220: press the 1220 cup square into the 57.15 mm seat first, then bring the 1280 cone (on its 22.225 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-1280/1220 run near 7,100 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery", "utility-vehicle differential and pinion supports", "small machine-tool feed and spindle counter-supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 22.225 mm (0.875 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-1280/1220 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 22.225 mm bore (57.15×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 1280/1220 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 22.225 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Never drive the 57.15 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Quote the full 1280/1220 pair at ordering: the 1280 cone also ships against sibling cups, and a cup from another reference changes the 22.225 mm assembled width and the rating.", "The 52.5/49.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-1280/1220; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-1280/1220?", "a": "4T-1280/1220 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 22.225 mm bore (0.875 in), 57.15 mm outside diameter and 22.225 mm assembled width T (2.25 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52.5 kN, C0 49.5 kN, grease limiting speed 7,100 r/min, oil speed 9,500 r/min, mass about 287 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-1280/1220 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 1280 cone or the 1220 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52.5/49.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-1280/1220 and a metric ISO 355 tapered bearing?", "a": "4T-1280/1220 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 22.225×57.15×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-1280/1220 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 1280/1220 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-1280/1220 list two speeds, 7,100 and 9,500 r/min?", "a": "The lower figure, 7,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-1280/1220 at 9,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "1280", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-1280-1220", "1280-1220", "4T-1280-1220" ], "locale_variants": {} }, { "sku": "LM72849-LM72810", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM72849/LM72810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 22.606, "D_mm": 47, "B_mm": 15.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 30.5, "static_load_kN": 32.5, "limiting_speed_rpm": 8200, "max_rpm": 8200, "speed_oil_rpm": 11000, "weight_g": 125, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-LM72849/LM72810 is the NTN 4T catalogue entry for a 22.606×47×15.5 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Reading the designation: 4T-LM72849/LM72810 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the light-medium LM family lettering ties the pair to its boundary plan. The 12.2 mm radial section over the 22.606 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 30.5/32.5 kN ratings belong to the assembled LM72849+LM72810 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-LM72849/LM72810 run near 8,200 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts", "conveyor roller and pulley shafts in inch-frame machinery", "utility-vehicle differential and pinion supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 22.606 mm (0.89 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-LM72849/LM72810 pair with a dial indicator on end play rather than by locknut feel.", "The light-medium LM family at 22.606 mm bore (47×15.5 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM72849/LM72810 reference at purchase.", "Grease packs must leave free volume inside the 15.5 mm-wide set; over-greasing a pair churning near the oil-band speed of 11,000 r/min raises temperature and destroys the setting.", "Do not confuse T (15.5 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 15.5 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 30.5/32.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM72849/LM72810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM72849/LM72810?", "a": "4T-LM72849/LM72810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 22.606 mm bore (0.89 in), 47 mm outside diameter and 15.5 mm assembled width T (1.85 × 0.61 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 30.5 kN, C0 32.5 kN, grease limiting speed 8,200 r/min, oil speed 11,000 r/min, mass about 125 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM72849/LM72810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM72849 cone or the LM72810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 30.5/32.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM72849/LM72810 and a metric ISO 355 tapered bearing?", "a": "4T-LM72849/LM72810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 22.606×47×15.5 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM72849/LM72810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM72849/LM72810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM72849/LM72810 list two speeds, 8,200 and 11,000 r/min?", "a": "The lower figure, 8,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM72849/LM72810 at 11,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM72849", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm72849-lm72810", "lm72849-lm72810", "LM72849-LM72810", "4T-LM72849-LM72810" ], "locale_variants": {} }, { "sku": "07093-07196", "brand": "NTN", "manufacturer_designation": "NTN 4T-07093/07196", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 23.812, "D_mm": 50.005, "B_mm": 13.495, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 28.8, "static_load_kN": 27.9, "limiting_speed_rpm": 7500, "max_rpm": 7500, "speed_oil_rpm": 10000, "weight_g": 121, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-07093/07196 at 23.812 mm bore (0.937 in), 50.005 mm cup OD and 13.495 mm assembled T, with a grease limiting speed of 7,500 r/min and an oil ceiling of 10,000 r/min. Reading the designation: 4T-07093/07196 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 7,500 r/min limiting speed targets the cone-rib contact; sustaining 10,000 r/min needs an oil supply directed at the large roller ends. The printed 28.8/27.9 kN ratings belong to the assembled 07093+07196 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 23.812 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 23.812 mm (0.937 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-07093/07196 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 23.812 mm bore (50.005×13.495 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 07093/07196 reference at purchase.", "ABMA makes the 23.812×50.005 mm envelope interchangeable, not the ratings: NTN prints 28.8/27.9 kN for this execution and another make of the same number can differ in roller complement.", "Grease packs must leave free volume inside the 13.495 mm-wide set; over-greasing a pair churning near the oil-band speed of 10,000 r/min raises temperature and destroys the setting.", "Replacing one half of an adjusted pair without resetting end play negates the 13.495 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 28.8/27.9 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-07093/07196; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-07093/07196?", "a": "4T-07093/07196 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 23.812 mm bore (0.937 in), 50.005 mm outside diameter and 13.495 mm assembled width T (1.969 × 0.531 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 28.8 kN, C0 27.9 kN, grease limiting speed 7,500 r/min, oil speed 10,000 r/min, mass about 121 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-07093/07196 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 07093 cone or the 07196 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 28.8/27.9 kN ratings change with the cup." }, { "q": "What is the difference between 4T-07093/07196 and a metric ISO 355 tapered bearing?", "a": "4T-07093/07196 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 23.812×50.005×13.495 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-07093/07196 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 07093/07196 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-07093/07196 list two speeds, 7,500 and 10,000 r/min?", "a": "The lower figure, 7,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-07093/07196 at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "07093", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-07093-07196", "07093-07196", "4T-07093-07196" ], "locale_variants": {} }, { "sku": "L44640-L44610", "brand": "NTN", "manufacturer_designation": "NTN 4T-L44640/L44610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 23.812, "D_mm": 50.292, "B_mm": 14.224, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 32, "static_load_kN": 34, "limiting_speed_rpm": 7400, "max_rpm": 7400, "speed_oil_rpm": 9900, "weight_g": 133, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-L44640/L44610 at 23.812 mm bore (0.937 in), 50.292 mm cup OD and 14.224 mm assembled T, with a grease limiting speed of 7,400 r/min and an oil ceiling of 9,900 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: L44640 identifies the cone of 23.812 mm (0.937 in) bore by catalogue lookup, and L44610 fixes the 50.292 mm OD. Catalogue mass of the 4T-L44640/L44610 cone-plus-cup set is 133 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for L44610: within the light L family tables the L44640 cone is listed against several cup options, and it is the cup that fixes the 50.292 mm OD and the 14.224 mm assembled width — quote the full L44640/L44610 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-L44640/L44610 run near 7,400 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "At 23.812 mm (0.937 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-L44640/L44610 pair with a dial indicator on end play rather than by locknut feel.", "The light L family at 23.812 mm bore (50.292×14.224 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L44640/L44610 reference at purchase.", "ABMA makes the 23.812×50.292 mm envelope interchangeable, not the ratings: NTN prints 32/34 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-L44640/L44610 near 7,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (14.224 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 32/34 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L44640/L44610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L44640/L44610?", "a": "4T-L44640/L44610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 23.812 mm bore (0.937 in), 50.292 mm outside diameter and 14.224 mm assembled width T (1.98 × 0.56 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 32 kN, C0 34 kN, grease limiting speed 7,400 r/min, oil speed 9,900 r/min, mass about 133 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L44640/L44610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L44640 cone or the L44610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 32/34 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L44640/L44610 and a metric ISO 355 tapered bearing?", "a": "4T-L44640/L44610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 23.812×50.292×14.224 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L44640/L44610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L44640/L44610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L44640/L44610 list two speeds, 7,400 and 9,900 r/min?", "a": "The lower figure, 7,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L44640/L44610 at 9,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L44640", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l44640-l44610", "l44640-l44610", "L44640-L44610", "4T-L44640-L44610" ], "locale_variants": {} }, { "sku": "1779-1729", "brand": "NTN", "manufacturer_designation": "NTN 4T-1779/1729", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 23.812, "D_mm": 56.896, "B_mm": 19.368, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 47.5, "static_load_kN": 46.5, "limiting_speed_rpm": 7200, "max_rpm": 7200, "speed_oil_rpm": 9600, "weight_g": 244, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-1779/1729 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 23.812×56.896×19.368 mm (assembled width T), for a shaft of about 23.812 mm (0.937 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 1779 sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 19.368 mm T of each 4T-1779/1729 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-1779/1729: press the 1729 cup square into the 56.896 mm seat first, then bring the 1779 cone (on its 23.812 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-1779/1729, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "conveyor roller and pulley shafts in inch-frame machinery", "utility-vehicle differential and pinion supports", "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 23.812 mm (0.937 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-1779/1729 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 23.812 mm bore (56.896×19.368 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 1779/1729 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 19.368 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 23.812 mm is 0.937 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Shaft and housing fillets must clear the ring chamfers of 1779 and 1729; use undercut shoulders so the rings seat on the face, not on a radius.", "The 47.5/46.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-1779/1729; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-1779/1729?", "a": "4T-1779/1729 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 23.812 mm bore (0.937 in), 56.896 mm outside diameter and 19.368 mm assembled width T (2.24 × 0.763 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 47.5 kN, C0 46.5 kN, grease limiting speed 7,200 r/min, oil speed 9,600 r/min, mass about 244 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-1779/1729 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 1779 cone or the 1729 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 47.5/46.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-1779/1729 and a metric ISO 355 tapered bearing?", "a": "4T-1779/1729 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 23.812×56.896×19.368 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-1779/1729 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 1779/1729 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-1779/1729 list two speeds, 7,200 and 9,600 r/min?", "a": "The lower figure, 7,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-1779/1729 at 9,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "1779", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-1779-1729", "1779-1729", "4T-1779-1729" ], "locale_variants": {} }, { "sku": "07098-07196", "brand": "NTN", "manufacturer_designation": "NTN 4T-07098/07196", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 24.981, "D_mm": 50.005, "B_mm": 13.495, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 28.8, "static_load_kN": 27.9, "limiting_speed_rpm": 7500, "max_rpm": 7500, "speed_oil_rpm": 10000, "weight_g": 121, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 24.981 mm carrying combined radial and thrust load, NTN lists 4T-07098/07196, a single-row 4T tapered roller set of 28.8 kN C and 27.9 kN C0 inside the 50.005 mm OD cup. Cone and cup of 4T-07098/07196 are separately stocked parts: a worn 07196 cup can be replaced against the existing 07098 cone, provided the new cup carries the identical reference — pairing across references changes the 13.495 mm assembled width and the rating. Imperial cross-check for the drawing: 24.981×50.005×13.495 mm converts to 0.984 × 1.969 × 0.531 in; the ABMA envelope swaps with like-numbered inch parts but the 28.8/27.9 kN ratings are NTN-specific. The printed 28.8/27.9 kN ratings belong to the assembled 07098+07196 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-07098/07196; reverse the fit logic when the cup rotates.", "applications": [ "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions", "small inch-shaft gearbox and reducer shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 24.981 mm (0.984 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-07098/07196 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 24.981 mm bore (50.005×13.495 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 07098/07196 reference at purchase.", "An unloaded 4T-07098/07196 near 7,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Open 4T-07098/07196 sets have no seals: a hub or gearbox needs external sealing or the 7,500 r/min grease figure is meaningless once water reaches the cone rib.", "Quote the full 07098/07196 pair at ordering: the 07098 cone also ships against sibling cups, and a cup from another reference changes the 13.495 mm assembled width and the rating.", "The 28.8/27.9 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-07098/07196; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-07098/07196?", "a": "4T-07098/07196 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 24.981 mm bore (0.984 in), 50.005 mm outside diameter and 13.495 mm assembled width T (1.969 × 0.531 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 28.8 kN, C0 27.9 kN, grease limiting speed 7,500 r/min, oil speed 10,000 r/min, mass about 121 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-07098/07196 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 07098 cone or the 07196 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 28.8/27.9 kN ratings change with the cup." }, { "q": "What is the difference between 4T-07098/07196 and a metric ISO 355 tapered bearing?", "a": "4T-07098/07196 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 24.981×50.005×13.495 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-07098/07196 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 07098/07196 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-07098/07196 list two speeds, 7,500 and 10,000 r/min?", "a": "The lower figure, 7,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-07098/07196 at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "07098", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-07098-07196", "07098-07196", "4T-07098-07196" ], "locale_variants": {} }, { "sku": "07097-07196", "brand": "NTN", "manufacturer_designation": "NTN 4T-07097/07196", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25, "D_mm": 50.005, "B_mm": 13.495, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 28.8, "static_load_kN": 27.9, "limiting_speed_rpm": 7500, "max_rpm": 7500, "speed_oil_rpm": 10000, "weight_g": 116, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-07097/07196 at 25 mm bore (0.984 in), 50.005 mm cup OD and 13.495 mm assembled T, with a grease limiting speed of 7,500 r/min and an oil ceiling of 10,000 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 07097 sits in the pure-numeric inch family. The 12.5 mm radial section over the 25 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 07196: within the pure-numeric inch family tables the 07097 cone is listed against several cup options, and it is the cup that fixes the 50.005 mm OD and the 13.495 mm assembled width — quote the full 07097/07196 pair, never the cone alone. Mount the 25 mm cone with an induction heater (max 120 °C) and press the 50.005 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "small machine-tool feed and spindle counter-supports", "light trailer and boat-trailer wheel hubs", "small agricultural implement wheels and auger drives", "lawn, garden and powersport axle positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 25 mm (0.984 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-07097/07196 pair with a dial indicator on end play rather than by locknut feel.", "The pure-numeric inch family at 25 mm bore (50.005×13.495 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 07097/07196 reference at purchase.", "An unloaded 4T-07097/07196 near 7,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Never drive the 50.005 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 4T-07097/07196 sets have no seals: a hub or gearbox needs external sealing or the 7,500 r/min grease figure is meaningless once water reaches the cone rib.", "The 28.8/27.9 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-07097/07196; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-07097/07196?", "a": "4T-07097/07196 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25 mm bore (0.984 in), 50.005 mm outside diameter and 13.495 mm assembled width T (1.969 × 0.531 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 28.8 kN, C0 27.9 kN, grease limiting speed 7,500 r/min, oil speed 10,000 r/min, mass about 116 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-07097/07196 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 07097 cone or the 07196 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 28.8/27.9 kN ratings change with the cup." }, { "q": "What is the difference between 4T-07097/07196 and a metric ISO 355 tapered bearing?", "a": "4T-07097/07196 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25×50.005×13.495 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-07097/07196 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 07097/07196 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-07097/07196 list two speeds, 7,500 and 10,000 r/min?", "a": "The lower figure, 7,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-07097/07196 at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "07097", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-07097-07196", "07097-07196", "4T-07097-07196" ], "locale_variants": {} }, { "sku": "07096-07196", "brand": "NTN", "manufacturer_designation": "NTN 4T-07096/07196", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.159, "D_mm": 50.005, "B_mm": 13.495, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 28.8, "static_load_kN": 27.9, "limiting_speed_rpm": 7500, "max_rpm": 7500, "speed_oil_rpm": 10000, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-07096/07196 is the NTN 4T catalogue entry for a 25.159×50.005×13.495 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-07096/07196 are separately stocked parts: a worn 07196 cup can be replaced against the existing 07096 cone, provided the new cup carries the identical reference — pairing across references changes the 13.495 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 7,500 r/min is the mechanical ceiling for 4T-07096/07196, oil 10,000 r/min with circulating oil — a 2,500 r/min margin at this size. Cup-side note for 07196: within the pure-numeric inch family tables the 07096 cone is listed against several cup options, and it is the cup that fixes the 50.005 mm OD and the 13.495 mm assembled width — quote the full 07096/07196 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-07096/07196 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 25.159 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-07096/07196.", "The pure-numeric inch family at 25.159 mm bore (50.005×13.495 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 07096/07196 reference at purchase.", "Inch and metric bores collide on paper — 25.159 mm is 0.991 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Quote the full 07096/07196 pair at ordering: the 07096 cone also ships against sibling cups, and a cup from another reference changes the 13.495 mm assembled width and the rating.", "Quote the full 07096/07196 pair at ordering: the 07096 cone also ships against sibling cups, and a cup from another reference changes the 13.495 mm assembled width and the rating.", "The 28.8/27.9 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-07096/07196; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-07096/07196?", "a": "4T-07096/07196 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.159 mm bore (0.991 in), 50.005 mm outside diameter and 13.495 mm assembled width T (1.969 × 0.531 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 28.8 kN, C0 27.9 kN, grease limiting speed 7,500 r/min, oil speed 10,000 r/min, mass about 120 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-07096/07196 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 07096 cone or the 07196 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 28.8/27.9 kN ratings change with the cup." }, { "q": "What is the difference between 4T-07096/07196 and a metric ISO 355 tapered bearing?", "a": "4T-07096/07196 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.159×50.005×13.495 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-07096/07196 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 07096/07196 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-07096/07196 list two speeds, 7,500 and 10,000 r/min?", "a": "The lower figure, 7,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-07096/07196 at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "07096", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-07096-07196", "07096-07196", "4T-07096-07196" ], "locale_variants": {} }, { "sku": "07100-07196", "brand": "NTN", "manufacturer_designation": "NTN 4T-07100/07196", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 50.005, "B_mm": 13.495, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 28.8, "static_load_kN": 27.9, "limiting_speed_rpm": 7500, "max_rpm": 7500, "speed_oil_rpm": 10000, "weight_g": 114, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-07100/07196 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 07100 and cup 07196 delivered as a matched, separable pair of 25.4 mm bore and 50.005 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 07100 sits in the pure-numeric inch family. Catalogue mass of the 4T-07100/07196 cone-plus-cup set is 114 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-07100/07196: press the 07196 cup square into the 50.005 mm seat first, then bring the 07100 cone (on its 25.4 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 25.4 mm cone with an induction heater (max 120 °C) and press the 50.005 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-07100/07196.", "The pure-numeric inch family at 25.4 mm bore (50.005×13.495 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 07100/07196 reference at purchase.", "An unloaded 4T-07100/07196 near 7,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of 07100 and 07196; use undercut shoulders so the rings seat on the face, not on a radius.", "Never drive the 50.005 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 28.8/27.9 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-07100/07196; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-07100/07196?", "a": "4T-07100/07196 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 50.005 mm outside diameter and 13.495 mm assembled width T (1.969 × 0.531 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 28.8 kN, C0 27.9 kN, grease limiting speed 7,500 r/min, oil speed 10,000 r/min, mass about 114 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-07100/07196 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 07100 cone or the 07196 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 28.8/27.9 kN ratings change with the cup." }, { "q": "What is the difference between 4T-07100/07196 and a metric ISO 355 tapered bearing?", "a": "4T-07100/07196 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×50.005×13.495 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-07100/07196 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 07100/07196 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-07100/07196 list two speeds, 7,500 and 10,000 r/min?", "a": "The lower figure, 7,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-07100/07196 at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "07100-07204", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-07100 paired with a different cup (07204): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-07100-07196", "07100-07196", "4T-07100-07196" ], "locale_variants": {} }, { "sku": "07100S-07196", "brand": "NTN", "manufacturer_designation": "NTN 4T-07100S/07196", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 50.005, "B_mm": 13.495, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 28.8, "static_load_kN": 27.9, "limiting_speed_rpm": 7500, "max_rpm": 7500, "speed_oil_rpm": 10000, "weight_g": 114, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-07100S/07196 at 25.4 mm bore (1 in), 50.005 mm cup OD and 13.495 mm assembled T, with a grease limiting speed of 7,500 r/min and an oil ceiling of 10,000 r/min. Cone and cup of 4T-07100S/07196 are separately stocked parts: a worn 07196 cup can be replaced against the existing 07100S cone, provided the new cup carries the identical reference — pairing across references changes the 13.495 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 7,500 r/min is the mechanical ceiling for 4T-07100S/07196, oil 10,000 r/min with circulating oil — a 2,500 r/min margin at this size. Cup-side note for 07196: within the pure-numeric inch family tables the 07100S cone is listed against several cup options, and it is the cup that fixes the 50.005 mm OD and the 13.495 mm assembled width — quote the full 07100S/07196 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-07100S/07196 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-07100S/07196.", "The pure-numeric inch family at 25.4 mm bore (50.005×13.495 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 07100S/07196 reference at purchase.", "ABMA makes the 25.4×50.005 mm envelope interchangeable, not the ratings: NTN prints 28.8/27.9 kN for this execution and another make of the same number can differ in roller complement.", "Fit selection follows the rotating ring: a rotating cone on a 25.4 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "An unloaded 4T-07100S/07196 near 7,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 28.8/27.9 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-07100S/07196; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-07100S/07196?", "a": "4T-07100S/07196 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 50.005 mm outside diameter and 13.495 mm assembled width T (1.969 × 0.531 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 28.8 kN, C0 27.9 kN, grease limiting speed 7,500 r/min, oil speed 10,000 r/min, mass about 114 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-07100S/07196 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 07100S cone or the 07196 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 28.8/27.9 kN ratings change with the cup." }, { "q": "What is the difference between 4T-07100S/07196 and a metric ISO 355 tapered bearing?", "a": "4T-07100S/07196 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×50.005×13.495 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-07100S/07196 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 07100S/07196 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-07100S/07196 list two speeds, 7,500 and 10,000 r/min?", "a": "The lower figure, 7,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-07100S/07196 at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "07100S", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "07100s-07196", "4t-07100s-07196", "07100S-07196", "4T-07100S-07196" ], "locale_variants": {} }, { "sku": "L44643-L44610", "brand": "NTN", "manufacturer_designation": "NTN 4T-L44643/L44610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 50.292, "B_mm": 14.224, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 32, "static_load_kN": 34, "limiting_speed_rpm": 7400, "max_rpm": 7400, "speed_oil_rpm": 9900, "weight_g": 130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-L44643/L44610 is the NTN 4T catalogue entry for a 25.4×50.292×14.224 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — L44643 sits in the light L family. Imperial cross-check for the drawing: 25.4×50.292×14.224 mm converts to 1 × 1.98 × 0.56 in; the ABMA envelope swaps with like-numbered inch parts but the 32/34 kN ratings are NTN-specific. The printed 32/34 kN ratings belong to the assembled L44643+L44610 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 25.4 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-L44643/L44610.", "The light L family at 25.4 mm bore (50.292×14.224 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L44643/L44610 reference at purchase.", "Never drive the 50.292 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Replacing one half of an adjusted pair without resetting end play negates the 14.224 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Grease packs must leave free volume inside the 14.224 mm-wide set; over-greasing a pair churning near the oil-band speed of 9,900 r/min raises temperature and destroys the setting.", "The 32/34 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L44643/L44610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L44643/L44610?", "a": "4T-L44643/L44610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 50.292 mm outside diameter and 14.224 mm assembled width T (1.98 × 0.56 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 32 kN, C0 34 kN, grease limiting speed 7,400 r/min, oil speed 9,900 r/min, mass about 130 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L44643/L44610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L44643 cone or the L44610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 32/34 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L44643/L44610 and a metric ISO 355 tapered bearing?", "a": "4T-L44643/L44610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×50.292×14.224 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L44643/L44610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L44643/L44610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L44643/L44610 list two speeds, 7,400 and 9,900 r/min?", "a": "The lower figure, 7,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L44643/L44610 at 9,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L44643-610", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4×50.292×14.224 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l44643-l44610", "l44643-l44610", "L44643-L44610", "4T-L44643-L44610" ], "locale_variants": {} }, { "sku": "07100-07204", "brand": "NTN", "manufacturer_designation": "NTN 4T-07100/07204", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 51.994, "B_mm": 15.011, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 28.8, "static_load_kN": 27.9, "limiting_speed_rpm": 7500, "max_rpm": 7500, "speed_oil_rpm": 10000, "weight_g": 141, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1 in (25.4 mm) shaft position as 4T-07100/07204: cone 07100, cup 07204, profiled rollers and a pressed-steel cage, rated 28.8 kN basic dynamic and 27.9 kN static. Reading the designation: 4T-07100/07204 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 13.3 mm radial section over the 25.4 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-07100/07204: press the 07204 cup square into the 51.994 mm seat first, then bring the 07100 cone (on its 25.4 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 25.4 mm cone with an induction heater (max 120 °C) and press the 51.994 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-07100/07204.", "The pure-numeric inch family at 25.4 mm bore (51.994×15.011 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 07100/07204 reference at purchase.", "An unloaded 4T-07100/07204 near 7,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 15.011 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (15.011 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 28.8/27.9 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-07100/07204; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-07100/07204?", "a": "4T-07100/07204 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 51.994 mm outside diameter and 15.011 mm assembled width T (2.047 × 0.591 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 28.8 kN, C0 27.9 kN, grease limiting speed 7,500 r/min, oil speed 10,000 r/min, mass about 141 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-07100/07204 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 07100 cone or the 07204 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 28.8/27.9 kN ratings change with the cup." }, { "q": "What is the difference between 4T-07100/07204 and a metric ISO 355 tapered bearing?", "a": "4T-07100/07204 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×51.994×15.011 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-07100/07204 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 07100/07204 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-07100/07204 list two speeds, 7,500 and 10,000 r/min?", "a": "The lower figure, 7,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-07100/07204 at 10,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "07100-07196", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-07100 paired with a different cup (07196): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-07100-07204", "07100-07204", "4T-07100-07204" ], "locale_variants": {} }, { "sku": "1780-1729", "brand": "NTN", "manufacturer_designation": "NTN 4T-1780/1729", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 56.896, "B_mm": 19.368, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 47.5, "static_load_kN": 46.5, "limiting_speed_rpm": 7200, "max_rpm": 7200, "speed_oil_rpm": 9600, "weight_g": 234, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-1780/1729 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 25.4×56.896×19.368 mm (assembled width T), for a shaft of about 25.4 mm (1 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 1780 sits in the pure-numeric inch family. Contact-angle geometry of the pure-numeric inch family gives 4T-1780/1729 its radial/axial load split — at 47.5/46.5 kN the static rating is about 0.98× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-1780/1729: press the 1729 cup square into the 56.896 mm seat first, then bring the 1780 cone (on its 25.4 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 25.4 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-1780/1729.", "The pure-numeric inch family at 25.4 mm bore (56.896×19.368 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 1780/1729 reference at purchase.", "ABMA makes the 25.4×56.896 mm envelope interchangeable, not the ratings: NTN prints 47.5/46.5 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 25.4×56.896 mm envelope interchangeable, not the ratings: NTN prints 47.5/46.5 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 25.4×56.896 mm envelope interchangeable, not the ratings: NTN prints 47.5/46.5 kN for this execution and another make of the same number can differ in roller complement.", "The 47.5/46.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-1780/1729; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-1780/1729?", "a": "4T-1780/1729 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 56.896 mm outside diameter and 19.368 mm assembled width T (2.24 × 0.763 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 47.5 kN, C0 46.5 kN, grease limiting speed 7,200 r/min, oil speed 9,600 r/min, mass about 234 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-1780/1729 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 1780 cone or the 1729 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 47.5/46.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-1780/1729 and a metric ISO 355 tapered bearing?", "a": "4T-1780/1729 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×56.896×19.368 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-1780/1729 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 1780/1729 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-1780/1729 list two speeds, 7,200 and 9,600 r/min?", "a": "The lower figure, 7,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-1780/1729 at 9,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "1780", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-1780-1729", "1780-1729", "4T-1780-1729" ], "locale_variants": {} }, { "sku": "M84548-M84510", "brand": "NTN", "manufacturer_designation": "NTN 4T-M84548/M84510", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 57.15, "B_mm": 19.431, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 47, "static_load_kN": 48.5, "limiting_speed_rpm": 6900, "max_rpm": 6900, "speed_oil_rpm": 9200, "weight_g": 244, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1 in (25.4 mm) shaft position as 4T-M84548/M84510: cone M84548, cup M84510, profiled rollers and a pressed-steel cage, rated 47 kN basic dynamic and 48.5 kN static. Cone and cup of 4T-M84548/M84510 are separately stocked parts: a worn M84510 cup can be replaced against the existing M84548 cone, provided the new cup carries the identical reference — pairing across references changes the 19.431 mm assembled width and the rating. Catalogue mass of the 4T-M84548/M84510 cone-plus-cup set is 244 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for M84510: within the medium M family tables the M84548 cone is listed against several cup options, and it is the cup that fixes the 57.15 mm OD and the 19.431 mm assembled width — quote the full M84548/M84510 pair, never the cone alone. Running clearance of 4T-M84548/M84510 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-M84548/M84510.", "The medium M family at 25.4 mm bore (57.15×19.431 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full M84548/M84510 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 19.431 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-M84548/M84510 sets have no seals: a hub or gearbox needs external sealing or the 6,900 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 25.4×57.15 mm envelope interchangeable, not the ratings: NTN prints 47/48.5 kN for this execution and another make of the same number can differ in roller complement.", "The 47/48.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-M84548/M84510; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-M84548/M84510?", "a": "4T-M84548/M84510 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 57.15 mm outside diameter and 19.431 mm assembled width T (2.25 × 0.765 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 47 kN, C0 48.5 kN, grease limiting speed 6,900 r/min, oil speed 9,200 r/min, mass about 244 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-M84548/M84510 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the M84548 cone or the M84510 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 47/48.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-M84548/M84510 and a metric ISO 355 tapered bearing?", "a": "4T-M84548/M84510 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×57.15×19.431 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-M84548/M84510 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare M84548/M84510 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-M84548/M84510 list two speeds, 6,900 and 9,200 r/min?", "a": "The lower figure, 6,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-M84548/M84510 at 9,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "M84548-510", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-m84548-m84510", "m84548-m84510", "M84548-M84510", "4T-M84548-M84510" ], "locale_variants": {} }, { "sku": "15101-15243", "brand": "NTN", "manufacturer_designation": "NTN 4T-15101/15243", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 61.912, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 301, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-15101/15243 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 25.4×61.912×19.05 mm (assembled width T), for a shaft of about 25.4 mm (1 in). Reading the designation: 4T-15101/15243 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 18.3 mm radial section over the 25.4 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-15101/15243: press the 15243 cup square into the 61.912 mm seat first, then bring the 15101 cone (on its 25.4 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-15101/15243 run near 6,100 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15101/15243.", "The pure-numeric inch family at 25.4 mm bore (61.912×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15101/15243 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 25.4 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Never drive the 61.912 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Quote the full 15101/15243 pair at ordering: the 15101 cone also ships against sibling cups, and a cup from another reference changes the 19.05 mm assembled width and the rating.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15101/15243; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15101/15243?", "a": "4T-15101/15243 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 61.912 mm outside diameter and 19.05 mm assembled width T (2.437 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 301 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15101/15243 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15101 cone or the 15243 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15101/15243 and a metric ISO 355 tapered bearing?", "a": "4T-15101/15243 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×61.912×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15101/15243 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15101/15243 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15101/15243 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15101/15243 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15101-15245", "equiv_brand": "SKF", "level": "partial", "note": "Same 25.4×61.912×19.05 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15101-15243", "15101-15243", "4T-15101-15243" ], "locale_variants": {} }, { "sku": "15100-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15100/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 301, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-15100/15245 is the NTN 4T catalogue entry for a 25.4×62×19.05 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 15100 identifies the cone of 25.4 mm (1 in) bore by catalogue lookup, and 15245 fixes the 62 mm OD. The 2.0 kN of dynamic capacity per millimetre of bore summarises the 52 kN rating over the 25.4 mm bore — sanity-check any interchange candidate against this ratio and the 19.05 mm T. Cup-side note for 15245: within the pure-numeric inch family tables the 15100 cone is listed against several cup options, and it is the cup that fixes the 62 mm OD and the 19.05 mm assembled width — quote the full 15100/15245 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 25.4 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15100/15245.", "The pure-numeric inch family at 25.4 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15100/15245 reference at purchase.", "Grease packs must leave free volume inside the 19.05 mm-wide set; over-greasing a pair churning near the oil-band speed of 8,200 r/min raises temperature and destroys the setting.", "Open 4T-15100/15245 sets have no seals: a hub or gearbox needs external sealing or the 6,100 r/min grease figure is meaningless once water reaches the cone rib.", "Fit selection follows the rotating ring: a rotating cone on a 25.4 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15100/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15100/15245?", "a": "4T-15100/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 301 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15100/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15100 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15100/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15100/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15100/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15100/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15100/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15100/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15100", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15100-15245", "15100-15245", "4T-15100-15245" ], "locale_variants": {} }, { "sku": "15102-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15102/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 303, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-15102/15245 is the NTN 4T catalogue entry for a 25.4×62×19.05 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 15102 sits in the pure-numeric inch family. Selection: C 52 kN against C0 54 kN gives a C0/C ratio of 1.04 for the 25.4 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 15245: within the pure-numeric inch family tables the 15102 cone is listed against several cup options, and it is the cup that fixes the 62 mm OD and the 19.05 mm assembled width — quote the full 15102/15245 pair, never the cone alone. Running clearance of 4T-15102/15245 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15102/15245.", "The pure-numeric inch family at 25.4 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15102/15245 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 15102 and 15245; use undercut shoulders so the rings seat on the face, not on a radius.", "ABMA makes the 25.4×62 mm envelope interchangeable, not the ratings: NTN prints 52/54 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 15102/15245 pair at ordering: the 15102 cone also ships against sibling cups, and a cup from another reference changes the 19.05 mm assembled width and the rating.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15102/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15102/15245?", "a": "4T-15102/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 303 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15102/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15102 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15102/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15102/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15102/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15102/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15102/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15102/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15102", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15102-15245", "15102-15245", "4T-15102-15245" ], "locale_variants": {} }, { "sku": "M86643-M86610", "brand": "NTN", "manufacturer_designation": "NTN 4T-M86643/M86610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 64.292, "B_mm": 21.433, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 57.5, "static_load_kN": 64.5, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8100, "weight_g": 372, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 25.4 mm carrying combined radial and thrust load, NTN lists 4T-M86643/M86610, a single-row 4T tapered roller set of 57.5 kN C and 64.5 kN C0 inside the 64.292 mm OD cup. Cone and cup of 4T-M86643/M86610 are separately stocked parts: a worn M86610 cup can be replaced against the existing M86643 cone, provided the new cup carries the identical reference — pairing across references changes the 21.433 mm assembled width and the rating. Selection: C 57.5 kN against C0 64.5 kN gives a C0/C ratio of 1.12 for the 25.4 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 57.5/64.5 kN ratings belong to the assembled M86643+M86610 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-M86643/M86610 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-M86643/M86610.", "The medium M family at 25.4 mm bore (64.292×21.433 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full M86643/M86610 reference at purchase.", "Grease packs must leave free volume inside the 21.433 mm-wide set; over-greasing a pair churning near the oil-band speed of 8,100 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of M86643 and M86610; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 25.4 mm is 1 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 57.5/64.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-M86643/M86610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-M86643/M86610?", "a": "4T-M86643/M86610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 64.292 mm outside diameter and 21.433 mm assembled width T (2.531 × 0.844 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 57.5 kN, C0 64.5 kN, grease limiting speed 6,100 r/min, oil speed 8,100 r/min, mass about 372 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-M86643/M86610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the M86643 cone or the M86610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 57.5/64.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-M86643/M86610 and a metric ISO 355 tapered bearing?", "a": "4T-M86643/M86610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×64.292×21.433 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-M86643/M86610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare M86643/M86610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-M86643/M86610 list two speeds, 6,100 and 8,100 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-M86643/M86610 at 8,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "M86643", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-m86643-m86610", "m86643-m86610", "M86643-M86610", "4T-M86643-M86610" ], "locale_variants": {} }, { "sku": "23100-23256", "brand": "NTN", "manufacturer_designation": "NTN 4T-23100/23256", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 65.088, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 50.5, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 363, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-23100/23256 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 25.4×65.088×22.225 mm (assembled width T), for a shaft of about 25.4 mm (1 in). Reading the designation: 4T-23100/23256 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 25.4×65.088×22.225 mm converts to 1 × 2.563 × 0.875 in; the ABMA envelope swaps with like-numbered inch parts but the 52/50.5 kN ratings are NTN-specific. Cup-side note for 23256: within the pure-numeric inch family tables the 23100 cone is listed against several cup options, and it is the cup that fixes the 65.088 mm OD and the 22.225 mm assembled width — quote the full 23100/23256 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-23100/23256; reverse the fit logic when the cup rotates.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-23100/23256.", "The pure-numeric inch family at 25.4 mm bore (65.088×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 23100/23256 reference at purchase.", "An unloaded 4T-23100/23256 near 5,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Never drive the 65.088 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume inside the 22.225 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,600 r/min raises temperature and destroys the setting.", "The 52/50.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-23100/23256; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-23100/23256?", "a": "4T-23100/23256 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 65.088 mm outside diameter and 22.225 mm assembled width T (2.563 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 50.5 kN, grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 363 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-23100/23256 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 23100 cone or the 23256 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/50.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-23100/23256 and a metric ISO 355 tapered bearing?", "a": "4T-23100/23256 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×65.088×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-23100/23256 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 23100/23256 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-23100/23256 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-23100/23256 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "23100", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-23100-23256", "23100-23256", "4T-23100-23256" ], "locale_variants": {} }, { "sku": "2687-2631", "brand": "NTN", "manufacturer_designation": "NTN 4T-2687/2631", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 25.4, "D_mm": 66.421, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 71.5, "static_load_kN": 72.5, "limiting_speed_rpm": 6200, "max_rpm": 6200, "speed_oil_rpm": 8200, "weight_g": 444, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-2687/2631 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-2687/2631 are separately stocked parts: a worn 2631 cup can be replaced against the existing 2687 cone, provided the new cup carries the identical reference — pairing across references changes the 23.812 mm assembled width and the rating. The 20.5 mm radial section over the 25.4 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 2631: within the pure-numeric inch family tables the 2687 cone is listed against several cup options, and it is the cup that fixes the 66.421 mm OD and the 23.812 mm assembled width — quote the full 2687/2631 pair, never the cone alone. Fillet radii must clear the chamfers of the 2687 cone and 2631 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 25.4 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2687/2631.", "The pure-numeric inch family at 25.4 mm bore (66.421×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2687/2631 reference at purchase.", "Grease packs must leave free volume inside the 23.812 mm-wide set; over-greasing a pair churning near the oil-band speed of 8,200 r/min raises temperature and destroys the setting.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 25.4 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 71.5/72.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2687/2631; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2687/2631?", "a": "4T-2687/2631 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 25.4 mm bore (1 in), 66.421 mm outside diameter and 23.812 mm assembled width T (2.615 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 71.5 kN, C0 72.5 kN, grease limiting speed 6,200 r/min, oil speed 8,200 r/min, mass about 444 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2687/2631 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2687 cone or the 2631 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 71.5/72.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2687/2631 and a metric ISO 355 tapered bearing?", "a": "4T-2687/2631 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 25.4×66.421×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2687/2631 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2687/2631 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2687/2631 list two speeds, 6,200 and 8,200 r/min?", "a": "The lower figure, 6,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2687/2631 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2687", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2687-2631", "2687-2631", "4T-2687-2631" ], "locale_variants": {} }, { "sku": "15103-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15103/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 26.157, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.03 in (26.157 mm) shaft position as 4T-15103/15245: cone 15103, cup 15245, profiled rollers and a pressed-steel cage, rated 52 kN basic dynamic and 54 kN static. Reading the designation: 4T-15103/15245 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 17.9 mm radial section over the 26.157 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-15103/15245: press the 15245 cup square into the 62 mm seat first, then bring the 15103 cone (on its 26.157 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 26.157 mm cone with an induction heater (max 120 °C) and press the 62 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 26.157 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15103/15245.", "The pure-numeric inch family at 26.157 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15103/15245 reference at purchase.", "Do not confuse T (19.05 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 19.05 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (19.05 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15103/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15103/15245?", "a": "4T-15103/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 26.157 mm bore (1.03 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 300 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15103/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15103 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15103/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15103/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 26.157×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15103/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15103/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15103/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15103/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15103", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15103-15245", "15103-15245", "4T-15103-15245" ], "locale_variants": {} }, { "sku": "2682-2631", "brand": "NTN", "manufacturer_designation": "NTN 4T-2682/2631", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 26.162, "D_mm": 66.421, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 71.5, "static_load_kN": 72.5, "limiting_speed_rpm": 6200, "max_rpm": 6200, "speed_oil_rpm": 8200, "weight_g": 436, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-2682/2631 is the NTN 4T catalogue entry for a 26.162×66.421×23.812 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 2682 sits in the pure-numeric inch family. Grease relubrication at the 6,200 r/min limiting speed targets the cone-rib contact; sustaining 8,200 r/min needs an oil supply directed at the large roller ends. The printed 71.5/72.5 kN ratings belong to the assembled 2682+2631 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 2682 cone and 2631 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 26.162 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2682/2631.", "The pure-numeric inch family at 26.162 mm bore (66.421×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2682/2631 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 26.162 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Open 4T-2682/2631 sets have no seals: a hub or gearbox needs external sealing or the 6,200 r/min grease figure is meaningless once water reaches the cone rib.", "An unloaded 4T-2682/2631 near 6,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 71.5/72.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2682/2631; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2682/2631?", "a": "4T-2682/2631 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 26.162 mm bore (1.03 in), 66.421 mm outside diameter and 23.812 mm assembled width T (2.615 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 71.5 kN, C0 72.5 kN, grease limiting speed 6,200 r/min, oil speed 8,200 r/min, mass about 436 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2682/2631 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2682 cone or the 2631 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 71.5/72.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2682/2631 and a metric ISO 355 tapered bearing?", "a": "4T-2682/2631 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 26.162×66.421×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2682/2631 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2682/2631 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2682/2631 list two speeds, 6,200 and 8,200 r/min?", "a": "The lower figure, 6,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2682/2631 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2682", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2682-2631", "2682-2631", "4T-2682-2631" ], "locale_variants": {} }, { "sku": "L44649-L44610", "brand": "NTN", "manufacturer_designation": "NTN 4T-L44649/L44610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 26.988, "D_mm": 50.292, "B_mm": 14.224, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 32, "static_load_kN": 34, "limiting_speed_rpm": 7400, "max_rpm": 7400, "speed_oil_rpm": 9900, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-L44649/L44610 belongs to the NTN inch 4T tapered roller range (light L family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — L44649 sits in the light L family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 14.224 mm T of each 4T-L44649/L44610 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-L44649/L44610: press the L44610 cup square into the 50.292 mm seat first, then bring the L44649 cone (on its 26.988 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 26.988 mm cone with an induction heater (max 120 °C) and press the 50.292 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 26.988 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-L44649/L44610.", "The light L family at 26.988 mm bore (50.292×14.224 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L44649/L44610 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 14.224 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-L44649/L44610 sets have no seals: a hub or gearbox needs external sealing or the 7,400 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 14.224 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 32/34 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L44649/L44610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L44649/L44610?", "a": "4T-L44649/L44610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 26.988 mm bore (1.063 in), 50.292 mm outside diameter and 14.224 mm assembled width T (1.98 × 0.56 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 32 kN, C0 34 kN, grease limiting speed 7,400 r/min, oil speed 9,900 r/min, mass about 120 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L44649/L44610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L44649 cone or the L44610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 32/34 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L44649/L44610 and a metric ISO 355 tapered bearing?", "a": "4T-L44649/L44610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 26.988×50.292×14.224 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L44649/L44610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L44649/L44610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L44649/L44610 list two speeds, 7,400 and 9,900 r/min?", "a": "The lower figure, 7,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L44649/L44610 at 9,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L44649-610", "equiv_brand": "SKF", "level": "partial", "note": "Same 26.988×50.292×14.224 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l44649-l44610", "l44649-l44610", "L44649-L44610", "4T-L44649-L44610" ], "locale_variants": {} }, { "sku": "15580-15523", "brand": "NTN", "manufacturer_designation": "NTN 4T-15580/15523", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 26.988, "D_mm": 60.325, "B_mm": 19.842, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 44, "static_load_kN": 45.5, "limiting_speed_rpm": 6700, "max_rpm": 6700, "speed_oil_rpm": 8900, "weight_g": 261, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-15580/15523 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 26.988×60.325×19.842 mm (assembled width T), for a shaft of about 26.988 mm (1.063 in). Cone and cup of 4T-15580/15523 are separately stocked parts: a worn 15523 cup can be replaced against the existing 15580 cone, provided the new cup carries the identical reference — pairing across references changes the 19.842 mm assembled width and the rating. Imperial cross-check for the drawing: 26.988×60.325×19.842 mm converts to 1.063 × 2.375 × 0.781 in; the ABMA envelope swaps with like-numbered inch parts but the 44/45.5 kN ratings are NTN-specific. The printed 44/45.5 kN ratings belong to the assembled 15580+15523 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 15580 cone and 15523 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 26.988 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15580/15523.", "The pure-numeric inch family at 26.988 mm bore (60.325×19.842 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15580/15523 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 15580 and 15523; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-15580/15523 near 6,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Grease packs must leave free volume inside the 19.842 mm-wide set; over-greasing a pair churning near the oil-band speed of 8,900 r/min raises temperature and destroys the setting.", "The 44/45.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15580/15523; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15580/15523?", "a": "4T-15580/15523 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 26.988 mm bore (1.063 in), 60.325 mm outside diameter and 19.842 mm assembled width T (2.375 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 44 kN, C0 45.5 kN, grease limiting speed 6,700 r/min, oil speed 8,900 r/min, mass about 261 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15580/15523 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15580 cone or the 15523 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 44/45.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15580/15523 and a metric ISO 355 tapered bearing?", "a": "4T-15580/15523 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 26.988×60.325×19.842 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15580/15523 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15580/15523 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15580/15523 list two speeds, 6,700 and 8,900 r/min?", "a": "The lower figure, 6,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15580/15523 at 8,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15580", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15580-15523", "15580-15523", "4T-15580-15523" ], "locale_variants": {} }, { "sku": "15106-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15106/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 26.988, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 291, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-15106/15245 is the NTN 4T catalogue entry for a 26.988×62×19.05 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-15106/15245 are separately stocked parts: a worn 15245 cup can be replaced against the existing 15106 cone, provided the new cup carries the identical reference — pairing across references changes the 19.05 mm assembled width and the rating. Contact-angle geometry of the pure-numeric inch family gives 4T-15106/15245 its radial/axial load split — at 52/54 kN the static rating is about 1.04× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-15106/15245: press the 15245 cup square into the 62 mm seat first, then bring the 15106 cone (on its 26.988 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-15106/15245 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 26.988 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15106/15245.", "The pure-numeric inch family at 26.988 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15106/15245 reference at purchase.", "Quote the full 15106/15245 pair at ordering: the 15106 cone also ships against sibling cups, and a cup from another reference changes the 19.05 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 26.988 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 19.05 mm-wide set; over-greasing a pair churning near the oil-band speed of 8,200 r/min raises temperature and destroys the setting.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15106/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15106/15245?", "a": "4T-15106/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 26.988 mm bore (1.063 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 291 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15106/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15106 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15106/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15106/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 26.988×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15106/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15106/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15106/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15106/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15106", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15106-15245", "15106-15245", "4T-15106-15245" ], "locale_variants": {} }, { "sku": "2688-2631", "brand": "NTN", "manufacturer_designation": "NTN 4T-2688/2631", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 26.988, "D_mm": 66.421, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 71.5, "static_load_kN": 72.5, "limiting_speed_rpm": 6200, "max_rpm": 6200, "speed_oil_rpm": 8200, "weight_g": 429, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-2688/2631 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 2688 sits in the pure-numeric inch family. Selection: C 71.5 kN against C0 72.5 kN gives a C0/C ratio of 1.01 for the 26.988 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-2688/2631: press the 2631 cup square into the 66.421 mm seat first, then bring the 2688 cone (on its 26.988 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-2688/2631 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 26.988 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2688/2631.", "The pure-numeric inch family at 26.988 mm bore (66.421×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2688/2631 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 2688 and 2631; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of 2688 and 2631; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 23.812 mm-wide set; over-greasing a pair churning near the oil-band speed of 8,200 r/min raises temperature and destroys the setting.", "The 71.5/72.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2688/2631; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2688/2631?", "a": "4T-2688/2631 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 26.988 mm bore (1.063 in), 66.421 mm outside diameter and 23.812 mm assembled width T (2.615 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 71.5 kN, C0 72.5 kN, grease limiting speed 6,200 r/min, oil speed 8,200 r/min, mass about 429 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2688/2631 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2688 cone or the 2631 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 71.5/72.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2688/2631 and a metric ISO 355 tapered bearing?", "a": "4T-2688/2631 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 26.988×66.421×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2688/2631 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2688/2631 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2688/2631 list two speeds, 6,200 and 8,200 r/min?", "a": "The lower figure, 6,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2688/2631 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2688", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2688-2631", "2688-2631", "4T-2688-2631" ], "locale_variants": {} }, { "sku": "1985-1930", "brand": "NTN", "manufacturer_designation": "NTN 4T-1985/1930", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 56.896, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 45, "static_load_kN": 44.5, "limiting_speed_rpm": 6700, "max_rpm": 6700, "speed_oil_rpm": 8900, "weight_g": 217, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 28.575 mm carrying combined radial and thrust load, NTN lists 4T-1985/1930, a single-row 4T tapered roller set of 45 kN C and 44.5 kN C0 inside the 56.896 mm OD cup. Cone and cup of 4T-1985/1930 are separately stocked parts: a worn 1930 cup can be replaced against the existing 1985 cone, provided the new cup carries the identical reference — pairing across references changes the 19.845 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 19.845 mm T of each 4T-1985/1930 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 45/44.5 kN ratings belong to the assembled 1985+1930 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-1985/1930 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-1985/1930.", "The pure-numeric inch family at 28.575 mm bore (56.896×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 1985/1930 reference at purchase.", "Do not confuse T (19.845 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Shaft and housing fillets must clear the ring chamfers of 1985 and 1930; use undercut shoulders so the rings seat on the face, not on a radius.", "Do not confuse T (19.845 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 45/44.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-1985/1930; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-1985/1930?", "a": "4T-1985/1930 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 56.896 mm outside diameter and 19.845 mm assembled width T (2.24 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 45 kN, C0 44.5 kN, grease limiting speed 6,700 r/min, oil speed 8,900 r/min, mass about 217 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-1985/1930 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 1985 cone or the 1930 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 45/44.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-1985/1930 and a metric ISO 355 tapered bearing?", "a": "4T-1985/1930 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×56.896×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-1985/1930 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 1985/1930 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-1985/1930 list two speeds, 6,700 and 8,900 r/min?", "a": "The lower figure, 6,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-1985/1930 at 8,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "1985-1922", "equiv_brand": "SKF", "level": "partial", "note": "Same 28.575×56.896×19.845 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "1985-1932", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-1985 paired with a different cup (1932): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "1985-1931", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-1985 paired with a different cup (1931): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-1985-1930", "1985-1930", "4T-1985-1930" ], "locale_variants": {} }, { "sku": "15590-15520", "brand": "NTN", "manufacturer_designation": "NTN 4T-15590/15520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 57.15, "B_mm": 17.462, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 44, "static_load_kN": 45.5, "limiting_speed_rpm": 6700, "max_rpm": 6700, "speed_oil_rpm": 8900, "weight_g": 197, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-15590/15520 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 15590 sits in the pure-numeric inch family. Selection: C 44 kN against C0 45.5 kN gives a C0/C ratio of 1.03 for the 28.575 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 44/45.5 kN ratings belong to the assembled 15590+15520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 28.575 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15590/15520.", "The pure-numeric inch family at 28.575 mm bore (57.15×17.462 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15590/15520 reference at purchase.", "Do not confuse T (17.462 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Do not confuse T (17.462 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "ABMA makes the 28.575×57.15 mm envelope interchangeable, not the ratings: NTN prints 44/45.5 kN for this execution and another make of the same number can differ in roller complement.", "The 44/45.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15590/15520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15590/15520?", "a": "4T-15590/15520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 57.15 mm outside diameter and 17.462 mm assembled width T (2.25 × 0.687 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 44 kN, C0 45.5 kN, grease limiting speed 6,700 r/min, oil speed 8,900 r/min, mass about 197 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15590/15520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15590 cone or the 15520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 44/45.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15590/15520 and a metric ISO 355 tapered bearing?", "a": "4T-15590/15520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×57.15×17.462 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15590/15520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15590/15520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15590/15520 list two speeds, 6,700 and 8,900 r/min?", "a": "The lower figure, 6,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15590/15520 at 8,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15590-15523", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-15590 paired with a different cup (15523): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=176", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15590-15520", "15590-15520", "4T-15590-15520" ], "locale_variants": {} }, { "sku": "1985-1932", "brand": "NTN", "manufacturer_designation": "NTN 4T-1985/1932", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 58.738, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 45, "static_load_kN": 44.5, "limiting_speed_rpm": 6700, "max_rpm": 6700, "speed_oil_rpm": 8900, "weight_g": 231, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-1985/1932 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 28.575×58.738×19.05 mm (assembled width T), for a shaft of about 28.575 mm (1.125 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 1985/1932 without it. Grease relubrication at the 6,700 r/min limiting speed targets the cone-rib contact; sustaining 8,900 r/min needs an oil supply directed at the large roller ends. The printed 45/44.5 kN ratings belong to the assembled 1985+1932 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-1985/1932 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-1985/1932.", "The pure-numeric inch family at 28.575 mm bore (58.738×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 1985/1932 reference at purchase.", "Grease packs must leave free volume inside the 19.05 mm-wide set; over-greasing a pair churning near the oil-band speed of 8,900 r/min raises temperature and destroys the setting.", "Quote the full 1985/1932 pair at ordering: the 1985 cone also ships against sibling cups, and a cup from another reference changes the 19.05 mm assembled width and the rating.", "An unloaded 4T-1985/1932 near 6,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 45/44.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-1985/1932; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-1985/1932?", "a": "4T-1985/1932 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 58.738 mm outside diameter and 19.05 mm assembled width T (2.313 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 45 kN, C0 44.5 kN, grease limiting speed 6,700 r/min, oil speed 8,900 r/min, mass about 231 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-1985/1932 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 1985 cone or the 1932 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 45/44.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-1985/1932 and a metric ISO 355 tapered bearing?", "a": "4T-1985/1932 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×58.738×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-1985/1932 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 1985/1932 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-1985/1932 list two speeds, 6,700 and 8,900 r/min?", "a": "The lower figure, 6,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-1985/1932 at 8,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "1985-1922", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "1985-1930", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-1985 paired with a different cup (1930): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "1985-1931", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-1985 paired with a different cup (1931): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-1985-1932", "1985-1932", "4T-1985-1932" ], "locale_variants": {} }, { "sku": "15590-15523", "brand": "NTN", "manufacturer_designation": "NTN 4T-15590/15523", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 60.325, "B_mm": 19.842, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 44, "static_load_kN": 45.5, "limiting_speed_rpm": 6700, "max_rpm": 6700, "speed_oil_rpm": 8900, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.125 in (28.575 mm) shaft position as 4T-15590/15523: cone 15590, cup 15523, profiled rollers and a pressed-steel cage, rated 44 kN basic dynamic and 45.5 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 15590/15523 without it. Catalogue mass of the 4T-15590/15523 cone-plus-cup set is 250 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 44/45.5 kN ratings belong to the assembled 15590+15523 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-15590/15523 run near 6,700 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15590/15523.", "The pure-numeric inch family at 28.575 mm bore (60.325×19.842 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15590/15523 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 28.575 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "An unloaded 4T-15590/15523 near 6,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (19.842 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 44/45.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15590/15523; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15590/15523?", "a": "4T-15590/15523 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 60.325 mm outside diameter and 19.842 mm assembled width T (2.375 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 44 kN, C0 45.5 kN, grease limiting speed 6,700 r/min, oil speed 8,900 r/min, mass about 250 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15590/15523 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15590 cone or the 15523 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 44/45.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15590/15523 and a metric ISO 355 tapered bearing?", "a": "4T-15590/15523 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×60.325×19.842 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15590/15523 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15590/15523 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15590/15523 list two speeds, 6,700 and 8,900 r/min?", "a": "The lower figure, 6,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15590/15523 at 8,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15590-15520", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-15590 paired with a different cup (15520): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15590-15523", "15590-15523", "4T-15590-15523" ], "locale_variants": {} }, { "sku": "1985-1931", "brand": "NTN", "manufacturer_designation": "NTN 4T-1985/1931", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 60.325, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 45, "static_load_kN": 44.5, "limiting_speed_rpm": 6700, "max_rpm": 6700, "speed_oil_rpm": 8900, "weight_g": 256, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-1985/1931 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 1985 identifies the cone of 28.575 mm (1.125 in) bore by catalogue lookup, and 1931 fixes the 60.325 mm OD. Imperial cross-check for the drawing: 28.575×60.325×19.845 mm converts to 1.125 × 2.375 × 0.781 in; the ABMA envelope swaps with like-numbered inch parts but the 45/44.5 kN ratings are NTN-specific. The printed 45/44.5 kN ratings belong to the assembled 1985+1931 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-1985/1931 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-1985/1931.", "The pure-numeric inch family at 28.575 mm bore (60.325×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 1985/1931 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 19.845 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 28.575 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 1985/1931 pair at ordering: the 1985 cone also ships against sibling cups, and a cup from another reference changes the 19.845 mm assembled width and the rating.", "The 45/44.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-1985/1931; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-1985/1931?", "a": "4T-1985/1931 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 60.325 mm outside diameter and 19.845 mm assembled width T (2.375 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 45 kN, C0 44.5 kN, grease limiting speed 6,700 r/min, oil speed 8,900 r/min, mass about 256 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-1985/1931 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 1985 cone or the 1931 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 45/44.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-1985/1931 and a metric ISO 355 tapered bearing?", "a": "4T-1985/1931 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×60.325×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-1985/1931 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 1985/1931 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-1985/1931 list two speeds, 6,700 and 8,900 r/min?", "a": "The lower figure, 6,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-1985/1931 at 8,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "1985-1922", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "1985-1930", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-1985 paired with a different cup (1930): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "1985-1932", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-1985 paired with a different cup (1932): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-1985-1931", "1985-1931", "4T-1985-1931" ], "locale_variants": {} }, { "sku": "15112-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15112/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 279, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 28.575 mm carrying combined radial and thrust load, NTN lists 4T-15112/15245, a single-row 4T tapered roller set of 52 kN C and 54 kN C0 inside the 62 mm OD cup. Reading the designation: 4T-15112/15245 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 19.05 mm T of each 4T-15112/15245 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 15245: within the pure-numeric inch family tables the 15112 cone is listed against several cup options, and it is the cup that fixes the 62 mm OD and the 19.05 mm assembled width — quote the full 15112/15245 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-15112/15245 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15112/15245.", "The pure-numeric inch family at 28.575 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15112/15245 reference at purchase.", "Do not confuse T (19.05 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "ABMA makes the 28.575×62 mm envelope interchangeable, not the ratings: NTN prints 52/54 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-15112/15245 near 6,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15112/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15112/15245?", "a": "4T-15112/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 279 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15112/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15112 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15112/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15112/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15112/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15112/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15112/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15112/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15112", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15112-15245", "15112-15245", "4T-15112-15245" ], "locale_variants": {} }, { "sku": "M86647-M86610", "brand": "NTN", "manufacturer_designation": "NTN 4T-M86647/M86610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 64.292, "B_mm": 21.433, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 57.5, "static_load_kN": 64.5, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8100, "weight_g": 348, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-M86647/M86610 at 28.575 mm bore (1.125 in), 64.292 mm cup OD and 21.433 mm assembled T, with a grease limiting speed of 6,100 r/min and an oil ceiling of 8,100 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote M86647/M86610 without it. Catalogue mass of the 4T-M86647/M86610 cone-plus-cup set is 348 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 57.5/64.5 kN ratings belong to the assembled M86647+M86610 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-M86647/M86610 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-M86647/M86610.", "The medium M family at 28.575 mm bore (64.292×21.433 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full M86647/M86610 reference at purchase.", "Quote the full M86647/M86610 pair at ordering: the M86647 cone also ships against sibling cups, and a cup from another reference changes the 21.433 mm assembled width and the rating.", "An unloaded 4T-M86647/M86610 near 6,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Never drive the 64.292 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 57.5/64.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-M86647/M86610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-M86647/M86610?", "a": "4T-M86647/M86610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 64.292 mm outside diameter and 21.433 mm assembled width T (2.531 × 0.844 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 57.5 kN, C0 64.5 kN, grease limiting speed 6,100 r/min, oil speed 8,100 r/min, mass about 348 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-M86647/M86610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the M86647 cone or the M86610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 57.5/64.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-M86647/M86610 and a metric ISO 355 tapered bearing?", "a": "4T-M86647/M86610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×64.292×21.433 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-M86647/M86610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare M86647/M86610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-M86647/M86610 list two speeds, 6,100 and 8,100 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-M86647/M86610 at 8,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "M86647-610", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-m86647-m86610", "m86647-m86610", "M86647-M86610", "4T-M86647-M86610" ], "locale_variants": {} }, { "sku": "2689-2631", "brand": "NTN", "manufacturer_designation": "NTN 4T-2689/2631", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 66.421, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 71.5, "static_load_kN": 72.5, "limiting_speed_rpm": 6200, "max_rpm": 6200, "speed_oil_rpm": 8200, "weight_g": 363, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-2689/2631 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-2689/2631 are separately stocked parts: a worn 2631 cup can be replaced against the existing 2689 cone, provided the new cup carries the identical reference — pairing across references changes the 23.812 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 6,200 r/min is the mechanical ceiling for 4T-2689/2631, oil 8,200 r/min with circulating oil — a 2,000 r/min margin at this size. Housing fitment sequence for 4T-2689/2631: press the 2631 cup square into the 66.421 mm seat first, then bring the 2689 cone (on its 28.575 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-2689/2631 run near 6,200 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2689/2631.", "The pure-numeric inch family at 28.575 mm bore (66.421×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2689/2631 reference at purchase.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Never drive the 66.421 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Quote the full 2689/2631 pair at ordering: the 2689 cone also ships against sibling cups, and a cup from another reference changes the 23.812 mm assembled width and the rating.", "The 71.5/72.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2689/2631; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2689/2631?", "a": "4T-2689/2631 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 66.421 mm outside diameter and 23.812 mm assembled width T (2.615 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 71.5 kN, C0 72.5 kN, grease limiting speed 6,200 r/min, oil speed 8,200 r/min, mass about 363 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2689/2631 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2689 cone or the 2631 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 71.5/72.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2689/2631 and a metric ISO 355 tapered bearing?", "a": "4T-2689/2631 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×66.421×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2689/2631 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2689/2631 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2689/2631 list two speeds, 6,200 and 8,200 r/min?", "a": "The lower figure, 6,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2689/2631 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2689", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2689-2631", "2689-2631", "4T-2689-2631" ], "locale_variants": {} }, { "sku": "02474-02420", "brand": "NTN", "manufacturer_designation": "NTN 4T-02474/02420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 68.262, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 63, "static_load_kN": 67, "limiting_speed_rpm": 5800, "max_rpm": 5800, "speed_oil_rpm": 7700, "weight_g": 410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-02474/02420 is the NTN 4T catalogue entry for a 28.575×68.262×22.225 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 02474/02420 without it. Speed planning uses both catalogue columns: grease 5,800 r/min is the mechanical ceiling for 4T-02474/02420, oil 7,700 r/min with circulating oil — a 1,900 r/min margin at this size. The printed 63/67 kN ratings belong to the assembled 02474+02420 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-02474/02420 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-02474/02420.", "The pure-numeric inch family at 28.575 mm bore (68.262×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 02474/02420 reference at purchase.", "An unloaded 4T-02474/02420 near 5,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Grease packs must leave free volume inside the 22.225 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,700 r/min raises temperature and destroys the setting.", "Never drive the 68.262 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 63/67 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-02474/02420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-02474/02420?", "a": "4T-02474/02420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 68.262 mm outside diameter and 22.225 mm assembled width T (2.687 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 63 kN, C0 67 kN, grease limiting speed 5,800 r/min, oil speed 7,700 r/min, mass about 410 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-02474/02420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 02474 cone or the 02420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 63/67 kN ratings change with the cup." }, { "q": "What is the difference between 4T-02474/02420 and a metric ISO 355 tapered bearing?", "a": "4T-02474/02420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×68.262×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-02474/02420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 02474/02420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-02474/02420 list two speeds, 5,800 and 7,700 r/min?", "a": "The lower figure, 5,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-02474/02420 at 7,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "02474", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-02474-02420", "02474-02420", "4T-02474-02420" ], "locale_variants": {} }, { "sku": "2474-2420", "brand": "NTN", "manufacturer_designation": "NTN 4T-2474/2420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 68.262, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 64, "static_load_kN": 65.5, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7700, "weight_g": 380, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-2474/2420 at 28.575 mm bore (1.125 in), 68.262 mm cup OD and 22.225 mm assembled T, with a grease limiting speed of 5,700 r/min and an oil ceiling of 7,700 r/min. Reading the designation: 4T-2474/2420 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Contact-angle geometry of the pure-numeric inch family gives 4T-2474/2420 its radial/axial load split — at 64/65.5 kN the static rating is about 1.02× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-2474/2420: press the 2420 cup square into the 68.262 mm seat first, then bring the 2474 cone (on its 28.575 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-2474/2420, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2474/2420.", "The pure-numeric inch family at 28.575 mm bore (68.262×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2474/2420 reference at purchase.", "An unloaded 4T-2474/2420 near 5,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of 2474 and 2420; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full 2474/2420 pair at ordering: the 2474 cone also ships against sibling cups, and a cup from another reference changes the 22.225 mm assembled width and the rating.", "The 64/65.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2474/2420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2474/2420?", "a": "4T-2474/2420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 68.262 mm outside diameter and 22.225 mm assembled width T (2.687 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 64 kN, C0 65.5 kN, grease limiting speed 5,700 r/min, oil speed 7,700 r/min, mass about 380 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2474/2420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2474 cone or the 2420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 64/65.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2474/2420 and a metric ISO 355 tapered bearing?", "a": "4T-2474/2420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×68.262×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2474/2420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2474/2420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2474/2420 list two speeds, 5,700 and 7,700 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2474/2420 at 7,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2474", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2474-2420", "2474-2420", "4T-2474-2420" ], "locale_variants": {} }, { "sku": "2578-2523", "brand": "NTN", "manufacturer_designation": "NTN 4T-2578/2523", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 69.85, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 76.5, "static_load_kN": 81.5, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 484, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-2578/2523 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 28.575×69.85×23.812 mm (assembled width T), for a shaft of about 28.575 mm (1.125 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 2578 sits in the pure-numeric inch family. The 20.6 mm radial section over the 28.575 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-2578/2523: press the 2523 cup square into the 69.85 mm seat first, then bring the 2578 cone (on its 28.575 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-2578/2523 run near 5,700 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2578/2523.", "The pure-numeric inch family at 28.575 mm bore (69.85×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2578/2523 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 28.575 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of 2578 and 2523; use undercut shoulders so the rings seat on the face, not on a radius.", "Fit selection follows the rotating ring: a rotating cone on a 28.575 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 76.5/81.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2578/2523; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2578/2523?", "a": "4T-2578/2523 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 69.85 mm outside diameter and 23.812 mm assembled width T (2.75 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 76.5 kN, C0 81.5 kN, grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 484 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2578/2523 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2578 cone or the 2523 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 76.5/81.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2578/2523 and a metric ISO 355 tapered bearing?", "a": "4T-2578/2523 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×69.85×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2578/2523 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2578/2523 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2578/2523 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2578/2523 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2578", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2578-2523", "2578-2523", "4T-2578-2523" ], "locale_variants": {} }, { "sku": "41125-41286", "brand": "NTN", "manufacturer_designation": "NTN 4T-41125/41286", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 72.626, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 64.5, "static_load_kN": 55.5, "limiting_speed_rpm": 5800, "max_rpm": 5800, "speed_oil_rpm": 7700, "weight_g": 475, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-41125/41286 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 41125 and cup 41286 delivered as a matched, separable pair of 28.575 mm bore and 72.626 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 41125 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 5,800 r/min is the mechanical ceiling for 4T-41125/41286, oil 7,700 r/min with circulating oil — a 1,900 r/min margin at this size. Cup-side note for 41286: within the pure-numeric inch family tables the 41125 cone is listed against several cup options, and it is the cup that fixes the 72.626 mm OD and the 24.608 mm assembled width — quote the full 41125/41286 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-41125/41286 run near 5,800 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-41125/41286.", "The pure-numeric inch family at 28.575 mm bore (72.626×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 41125/41286 reference at purchase.", "Quote the full 41125/41286 pair at ordering: the 41125 cone also ships against sibling cups, and a cup from another reference changes the 24.608 mm assembled width and the rating.", "ABMA makes the 28.575×72.626 mm envelope interchangeable, not the ratings: NTN prints 64.5/55.5 kN for this execution and another make of the same number can differ in roller complement.", "Shaft and housing fillets must clear the ring chamfers of 41125 and 41286; use undercut shoulders so the rings seat on the face, not on a radius.", "The 64.5/55.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-41125/41286; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-41125/41286?", "a": "4T-41125/41286 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 72.626 mm outside diameter and 24.608 mm assembled width T (2.859 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 64.5 kN, C0 55.5 kN, grease limiting speed 5,800 r/min, oil speed 7,700 r/min, mass about 475 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-41125/41286 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 41125 cone or the 41286 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 64.5/55.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-41125/41286 and a metric ISO 355 tapered bearing?", "a": "4T-41125/41286 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×72.626×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-41125/41286 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 41125/41286 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-41125/41286 list two speeds, 5,800 and 7,700 r/min?", "a": "The lower figure, 5,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-41125/41286 at 7,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "41125", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-41125-41286", "41125-41286", "4T-41125-41286" ], "locale_variants": {} }, { "sku": "02872-02820", "brand": "NTN", "manufacturer_designation": "NTN 4T-02872/02820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 28.575, "D_mm": 73.025, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 62.5, "static_load_kN": 68, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7000, "weight_g": 481, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-02872/02820 is the NTN 4T catalogue entry for a 28.575×73.025×22.225 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 02872/02820 without it. Speed planning uses both catalogue columns: grease 5,300 r/min is the mechanical ceiling for 4T-02872/02820, oil 7,000 r/min with circulating oil — a 1,700 r/min margin at this size. Cup-side note for 02820: within the pure-numeric inch family tables the 02872 cone is listed against several cup options, and it is the cup that fixes the 73.025 mm OD and the 22.225 mm assembled width — quote the full 02872/02820 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-02872/02820 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 28.575 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-02872/02820.", "The pure-numeric inch family at 28.575 mm bore (73.025×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 02872/02820 reference at purchase.", "Do not confuse T (22.225 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Do not confuse T (22.225 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Inch and metric bores collide on paper — 28.575 mm is 1.125 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 62.5/68 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-02872/02820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-02872/02820?", "a": "4T-02872/02820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 28.575 mm bore (1.125 in), 73.025 mm outside diameter and 22.225 mm assembled width T (2.875 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 62.5 kN, C0 68 kN, grease limiting speed 5,300 r/min, oil speed 7,000 r/min, mass about 481 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-02872/02820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 02872 cone or the 02820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 62.5/68 kN ratings change with the cup." }, { "q": "What is the difference between 4T-02872/02820 and a metric ISO 355 tapered bearing?", "a": "4T-02872/02820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 28.575×73.025×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-02872/02820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 02872/02820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-02872/02820 list two speeds, 5,300 and 7,000 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-02872/02820 at 7,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "02872", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-02872-02820", "02872-02820", "4T-02872-02820" ], "locale_variants": {} }, { "sku": "L45449-L45410", "brand": "NTN", "manufacturer_designation": "NTN 4T-L45449/L45410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 29, "D_mm": 50.292, "B_mm": 14.224, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 31, "static_load_kN": 35.5, "limiting_speed_rpm": 7200, "max_rpm": 7200, "speed_oil_rpm": 9600, "weight_g": 113, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-L45449/L45410 at 29 mm bore (1.142 in), 50.292 mm cup OD and 14.224 mm assembled T, with a grease limiting speed of 7,200 r/min and an oil ceiling of 9,600 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote L45449/L45410 without it. The 10.6 mm radial section over the 29 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-L45449/L45410: press the L45410 cup square into the 50.292 mm seat first, then bring the L45449 cone (on its 29 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-L45449/L45410 run near 7,200 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 29 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-L45449/L45410.", "The light L family at 29 mm bore (50.292×14.224 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L45449/L45410 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 14.224 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 14.224 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 29 mm is 1.142 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 31/35.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L45449/L45410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L45449/L45410?", "a": "4T-L45449/L45410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 29 mm bore (1.142 in), 50.292 mm outside diameter and 14.224 mm assembled width T (1.98 × 0.56 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 31 kN, C0 35.5 kN, grease limiting speed 7,200 r/min, oil speed 9,600 r/min, mass about 113 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L45449/L45410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L45449 cone or the L45410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 31/35.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L45449/L45410 and a metric ISO 355 tapered bearing?", "a": "4T-L45449/L45410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 29×50.292×14.224 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L45449/L45410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L45449/L45410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L45449/L45410 list two speeds, 7,200 and 9,600 r/min?", "a": "The lower figure, 7,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L45449/L45410 at 9,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L45449-410", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l45449-l45410", "l45449-l45410", "L45449-L45410", "4T-L45449-L45410" ], "locale_variants": {} }, { "sku": "2690-2631", "brand": "NTN", "manufacturer_designation": "NTN 4T-2690/2631", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 29.367, "D_mm": 66.421, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 71.5, "static_load_kN": 72.5, "limiting_speed_rpm": 6200, "max_rpm": 6200, "speed_oil_rpm": 8200, "weight_g": 407, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-2690/2631 at 29.367 mm bore (1.156 in), 66.421 mm cup OD and 23.812 mm assembled T, with a grease limiting speed of 6,200 r/min and an oil ceiling of 8,200 r/min. Reading the designation: 4T-2690/2631 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Contact-angle geometry of the pure-numeric inch family gives 4T-2690/2631 its radial/axial load split — at 71.5/72.5 kN the static rating is about 1.01× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 2631: within the pure-numeric inch family tables the 2690 cone is listed against several cup options, and it is the cup that fixes the 66.421 mm OD and the 23.812 mm assembled width — quote the full 2690/2631 pair, never the cone alone. Running clearance of 4T-2690/2631 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 29.367 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2690/2631.", "The pure-numeric inch family at 29.367 mm bore (66.421×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2690/2631 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 2690 and 2631; use undercut shoulders so the rings seat on the face, not on a radius.", "Replacing one half of an adjusted pair without resetting end play negates the 23.812 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-2690/2631 sets have no seals: a hub or gearbox needs external sealing or the 6,200 r/min grease figure is meaningless once water reaches the cone rib.", "The 71.5/72.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2690/2631; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2690/2631?", "a": "4T-2690/2631 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 29.367 mm bore (1.156 in), 66.421 mm outside diameter and 23.812 mm assembled width T (2.615 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 71.5 kN, C0 72.5 kN, grease limiting speed 6,200 r/min, oil speed 8,200 r/min, mass about 407 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2690/2631 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2690 cone or the 2631 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 71.5/72.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2690/2631 and a metric ISO 355 tapered bearing?", "a": "4T-2690/2631 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 29.367×66.421×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2690/2631 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2690/2631 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2690/2631 list two speeds, 6,200 and 8,200 r/min?", "a": "The lower figure, 6,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2690/2631 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2690", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2690-2631", "2690-2631", "4T-2690-2631" ], "locale_variants": {} }, { "sku": "15117-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15117/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 29.987, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-15117/15245 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-15117/15245 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 19.05 mm T of each 4T-15117/15245 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 15245: within the pure-numeric inch family tables the 15117 cone is listed against several cup options, and it is the cup that fixes the 62 mm OD and the 19.05 mm assembled width — quote the full 15117/15245 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 29.987 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 29.987 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15117/15245.", "The pure-numeric inch family at 29.987 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15117/15245 reference at purchase.", "Inch and metric bores collide on paper — 29.987 mm is 1.181 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Quote the full 15117/15245 pair at ordering: the 15117 cone also ships against sibling cups, and a cup from another reference changes the 19.05 mm assembled width and the rating.", "Inch and metric bores collide on paper — 29.987 mm is 1.181 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15117/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15117/15245?", "a": "4T-15117/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 29.987 mm bore (1.181 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 270 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15117/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15117 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15117/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15117/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 29.987×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15117/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15117/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15117/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15117/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15117", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15117-15245", "15117-15245", "4T-15117-15245" ], "locale_variants": {} }, { "sku": "17118-17244", "brand": "NTN", "manufacturer_designation": "NTN 4T-17118/17244", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 29.987, "D_mm": 62, "B_mm": 16.002, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 43, "static_load_kN": 42, "limiting_speed_rpm": 6300, "max_rpm": 6300, "speed_oil_rpm": 8400, "weight_g": 229, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 29.987 mm carrying combined radial and thrust load, NTN lists 4T-17118/17244, a single-row 4T tapered roller set of 43 kN C and 42 kN C0 inside the 62 mm OD cup. Cone and cup of 4T-17118/17244 are separately stocked parts: a worn 17244 cup can be replaced against the existing 17118 cone, provided the new cup carries the identical reference — pairing across references changes the 16.002 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 6,300 r/min is the mechanical ceiling for 4T-17118/17244, oil 8,400 r/min with circulating oil — a 2,100 r/min margin at this size. The printed 43/42 kN ratings belong to the assembled 17118+17244 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-17118/17244 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 29.987 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-17118/17244.", "The pure-numeric inch family at 29.987 mm bore (62×16.002 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 17118/17244 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 17118 and 17244; use undercut shoulders so the rings seat on the face, not on a radius.", "Open 4T-17118/17244 sets have no seals: a hub or gearbox needs external sealing or the 6,300 r/min grease figure is meaningless once water reaches the cone rib.", "Inch and metric bores collide on paper — 29.987 mm is 1.181 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 43/42 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-17118/17244; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-17118/17244?", "a": "4T-17118/17244 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 29.987 mm bore (1.181 in), 62 mm outside diameter and 16.002 mm assembled width T (2.441 × 0.63 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 43 kN, C0 42 kN, grease limiting speed 6,300 r/min, oil speed 8,400 r/min, mass about 229 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-17118/17244 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 17118 cone or the 17244 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 43/42 kN ratings change with the cup." }, { "q": "What is the difference between 4T-17118/17244 and a metric ISO 355 tapered bearing?", "a": "4T-17118/17244 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 29.987×62×16.002 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-17118/17244 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 17118/17244 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-17118/17244 list two speeds, 6,300 and 8,400 r/min?", "a": "The lower figure, 6,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-17118/17244 at 8,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "17118", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-17118-17244", "17118-17244", "4T-17118-17244" ], "locale_variants": {} }, { "sku": "14117A-14276", "brand": "NTN", "manufacturer_designation": "NTN 4T-14117A/14276", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 69.012, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53.5, "static_load_kN": 58, "limiting_speed_rpm": 5600, "max_rpm": 5600, "speed_oil_rpm": 7400, "weight_g": 370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-14117A/14276 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 14117A and cup 14276 delivered as a matched, separable pair of 30 mm bore and 69.012 mm outside diameter. Reading the designation: 4T-14117A/14276 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 30×69.012×19.845 mm converts to 1.181 × 2.717 × 0.781 in; the ABMA envelope swaps with like-numbered inch parts but the 53.5/58 kN ratings are NTN-specific. Cup-side note for 14276: within the pure-numeric inch family tables the 14117A cone is listed against several cup options, and it is the cup that fixes the 69.012 mm OD and the 19.845 mm assembled width — quote the full 14117A/14276 pair, never the cone alone. Mount the 30 mm cone with an induction heater (max 120 °C) and press the 69.012 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 30 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-14117A/14276.", "The pure-numeric inch family at 30 mm bore (69.012×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 14117A/14276 reference at purchase.", "Open 4T-14117A/14276 sets have no seals: a hub or gearbox needs external sealing or the 5,600 r/min grease figure is meaningless once water reaches the cone rib.", "Grease packs must leave free volume inside the 19.845 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,400 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 30 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 53.5/58 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-14117A/14276; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-14117A/14276?", "a": "4T-14117A/14276 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30 mm bore (1.181 in), 69.012 mm outside diameter and 19.845 mm assembled width T (2.717 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53.5 kN, C0 58 kN, grease limiting speed 5,600 r/min, oil speed 7,400 r/min, mass about 370 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-14117A/14276 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 14117A cone or the 14276 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53.5/58 kN ratings change with the cup." }, { "q": "What is the difference between 4T-14117A/14276 and a metric ISO 355 tapered bearing?", "a": "4T-14117A/14276 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30×69.012×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-14117A/14276 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 14117A/14276 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-14117A/14276 list two speeds, 5,600 and 7,400 r/min?", "a": "The lower figure, 5,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-14117A/14276 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "14117A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "14117a-14276", "4t-14117a-14276", "14117A-14276", "4T-14117A-14276" ], "locale_variants": {} }, { "sku": "JHM88540-JHM88513", "brand": "NTN", "manufacturer_designation": "NTN 4T-JHM88540/JHM88513", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30, "D_mm": 72, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 80, "static_load_kN": 97, "limiting_speed_rpm": 5400, "max_rpm": 5400, "speed_oil_rpm": 7100, "weight_g": 620, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JHM88540/JHM88513 is the NTN 4T catalogue entry for a 30×72×29.37 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote JHM88540/JHM88513 without it. Catalogue mass of the 4T-JHM88540/JHM88513 cone-plus-cup set is 620 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-JHM88540/JHM88513: press the JHM88513 cup square into the 72 mm seat first, then bring the JHM88540 cone (on its 30 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-JHM88540/JHM88513, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 30 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-JHM88540/JHM88513.", "The J-prefixed JHM88540 code belongs to a metric-envelope inch family: its 30 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Quote the full JHM88540/JHM88513 pair at ordering: the JHM88540 cone also ships against sibling cups, and a cup from another reference changes the 29.37 mm assembled width and the rating.", "Inch and metric bores collide on paper — 30 mm is 1.181 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Shaft and housing fillets must clear the ring chamfers of JHM88540 and JHM88513; use undercut shoulders so the rings seat on the face, not on a radius.", "The 80/97 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JHM88540/JHM88513; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JHM88540/JHM88513?", "a": "4T-JHM88540/JHM88513 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30 mm bore (1.181 in), 72 mm outside diameter and 29.37 mm assembled width T (2.835 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 80 kN, C0 97 kN, grease limiting speed 5,400 r/min, oil speed 7,100 r/min, mass about 620 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JHM88540/JHM88513 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JHM88540 cone or the JHM88513 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 80/97 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JHM88540/JHM88513 and a metric ISO 355 tapered bearing?", "a": "4T-JHM88540/JHM88513 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30×72×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JHM88540/JHM88513 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JHM88540/JHM88513 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JHM88540/JHM88513 list two speeds, 5,400 and 7,100 r/min?", "a": "The lower figure, 5,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JHM88540/JHM88513 at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JHM88540", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jhm88540-jhm88513", "4t-jhm88540-jhm88513", "jhm88540-jhm88513", "JHM88540-JHM88513", "4T-JHM88540-JHM88513" ], "locale_variants": {} }, { "sku": "15116-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15116/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30.112, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 30.112 mm carrying combined radial and thrust load, NTN lists 4T-15116/15245, a single-row 4T tapered roller set of 52 kN C and 54 kN C0 inside the 62 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 15116 sits in the pure-numeric inch family. Imperial cross-check for the drawing: 30.112×62×19.05 mm converts to 1.186 × 2.441 × 0.75 in; the ABMA envelope swaps with like-numbered inch parts but the 52/54 kN ratings are NTN-specific. Housing fitment sequence for 4T-15116/15245: press the 15245 cup square into the 62 mm seat first, then bring the 15116 cone (on its 30.112 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-15116/15245 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 30.112 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15116/15245.", "The pure-numeric inch family at 30.112 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15116/15245 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 19.05 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 30.112 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (19.05 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15116/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15116/15245?", "a": "4T-15116/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30.112 mm bore (1.186 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 270 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15116/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15116 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15116/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15116/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30.112×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15116/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15116/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15116/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15116/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15116", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15116-15245", "15116-15245", "4T-15116-15245" ], "locale_variants": {} }, { "sku": "17119-17244", "brand": "NTN", "manufacturer_designation": "NTN 4T-17119/17244", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30.162, "D_mm": 62, "B_mm": 16.002, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 43, "static_load_kN": 42, "limiting_speed_rpm": 6300, "max_rpm": 6300, "speed_oil_rpm": 8400, "weight_g": 228, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-17119/17244 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 17119 sits in the pure-numeric inch family. Catalogue mass of the 4T-17119/17244 cone-plus-cup set is 228 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-17119/17244: press the 17244 cup square into the 62 mm seat first, then bring the 17119 cone (on its 30.162 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 30.162 mm cone with an induction heater (max 120 °C) and press the 62 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 30.162 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-17119/17244.", "The pure-numeric inch family at 30.162 mm bore (62×16.002 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 17119/17244 reference at purchase.", "Do not confuse T (16.002 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Do not confuse T (16.002 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Shaft and housing fillets must clear the ring chamfers of 17119 and 17244; use undercut shoulders so the rings seat on the face, not on a radius.", "The 43/42 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-17119/17244; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-17119/17244?", "a": "4T-17119/17244 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30.162 mm bore (1.187 in), 62 mm outside diameter and 16.002 mm assembled width T (2.441 × 0.63 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 43 kN, C0 42 kN, grease limiting speed 6,300 r/min, oil speed 8,400 r/min, mass about 228 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-17119/17244 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 17119 cone or the 17244 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 43/42 kN ratings change with the cup." }, { "q": "What is the difference between 4T-17119/17244 and a metric ISO 355 tapered bearing?", "a": "4T-17119/17244 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30.162×62×16.002 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-17119/17244 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 17119/17244 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-17119/17244 list two speeds, 6,300 and 8,400 r/min?", "a": "The lower figure, 6,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-17119/17244 at 8,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "17119", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-17119-17244", "17119-17244", "4T-17119-17244" ], "locale_variants": {} }, { "sku": "M86649-M86610", "brand": "NTN", "manufacturer_designation": "NTN 4T-M86649/M86610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30.162, "D_mm": 64.292, "B_mm": 21.433, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 57.5, "static_load_kN": 64.5, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8100, "weight_g": 336, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-M86649/M86610 denotes the medium M family of NTN inch tapered roller bearings — cone M86649 and cup M86610 delivered as a matched, separable pair of 30.162 mm bore and 64.292 mm outside diameter. Reading the designation: 4T-M86649/M86610 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the medium M family lettering ties the pair to its boundary plan. Selection: C 57.5 kN against C0 64.5 kN gives a C0/C ratio of 1.12 for the 30.162 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-M86649/M86610: press the M86610 cup square into the 64.292 mm seat first, then bring the M86649 cone (on its 30.162 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-M86649/M86610 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 30.162 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-M86649/M86610.", "The medium M family at 30.162 mm bore (64.292×21.433 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full M86649/M86610 reference at purchase.", "An unloaded 4T-M86649/M86610 near 6,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 21.433 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 30.162 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 57.5/64.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-M86649/M86610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-M86649/M86610?", "a": "4T-M86649/M86610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30.162 mm bore (1.187 in), 64.292 mm outside diameter and 21.433 mm assembled width T (2.531 × 0.844 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 57.5 kN, C0 64.5 kN, grease limiting speed 6,100 r/min, oil speed 8,100 r/min, mass about 336 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-M86649/M86610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the M86649 cone or the M86610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 57.5/64.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-M86649/M86610 and a metric ISO 355 tapered bearing?", "a": "4T-M86649/M86610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30.162×64.292×21.433 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-M86649/M86610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare M86649/M86610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-M86649/M86610 list two speeds, 6,100 and 8,100 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-M86649/M86610 at 8,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "M86649-610", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-m86649-m86610", "m86649-m86610", "M86649-M86610", "4T-M86649-M86610" ], "locale_variants": {} }, { "sku": "2558-2523", "brand": "NTN", "manufacturer_designation": "NTN 4T-2558/2523", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30.162, "D_mm": 69.85, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 76.5, "static_load_kN": 81.5, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 467, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-2558/2523 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 30.162×69.85×23.812 mm (assembled width T), for a shaft of about 30.162 mm (1.187 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 2558 identifies the cone of 30.162 mm (1.187 in) bore by catalogue lookup, and 2523 fixes the 69.85 mm OD. Contact-angle geometry of the pure-numeric inch family gives 4T-2558/2523 its radial/axial load split — at 76.5/81.5 kN the static rating is about 1.07× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-2558/2523: press the 2523 cup square into the 69.85 mm seat first, then bring the 2558 cone (on its 30.162 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-2558/2523 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 30.162 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2558/2523.", "The pure-numeric inch family at 30.162 mm bore (69.85×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2558/2523 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 2558 and 2523; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-2558/2523 near 5,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of 2558 and 2523; use undercut shoulders so the rings seat on the face, not on a radius.", "The 76.5/81.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2558/2523; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2558/2523?", "a": "4T-2558/2523 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30.162 mm bore (1.187 in), 69.85 mm outside diameter and 23.812 mm assembled width T (2.75 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 76.5 kN, C0 81.5 kN, grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 467 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2558/2523 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2558 cone or the 2523 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 76.5/81.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2558/2523 and a metric ISO 355 tapered bearing?", "a": "4T-2558/2523 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30.162×69.85×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2558/2523 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2558/2523 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2558/2523 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2558/2523 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2558", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2558-2523", "2558-2523", "4T-2558-2523" ], "locale_variants": {} }, { "sku": "3187-3120", "brand": "NTN", "manufacturer_designation": "NTN 4T-3187/3120", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30.162, "D_mm": 72.626, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 93.5, "static_load_kN": 98, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7300, "weight_g": 621, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3187/3120 is the NTN 4T catalogue entry for a 30.162×72.626×30.162 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 3187/3120 without it. The 3.1 kN of dynamic capacity per millimetre of bore summarises the 93.5 kN rating over the 30.162 mm bore — sanity-check any interchange candidate against this ratio and the 30.162 mm T. Housing fitment sequence for 4T-3187/3120: press the 3120 cup square into the 72.626 mm seat first, then bring the 3187 cone (on its 30.162 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-3187/3120 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 30.162 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3187/3120.", "The pure-numeric inch family at 30.162 mm bore (72.626×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3187/3120 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 30.162 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of 3187 and 3120; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 30.162 mm is 1.187 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 93.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3187/3120; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3187/3120?", "a": "4T-3187/3120 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30.162 mm bore (1.187 in), 72.626 mm outside diameter and 30.162 mm assembled width T (2.859 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 93.5 kN, C0 98 kN, grease limiting speed 5,500 r/min, oil speed 7,300 r/min, mass about 621 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3187/3120 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3187 cone or the 3120 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 93.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3187/3120 and a metric ISO 355 tapered bearing?", "a": "4T-3187/3120 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30.162×72.626×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3187/3120 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3187/3120 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3187/3120 list two speeds, 5,500 and 7,300 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3187/3120 at 7,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3187", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3187-3120", "3187-3120", "4T-3187-3120" ], "locale_variants": {} }, { "sku": "15118-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15118/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30.213, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 266, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-15118/15245 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 30.213×62×19.05 mm (assembled width T), for a shaft of about 30.213 mm (1.189 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 15118/15245 without it. Speed planning uses both catalogue columns: grease 6,100 r/min is the mechanical ceiling for 4T-15118/15245, oil 8,200 r/min with circulating oil — a 2,100 r/min margin at this size. The printed 52/54 kN ratings belong to the assembled 15118+15245 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-15118/15245, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 30.213 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15118/15245.", "The pure-numeric inch family at 30.213 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15118/15245 reference at purchase.", "An unloaded 4T-15118/15245 near 6,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 30.213 mm is 1.189 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Shaft and housing fillets must clear the ring chamfers of 15118 and 15245; use undercut shoulders so the rings seat on the face, not on a radius.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15118/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15118/15245?", "a": "4T-15118/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30.213 mm bore (1.189 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 266 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15118/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15118 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15118/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15118/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30.213×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15118/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15118/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15118/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15118/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15118", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15118-15245", "15118-15245", "4T-15118-15245" ], "locale_variants": {} }, { "sku": "15119-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15119/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30.213, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 269, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-15119/15245 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 15119 identifies the cone of 30.213 mm (1.189 in) bore by catalogue lookup, and 15245 fixes the 62 mm OD. The 15.9 mm radial section over the 30.213 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-15119/15245: press the 15245 cup square into the 62 mm seat first, then bring the 15119 cone (on its 30.213 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-15119/15245 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 30.213 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15119/15245.", "The pure-numeric inch family at 30.213 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15119/15245 reference at purchase.", "Never drive the 62 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 4T-15119/15245 sets have no seals: a hub or gearbox needs external sealing or the 6,100 r/min grease figure is meaningless once water reaches the cone rib.", "Grease packs must leave free volume inside the 19.05 mm-wide set; over-greasing a pair churning near the oil-band speed of 8,200 r/min raises temperature and destroys the setting.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15119/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15119/15245?", "a": "4T-15119/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30.213 mm bore (1.189 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 269 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15119/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15119 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15119/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15119/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30.213×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15119/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15119/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15119/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15119/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15119", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15119-15245", "15119-15245", "4T-15119-15245" ], "locale_variants": {} }, { "sku": "15120-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15120/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30.213, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 269, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 30.213 mm carrying combined radial and thrust load, NTN lists 4T-15120/15245, a single-row 4T tapered roller set of 52 kN C and 54 kN C0 inside the 62 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 15120/15245 without it. The 15.9 mm radial section over the 30.213 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-15120/15245: press the 15245 cup square into the 62 mm seat first, then bring the 15120 cone (on its 30.213 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 30.213 mm cone with an induction heater (max 120 °C) and press the 62 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 30.213 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15120/15245.", "The pure-numeric inch family at 30.213 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15120/15245 reference at purchase.", "Do not confuse T (19.05 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Never drive the 62 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 4T-15120/15245 sets have no seals: a hub or gearbox needs external sealing or the 6,100 r/min grease figure is meaningless once water reaches the cone rib.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15120/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15120/15245?", "a": "4T-15120/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30.213 mm bore (1.189 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 269 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15120/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15120 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15120/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15120/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30.213×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15120/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15120/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15120/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15120/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15120", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15120-15245", "15120-15245", "4T-15120-15245" ], "locale_variants": {} }, { "sku": "14116-14274", "brand": "NTN", "manufacturer_designation": "NTN 4T-14116/14274", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30.226, "D_mm": 69.012, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53.5, "static_load_kN": 58, "limiting_speed_rpm": 5600, "max_rpm": 5600, "speed_oil_rpm": 7400, "weight_g": 369, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-14116/14274 at 30.226 mm bore (1.19 in), 69.012 mm cup OD and 19.845 mm assembled T, with a grease limiting speed of 5,600 r/min and an oil ceiling of 7,400 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 14116/14274 without it. Catalogue mass of the 4T-14116/14274 cone-plus-cup set is 369 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 14274: within the pure-numeric inch family tables the 14116 cone is listed against several cup options, and it is the cup that fixes the 69.012 mm OD and the 19.845 mm assembled width — quote the full 14116/14274 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-14116/14274, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 30.226 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-14116/14274.", "The pure-numeric inch family at 30.226 mm bore (69.012×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 14116/14274 reference at purchase.", "Do not confuse T (19.845 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 30.226 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Open 4T-14116/14274 sets have no seals: a hub or gearbox needs external sealing or the 5,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 53.5/58 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-14116/14274; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-14116/14274?", "a": "4T-14116/14274 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30.226 mm bore (1.19 in), 69.012 mm outside diameter and 19.845 mm assembled width T (2.717 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53.5 kN, C0 58 kN, grease limiting speed 5,600 r/min, oil speed 7,400 r/min, mass about 369 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-14116/14274 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 14116 cone or the 14274 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53.5/58 kN ratings change with the cup." }, { "q": "What is the difference between 4T-14116/14274 and a metric ISO 355 tapered bearing?", "a": "4T-14116/14274 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30.226×69.012×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-14116/14274 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 14116/14274 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-14116/14274 list two speeds, 5,600 and 7,400 r/min?", "a": "The lower figure, 5,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-14116/14274 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "14116-14276", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-14116 paired with a different cup (14276): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-14116-14274", "14116-14274", "4T-14116-14274" ], "locale_variants": {} }, { "sku": "14116-14276", "brand": "NTN", "manufacturer_designation": "NTN 4T-14116/14276", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 30.226, "D_mm": 69.012, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53.5, "static_load_kN": 58, "limiting_speed_rpm": 5600, "max_rpm": 5600, "speed_oil_rpm": 7400, "weight_g": 371, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-14116/14276 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 14116 sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 19.845 mm T of each 4T-14116/14276 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 14276: within the pure-numeric inch family tables the 14116 cone is listed against several cup options, and it is the cup that fixes the 69.012 mm OD and the 19.845 mm assembled width — quote the full 14116/14276 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-14116/14276 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 30.226 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-14116/14276.", "The pure-numeric inch family at 30.226 mm bore (69.012×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 14116/14276 reference at purchase.", "Grease packs must leave free volume inside the 19.845 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,400 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 30.226 mm is 1.19 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Replacing one half of an adjusted pair without resetting end play negates the 19.845 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 53.5/58 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-14116/14276; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-14116/14276?", "a": "4T-14116/14276 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 30.226 mm bore (1.19 in), 69.012 mm outside diameter and 19.845 mm assembled width T (2.717 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53.5 kN, C0 58 kN, grease limiting speed 5,600 r/min, oil speed 7,400 r/min, mass about 371 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-14116/14276 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 14116 cone or the 14276 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53.5/58 kN ratings change with the cup." }, { "q": "What is the difference between 4T-14116/14276 and a metric ISO 355 tapered bearing?", "a": "4T-14116/14276 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 30.226×69.012×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-14116/14276 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 14116/14276 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-14116/14276 list two speeds, 5,600 and 7,400 r/min?", "a": "The lower figure, 5,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-14116/14276 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "14116-14274", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-14116 paired with a different cup (14274): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-14116-14276", "14116-14276", "4T-14116-14276" ], "locale_variants": {} }, { "sku": "LM67048-LM67010", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM67048/LM67010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 59.131, "B_mm": 15.875, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 38.5, "static_load_kN": 41, "limiting_speed_rpm": 6300, "max_rpm": 6300, "speed_oil_rpm": 8400, "weight_g": 183, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-LM67048/LM67010 denotes the light-medium LM family of NTN inch tapered roller bearings — cone LM67048 and cup LM67010 delivered as a matched, separable pair of 31.75 mm bore and 59.131 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: LM67048 identifies the cone of 31.75 mm (1.25 in) bore by catalogue lookup, and LM67010 fixes the 59.131 mm OD. Selection: C 38.5 kN against C0 41 kN gives a C0/C ratio of 1.06 for the 31.75 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-LM67048/LM67010: press the LM67010 cup square into the 59.131 mm seat first, then bring the LM67048 cone (on its 31.75 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Contact-pattern check with marking blue: a pattern biased to one roller end means the 31.75 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM67048/LM67010.", "The light-medium LM family at 31.75 mm bore (59.131×15.875 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM67048/LM67010 reference at purchase.", "Inch and metric bores collide on paper — 31.75 mm is 1.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Quote the full LM67048/LM67010 pair at ordering: the LM67048 cone also ships against sibling cups, and a cup from another reference changes the 15.875 mm assembled width and the rating.", "Do not confuse T (15.875 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 38.5/41 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM67048/LM67010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM67048/LM67010?", "a": "4T-LM67048/LM67010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 59.131 mm outside diameter and 15.875 mm assembled width T (2.328 × 0.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 38.5 kN, C0 41 kN, grease limiting speed 6,300 r/min, oil speed 8,400 r/min, mass about 183 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM67048/LM67010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM67048 cone or the LM67010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 38.5/41 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM67048/LM67010 and a metric ISO 355 tapered bearing?", "a": "4T-LM67048/LM67010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×59.131×15.875 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM67048/LM67010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM67048/LM67010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM67048/LM67010 list two speeds, 6,300 and 8,400 r/min?", "a": "The lower figure, 6,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM67048/LM67010 at 8,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM67048-010", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75×59.131×15.875 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm67048-lm67010", "lm67048-lm67010", "LM67048-LM67010", "4T-LM67048-LM67010" ], "locale_variants": {} }, { "sku": "15123-15245-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-15123/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 62, "B_mm": 18.161, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 249, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-15123/15245 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 15123 identifies the cone of 31.75 mm (1.25 in) bore by catalogue lookup, and 15245 fixes the 62 mm OD. Catalogue mass of the 4T-15123/15245 cone-plus-cup set is 249 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 15245: within the pure-numeric inch family tables the 15123 cone is listed against several cup options, and it is the cup that fixes the 62 mm OD and the 18.161 mm assembled width — quote the full 15123/15245 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-15123/15245, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15123/15245.", "The pure-numeric inch family at 31.75 mm bore (62×18.161 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15123/15245 reference at purchase.", "ABMA makes the 31.75×62 mm envelope interchangeable, not the ratings: NTN prints 52/54 kN for this execution and another make of the same number can differ in roller complement.", "Grease packs must leave free volume inside the 18.161 mm-wide set; over-greasing a pair churning near the oil-band speed of 8,200 r/min raises temperature and destroys the setting.", "Grease packs must leave free volume inside the 18.161 mm-wide set; over-greasing a pair churning near the oil-band speed of 8,200 r/min raises temperature and destroys the setting.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15123/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15123/15245?", "a": "4T-15123/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 62 mm outside diameter and 18.161 mm assembled width T (2.441 × 0.715 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 249 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15123/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15123 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15123/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15123/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×62×18.161 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15123/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15123/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15123/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15123/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15123-15243", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75×62×18.161 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "15123-15245", "equiv_brand": "SKF", "level": "partial", "note": "Same 31.75×62×18.161 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15123-15245", "15123-15245", "4T-15123-15245", "15123-15245-NTN" ], "locale_variants": {} }, { "sku": "15125-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15125/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 254, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-15125/15245 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 15125 and cup 15245 delivered as a matched, separable pair of 31.75 mm bore and 62 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 15125/15245 without it. The 15.1 mm radial section over the 31.75 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 52/54 kN ratings belong to the assembled 15125+15245 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-15125/15245 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15125/15245.", "The pure-numeric inch family at 31.75 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15125/15245 reference at purchase.", "Inch and metric bores collide on paper — 31.75 mm is 1.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 19.05 mm-wide set; over-greasing a pair churning near the oil-band speed of 8,200 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 31.75 mm is 1.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15125/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15125/15245?", "a": "4T-15125/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 254 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15125/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15125 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15125/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15125/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15125/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15125/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15125/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15125/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15125", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=177", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15125-15245", "15125-15245", "4T-15125-15245" ], "locale_variants": {} }, { "sku": "15126-15245", "brand": "NTN", "manufacturer_designation": "NTN 4T-15126/15245", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 62, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 52, "static_load_kN": 54, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8200, "weight_g": 257, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-15126/15245 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 31.75×62×19.05 mm (assembled width T), for a shaft of about 31.75 mm (1.25 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 15126 identifies the cone of 31.75 mm (1.25 in) bore by catalogue lookup, and 15245 fixes the 62 mm OD. Grease relubrication at the 6,100 r/min limiting speed targets the cone-rib contact; sustaining 8,200 r/min needs an oil supply directed at the large roller ends. Cup-side note for 15245: within the pure-numeric inch family tables the 15126 cone is listed against several cup options, and it is the cup that fixes the 62 mm OD and the 19.05 mm assembled width — quote the full 15126/15245 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-15126/15245 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-15126/15245.", "The pure-numeric inch family at 31.75 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15126/15245 reference at purchase.", "An unloaded 4T-15126/15245 near 6,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of 15126 and 15245; use undercut shoulders so the rings seat on the face, not on a radius.", "ABMA makes the 31.75×62 mm envelope interchangeable, not the ratings: NTN prints 52/54 kN for this execution and another make of the same number can differ in roller complement.", "The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15126/15245; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-15126/15245?", "a": "4T-15126/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 257 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-15126/15245 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 15126 cone or the 15245 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 52/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-15126/15245 and a metric ISO 355 tapered bearing?", "a": "4T-15126/15245 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×62×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-15126/15245 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 15126/15245 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-15126/15245 list two speeds, 6,100 and 8,200 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-15126/15245 at 8,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "15126", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-15126-15245", "15126-15245", "4T-15126-15245" ], "locale_variants": {} }, { "sku": "2580-2520", "brand": "NTN", "manufacturer_designation": "NTN 4T-2580/2520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 66.421, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 76.5, "static_load_kN": 81.5, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-2580/2520 at 31.75 mm bore (1.25 in), 66.421 mm cup OD and 25.4 mm assembled T, with a grease limiting speed of 5,700 r/min and an oil ceiling of 7,600 r/min. Cone and cup of 4T-2580/2520 are separately stocked parts: a worn 2520 cup can be replaced against the existing 2580 cone, provided the new cup carries the identical reference — pairing across references changes the 25.4 mm assembled width and the rating. Imperial cross-check for the drawing: 31.75×66.421×25.4 mm converts to 1.25 × 2.615 × 1 in; the ABMA envelope swaps with like-numbered inch parts but the 76.5/81.5 kN ratings are NTN-specific. Housing fitment sequence for 4T-2580/2520: press the 2520 cup square into the 66.421 mm seat first, then bring the 2580 cone (on its 31.75 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 31.75 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2580/2520.", "The pure-numeric inch family at 31.75 mm bore (66.421×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2580/2520 reference at purchase.", "Do not confuse T (25.4 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-2580/2520 sets have no seals: a hub or gearbox needs external sealing or the 5,700 r/min grease figure is meaningless once water reaches the cone rib.", "Fit selection follows the rotating ring: a rotating cone on a 31.75 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 76.5/81.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2580/2520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2580/2520?", "a": "4T-2580/2520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 66.421 mm outside diameter and 25.4 mm assembled width T (2.615 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 76.5 kN, C0 81.5 kN, grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 410 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2580/2520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2580 cone or the 2520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 76.5/81.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2580/2520 and a metric ISO 355 tapered bearing?", "a": "4T-2580/2520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×66.421×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2580/2520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2580/2520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2580/2520 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2580/2520 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2580-2523", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-2580 paired with a different cup (2523): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2580-2520", "2580-2520", "4T-2580-2520" ], "locale_variants": {} }, { "sku": "02475-02420", "brand": "NTN", "manufacturer_designation": "NTN 4T-02475/02420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 68.262, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 63, "static_load_kN": 67, "limiting_speed_rpm": 5800, "max_rpm": 5800, "speed_oil_rpm": 7700, "weight_g": 382, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-02475/02420 at 31.75 mm bore (1.25 in), 68.262 mm cup OD and 22.225 mm assembled T, with a grease limiting speed of 5,800 r/min and an oil ceiling of 7,700 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 02475 identifies the cone of 31.75 mm (1.25 in) bore by catalogue lookup, and 02420 fixes the 68.262 mm OD. Catalogue mass of the 4T-02475/02420 cone-plus-cup set is 382 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-02475/02420: press the 02420 cup square into the 68.262 mm seat first, then bring the 02475 cone (on its 31.75 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-02475/02420 run near 5,800 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-02475/02420.", "The pure-numeric inch family at 31.75 mm bore (68.262×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 02475/02420 reference at purchase.", "Never drive the 68.262 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Shaft and housing fillets must clear the ring chamfers of 02475 and 02420; use undercut shoulders so the rings seat on the face, not on a radius.", "Fit selection follows the rotating ring: a rotating cone on a 31.75 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 63/67 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-02475/02420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-02475/02420?", "a": "4T-02475/02420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 68.262 mm outside diameter and 22.225 mm assembled width T (2.687 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 63 kN, C0 67 kN, grease limiting speed 5,800 r/min, oil speed 7,700 r/min, mass about 382 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-02475/02420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 02475 cone or the 02420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 63/67 kN ratings change with the cup." }, { "q": "What is the difference between 4T-02475/02420 and a metric ISO 355 tapered bearing?", "a": "4T-02475/02420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×68.262×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-02475/02420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 02475/02420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-02475/02420 list two speeds, 5,800 and 7,700 r/min?", "a": "The lower figure, 5,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-02475/02420 at 7,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "02475", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-02475-02420", "02475-02420", "4T-02475-02420" ], "locale_variants": {} }, { "sku": "02476-02420", "brand": "NTN", "manufacturer_designation": "NTN 4T-02476/02420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 68.262, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 63, "static_load_kN": 67, "limiting_speed_rpm": 5800, "max_rpm": 5800, "speed_oil_rpm": 7700, "weight_g": 384, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-02476/02420 is the NTN 4T catalogue entry for a 31.75×68.262×22.225 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-02476/02420 are separately stocked parts: a worn 02420 cup can be replaced against the existing 02476 cone, provided the new cup carries the identical reference — pairing across references changes the 22.225 mm assembled width and the rating. The 2.0 kN of dynamic capacity per millimetre of bore summarises the 63 kN rating over the 31.75 mm bore — sanity-check any interchange candidate against this ratio and the 22.225 mm T. The printed 63/67 kN ratings belong to the assembled 02476+02420 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-02476/02420, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-02476/02420.", "The pure-numeric inch family at 31.75 mm bore (68.262×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 02476/02420 reference at purchase.", "Grease packs must leave free volume inside the 22.225 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,700 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 31.75 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Open 4T-02476/02420 sets have no seals: a hub or gearbox needs external sealing or the 5,800 r/min grease figure is meaningless once water reaches the cone rib.", "The 63/67 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-02476/02420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-02476/02420?", "a": "4T-02476/02420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 68.262 mm outside diameter and 22.225 mm assembled width T (2.687 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 63 kN, C0 67 kN, grease limiting speed 5,800 r/min, oil speed 7,700 r/min, mass about 384 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-02476/02420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 02476 cone or the 02420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 63/67 kN ratings change with the cup." }, { "q": "What is the difference between 4T-02476/02420 and a metric ISO 355 tapered bearing?", "a": "4T-02476/02420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×68.262×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-02476/02420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 02476/02420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-02476/02420 list two speeds, 5,800 and 7,700 r/min?", "a": "The lower figure, 5,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-02476/02420 at 7,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "02476", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-02476-02420", "02476-02420", "4T-02476-02420" ], "locale_variants": {} }, { "sku": "14124-14276", "brand": "NTN", "manufacturer_designation": "NTN 4T-14124/14276", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 69.012, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53.5, "static_load_kN": 58, "limiting_speed_rpm": 5600, "max_rpm": 5600, "speed_oil_rpm": 7400, "weight_g": 360, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-14124/14276 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-14124/14276 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 18.6 mm radial section over the 31.75 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-14124/14276: press the 14276 cup square into the 69.012 mm seat first, then bring the 14124 cone (on its 31.75 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 31.75 mm cone with an induction heater (max 120 °C) and press the 69.012 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-14124/14276.", "The pure-numeric inch family at 31.75 mm bore (69.012×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 14124/14276 reference at purchase.", "Grease packs must leave free volume inside the 19.845 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,400 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of 14124 and 14276; use undercut shoulders so the rings seat on the face, not on a radius.", "Never drive the 69.012 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 53.5/58 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-14124/14276; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-14124/14276?", "a": "4T-14124/14276 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 69.012 mm outside diameter and 19.845 mm assembled width T (2.717 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53.5 kN, C0 58 kN, grease limiting speed 5,600 r/min, oil speed 7,400 r/min, mass about 360 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-14124/14276 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 14124 cone or the 14276 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53.5/58 kN ratings change with the cup." }, { "q": "What is the difference between 4T-14124/14276 and a metric ISO 355 tapered bearing?", "a": "4T-14124/14276 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×69.012×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-14124/14276 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 14124/14276 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-14124/14276 list two speeds, 5,600 and 7,400 r/min?", "a": "The lower figure, 5,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-14124/14276 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "14124", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-14124-14276", "14124-14276", "4T-14124-14276" ], "locale_variants": {} }, { "sku": "14125A-14276", "brand": "NTN", "manufacturer_designation": "NTN 4T-14125A/14276", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 69.012, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53.5, "static_load_kN": 58, "limiting_speed_rpm": 5600, "max_rpm": 5600, "speed_oil_rpm": 7400, "weight_g": 357, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-14125A/14276 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-14125A/14276 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Selection: C 53.5 kN against C0 58 kN gives a C0/C ratio of 1.08 for the 31.75 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 53.5/58 kN ratings belong to the assembled 14125A+14276 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-14125A/14276 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-14125A/14276.", "The pure-numeric inch family at 31.75 mm bore (69.012×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 14125A/14276 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 19.845 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 31.75 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 19.845 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,400 r/min raises temperature and destroys the setting.", "The 53.5/58 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-14125A/14276; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-14125A/14276?", "a": "4T-14125A/14276 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 69.012 mm outside diameter and 19.845 mm assembled width T (2.717 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53.5 kN, C0 58 kN, grease limiting speed 5,600 r/min, oil speed 7,400 r/min, mass about 357 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-14125A/14276 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 14125A cone or the 14276 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53.5/58 kN ratings change with the cup." }, { "q": "What is the difference between 4T-14125A/14276 and a metric ISO 355 tapered bearing?", "a": "4T-14125A/14276 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×69.012×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-14125A/14276 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 14125A/14276 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-14125A/14276 list two speeds, 5,600 and 7,400 r/min?", "a": "The lower figure, 5,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-14125A/14276 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "14125A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "14125a-14276", "4t-14125a-14276", "14125A-14276", "4T-14125A-14276" ], "locale_variants": {} }, { "sku": "2580-2523", "brand": "NTN", "manufacturer_designation": "NTN 4T-2580/2523", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 69.85, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 76.5, "static_load_kN": 81.5, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 455, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-2580/2523 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 31.75×69.85×23.812 mm (assembled width T), for a shaft of about 31.75 mm (1.25 in). Reading the designation: 4T-2580/2523 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Selection: C 76.5 kN against C0 81.5 kN gives a C0/C ratio of 1.07 for the 31.75 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-2580/2523: press the 2523 cup square into the 69.85 mm seat first, then bring the 2580 cone (on its 31.75 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-2580/2523; reverse the fit logic when the cup rotates.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2580/2523.", "The pure-numeric inch family at 31.75 mm bore (69.85×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2580/2523 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 31.75 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Replacing one half of an adjusted pair without resetting end play negates the 23.812 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Shaft and housing fillets must clear the ring chamfers of 2580 and 2523; use undercut shoulders so the rings seat on the face, not on a radius.", "The 76.5/81.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2580/2523; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2580/2523?", "a": "4T-2580/2523 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 69.85 mm outside diameter and 23.812 mm assembled width T (2.75 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 76.5 kN, C0 81.5 kN, grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 455 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2580/2523 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2580 cone or the 2523 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 76.5/81.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2580/2523 and a metric ISO 355 tapered bearing?", "a": "4T-2580/2523 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×69.85×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2580/2523 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2580/2523 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2580/2523 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2580/2523 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2580-2520", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-2580 paired with a different cup (2520): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2580-2523", "2580-2523", "4T-2580-2523" ], "locale_variants": {} }, { "sku": "2582-2523", "brand": "NTN", "manufacturer_designation": "NTN 4T-2582/2523", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 69.85, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 76.5, "static_load_kN": 81.5, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 452, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 31.75 mm carrying combined radial and thrust load, NTN lists 4T-2582/2523, a single-row 4T tapered roller set of 76.5 kN C and 81.5 kN C0 inside the 69.85 mm OD cup. Reading the designation: 4T-2582/2523 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Contact-angle geometry of the pure-numeric inch family gives 4T-2582/2523 its radial/axial load split — at 76.5/81.5 kN the static rating is about 1.07× C, typical of inch tapered sets proportioned for combined duty. The printed 76.5/81.5 kN ratings belong to the assembled 2582+2523 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 31.75 mm cone with an induction heater (max 120 °C) and press the 69.85 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2582/2523.", "The pure-numeric inch family at 31.75 mm bore (69.85×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2582/2523 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 23.812 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ABMA makes the 31.75×69.85 mm envelope interchangeable, not the ratings: NTN prints 76.5/81.5 kN for this execution and another make of the same number can differ in roller complement.", "Inch and metric bores collide on paper — 31.75 mm is 1.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 76.5/81.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2582/2523; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2582/2523?", "a": "4T-2582/2523 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 69.85 mm outside diameter and 23.812 mm assembled width T (2.75 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 76.5 kN, C0 81.5 kN, grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 452 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2582/2523 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2582 cone or the 2523 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 76.5/81.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2582/2523 and a metric ISO 355 tapered bearing?", "a": "4T-2582/2523 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×69.85×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2582/2523 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2582/2523 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2582/2523 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2582/2523 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2582", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2582-2523", "2582-2523", "4T-2582-2523" ], "locale_variants": {} }, { "sku": "3188-3120", "brand": "NTN", "manufacturer_designation": "NTN 4T-3188/3120", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 72.626, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 93.5, "static_load_kN": 98, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7300, "weight_g": 606, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3188/3120 is the NTN 4T catalogue entry for a 31.75×72.626×30.162 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Reading the designation: 4T-3188/3120 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 31.75×72.626×30.162 mm converts to 1.25 × 2.859 × 1.187 in; the ABMA envelope swaps with like-numbered inch parts but the 93.5/98 kN ratings are NTN-specific. Housing fitment sequence for 4T-3188/3120: press the 3120 cup square into the 72.626 mm seat first, then bring the 3188 cone (on its 31.75 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Fillet radii must clear the chamfers of the 3188 cone and 3120 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3188/3120.", "The pure-numeric inch family at 31.75 mm bore (72.626×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3188/3120 reference at purchase.", "ABMA makes the 31.75×72.626 mm envelope interchangeable, not the ratings: NTN prints 93.5/98 kN for this execution and another make of the same number can differ in roller complement.", "Never drive the 72.626 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 93.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3188/3120; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3188/3120?", "a": "4T-3188/3120 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 72.626 mm outside diameter and 30.162 mm assembled width T (2.859 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 93.5 kN, C0 98 kN, grease limiting speed 5,500 r/min, oil speed 7,300 r/min, mass about 606 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3188/3120 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3188 cone or the 3120 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 93.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3188/3120 and a metric ISO 355 tapered bearing?", "a": "4T-3188/3120 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×72.626×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3188/3120 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3188/3120 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3188/3120 list two speeds, 5,500 and 7,300 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3188/3120 at 7,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3188", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3188-3120", "3188-3120", "4T-3188-3120" ], "locale_variants": {} }, { "sku": "3193-3120", "brand": "NTN", "manufacturer_designation": "NTN 4T-3193/3120", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 72.626, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 93.5, "static_load_kN": 98, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7300, "weight_g": 605, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3193/3120 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 3193 identifies the cone of 31.75 mm (1.25 in) bore by catalogue lookup, and 3120 fixes the 72.626 mm OD. Speed planning uses both catalogue columns: grease 5,500 r/min is the mechanical ceiling for 4T-3193/3120, oil 7,300 r/min with circulating oil — a 1,800 r/min margin at this size. Housing fitment sequence for 4T-3193/3120: press the 3120 cup square into the 72.626 mm seat first, then bring the 3193 cone (on its 31.75 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-3193/3120 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3193/3120.", "The pure-numeric inch family at 31.75 mm bore (72.626×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3193/3120 reference at purchase.", "Never drive the 72.626 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never drive the 72.626 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 31.75×72.626 mm envelope interchangeable, not the ratings: NTN prints 93.5/98 kN for this execution and another make of the same number can differ in roller complement.", "The 93.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3193/3120; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3193/3120?", "a": "4T-3193/3120 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 72.626 mm outside diameter and 30.162 mm assembled width T (2.859 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 93.5 kN, C0 98 kN, grease limiting speed 5,500 r/min, oil speed 7,300 r/min, mass about 605 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3193/3120 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3193 cone or the 3120 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 93.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3193/3120 and a metric ISO 355 tapered bearing?", "a": "4T-3193/3120 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×72.626×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3193/3120 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3193/3120 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3193/3120 list two speeds, 5,500 and 7,300 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3193/3120 at 7,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3193", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3193-3120", "3193-3120", "4T-3193-3120" ], "locale_variants": {} }, { "sku": "02875-02820", "brand": "NTN", "manufacturer_designation": "NTN 4T-02875/02820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 73.025, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 62.5, "static_load_kN": 68, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7000, "weight_g": 453, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-02875/02820 at 31.75 mm bore (1.25 in), 73.025 mm cup OD and 22.225 mm assembled T, with a grease limiting speed of 5,300 r/min and an oil ceiling of 7,000 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 02875 sits in the pure-numeric inch family. Imperial cross-check for the drawing: 31.75×73.025×22.225 mm converts to 1.25 × 2.875 × 0.875 in; the ABMA envelope swaps with like-numbered inch parts but the 62.5/68 kN ratings are NTN-specific. Cup-side note for 02820: within the pure-numeric inch family tables the 02875 cone is listed against several cup options, and it is the cup that fixes the 73.025 mm OD and the 22.225 mm assembled width — quote the full 02875/02820 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-02875/02820 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-02875/02820.", "The pure-numeric inch family at 31.75 mm bore (73.025×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 02875/02820 reference at purchase.", "Quote the full 02875/02820 pair at ordering: the 02875 cone also ships against sibling cups, and a cup from another reference changes the 22.225 mm assembled width and the rating.", "Grease packs must leave free volume inside the 22.225 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,000 r/min raises temperature and destroys the setting.", "ABMA makes the 31.75×73.025 mm envelope interchangeable, not the ratings: NTN prints 62.5/68 kN for this execution and another make of the same number can differ in roller complement.", "The 62.5/68 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-02875/02820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-02875/02820?", "a": "4T-02875/02820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 73.025 mm outside diameter and 22.225 mm assembled width T (2.875 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 62.5 kN, C0 68 kN, grease limiting speed 5,300 r/min, oil speed 7,000 r/min, mass about 453 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-02875/02820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 02875 cone or the 02820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 62.5/68 kN ratings change with the cup." }, { "q": "What is the difference between 4T-02875/02820 and a metric ISO 355 tapered bearing?", "a": "4T-02875/02820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×73.025×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-02875/02820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 02875/02820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-02875/02820 list two speeds, 5,300 and 7,000 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-02875/02820 at 7,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "02875", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-02875-02820", "02875-02820", "4T-02875-02820" ], "locale_variants": {} }, { "sku": "2879-2820", "brand": "NTN", "manufacturer_designation": "NTN 4T-2879/2820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 73.025, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 69.5, "static_load_kN": 75.5, "limiting_speed_rpm": 5200, "max_rpm": 5200, "speed_oil_rpm": 7000, "weight_g": 466, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.25 in (31.75 mm) shaft position as 4T-2879/2820: cone 2879, cup 2820, profiled rollers and a pressed-steel cage, rated 69.5 kN basic dynamic and 75.5 kN static. Cone and cup of 4T-2879/2820 are separately stocked parts: a worn 2820 cup can be replaced against the existing 2879 cone, provided the new cup carries the identical reference — pairing across references changes the 22.225 mm assembled width and the rating. The 20.6 mm radial section over the 31.75 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 69.5/75.5 kN ratings belong to the assembled 2879+2820 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-2879/2820 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2879/2820.", "The pure-numeric inch family at 31.75 mm bore (73.025×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2879/2820 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 31.75 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Open 4T-2879/2820 sets have no seals: a hub or gearbox needs external sealing or the 5,200 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 31.75×73.025 mm envelope interchangeable, not the ratings: NTN prints 69.5/75.5 kN for this execution and another make of the same number can differ in roller complement.", "The 69.5/75.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2879/2820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2879/2820?", "a": "4T-2879/2820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 73.025 mm outside diameter and 22.225 mm assembled width T (2.875 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 69.5 kN, C0 75.5 kN, grease limiting speed 5,200 r/min, oil speed 7,000 r/min, mass about 466 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2879/2820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2879 cone or the 2820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 69.5/75.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2879/2820 and a metric ISO 355 tapered bearing?", "a": "4T-2879/2820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×73.025×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2879/2820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2879/2820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2879/2820 list two speeds, 5,200 and 7,000 r/min?", "a": "The lower figure, 5,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2879/2820 at 7,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2879", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2879-2820", "2879-2820", "4T-2879-2820" ], "locale_variants": {} }, { "sku": "HM88542-HM88510", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM88542/HM88510", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 73.025, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 80, "static_load_kN": 97, "limiting_speed_rpm": 5400, "max_rpm": 5400, "speed_oil_rpm": 7100, "weight_g": 622, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM88542/HM88510 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HM88542 identifies the cone of 31.75 mm (1.25 in) bore by catalogue lookup, and HM88510 fixes the 73.025 mm OD. Contact-angle geometry of the heavy-medium HM family gives 4T-HM88542/HM88510 its radial/axial load split — at 80/97 kN the static rating is about 1.21× C, typical of inch tapered sets proportioned for combined duty. The printed 80/97 kN ratings belong to the assembled HM88542+HM88510 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 31.75 mm cone with an induction heater (max 120 °C) and press the 73.025 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM88542/HM88510.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 31.75 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Never drive the 73.025 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never drive the 73.025 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 4T-HM88542/HM88510 sets have no seals: a hub or gearbox needs external sealing or the 5,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 80/97 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM88542/HM88510; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM88542/HM88510?", "a": "4T-HM88542/HM88510 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 73.025 mm outside diameter and 29.37 mm assembled width T (2.875 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 80 kN, C0 97 kN, grease limiting speed 5,400 r/min, oil speed 7,100 r/min, mass about 622 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM88542/HM88510 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM88542 cone or the HM88510 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 80/97 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM88542/HM88510 and a metric ISO 355 tapered bearing?", "a": "4T-HM88542/HM88510 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×73.025×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM88542/HM88510 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM88542/HM88510 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM88542/HM88510 list two speeds, 5,400 and 7,100 r/min?", "a": "The lower figure, 5,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM88542/HM88510 at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM88542-510", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "HM88542-HM88512", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-HM88542 paired with a different cup (HM88512): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm88542-hm88510", "hm88542-hm88510", "HM88542-HM88510", "4T-HM88542-HM88510" ], "locale_variants": {} }, { "sku": "HM88542-HM88512", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM88542/HM88512", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 73.812, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 80, "static_load_kN": 97, "limiting_speed_rpm": 5400, "max_rpm": 5400, "speed_oil_rpm": 7100, "weight_g": 638, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-HM88542/HM88512 denotes the heavy-medium HM family of NTN inch tapered roller bearings — cone HM88542 and cup HM88512 delivered as a matched, separable pair of 31.75 mm bore and 73.812 mm outside diameter. Reading the designation: 4T-HM88542/HM88512 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the heavy-medium HM family lettering ties the pair to its boundary plan. Catalogue mass of the 4T-HM88542/HM88512 cone-plus-cup set is 638 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 80/97 kN ratings belong to the assembled HM88542+HM88512 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-HM88542/HM88512 run near 5,400 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM88542/HM88512.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 31.75 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Replacing one half of an adjusted pair without resetting end play negates the 29.37 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (29.37 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 29.37 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 80/97 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM88542/HM88512; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM88542/HM88512?", "a": "4T-HM88542/HM88512 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 73.812 mm outside diameter and 29.37 mm assembled width T (2.906 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 80 kN, C0 97 kN, grease limiting speed 5,400 r/min, oil speed 7,100 r/min, mass about 638 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM88542/HM88512 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM88542 cone or the HM88512 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 80/97 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM88542/HM88512 and a metric ISO 355 tapered bearing?", "a": "4T-HM88542/HM88512 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×73.812×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM88542/HM88512 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM88542/HM88512 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM88542/HM88512 list two speeds, 5,400 and 7,100 r/min?", "a": "The lower figure, 5,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM88542/HM88512 at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM88542-510", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "HM88542-HM88510", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-HM88542 paired with a different cup (HM88510): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm88542-hm88512", "hm88542-hm88512", "HM88542-HM88512", "4T-HM88542-HM88512" ], "locale_variants": {} }, { "sku": "HM89440-HM89410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM89440/HM89410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 76.2, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 105, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 686, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM89440/HM89410 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 31.75×76.2×29.37 mm (assembled width T), for a shaft of about 31.75 mm (1.25 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HM89440 sits in the heavy-medium HM family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 29.37 mm T of each 4T-HM89440/HM89410 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-HM89440/HM89410: press the HM89410 cup square into the 76.2 mm seat first, then bring the HM89440 cone (on its 31.75 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 31.75 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM89440/HM89410.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 31.75 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Quote the full HM89440/HM89410 pair at ordering: the HM89440 cone also ships against sibling cups, and a cup from another reference changes the 29.37 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of HM89440 and HM89410; use undercut shoulders so the rings seat on the face, not on a radius.", "Replacing one half of an adjusted pair without resetting end play negates the 29.37 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 86.5/105 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM89440/HM89410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM89440/HM89410?", "a": "4T-HM89440/HM89410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 76.2 mm outside diameter and 29.37 mm assembled width T (3 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 105 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 686 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM89440/HM89410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM89440 cone or the HM89410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/105 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM89440/HM89410 and a metric ISO 355 tapered bearing?", "a": "4T-HM89440/HM89410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×76.2×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM89440/HM89410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM89440/HM89410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM89440/HM89410 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM89440/HM89410 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM89440", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm89440-hm89410", "hm89440-hm89410", "HM89440-HM89410", "4T-HM89440-HM89410" ], "locale_variants": {} }, { "sku": "3476-3420", "brand": "NTN", "manufacturer_designation": "NTN 4T-3476/3420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 31.75, "D_mm": 79.375, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 103, "static_load_kN": 114, "limiting_speed_rpm": 4900, "max_rpm": 4900, "speed_oil_rpm": 6600, "weight_g": 772, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.25 in (31.75 mm) shaft position as 4T-3476/3420: cone 3476, cup 3420, profiled rollers and a pressed-steel cage, rated 103 kN basic dynamic and 114 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 3476/3420 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 29.37 mm T of each 4T-3476/3420 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 103/114 kN ratings belong to the assembled 3476+3420 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-3476/3420 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 31.75 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3476/3420.", "The pure-numeric inch family at 31.75 mm bore (79.375×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3476/3420 reference at purchase.", "Open 4T-3476/3420 sets have no seals: a hub or gearbox needs external sealing or the 4,900 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 29.37 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 29.37 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 103/114 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3476/3420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3476/3420?", "a": "4T-3476/3420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 31.75 mm bore (1.25 in), 79.375 mm outside diameter and 29.37 mm assembled width T (3.125 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 103 kN, C0 114 kN, grease limiting speed 4,900 r/min, oil speed 6,600 r/min, mass about 772 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3476/3420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3476 cone or the 3420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 103/114 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3476/3420 and a metric ISO 355 tapered bearing?", "a": "4T-3476/3420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 31.75×79.375×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3476/3420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3476/3420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3476/3420 list two speeds, 4,900 and 6,600 r/min?", "a": "The lower figure, 4,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3476/3420 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3476", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3476-3420", "3476-3420", "4T-3476-3420" ], "locale_variants": {} }, { "sku": "M88048-M88010", "brand": "NTN", "manufacturer_designation": "NTN 4T-M88048/M88010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 33.338, "D_mm": 68.262, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 62.5, "static_load_kN": 71, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7500, "weight_g": 379, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-M88048/M88010 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 33.338×68.262×22.225 mm (assembled width T), for a shaft of about 33.338 mm (1.313 in). Reading the designation: 4T-M88048/M88010 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the medium M family lettering ties the pair to its boundary plan. Selection: C 62.5 kN against C0 71 kN gives a C0/C ratio of 1.14 for the 33.338 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for M88010: within the medium M family tables the M88048 cone is listed against several cup options, and it is the cup that fixes the 68.262 mm OD and the 22.225 mm assembled width — quote the full M88048/M88010 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-M88048/M88010 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 33.338 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-M88048/M88010.", "The medium M family at 33.338 mm bore (68.262×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full M88048/M88010 reference at purchase.", "Quote the full M88048/M88010 pair at ordering: the M88048 cone also ships against sibling cups, and a cup from another reference changes the 22.225 mm assembled width and the rating.", "Open 4T-M88048/M88010 sets have no seals: a hub or gearbox needs external sealing or the 5,700 r/min grease figure is meaningless once water reaches the cone rib.", "Shaft and housing fillets must clear the ring chamfers of M88048 and M88010; use undercut shoulders so the rings seat on the face, not on a radius.", "The 62.5/71 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-M88048/M88010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-M88048/M88010?", "a": "4T-M88048/M88010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 33.338 mm bore (1.313 in), 68.262 mm outside diameter and 22.225 mm assembled width T (2.687 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 62.5 kN, C0 71 kN, grease limiting speed 5,700 r/min, oil speed 7,500 r/min, mass about 379 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-M88048/M88010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the M88048 cone or the M88010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 62.5/71 kN ratings change with the cup." }, { "q": "What is the difference between 4T-M88048/M88010 and a metric ISO 355 tapered bearing?", "a": "4T-M88048/M88010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 33.338×68.262×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-M88048/M88010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare M88048/M88010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-M88048/M88010 list two speeds, 5,700 and 7,500 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-M88048/M88010 at 7,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "M88048-010", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-m88048-m88010", "m88048-m88010", "M88048-M88010", "4T-M88048-M88010" ], "locale_variants": {} }, { "sku": "14130-14276", "brand": "NTN", "manufacturer_designation": "NTN 4T-14130/14276", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 33.338, "D_mm": 69.012, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53.5, "static_load_kN": 58, "limiting_speed_rpm": 5600, "max_rpm": 5600, "speed_oil_rpm": 7400, "weight_g": 345, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-14130/14276 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 14130 and cup 14276 delivered as a matched, separable pair of 33.338 mm bore and 69.012 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 14130 identifies the cone of 33.338 mm (1.313 in) bore by catalogue lookup, and 14276 fixes the 69.012 mm OD. Catalogue mass of the 4T-14130/14276 cone-plus-cup set is 345 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 14276: within the pure-numeric inch family tables the 14130 cone is listed against several cup options, and it is the cup that fixes the 69.012 mm OD and the 19.845 mm assembled width — quote the full 14130/14276 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-14130/14276 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 33.338 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-14130/14276.", "The pure-numeric inch family at 33.338 mm bore (69.012×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 14130/14276 reference at purchase.", "Inch and metric bores collide on paper — 33.338 mm is 1.313 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Do not confuse T (19.845 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Inch and metric bores collide on paper — 33.338 mm is 1.313 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 53.5/58 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-14130/14276; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-14130/14276?", "a": "4T-14130/14276 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 33.338 mm bore (1.313 in), 69.012 mm outside diameter and 19.845 mm assembled width T (2.717 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53.5 kN, C0 58 kN, grease limiting speed 5,600 r/min, oil speed 7,400 r/min, mass about 345 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-14130/14276 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 14130 cone or the 14276 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53.5/58 kN ratings change with the cup." }, { "q": "What is the difference between 4T-14130/14276 and a metric ISO 355 tapered bearing?", "a": "4T-14130/14276 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 33.338×69.012×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-14130/14276 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 14130/14276 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-14130/14276 list two speeds, 5,600 and 7,400 r/min?", "a": "The lower figure, 5,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-14130/14276 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "14130", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-14130-14276", "14130-14276", "4T-14130-14276" ], "locale_variants": {} }, { "sku": "2585-2523", "brand": "NTN", "manufacturer_designation": "NTN 4T-2585/2523", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 33.338, "D_mm": 69.85, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 76.5, "static_load_kN": 81.5, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 436, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-2585/2523 is the NTN 4T catalogue entry for a 33.338×69.85×23.812 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 2585/2523 without it. Grease relubrication at the 5,700 r/min limiting speed targets the cone-rib contact; sustaining 7,600 r/min needs an oil supply directed at the large roller ends. Cup-side note for 2523: within the pure-numeric inch family tables the 2585 cone is listed against several cup options, and it is the cup that fixes the 69.85 mm OD and the 23.812 mm assembled width — quote the full 2585/2523 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-2585/2523 run near 5,700 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 33.338 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2585/2523.", "The pure-numeric inch family at 33.338 mm bore (69.85×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2585/2523 reference at purchase.", "Open 4T-2585/2523 sets have no seals: a hub or gearbox needs external sealing or the 5,700 r/min grease figure is meaningless once water reaches the cone rib.", "Grease packs must leave free volume inside the 23.812 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,600 r/min raises temperature and destroys the setting.", "An unloaded 4T-2585/2523 near 5,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 76.5/81.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2585/2523; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2585/2523?", "a": "4T-2585/2523 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 33.338 mm bore (1.313 in), 69.85 mm outside diameter and 23.812 mm assembled width T (2.75 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 76.5 kN, C0 81.5 kN, grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 436 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2585/2523 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2585 cone or the 2523 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 76.5/81.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2585/2523 and a metric ISO 355 tapered bearing?", "a": "4T-2585/2523 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 33.338×69.85×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2585/2523 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2585/2523 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2585/2523 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2585/2523 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2585", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2585-2523", "2585-2523", "4T-2585-2523" ], "locale_variants": {} }, { "sku": "3196-3120", "brand": "NTN", "manufacturer_designation": "NTN 4T-3196/3120", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 33.338, "D_mm": 72.626, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 93.5, "static_load_kN": 98, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7300, "weight_g": 584, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-3196/3120 at 33.338 mm bore (1.313 in), 72.626 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 5,500 r/min and an oil ceiling of 7,300 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 3196/3120 without it. Selection: C 93.5 kN against C0 98 kN gives a C0/C ratio of 1.05 for the 33.338 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 93.5/98 kN ratings belong to the assembled 3196+3120 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-3196/3120 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 33.338 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3196/3120.", "The pure-numeric inch family at 33.338 mm bore (72.626×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3196/3120 reference at purchase.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "ABMA makes the 33.338×72.626 mm envelope interchangeable, not the ratings: NTN prints 93.5/98 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 3196/3120 pair at ordering: the 3196 cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "The 93.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3196/3120; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3196/3120?", "a": "4T-3196/3120 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 33.338 mm bore (1.313 in), 72.626 mm outside diameter and 30.162 mm assembled width T (2.859 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 93.5 kN, C0 98 kN, grease limiting speed 5,500 r/min, oil speed 7,300 r/min, mass about 584 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3196/3120 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3196 cone or the 3120 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 93.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3196/3120 and a metric ISO 355 tapered bearing?", "a": "4T-3196/3120 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 33.338×72.626×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3196/3120 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3196/3120 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3196/3120 list two speeds, 5,500 and 7,300 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3196/3120 at 7,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3196", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3196-3120", "3196-3120", "4T-3196-3120" ], "locale_variants": {} }, { "sku": "HM88547-HM88510", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM88547/HM88510", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 33.338, "D_mm": 73.025, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 80, "static_load_kN": 97, "limiting_speed_rpm": 5400, "max_rpm": 5400, "speed_oil_rpm": 7100, "weight_g": 603, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM88547/HM88510 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 33.338×73.025×29.37 mm (assembled width T), for a shaft of about 33.338 mm (1.313 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HM88547 identifies the cone of 33.338 mm (1.313 in) bore by catalogue lookup, and HM88510 fixes the 73.025 mm OD. Contact-angle geometry of the heavy-medium HM family gives 4T-HM88547/HM88510 its radial/axial load split — at 80/97 kN the static rating is about 1.21× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for HM88510: within the heavy-medium HM family tables the HM88547 cone is listed against several cup options, and it is the cup that fixes the 73.025 mm OD and the 29.37 mm assembled width — quote the full HM88547/HM88510 pair, never the cone alone. Mount the 33.338 mm cone with an induction heater (max 120 °C) and press the 73.025 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 33.338 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM88547/HM88510.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 33.338 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Grease packs must leave free volume inside the 29.37 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,100 r/min raises temperature and destroys the setting.", "An unloaded 4T-HM88547/HM88510 near 5,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "An unloaded 4T-HM88547/HM88510 near 5,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 80/97 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM88547/HM88510; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM88547/HM88510?", "a": "4T-HM88547/HM88510 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 33.338 mm bore (1.313 in), 73.025 mm outside diameter and 29.37 mm assembled width T (2.875 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 80 kN, C0 97 kN, grease limiting speed 5,400 r/min, oil speed 7,100 r/min, mass about 603 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM88547/HM88510 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM88547 cone or the HM88510 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 80/97 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM88547/HM88510 and a metric ISO 355 tapered bearing?", "a": "4T-HM88547/HM88510 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 33.338×73.025×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM88547/HM88510 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM88547/HM88510 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM88547/HM88510 list two speeds, 5,400 and 7,100 r/min?", "a": "The lower figure, 5,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM88547/HM88510 at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM88547", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm88547-hm88510", "hm88547-hm88510", "HM88547-HM88510", "4T-HM88547-HM88510" ], "locale_variants": {} }, { "sku": "2785-2720", "brand": "NTN", "manufacturer_designation": "NTN 4T-2785/2720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 33.338, "D_mm": 76.2, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 81, "static_load_kN": 90.5, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 548, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-2785/2720 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 2785 and cup 2720 delivered as a matched, separable pair of 33.338 mm bore and 76.2 mm outside diameter. Reading the designation: 4T-2785/2720 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 2.4 kN of dynamic capacity per millimetre of bore summarises the 81 kN rating over the 33.338 mm bore — sanity-check any interchange candidate against this ratio and the 23.812 mm T. Cup-side note for 2720: within the pure-numeric inch family tables the 2785 cone is listed against several cup options, and it is the cup that fixes the 76.2 mm OD and the 23.812 mm assembled width — quote the full 2785/2720 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-2785/2720 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 33.338 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2785/2720.", "The pure-numeric inch family at 33.338 mm bore (76.2×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2785/2720 reference at purchase.", "Never drive the 76.2 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "An unloaded 4T-2785/2720 near 5,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of 2785 and 2720; use undercut shoulders so the rings seat on the face, not on a radius.", "The 81/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2785/2720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2785/2720?", "a": "4T-2785/2720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 33.338 mm bore (1.313 in), 76.2 mm outside diameter and 23.812 mm assembled width T (3 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 81 kN, C0 90.5 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 548 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2785/2720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2785 cone or the 2720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 81/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2785/2720 and a metric ISO 355 tapered bearing?", "a": "4T-2785/2720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 33.338×76.2×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2785/2720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2785/2720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2785/2720 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2785/2720 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2785", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2785-2720", "2785-2720", "4T-2785-2720" ], "locale_variants": {} }, { "sku": "HM89443-HM89410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM89443/HM89410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 33.338, "D_mm": 76.2, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 105, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 667, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-HM89443/HM89410 at 33.338 mm bore (1.313 in), 76.2 mm cup OD and 29.37 mm assembled T, with a grease limiting speed of 5,100 r/min and an oil ceiling of 6,800 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote HM89443/HM89410 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 29.37 mm T of each 4T-HM89443/HM89410 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for HM89410: within the heavy-medium HM family tables the HM89443 cone is listed against several cup options, and it is the cup that fixes the 76.2 mm OD and the 29.37 mm assembled width — quote the full HM89443/HM89410 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-HM89443/HM89410, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 33.338 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM89443/HM89410.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 33.338 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Grease packs must leave free volume inside the 29.37 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,800 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 33.338 mm is 1.313 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Shaft and housing fillets must clear the ring chamfers of HM89443 and HM89410; use undercut shoulders so the rings seat on the face, not on a radius.", "The 86.5/105 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM89443/HM89410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM89443/HM89410?", "a": "4T-HM89443/HM89410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 33.338 mm bore (1.313 in), 76.2 mm outside diameter and 29.37 mm assembled width T (3 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 105 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 667 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM89443/HM89410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM89443 cone or the HM89410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/105 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM89443/HM89410 and a metric ISO 355 tapered bearing?", "a": "4T-HM89443/HM89410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 33.338×76.2×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM89443/HM89410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM89443/HM89410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM89443/HM89410 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM89443/HM89410 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM89443", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm89443-hm89410", "hm89443-hm89410", "HM89443-HM89410", "4T-HM89443-HM89410" ], "locale_variants": {} }, { "sku": "HM89444-HM89410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM89444/HM89410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 33.338, "D_mm": 76.2, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 105, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 665, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM89444/HM89410 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-HM89444/HM89410 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the heavy-medium HM family lettering ties the pair to its boundary plan. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 29.37 mm T of each 4T-HM89444/HM89410 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-HM89444/HM89410: press the HM89410 cup square into the 76.2 mm seat first, then bring the HM89444 cone (on its 33.338 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Fillet radii must clear the chamfers of the HM89444 cone and HM89410 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 33.338 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM89444/HM89410.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 33.338 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "An unloaded 4T-HM89444/HM89410 near 5,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Never drive the 76.2 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (29.37 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 86.5/105 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM89444/HM89410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM89444/HM89410?", "a": "4T-HM89444/HM89410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 33.338 mm bore (1.313 in), 76.2 mm outside diameter and 29.37 mm assembled width T (3 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 105 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 665 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM89444/HM89410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM89444 cone or the HM89410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/105 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM89444/HM89410 and a metric ISO 355 tapered bearing?", "a": "4T-HM89444/HM89410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 33.338×76.2×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM89444/HM89410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM89444/HM89410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM89444/HM89410 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM89444/HM89410 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM89444", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm89444-hm89410", "hm89444-hm89410", "HM89444-HM89410", "4T-HM89444-HM89410" ], "locale_variants": {} }, { "sku": "43131-43312", "brand": "NTN", "manufacturer_designation": "NTN 4T-43131/43312", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 33.338, "D_mm": 79.375, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 72.5, "static_load_kN": 67, "limiting_speed_rpm": 5200, "max_rpm": 5200, "speed_oil_rpm": 6900, "weight_g": 568, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-43131/43312 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 33.338×79.375×25.4 mm (assembled width T), for a shaft of about 33.338 mm (1.313 in). Cone and cup of 4T-43131/43312 are separately stocked parts: a worn 43312 cup can be replaced against the existing 43131 cone, provided the new cup carries the identical reference — pairing across references changes the 25.4 mm assembled width and the rating. Grease relubrication at the 5,200 r/min limiting speed targets the cone-rib contact; sustaining 6,900 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-43131/43312: press the 43312 cup square into the 79.375 mm seat first, then bring the 43131 cone (on its 33.338 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-43131/43312 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 33.338 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-43131/43312.", "The pure-numeric inch family at 33.338 mm bore (79.375×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 43131/43312 reference at purchase.", "Do not confuse T (25.4 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 25.4 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 25.4 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 72.5/67 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-43131/43312; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-43131/43312?", "a": "4T-43131/43312 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 33.338 mm bore (1.313 in), 79.375 mm outside diameter and 25.4 mm assembled width T (3.125 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 72.5 kN, C0 67 kN, grease limiting speed 5,200 r/min, oil speed 6,900 r/min, mass about 568 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-43131/43312 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 43131 cone or the 43312 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 72.5/67 kN ratings change with the cup." }, { "q": "What is the difference between 4T-43131/43312 and a metric ISO 355 tapered bearing?", "a": "4T-43131/43312 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 33.338×79.375×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-43131/43312 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 43131/43312 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-43131/43312 list two speeds, 5,200 and 6,900 r/min?", "a": "The lower figure, 5,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-43131/43312 at 6,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "43131", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-43131-43312", "43131-43312", "4T-43131-43312" ], "locale_variants": {} }, { "sku": "LM48548-LM48510", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM48548/LM48510", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 65.088, "B_mm": 18.034, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 51.5, "static_load_kN": 56, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-LM48548/LM48510 is the NTN 4T catalogue entry for a 34.925×65.088×18.034 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — LM48548 sits in the light-medium LM family. Catalogue mass of the 4T-LM48548/LM48510 cone-plus-cup set is 250 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-LM48548/LM48510: press the LM48510 cup square into the 65.088 mm seat first, then bring the LM48548 cone (on its 34.925 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-LM48548/LM48510 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM48548/LM48510.", "The light-medium LM family at 34.925 mm bore (65.088×18.034 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM48548/LM48510 reference at purchase.", "Never drive the 65.088 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (18.034 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Inch and metric bores collide on paper — 34.925 mm is 1.375 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 51.5/56 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM48548/LM48510; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM48548/LM48510?", "a": "4T-LM48548/LM48510 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 65.088 mm outside diameter and 18.034 mm assembled width T (2.563 × 0.71 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 51.5 kN, C0 56 kN, grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 250 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM48548/LM48510 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM48548 cone or the LM48510 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 51.5/56 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM48548/LM48510 and a metric ISO 355 tapered bearing?", "a": "4T-LM48548/LM48510 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×65.088×18.034 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM48548/LM48510 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM48548/LM48510 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM48548/LM48510 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM48548/LM48510 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM48548-510", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925×65.088×18.034 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm48548-lm48510", "lm48548-lm48510", "LM48548-LM48510", "4T-LM48548-LM48510" ], "locale_variants": {} }, { "sku": "LM48548A-LM48510", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM48548A/LM48510", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 65.088, "B_mm": 18.034, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 51.5, "static_load_kN": 56, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 252, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-LM48548A/LM48510 is the NTN 4T catalogue entry for a 34.925×65.088×18.034 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: LM48548A identifies the cone of 34.925 mm (1.375 in) bore by catalogue lookup, and LM48510 fixes the 65.088 mm OD. Speed planning uses both catalogue columns: grease 5,700 r/min is the mechanical ceiling for 4T-LM48548A/LM48510, oil 7,600 r/min with circulating oil — a 1,900 r/min margin at this size. The printed 51.5/56 kN ratings belong to the assembled LM48548A+LM48510 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the LM48548A cone and LM48510 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM48548A/LM48510.", "The light-medium LM family at 34.925 mm bore (65.088×18.034 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM48548A/LM48510 reference at purchase.", "Never drive the 65.088 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume inside the 18.034 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,600 r/min raises temperature and destroys the setting.", "Quote the full LM48548A/LM48510 pair at ordering: the LM48548A cone also ships against sibling cups, and a cup from another reference changes the 18.034 mm assembled width and the rating.", "The 51.5/56 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM48548A/LM48510; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM48548A/LM48510?", "a": "4T-LM48548A/LM48510 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 65.088 mm outside diameter and 18.034 mm assembled width T (2.563 × 0.71 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 51.5 kN, C0 56 kN, grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 252 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM48548A/LM48510 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM48548A cone or the LM48510 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 51.5/56 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM48548A/LM48510 and a metric ISO 355 tapered bearing?", "a": "4T-LM48548A/LM48510 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×65.088×18.034 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM48548A/LM48510 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM48548A/LM48510 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM48548A/LM48510 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM48548A/LM48510 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM48548A-510", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925×65.088×18.034 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm48548a-lm48510", "lm48548a-lm48510", "LM48548A-LM48510", "4T-LM48548A-LM48510" ], "locale_variants": {} }, { "sku": "14137A-14276-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-14137A/14276", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 69.012, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53.5, "static_load_kN": 58, "limiting_speed_rpm": 5600, "max_rpm": 5600, "speed_oil_rpm": 7400, "weight_g": 334, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-14137A/14276 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 14137A and cup 14276 delivered as a matched, separable pair of 34.925 mm bore and 69.012 mm outside diameter. Cone and cup of 4T-14137A/14276 are separately stocked parts: a worn 14276 cup can be replaced against the existing 14137A cone, provided the new cup carries the identical reference — pairing across references changes the 19.845 mm assembled width and the rating. Selection: C 53.5 kN against C0 58 kN gives a C0/C ratio of 1.08 for the 34.925 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-14137A/14276: press the 14276 cup square into the 69.012 mm seat first, then bring the 14137A cone (on its 34.925 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-14137A/14276 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-14137A/14276.", "The pure-numeric inch family at 34.925 mm bore (69.012×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 14137A/14276 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 19.845 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 34.925 mm is 1.375 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-14137A/14276 sets have no seals: a hub or gearbox needs external sealing or the 5,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 53.5/58 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-14137A/14276; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-14137A/14276?", "a": "4T-14137A/14276 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 69.012 mm outside diameter and 19.845 mm assembled width T (2.717 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53.5 kN, C0 58 kN, grease limiting speed 5,600 r/min, oil speed 7,400 r/min, mass about 334 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-14137A/14276 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 14137A cone or the 14276 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53.5/58 kN ratings change with the cup." }, { "q": "What is the difference between 4T-14137A/14276 and a metric ISO 355 tapered bearing?", "a": "4T-14137A/14276 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×69.012×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-14137A/14276 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 14137A/14276 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-14137A/14276 list two speeds, 5,600 and 7,400 r/min?", "a": "The lower figure, 5,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-14137A/14276 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "14137A-14276", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925×69.012×19.845 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "14137a-14276", "4t-14137a-14276", "14137A-14276", "4T-14137A-14276", "14137A-14276-NTN" ], "locale_variants": {} }, { "sku": "HM88649-HM88610", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM88649/HM88610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 72.233, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 72, "static_load_kN": 84.5, "limiting_speed_rpm": 5400, "max_rpm": 5400, "speed_oil_rpm": 7200, "weight_g": 489, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM88649/HM88610 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-HM88649/HM88610 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the heavy-medium HM family lettering ties the pair to its boundary plan. Grease relubrication at the 5,400 r/min limiting speed targets the cone-rib contact; sustaining 7,200 r/min needs an oil supply directed at the large roller ends. Cup-side note for HM88610: within the heavy-medium HM family tables the HM88649 cone is listed against several cup options, and it is the cup that fixes the 72.233 mm OD and the 25.4 mm assembled width — quote the full HM88649/HM88610 pair, never the cone alone. Fillet radii must clear the chamfers of the HM88649 cone and HM88610 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM88649/HM88610.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 34.925 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Do not confuse T (25.4 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-HM88649/HM88610 sets have no seals: a hub or gearbox needs external sealing or the 5,400 r/min grease figure is meaningless once water reaches the cone rib.", "An unloaded 4T-HM88649/HM88610 near 5,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 72/84.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM88649/HM88610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM88649/HM88610?", "a": "4T-HM88649/HM88610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 72.233 mm outside diameter and 25.4 mm assembled width T (2.844 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 72 kN, C0 84.5 kN, grease limiting speed 5,400 r/min, oil speed 7,200 r/min, mass about 489 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM88649/HM88610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM88649 cone or the HM88610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 72/84.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM88649/HM88610 and a metric ISO 355 tapered bearing?", "a": "4T-HM88649/HM88610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×72.233×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM88649/HM88610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM88649/HM88610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM88649/HM88610 list two speeds, 5,400 and 7,200 r/min?", "a": "The lower figure, 5,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM88649/HM88610 at 7,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM88649-610", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925×72.233×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm88649-hm88610", "hm88649-hm88610", "HM88649-HM88610", "4T-HM88649-HM88610" ], "locale_variants": {} }, { "sku": "16137-16284", "brand": "NTN", "manufacturer_designation": "NTN 4T-16137/16284", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 72.238, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53, "static_load_kN": 58.5, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7000, "weight_g": 370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-16137/16284 at 34.925 mm bore (1.375 in), 72.238 mm cup OD and 20.638 mm assembled T, with a grease limiting speed of 5,300 r/min and an oil ceiling of 7,000 r/min. Reading the designation: 4T-16137/16284 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Speed planning uses both catalogue columns: grease 5,300 r/min is the mechanical ceiling for 4T-16137/16284, oil 7,000 r/min with circulating oil — a 1,700 r/min margin at this size. Housing fitment sequence for 4T-16137/16284: press the 16284 cup square into the 72.238 mm seat first, then bring the 16137 cone (on its 34.925 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-16137/16284 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-16137/16284.", "The pure-numeric inch family at 34.925 mm bore (72.238×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 16137/16284 reference at purchase.", "An unloaded 4T-16137/16284 near 5,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 34.925 mm is 1.375 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 34.925 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 53/58.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-16137/16284; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-16137/16284?", "a": "4T-16137/16284 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 72.238 mm outside diameter and 20.638 mm assembled width T (2.844 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53 kN, C0 58.5 kN, grease limiting speed 5,300 r/min, oil speed 7,000 r/min, mass about 370 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-16137/16284 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 16137 cone or the 16284 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53/58.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-16137/16284 and a metric ISO 355 tapered bearing?", "a": "4T-16137/16284 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×72.238×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-16137/16284 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 16137/16284 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-16137/16284 list two speeds, 5,300 and 7,000 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-16137/16284 at 7,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "16137", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-16137-16284", "16137-16284", "4T-16137-16284" ], "locale_variants": {} }, { "sku": "02877-02820", "brand": "NTN", "manufacturer_designation": "NTN 4T-02877/02820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 73.025, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 62.5, "static_load_kN": 68, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7000, "weight_g": 423, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-02877/02820 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 02877/02820 without it. Speed planning uses both catalogue columns: grease 5,300 r/min is the mechanical ceiling for 4T-02877/02820, oil 7,000 r/min with circulating oil — a 1,700 r/min margin at this size. Housing fitment sequence for 4T-02877/02820: press the 02820 cup square into the 73.025 mm seat first, then bring the 02877 cone (on its 34.925 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-02877/02820; reverse the fit logic when the cup rotates.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-02877/02820.", "The pure-numeric inch family at 34.925 mm bore (73.025×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 02877/02820 reference at purchase.", "Inch and metric bores collide on paper — 34.925 mm is 1.375 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 34.925 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 34.925 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 62.5/68 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-02877/02820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-02877/02820?", "a": "4T-02877/02820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 73.025 mm outside diameter and 22.225 mm assembled width T (2.875 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 62.5 kN, C0 68 kN, grease limiting speed 5,300 r/min, oil speed 7,000 r/min, mass about 423 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-02877/02820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 02877 cone or the 02820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 62.5/68 kN ratings change with the cup." }, { "q": "What is the difference between 4T-02877/02820 and a metric ISO 355 tapered bearing?", "a": "4T-02877/02820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×73.025×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-02877/02820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 02877/02820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-02877/02820 list two speeds, 5,300 and 7,000 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-02877/02820 at 7,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "02877", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-02877-02820", "02877-02820", "4T-02877-02820" ], "locale_variants": {} }, { "sku": "02878-02820", "brand": "NTN", "manufacturer_designation": "NTN 4T-02878/02820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 73.025, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 62.5, "static_load_kN": 68, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7000, "weight_g": 426, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 34.925 mm carrying combined radial and thrust load, NTN lists 4T-02878/02820, a single-row 4T tapered roller set of 62.5 kN C and 68 kN C0 inside the 73.025 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 02878 identifies the cone of 34.925 mm (1.375 in) bore by catalogue lookup, and 02820 fixes the 73.025 mm OD. The 19.1 mm radial section over the 34.925 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 02820: within the pure-numeric inch family tables the 02878 cone is listed against several cup options, and it is the cup that fixes the 73.025 mm OD and the 22.225 mm assembled width — quote the full 02878/02820 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-02878/02820, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-02878/02820.", "The pure-numeric inch family at 34.925 mm bore (73.025×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 02878/02820 reference at purchase.", "An unloaded 4T-02878/02820 near 5,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 34.925 mm is 1.375 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Shaft and housing fillets must clear the ring chamfers of 02878 and 02820; use undercut shoulders so the rings seat on the face, not on a radius.", "The 62.5/68 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-02878/02820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-02878/02820?", "a": "4T-02878/02820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 73.025 mm outside diameter and 22.225 mm assembled width T (2.875 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 62.5 kN, C0 68 kN, grease limiting speed 5,300 r/min, oil speed 7,000 r/min, mass about 426 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-02878/02820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 02878 cone or the 02820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 62.5/68 kN ratings change with the cup." }, { "q": "What is the difference between 4T-02878/02820 and a metric ISO 355 tapered bearing?", "a": "4T-02878/02820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×73.025×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-02878/02820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 02878/02820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-02878/02820 list two speeds, 5,300 and 7,000 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-02878/02820 at 7,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "02878", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-02878-02820", "02878-02820", "4T-02878-02820" ], "locale_variants": {} }, { "sku": "25877-25820", "brand": "NTN", "manufacturer_designation": "NTN 4T-25877/25820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 73.025, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 78.5, "static_load_kN": 85, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7100, "weight_g": 470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.375 in (34.925 mm) shaft position as 4T-25877/25820: cone 25877, cup 25820, profiled rollers and a pressed-steel cage, rated 78.5 kN basic dynamic and 85 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 25877 sits in the pure-numeric inch family. Selection: C 78.5 kN against C0 85 kN gives a C0/C ratio of 1.08 for the 34.925 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 78.5/85 kN ratings belong to the assembled 25877+25820 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 34.925 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25877/25820.", "The pure-numeric inch family at 34.925 mm bore (73.025×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25877/25820 reference at purchase.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Quote the full 25877/25820 pair at ordering: the 25877 cone also ships against sibling cups, and a cup from another reference changes the 23.812 mm assembled width and the rating.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 78.5/85 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25877/25820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25877/25820?", "a": "4T-25877/25820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 73.025 mm outside diameter and 23.812 mm assembled width T (2.875 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 78.5 kN, C0 85 kN, grease limiting speed 5,300 r/min, oil speed 7,100 r/min, mass about 470 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25877/25820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25877 cone or the 25820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 78.5/85 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25877/25820 and a metric ISO 355 tapered bearing?", "a": "4T-25877/25820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×73.025×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25877/25820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25877/25820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25877/25820 list two speeds, 5,300 and 7,100 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25877/25820 at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25877-25821", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925×73.025×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25877-25821-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25877 paired with a different cup (25821): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25877-25820", "25877-25820", "4T-25877-25820" ], "locale_variants": {} }, { "sku": "25877-25821-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-25877/25821", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 73.025, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 78.5, "static_load_kN": 85, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7100, "weight_g": 473, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 34.925 mm carrying combined radial and thrust load, NTN lists 4T-25877/25821, a single-row 4T tapered roller set of 78.5 kN C and 85 kN C0 inside the 73.025 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 25877/25821 without it. Selection: C 78.5 kN against C0 85 kN gives a C0/C ratio of 1.08 for the 34.925 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 25821: within the pure-numeric inch family tables the 25877 cone is listed against several cup options, and it is the cup that fixes the 73.025 mm OD and the 23.812 mm assembled width — quote the full 25877/25821 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 34.925 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25877/25821.", "The pure-numeric inch family at 34.925 mm bore (73.025×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25877/25821 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 34.925 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Inch and metric bores collide on paper — 34.925 mm is 1.375 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 78.5/85 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25877/25821; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25877/25821?", "a": "4T-25877/25821 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 73.025 mm outside diameter and 23.812 mm assembled width T (2.875 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 78.5 kN, C0 85 kN, grease limiting speed 5,300 r/min, oil speed 7,100 r/min, mass about 473 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25877/25821 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25877 cone or the 25821 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 78.5/85 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25877/25821 and a metric ISO 355 tapered bearing?", "a": "4T-25877/25821 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×73.025×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25877/25821 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25877/25821 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25877/25821 list two speeds, 5,300 and 7,100 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25877/25821 at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25877-25821", "equiv_brand": "SKF", "level": "partial", "note": "Same 34.925×73.025×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25877-25820", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25877 paired with a different cup (25820): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25877-25821", "25877-25821", "4T-25877-25821", "25877-25821-NTN" ], "locale_variants": {} }, { "sku": "2793-2735X", "brand": "NTN", "manufacturer_designation": "NTN 4T-2793/2735X", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 73.025, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 81, "static_load_kN": 90.5, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 444, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-2793/2735X is the NTN 4T catalogue entry for a 34.925×73.025×23.812 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-2793/2735X are separately stocked parts: a worn 2735X cup can be replaced against the existing 2793 cone, provided the new cup carries the identical reference — pairing across references changes the 23.812 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 5,100 r/min is the mechanical ceiling for 4T-2793/2735X, oil 6,800 r/min with circulating oil — a 1,700 r/min margin at this size. The printed 81/90.5 kN ratings belong to the assembled 2793+2735X pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 34.925 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2793/2735X.", "The pure-numeric inch family at 34.925 mm bore (73.025×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2793/2735X reference at purchase.", "Never drive the 73.025 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 4T-2793/2735X sets have no seals: a hub or gearbox needs external sealing or the 5,100 r/min grease figure is meaningless once water reaches the cone rib.", "Never drive the 73.025 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 81/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2793/2735X; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2793/2735X?", "a": "4T-2793/2735X is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 73.025 mm outside diameter and 23.812 mm assembled width T (2.875 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 81 kN, C0 90.5 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 444 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2793/2735X interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2793 cone or the 2735X cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 81/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2793/2735X and a metric ISO 355 tapered bearing?", "a": "4T-2793/2735X follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×73.025×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2793/2735X mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2793/2735X references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2793/2735X list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2793/2735X at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2793-2720", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-2793 paired with a different cup (2720): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "2793-2735x", "4t-2793-2735x", "2793-2735X", "4T-2793-2735X" ], "locale_variants": {} }, { "sku": "2878-2820", "brand": "NTN", "manufacturer_designation": "NTN 4T-2878/2820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 73.025, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 69.5, "static_load_kN": 75.5, "limiting_speed_rpm": 5200, "max_rpm": 5200, "speed_oil_rpm": 7000, "weight_g": 435, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-2878/2820 at 34.925 mm bore (1.375 in), 73.025 mm cup OD and 22.225 mm assembled T, with a grease limiting speed of 5,200 r/min and an oil ceiling of 7,000 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 2878 identifies the cone of 34.925 mm (1.375 in) bore by catalogue lookup, and 2820 fixes the 73.025 mm OD. Grease relubrication at the 5,200 r/min limiting speed targets the cone-rib contact; sustaining 7,000 r/min needs an oil supply directed at the large roller ends. The printed 69.5/75.5 kN ratings belong to the assembled 2878+2820 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-2878/2820, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2878/2820.", "The pure-numeric inch family at 34.925 mm bore (73.025×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2878/2820 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 2878 and 2820; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of 2878 and 2820; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full 2878/2820 pair at ordering: the 2878 cone also ships against sibling cups, and a cup from another reference changes the 22.225 mm assembled width and the rating.", "The 69.5/75.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2878/2820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2878/2820?", "a": "4T-2878/2820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 73.025 mm outside diameter and 22.225 mm assembled width T (2.875 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 69.5 kN, C0 75.5 kN, grease limiting speed 5,200 r/min, oil speed 7,000 r/min, mass about 435 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2878/2820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2878 cone or the 2820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 69.5/75.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2878/2820 and a metric ISO 355 tapered bearing?", "a": "4T-2878/2820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×73.025×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2878/2820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2878/2820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2878/2820 list two speeds, 5,200 and 7,000 r/min?", "a": "The lower figure, 5,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2878/2820 at 7,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2878", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2878-2820", "2878-2820", "4T-2878-2820" ], "locale_variants": {} }, { "sku": "2793-2720", "brand": "NTN", "manufacturer_designation": "NTN 4T-2793/2720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 76.2, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 81, "static_load_kN": 90.5, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 534, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.375 in (34.925 mm) shaft position as 4T-2793/2720: cone 2793, cup 2720, profiled rollers and a pressed-steel cage, rated 81 kN basic dynamic and 90.5 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 2793/2720 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 23.812 mm T of each 4T-2793/2720 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-2793/2720: press the 2720 cup square into the 76.2 mm seat first, then bring the 2793 cone (on its 34.925 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 34.925 mm cone with an induction heater (max 120 °C) and press the 76.2 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2793/2720.", "The pure-numeric inch family at 34.925 mm bore (76.2×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2793/2720 reference at purchase.", "Inch and metric bores collide on paper — 34.925 mm is 1.375 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 34.925 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 34.925×76.2 mm envelope interchangeable, not the ratings: NTN prints 81/90.5 kN for this execution and another make of the same number can differ in roller complement.", "The 81/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2793/2720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2793/2720?", "a": "4T-2793/2720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 76.2 mm outside diameter and 23.812 mm assembled width T (3 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 81 kN, C0 90.5 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 534 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2793/2720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2793 cone or the 2720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 81/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2793/2720 and a metric ISO 355 tapered bearing?", "a": "4T-2793/2720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×76.2×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2793/2720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2793/2720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2793/2720 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2793/2720 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2793-2735X", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-2793 paired with a different cup (2735X): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=178", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2793-2720", "2793-2720", "4T-2793-2720" ], "locale_variants": {} }, { "sku": "2796-2729", "brand": "NTN", "manufacturer_designation": "NTN 4T-2796/2729", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 76.2, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 81, "static_load_kN": 90.5, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 536, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.375 in (34.925 mm) shaft position as 4T-2796/2729: cone 2796, cup 2729, profiled rollers and a pressed-steel cage, rated 81 kN basic dynamic and 90.5 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 2796/2729 without it. Contact-angle geometry of the pure-numeric inch family gives 4T-2796/2729 its radial/axial load split — at 81/90.5 kN the static rating is about 1.12× C, typical of inch tapered sets proportioned for combined duty. The printed 81/90.5 kN ratings belong to the assembled 2796+2729 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 34.925 mm cone with an induction heater (max 120 °C) and press the 76.2 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2796/2729.", "The pure-numeric inch family at 34.925 mm bore (76.2×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2796/2729 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 34.925 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 2796/2729 pair at ordering: the 2796 cone also ships against sibling cups, and a cup from another reference changes the 23.812 mm assembled width and the rating.", "Grease packs must leave free volume inside the 23.812 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,800 r/min raises temperature and destroys the setting.", "The 81/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2796/2729; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2796/2729?", "a": "4T-2796/2729 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 76.2 mm outside diameter and 23.812 mm assembled width T (3 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 81 kN, C0 90.5 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 536 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2796/2729 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2796 cone or the 2729 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 81/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2796/2729 and a metric ISO 355 tapered bearing?", "a": "4T-2796/2729 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×76.2×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2796/2729 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2796/2729 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2796/2729 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2796/2729 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2796", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2796-2729", "2796-2729", "4T-2796-2729" ], "locale_variants": {} }, { "sku": "31593-31520", "brand": "NTN", "manufacturer_designation": "NTN 4T-31593/31520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 76.2, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 89.5, "static_load_kN": 97, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 626, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.375 in (34.925 mm) shaft position as 4T-31593/31520: cone 31593, cup 31520, profiled rollers and a pressed-steel cage, rated 89.5 kN basic dynamic and 97 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 31593 identifies the cone of 34.925 mm (1.375 in) bore by catalogue lookup, and 31520 fixes the 76.2 mm OD. The 20.6 mm radial section over the 34.925 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 31520: within the pure-numeric inch family tables the 31593 cone is listed against several cup options, and it is the cup that fixes the 76.2 mm OD and the 29.37 mm assembled width — quote the full 31593/31520 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 34.925 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-31593/31520.", "The pure-numeric inch family at 34.925 mm bore (76.2×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 31593/31520 reference at purchase.", "ABMA makes the 34.925×76.2 mm envelope interchangeable, not the ratings: NTN prints 89.5/97 kN for this execution and another make of the same number can differ in roller complement.", "Replacing one half of an adjusted pair without resetting end play negates the 29.37 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Quote the full 31593/31520 pair at ordering: the 31593 cone also ships against sibling cups, and a cup from another reference changes the 29.37 mm assembled width and the rating.", "The 89.5/97 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-31593/31520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-31593/31520?", "a": "4T-31593/31520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 76.2 mm outside diameter and 29.37 mm assembled width T (3 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 89.5 kN, C0 97 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 626 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-31593/31520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 31593 cone or the 31520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 89.5/97 kN ratings change with the cup." }, { "q": "What is the difference between 4T-31593/31520 and a metric ISO 355 tapered bearing?", "a": "4T-31593/31520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×76.2×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-31593/31520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 31593/31520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-31593/31520 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-31593/31520 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "31593", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-31593-31520", "31593-31520", "4T-31593-31520" ], "locale_variants": {} }, { "sku": "31594-31520", "brand": "NTN", "manufacturer_designation": "NTN 4T-31594/31520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 76.2, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 89.5, "static_load_kN": 97, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 628, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-31594/31520 is the NTN 4T catalogue entry for a 34.925×76.2×29.37 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-31594/31520 are separately stocked parts: a worn 31520 cup can be replaced against the existing 31594 cone, provided the new cup carries the identical reference — pairing across references changes the 29.37 mm assembled width and the rating. Grease relubrication at the 5,100 r/min limiting speed targets the cone-rib contact; sustaining 6,800 r/min needs an oil supply directed at the large roller ends. The printed 89.5/97 kN ratings belong to the assembled 31594+31520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 31594 cone and 31520 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-31594/31520.", "The pure-numeric inch family at 34.925 mm bore (76.2×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 31594/31520 reference at purchase.", "Quote the full 31594/31520 pair at ordering: the 31594 cone also ships against sibling cups, and a cup from another reference changes the 29.37 mm assembled width and the rating.", "An unloaded 4T-31594/31520 near 5,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Grease packs must leave free volume inside the 29.37 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,800 r/min raises temperature and destroys the setting.", "The 89.5/97 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-31594/31520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-31594/31520?", "a": "4T-31594/31520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 76.2 mm outside diameter and 29.37 mm assembled width T (3 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 89.5 kN, C0 97 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 628 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-31594/31520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 31594 cone or the 31520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 89.5/97 kN ratings change with the cup." }, { "q": "What is the difference between 4T-31594/31520 and a metric ISO 355 tapered bearing?", "a": "4T-31594/31520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×76.2×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-31594/31520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 31594/31520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-31594/31520 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-31594/31520 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "31594", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-31594-31520", "31594-31520", "4T-31594-31520" ], "locale_variants": {} }, { "sku": "HM89446-HM89410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM89446/HM89410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 76.2, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 105, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 646, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-HM89446/HM89410 denotes the heavy-medium HM family of NTN inch tapered roller bearings — cone HM89446 and cup HM89410 delivered as a matched, separable pair of 34.925 mm bore and 76.2 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote HM89446/HM89410 without it. Speed planning uses both catalogue columns: grease 5,100 r/min is the mechanical ceiling for 4T-HM89446/HM89410, oil 6,800 r/min with circulating oil — a 1,700 r/min margin at this size. The printed 86.5/105 kN ratings belong to the assembled HM89446+HM89410 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-HM89446/HM89410 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM89446/HM89410.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 34.925 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Fit selection follows the rotating ring: a rotating cone on a 34.925 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (29.37 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Inch and metric bores collide on paper — 34.925 mm is 1.375 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 86.5/105 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM89446/HM89410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM89446/HM89410?", "a": "4T-HM89446/HM89410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 76.2 mm outside diameter and 29.37 mm assembled width T (3 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 105 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 646 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM89446/HM89410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM89446 cone or the HM89410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/105 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM89446/HM89410 and a metric ISO 355 tapered bearing?", "a": "4T-HM89446/HM89410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×76.2×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM89446/HM89410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM89446/HM89410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM89446/HM89410 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM89446/HM89410 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM89446-410", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm89446-hm89410", "hm89446-hm89410", "HM89446-HM89410", "4T-HM89446-HM89410" ], "locale_variants": {} }, { "sku": "3478-3420", "brand": "NTN", "manufacturer_designation": "NTN 4T-3478/3420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 79.375, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 103, "static_load_kN": 114, "limiting_speed_rpm": 4900, "max_rpm": 4900, "speed_oil_rpm": 6600, "weight_g": 731, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3478/3420 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 34.925×79.375×29.37 mm (assembled width T), for a shaft of about 34.925 mm (1.375 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 3478/3420 without it. Contact-angle geometry of the pure-numeric inch family gives 4T-3478/3420 its radial/axial load split — at 103/114 kN the static rating is about 1.11× C, typical of inch tapered sets proportioned for combined duty. The printed 103/114 kN ratings belong to the assembled 3478+3420 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-3478/3420; reverse the fit logic when the cup rotates.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3478/3420.", "The pure-numeric inch family at 34.925 mm bore (79.375×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3478/3420 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 34.925 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (29.37 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-3478/3420 sets have no seals: a hub or gearbox needs external sealing or the 4,900 r/min grease figure is meaningless once water reaches the cone rib.", "The 103/114 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3478/3420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3478/3420?", "a": "4T-3478/3420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 79.375 mm outside diameter and 29.37 mm assembled width T (3.125 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 103 kN, C0 114 kN, grease limiting speed 4,900 r/min, oil speed 6,600 r/min, mass about 731 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3478/3420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3478 cone or the 3420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 103/114 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3478/3420 and a metric ISO 355 tapered bearing?", "a": "4T-3478/3420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×79.375×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3478/3420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3478/3420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3478/3420 list two speeds, 4,900 and 6,600 r/min?", "a": "The lower figure, 4,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3478/3420 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3478", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3478-3420", "3478-3420", "4T-3478-3420" ], "locale_variants": {} }, { "sku": "3379-3320", "brand": "NTN", "manufacturer_designation": "NTN 4T-3379/3320", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 80.167, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 105, "static_load_kN": 112, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 736, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3379/3320 is the NTN 4T catalogue entry for a 34.925×80.167×29.37 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 3379/3320 without it. Imperial cross-check for the drawing: 34.925×80.167×29.37 mm converts to 1.375 × 3.156 × 1.156 in; the ABMA envelope swaps with like-numbered inch parts but the 105/112 kN ratings are NTN-specific. Cup-side note for 3320: within the pure-numeric inch family tables the 3379 cone is listed against several cup options, and it is the cup that fixes the 80.167 mm OD and the 29.37 mm assembled width — quote the full 3379/3320 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 34.925 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3379/3320.", "The pure-numeric inch family at 34.925 mm bore (80.167×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3379/3320 reference at purchase.", "ABMA makes the 34.925×80.167 mm envelope interchangeable, not the ratings: NTN prints 105/112 kN for this execution and another make of the same number can differ in roller complement.", "Grease packs must leave free volume inside the 29.37 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,400 r/min raises temperature and destroys the setting.", "Replacing one half of an adjusted pair without resetting end play negates the 29.37 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 105/112 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3379/3320; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3379/3320?", "a": "4T-3379/3320 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 80.167 mm outside diameter and 29.37 mm assembled width T (3.156 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 105 kN, C0 112 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 736 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3379/3320 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3379 cone or the 3320 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 105/112 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3379/3320 and a metric ISO 355 tapered bearing?", "a": "4T-3379/3320 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×80.167×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3379/3320 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3379/3320 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3379/3320 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3379/3320 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3379", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3379-3320", "3379-3320", "4T-3379-3320" ], "locale_variants": {} }, { "sku": "3872-3820", "brand": "NTN", "manufacturer_designation": "NTN 4T-3872/3820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.925, "D_mm": 85.725, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 116, "static_load_kN": 132, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 902, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3872/3820 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-3872/3820 are separately stocked parts: a worn 3820 cup can be replaced against the existing 3872 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 4,500 r/min is the mechanical ceiling for 4T-3872/3820, oil 6,000 r/min with circulating oil — a 1,500 r/min margin at this size. Cup-side note for 3820: within the pure-numeric inch family tables the 3872 cone is listed against several cup options, and it is the cup that fixes the 85.725 mm OD and the 30.162 mm assembled width — quote the full 3872/3820 pair, never the cone alone. Fillet radii must clear the chamfers of the 3872 cone and 3820 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 34.925 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3872/3820.", "The pure-numeric inch family at 34.925 mm bore (85.725×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3872/3820 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 34.925 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Never drive the 85.725 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 116/132 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3872/3820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3872/3820?", "a": "4T-3872/3820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 85.725 mm outside diameter and 30.162 mm assembled width T (3.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 116 kN, C0 132 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 902 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3872/3820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3872 cone or the 3820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 116/132 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3872/3820 and a metric ISO 355 tapered bearing?", "a": "4T-3872/3820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.925×85.725×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3872/3820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3872/3820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3872/3820 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3872/3820 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3872", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3872-3820", "3872-3820", "4T-3872-3820" ], "locale_variants": {} }, { "sku": "14139-14276", "brand": "NTN", "manufacturer_designation": "NTN 4T-14139/14276", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.976, "D_mm": 69.012, "B_mm": 19.845, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53.5, "static_load_kN": 58, "limiting_speed_rpm": 5600, "max_rpm": 5600, "speed_oil_rpm": 7400, "weight_g": 330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.377 in (34.976 mm) shaft position as 4T-14139/14276: cone 14139, cup 14276, profiled rollers and a pressed-steel cage, rated 53.5 kN basic dynamic and 58 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 14139/14276 without it. Speed planning uses both catalogue columns: grease 5,600 r/min is the mechanical ceiling for 4T-14139/14276, oil 7,400 r/min with circulating oil — a 1,800 r/min margin at this size. Housing fitment sequence for 4T-14139/14276: press the 14276 cup square into the 69.012 mm seat first, then bring the 14139 cone (on its 34.976 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-14139/14276; reverse the fit logic when the cup rotates.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 34.976 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-14139/14276.", "The pure-numeric inch family at 34.976 mm bore (69.012×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 14139/14276 reference at purchase.", "Quote the full 14139/14276 pair at ordering: the 14139 cone also ships against sibling cups, and a cup from another reference changes the 19.845 mm assembled width and the rating.", "Do not confuse T (19.845 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-14139/14276 sets have no seals: a hub or gearbox needs external sealing or the 5,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 53.5/58 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-14139/14276; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-14139/14276?", "a": "4T-14139/14276 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.976 mm bore (1.377 in), 69.012 mm outside diameter and 19.845 mm assembled width T (2.717 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53.5 kN, C0 58 kN, grease limiting speed 5,600 r/min, oil speed 7,400 r/min, mass about 330 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-14139/14276 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 14139 cone or the 14276 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53.5/58 kN ratings change with the cup." }, { "q": "What is the difference between 4T-14139/14276 and a metric ISO 355 tapered bearing?", "a": "4T-14139/14276 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.976×69.012×19.845 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-14139/14276 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 14139/14276 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-14139/14276 list two speeds, 5,600 and 7,400 r/min?", "a": "The lower figure, 5,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-14139/14276 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "14139", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-14139-14276", "14139-14276", "4T-14139-14276" ], "locale_variants": {} }, { "sku": "L68149-L68111", "brand": "NTN", "manufacturer_designation": "NTN 4T-L68149/L68111", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.988, "D_mm": 59.974, "B_mm": 15.875, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 39, "static_load_kN": 47.5, "limiting_speed_rpm": 6100, "max_rpm": 6100, "speed_oil_rpm": 8100, "weight_g": 179, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 34.988 mm carrying combined radial and thrust load, NTN lists 4T-L68149/L68111, a single-row 4T tapered roller set of 39 kN C and 47.5 kN C0 inside the 59.974 mm OD cup. Reading the designation: 4T-L68149/L68111 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the light L family lettering ties the pair to its boundary plan. Speed planning uses both catalogue columns: grease 6,100 r/min is the mechanical ceiling for 4T-L68149/L68111, oil 8,100 r/min with circulating oil — a 2,000 r/min margin at this size. Cup-side note for L68111: within the light L family tables the L68149 cone is listed against several cup options, and it is the cup that fixes the 59.974 mm OD and the 15.875 mm assembled width — quote the full L68149/L68111 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 34.988 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 34.988 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-L68149/L68111.", "The light L family at 34.988 mm bore (59.974×15.875 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L68149/L68111 reference at purchase.", "Open 4T-L68149/L68111 sets have no seals: a hub or gearbox needs external sealing or the 6,100 r/min grease figure is meaningless once water reaches the cone rib.", "Quote the full L68149/L68111 pair at ordering: the L68149 cone also ships against sibling cups, and a cup from another reference changes the 15.875 mm assembled width and the rating.", "Do not confuse T (15.875 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 39/47.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L68149/L68111; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L68149/L68111?", "a": "4T-L68149/L68111 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.988 mm bore (1.377 in), 59.974 mm outside diameter and 15.875 mm assembled width T (2.361 × 0.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 39 kN, C0 47.5 kN, grease limiting speed 6,100 r/min, oil speed 8,100 r/min, mass about 179 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L68149/L68111 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L68149 cone or the L68111 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 39/47.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L68149/L68111 and a metric ISO 355 tapered bearing?", "a": "4T-L68149/L68111 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.988×59.974×15.875 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L68149/L68111 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L68149/L68111 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L68149/L68111 list two speeds, 6,100 and 8,100 r/min?", "a": "The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L68149/L68111 at 8,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L68149-110", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "L68149-111", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l68149-l68111", "l68149-l68111", "L68149-L68111", "4T-L68149-L68111" ], "locale_variants": {} }, { "sku": "LM78349-LM78310C", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM78349/LM78310C", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.988, "D_mm": 61.973, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 41, "static_load_kN": 48, "limiting_speed_rpm": 5900, "max_rpm": 5900, "speed_oil_rpm": 7900, "weight_g": 218, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-LM78349/LM78310C at 34.988 mm bore (1.377 in), 61.973 mm cup OD and 18 mm assembled T, with a grease limiting speed of 5,900 r/min and an oil ceiling of 7,900 r/min. Cone and cup of 4T-LM78349/LM78310C are separately stocked parts: a worn LM78310C cup can be replaced against the existing LM78349 cone, provided the new cup carries the identical reference — pairing across references changes the 18 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 5,900 r/min is the mechanical ceiling for 4T-LM78349/LM78310C, oil 7,900 r/min with circulating oil — a 2,000 r/min margin at this size. The printed 41/48 kN ratings belong to the assembled LM78349+LM78310C pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-LM78349/LM78310C sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 34.988 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM78349/LM78310C.", "The light-medium LM family at 34.988 mm bore (61.973×18 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM78349/LM78310C reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 18 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 18 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 18 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 41/48 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM78349/LM78310C; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM78349/LM78310C?", "a": "4T-LM78349/LM78310C is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.988 mm bore (1.377 in), 61.973 mm outside diameter and 18 mm assembled width T (2.44 × 0.709 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 41 kN, C0 48 kN, grease limiting speed 5,900 r/min, oil speed 7,900 r/min, mass about 218 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM78349/LM78310C interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM78349 cone or the LM78310C cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 41/48 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM78349/LM78310C and a metric ISO 355 tapered bearing?", "a": "4T-LM78349/LM78310C follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.988×61.973×18 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM78349/LM78310C mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM78349/LM78310C references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM78349/LM78310C list two speeds, 5,900 and 7,900 r/min?", "a": "The lower figure, 5,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM78349/LM78310C at 7,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM78349", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm78349-lm78310c", "lm78349-lm78310c", "LM78349-LM78310C", "4T-LM78349-LM78310C" ], "locale_variants": {} }, { "sku": "LM78349A-LM78310A", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM78349A/LM78310A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 34.988, "D_mm": 61.973, "B_mm": 16.7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 41, "static_load_kN": 48, "limiting_speed_rpm": 5900, "max_rpm": 5900, "speed_oil_rpm": 7900, "weight_g": 206, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-LM78349A/LM78310A is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 34.988×61.973×16.7 mm (assembled width T), for a shaft of about 34.988 mm (1.377 in). Reading the designation: 4T-LM78349A/LM78310A follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the light-medium LM family lettering ties the pair to its boundary plan. Selection: C 41 kN against C0 48 kN gives a C0/C ratio of 1.17 for the 34.988 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 41/48 kN ratings belong to the assembled LM78349A+LM78310A pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-LM78349A/LM78310A is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 34.988 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM78349A/LM78310A.", "The light-medium LM family at 34.988 mm bore (61.973×16.7 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM78349A/LM78310A reference at purchase.", "Do not confuse T (16.7 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Never drive the 61.973 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never drive the 61.973 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 41/48 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM78349A/LM78310A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM78349A/LM78310A?", "a": "4T-LM78349A/LM78310A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.988 mm bore (1.377 in), 61.973 mm outside diameter and 16.7 mm assembled width T (2.44 × 0.657 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 41 kN, C0 48 kN, grease limiting speed 5,900 r/min, oil speed 7,900 r/min, mass about 206 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM78349A/LM78310A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM78349A cone or the LM78310A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 41/48 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM78349A/LM78310A and a metric ISO 355 tapered bearing?", "a": "4T-LM78349A/LM78310A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.988×61.973×16.7 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM78349A/LM78310A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM78349A/LM78310A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM78349A/LM78310A list two speeds, 5,900 and 7,900 r/min?", "a": "The lower figure, 5,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM78349A/LM78310A at 7,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM78349A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm78349a-lm78310a", "lm78349a-lm78310a", "LM78349A-LM78310A", "4T-LM78349A-LM78310A" ], "locale_variants": {} }, { "sku": "JS3549A-JS3510", "brand": "NTN", "manufacturer_designation": "NTN 4T-JS3549A/JS3510", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 70, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 69, "static_load_kN": 78, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7300, "weight_g": 420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-JS3549A/JS3510 denotes the JS prefixed family of NTN inch tapered roller bearings — cone JS3549A and cup JS3510 delivered as a matched, separable pair of 35 mm bore and 70 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — JS3549A sits in the JS prefixed family. The 2.0 kN of dynamic capacity per millimetre of bore summarises the 69 kN rating over the 35 mm bore — sanity-check any interchange candidate against this ratio and the 24 mm T. Cup-side note for JS3510: within the JS prefixed family tables the JS3549A cone is listed against several cup options, and it is the cup that fixes the 70 mm OD and the 24 mm assembled width — quote the full JS3549A/JS3510 pair, never the cone alone. Mount the 35 mm cone with an induction heater (max 120 °C) and press the 70 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 35 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-JS3549A/JS3510.", "The J-prefixed JS3549A code belongs to a metric-envelope inch family: its 35 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Fit selection follows the rotating ring: a rotating cone on a 35 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Inch and metric bores collide on paper — 35 mm is 1.378 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Quote the full JS3549A/JS3510 pair at ordering: the JS3549A cone also ships against sibling cups, and a cup from another reference changes the 24 mm assembled width and the rating.", "The 69/78 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JS3549A/JS3510; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JS3549A/JS3510?", "a": "4T-JS3549A/JS3510 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 35 mm bore (1.378 in), 70 mm outside diameter and 24 mm assembled width T (2.756 × 0.945 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 69 kN, C0 78 kN, grease limiting speed 5,500 r/min, oil speed 7,300 r/min, mass about 420 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JS3549A/JS3510 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JS3549A cone or the JS3510 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 69/78 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JS3549A/JS3510 and a metric ISO 355 tapered bearing?", "a": "4T-JS3549A/JS3510 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 35×70×24 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JS3549A/JS3510 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JS3549A/JS3510 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JS3549A/JS3510 list two speeds, 5,500 and 7,300 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JS3549A/JS3510 at 7,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JS3549A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-js3549a-js3510", "4t-js3549a-js3510", "js3549a-js3510", "JS3549A-JS3510", "4T-JS3549A-JS3510" ], "locale_variants": {} }, { "sku": "26883-26822", "brand": "NTN", "manufacturer_designation": "NTN 4T-26883/26822", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 35, "D_mm": 79.375, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 97.5, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-26883/26822 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 26883 and cup 26822 delivered as a matched, separable pair of 35 mm bore and 79.375 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 26883 sits in the pure-numeric inch family. Catalogue mass of the 4T-26883/26822 cone-plus-cup set is 610 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 85/97.5 kN ratings belong to the assembled 26883+26822 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 35 mm cone with an induction heater (max 120 °C) and press the 79.375 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 35 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-26883/26822.", "The pure-numeric inch family at 35 mm bore (79.375×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 26883/26822 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 26883 and 26822; use undercut shoulders so the rings seat on the face, not on a radius.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Shaft and housing fillets must clear the ring chamfers of 26883 and 26822; use undercut shoulders so the rings seat on the face, not on a radius.", "The 85/97.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-26883/26822; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-26883/26822?", "a": "4T-26883/26822 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 35 mm bore (1.378 in), 79.375 mm outside diameter and 23.812 mm assembled width T (3.125 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 97.5 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 610 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-26883/26822 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 26883 cone or the 26822 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/97.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-26883/26822 and a metric ISO 355 tapered bearing?", "a": "4T-26883/26822 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 35×79.375×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-26883/26822 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 26883/26822 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-26883/26822 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-26883/26822 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "26883", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-26883-26822", "26883-26822", "4T-26883-26822" ], "locale_variants": {} }, { "sku": "HM88648-HM88610", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM88648/HM88610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 35.717, "D_mm": 72.233, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 72, "static_load_kN": 84.5, "limiting_speed_rpm": 5400, "max_rpm": 5400, "speed_oil_rpm": 7200, "weight_g": 477, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-HM88648/HM88610 at 35.717 mm bore (1.406 in), 72.233 mm cup OD and 25.4 mm assembled T, with a grease limiting speed of 5,400 r/min and an oil ceiling of 7,200 r/min. Cone and cup of 4T-HM88648/HM88610 are separately stocked parts: a worn HM88610 cup can be replaced against the existing HM88648 cone, provided the new cup carries the identical reference — pairing across references changes the 25.4 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 5,400 r/min is the mechanical ceiling for 4T-HM88648/HM88610, oil 7,200 r/min with circulating oil — a 1,800 r/min margin at this size. Cup-side note for HM88610: within the heavy-medium HM family tables the HM88648 cone is listed against several cup options, and it is the cup that fixes the 72.233 mm OD and the 25.4 mm assembled width — quote the full HM88648/HM88610 pair, never the cone alone. Fillet radii must clear the chamfers of the HM88648 cone and HM88610 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 35.717 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM88648/HM88610.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 35.717 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Quote the full HM88648/HM88610 pair at ordering: the HM88648 cone also ships against sibling cups, and a cup from another reference changes the 25.4 mm assembled width and the rating.", "Open 4T-HM88648/HM88610 sets have no seals: a hub or gearbox needs external sealing or the 5,400 r/min grease figure is meaningless once water reaches the cone rib.", "An unloaded 4T-HM88648/HM88610 near 5,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 72/84.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM88648/HM88610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM88648/HM88610?", "a": "4T-HM88648/HM88610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 35.717 mm bore (1.406 in), 72.233 mm outside diameter and 25.4 mm assembled width T (2.844 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 72 kN, C0 84.5 kN, grease limiting speed 5,400 r/min, oil speed 7,200 r/min, mass about 477 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM88648/HM88610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM88648 cone or the HM88610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 72/84.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM88648/HM88610 and a metric ISO 355 tapered bearing?", "a": "4T-HM88648/HM88610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 35.717×72.233×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM88648/HM88610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM88648/HM88610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM88648/HM88610 list two speeds, 5,400 and 7,200 r/min?", "a": "The lower figure, 5,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM88648/HM88610 at 7,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM88648-610", "equiv_brand": "SKF", "level": "partial", "note": "Same 35.717×72.233×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM88648-HM88611AS", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-HM88648 paired with a different cup (HM88611AS): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm88648-hm88610", "hm88648-hm88610", "HM88648-HM88610", "4T-HM88648-HM88610" ], "locale_variants": {} }, { "sku": "HM88648-HM88611AS", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM88648/HM88611AS", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 35.717, "D_mm": 72.626, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 72, "static_load_kN": 84.5, "limiting_speed_rpm": 5400, "max_rpm": 5400, "speed_oil_rpm": 7200, "weight_g": 482, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 35.717 mm carrying combined radial and thrust load, NTN lists 4T-HM88648/HM88611AS, a single-row 4T tapered roller set of 72 kN C and 84.5 kN C0 inside the 72.626 mm OD cup. Reading the designation: 4T-HM88648/HM88611AS follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the heavy-medium HM family lettering ties the pair to its boundary plan. The 18.5 mm radial section over the 35.717 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for HM88611AS: within the heavy-medium HM family tables the HM88648 cone is listed against several cup options, and it is the cup that fixes the 72.626 mm OD and the 25.4 mm assembled width — quote the full HM88648/HM88611AS pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 35.717 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 35.717 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM88648/HM88611AS.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 35.717 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Inch and metric bores collide on paper — 35.717 mm is 1.406 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-HM88648/HM88611AS sets have no seals: a hub or gearbox needs external sealing or the 5,400 r/min grease figure is meaningless once water reaches the cone rib.", "Fit selection follows the rotating ring: a rotating cone on a 35.717 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 72/84.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM88648/HM88611AS; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM88648/HM88611AS?", "a": "4T-HM88648/HM88611AS is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 35.717 mm bore (1.406 in), 72.626 mm outside diameter and 25.4 mm assembled width T (2.859 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 72 kN, C0 84.5 kN, grease limiting speed 5,400 r/min, oil speed 7,200 r/min, mass about 482 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM88648/HM88611AS interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM88648 cone or the HM88611AS cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 72/84.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM88648/HM88611AS and a metric ISO 355 tapered bearing?", "a": "4T-HM88648/HM88611AS follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 35.717×72.626×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM88648/HM88611AS mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM88648/HM88611AS references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM88648/HM88611AS list two speeds, 5,400 and 7,200 r/min?", "a": "The lower figure, 5,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM88648/HM88611AS at 7,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM88648-610", "equiv_brand": "SKF", "level": "partial", "note": "Same 35.717×72.626×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "HM88648-HM88610", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-HM88648 paired with a different cup (HM88610): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm88648-hm88611as", "hm88648-hm88611as", "HM88648-HM88611AS", "4T-HM88648-HM88611AS" ], "locale_variants": {} }, { "sku": "25880-25821", "brand": "NTN", "manufacturer_designation": "NTN 4T-25880/25821", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 35.717, "D_mm": 73.025, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 78.5, "static_load_kN": 85, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7100, "weight_g": 456, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-25880/25821 at 35.717 mm bore (1.406 in), 73.025 mm cup OD and 23.812 mm assembled T, with a grease limiting speed of 5,300 r/min and an oil ceiling of 7,100 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 25880 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 5,300 r/min is the mechanical ceiling for 4T-25880/25821, oil 7,100 r/min with circulating oil — a 1,800 r/min margin at this size. Housing fitment sequence for 4T-25880/25821: press the 25821 cup square into the 73.025 mm seat first, then bring the 25880 cone (on its 35.717 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 35.717 mm cone with an induction heater (max 120 °C) and press the 73.025 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 35.717 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25880/25821.", "The pure-numeric inch family at 35.717 mm bore (73.025×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25880/25821 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 25880 and 25821; use undercut shoulders so the rings seat on the face, not on a radius.", "Open 4T-25880/25821 sets have no seals: a hub or gearbox needs external sealing or the 5,300 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 23.812 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 78.5/85 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25880/25821; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25880/25821?", "a": "4T-25880/25821 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 35.717 mm bore (1.406 in), 73.025 mm outside diameter and 23.812 mm assembled width T (2.875 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 78.5 kN, C0 85 kN, grease limiting speed 5,300 r/min, oil speed 7,100 r/min, mass about 456 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25880/25821 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25880 cone or the 25821 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 78.5/85 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25880/25821 and a metric ISO 355 tapered bearing?", "a": "4T-25880/25821 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 35.717×73.025×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25880/25821 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25880/25821 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25880/25821 list two speeds, 5,300 and 7,100 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25880/25821 at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25880-25820", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25880-25821", "25880-25821", "4T-25880-25821" ], "locale_variants": {} }, { "sku": "339-332", "brand": "NTN", "manufacturer_designation": "NTN 4T-339/332", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 35.717, "D_mm": 80, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 75.5, "static_load_kN": 75, "limiting_speed_rpm": 4700, "max_rpm": 4700, "speed_oil_rpm": 6300, "weight_g": 534, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.406 in (35.717 mm) shaft position as 4T-339/332: cone 339, cup 332, profiled rollers and a pressed-steel cage, rated 75.5 kN basic dynamic and 75 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 339/332 without it. Speed planning uses both catalogue columns: grease 4,700 r/min is the mechanical ceiling for 4T-339/332, oil 6,300 r/min with circulating oil — a 1,600 r/min margin at this size. Cup-side note for 332: within the pure-numeric inch family tables the 339 cone is listed against several cup options, and it is the cup that fixes the 80 mm OD and the 21 mm assembled width — quote the full 339/332 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-339/332, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 35.717 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-339/332.", "The pure-numeric inch family at 35.717 mm bore (80×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 339/332 reference at purchase.", "Never drive the 80 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 35.717×80 mm envelope interchangeable, not the ratings: NTN prints 75.5/75 kN for this execution and another make of the same number can differ in roller complement.", "Fit selection follows the rotating ring: a rotating cone on a 35.717 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 75.5/75 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-339/332; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-339/332?", "a": "4T-339/332 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 35.717 mm bore (1.406 in), 80 mm outside diameter and 21 mm assembled width T (3.15 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 75.5 kN, C0 75 kN, grease limiting speed 4,700 r/min, oil speed 6,300 r/min, mass about 534 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-339/332 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 339 cone or the 332 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 75.5/75 kN ratings change with the cup." }, { "q": "What is the difference between 4T-339/332 and a metric ISO 355 tapered bearing?", "a": "4T-339/332 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 35.717×80×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-339/332 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 339/332 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-339/332 list two speeds, 4,700 and 6,300 r/min?", "a": "The lower figure, 4,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-339/332 at 6,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "339", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-339-332", "339-332", "4T-339-332" ], "locale_variants": {} }, { "sku": "2780-2720", "brand": "NTN", "manufacturer_designation": "NTN 4T-2780/2720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 36.487, "D_mm": 76.2, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 81, "static_load_kN": 90.5, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 516, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 36.487 mm carrying combined radial and thrust load, NTN lists 4T-2780/2720, a single-row 4T tapered roller set of 81 kN C and 90.5 kN C0 inside the 76.2 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 2780 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 5,100 r/min is the mechanical ceiling for 4T-2780/2720, oil 6,800 r/min with circulating oil — a 1,700 r/min margin at this size. Housing fitment sequence for 4T-2780/2720: press the 2720 cup square into the 76.2 mm seat first, then bring the 2780 cone (on its 36.487 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-2780/2720 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 36.487 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2780/2720.", "The pure-numeric inch family at 36.487 mm bore (76.2×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2780/2720 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 2780 and 2720; use undercut shoulders so the rings seat on the face, not on a radius.", "ABMA makes the 36.487×76.2 mm envelope interchangeable, not the ratings: NTN prints 81/90.5 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 2780/2720 pair at ordering: the 2780 cone also ships against sibling cups, and a cup from another reference changes the 23.812 mm assembled width and the rating.", "The 81/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2780/2720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2780/2720?", "a": "4T-2780/2720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 36.487 mm bore (1.436 in), 76.2 mm outside diameter and 23.812 mm assembled width T (3 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 81 kN, C0 90.5 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 516 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2780/2720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2780 cone or the 2720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 81/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2780/2720 and a metric ISO 355 tapered bearing?", "a": "4T-2780/2720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 36.487×76.2×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2780/2720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2780/2720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2780/2720 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2780/2720 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2780", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2780-2720", "2780-2720", "4T-2780-2720" ], "locale_variants": {} }, { "sku": "31597-31520", "brand": "NTN", "manufacturer_designation": "NTN 4T-31597/31520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 36.512, "D_mm": 76.2, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 89.5, "static_load_kN": 97, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 606, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-31597/31520 at 36.512 mm bore (1.437 in), 76.2 mm cup OD and 29.37 mm assembled T, with a grease limiting speed of 5,100 r/min and an oil ceiling of 6,800 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 31597/31520 without it. Selection: C 89.5 kN against C0 97 kN gives a C0/C ratio of 1.08 for the 36.512 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 89.5/97 kN ratings belong to the assembled 31597+31520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 36.512 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 36.512 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-31597/31520.", "The pure-numeric inch family at 36.512 mm bore (76.2×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 31597/31520 reference at purchase.", "An unloaded 4T-31597/31520 near 5,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Quote the full 31597/31520 pair at ordering: the 31597 cone also ships against sibling cups, and a cup from another reference changes the 29.37 mm assembled width and the rating.", "Inch and metric bores collide on paper — 36.512 mm is 1.437 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 89.5/97 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-31597/31520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-31597/31520?", "a": "4T-31597/31520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 36.512 mm bore (1.437 in), 76.2 mm outside diameter and 29.37 mm assembled width T (3 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 89.5 kN, C0 97 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 606 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-31597/31520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 31597 cone or the 31520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 89.5/97 kN ratings change with the cup." }, { "q": "What is the difference between 4T-31597/31520 and a metric ISO 355 tapered bearing?", "a": "4T-31597/31520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 36.512×76.2×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-31597/31520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 31597/31520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-31597/31520 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-31597/31520 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "31597", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-31597-31520", "31597-31520", "4T-31597-31520" ], "locale_variants": {} }, { "sku": "HM89448-HM89410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM89448/HM89410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 36.512, "D_mm": 76.2, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 105, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 628, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 36.512 mm carrying combined radial and thrust load, NTN lists 4T-HM89448/HM89410, a single-row 4T tapered roller set of 86.5 kN C and 105 kN C0 inside the 76.2 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HM89448 sits in the heavy-medium HM family. Speed planning uses both catalogue columns: grease 5,100 r/min is the mechanical ceiling for 4T-HM89448/HM89410, oil 6,800 r/min with circulating oil — a 1,700 r/min margin at this size. Housing fitment sequence for 4T-HM89448/HM89410: press the HM89410 cup square into the 76.2 mm seat first, then bring the HM89448 cone (on its 36.512 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-HM89448/HM89410, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 36.512 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM89448/HM89410.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 36.512 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Grease packs must leave free volume inside the 29.37 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,800 r/min raises temperature and destroys the setting.", "Replacing one half of an adjusted pair without resetting end play negates the 29.37 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never drive the 76.2 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 86.5/105 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM89448/HM89410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM89448/HM89410?", "a": "4T-HM89448/HM89410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 36.512 mm bore (1.437 in), 76.2 mm outside diameter and 29.37 mm assembled width T (3 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 105 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 628 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM89448/HM89410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM89448 cone or the HM89410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/105 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM89448/HM89410 and a metric ISO 355 tapered bearing?", "a": "4T-HM89448/HM89410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 36.512×76.2×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM89448/HM89410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM89448/HM89410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM89448/HM89410 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM89448/HM89410 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM89448", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm89448-hm89410", "hm89448-hm89410", "HM89448-HM89410", "4T-HM89448-HM89410" ], "locale_variants": {} }, { "sku": "HM89449-HM89411", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM89449/HM89411", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 36.512, "D_mm": 76.2, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 105, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 630, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-HM89449/HM89411 denotes the heavy-medium HM family of NTN inch tapered roller bearings — cone HM89449 and cup HM89411 delivered as a matched, separable pair of 36.512 mm bore and 76.2 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HM89449 identifies the cone of 36.512 mm (1.437 in) bore by catalogue lookup, and HM89411 fixes the 76.2 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 29.37 mm T of each 4T-HM89449/HM89411 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 86.5/105 kN ratings belong to the assembled HM89449+HM89411 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-HM89449/HM89411; reverse the fit logic when the cup rotates.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 36.512 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM89449/HM89411.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 36.512 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Shaft and housing fillets must clear the ring chamfers of HM89449 and HM89411; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 29.37 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,800 r/min raises temperature and destroys the setting.", "Do not confuse T (29.37 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 86.5/105 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM89449/HM89411; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM89449/HM89411?", "a": "4T-HM89449/HM89411 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 36.512 mm bore (1.437 in), 76.2 mm outside diameter and 29.37 mm assembled width T (3 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 105 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 630 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM89449/HM89411 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM89449 cone or the HM89411 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/105 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM89449/HM89411 and a metric ISO 355 tapered bearing?", "a": "4T-HM89449/HM89411 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 36.512×76.2×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM89449/HM89411 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM89449/HM89411 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM89449/HM89411 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM89449/HM89411 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM89449-410", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm89449-hm89411", "hm89449-hm89411", "HM89449-HM89411", "4T-HM89449-HM89411" ], "locale_variants": {} }, { "sku": "3479-3420", "brand": "NTN", "manufacturer_designation": "NTN 4T-3479/3420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 36.512, "D_mm": 79.375, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 103, "static_load_kN": 114, "limiting_speed_rpm": 4900, "max_rpm": 4900, "speed_oil_rpm": 6600, "weight_g": 707, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3479/3420 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 36.512×79.375×29.37 mm (assembled width T), for a shaft of about 36.512 mm (1.437 in). Reading the designation: 4T-3479/3420 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Contact-angle geometry of the pure-numeric inch family gives 4T-3479/3420 its radial/axial load split — at 103/114 kN the static rating is about 1.11× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 3420: within the pure-numeric inch family tables the 3479 cone is listed against several cup options, and it is the cup that fixes the 79.375 mm OD and the 29.37 mm assembled width — quote the full 3479/3420 pair, never the cone alone. Running clearance of 4T-3479/3420 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 36.512 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3479/3420.", "The pure-numeric inch family at 36.512 mm bore (79.375×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3479/3420 reference at purchase.", "ABMA makes the 36.512×79.375 mm envelope interchangeable, not the ratings: NTN prints 103/114 kN for this execution and another make of the same number can differ in roller complement.", "Shaft and housing fillets must clear the ring chamfers of 3479 and 3420; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 36.512 mm is 1.437 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 103/114 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3479/3420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3479/3420?", "a": "4T-3479/3420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 36.512 mm bore (1.437 in), 79.375 mm outside diameter and 29.37 mm assembled width T (3.125 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 103 kN, C0 114 kN, grease limiting speed 4,900 r/min, oil speed 6,600 r/min, mass about 707 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3479/3420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3479 cone or the 3420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 103/114 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3479/3420 and a metric ISO 355 tapered bearing?", "a": "4T-3479/3420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 36.512×79.375×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3479/3420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3479/3420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3479/3420 list two speeds, 4,900 and 6,600 r/min?", "a": "The lower figure, 4,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3479/3420 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3479", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3479-3420", "3479-3420", "4T-3479-3420" ], "locale_variants": {} }, { "sku": "HM89249-HM89210", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM89249/HM89210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 36.512, "D_mm": 79.375, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 95.5, "static_load_kN": 104, "limiting_speed_rpm": 5000, "max_rpm": 5000, "speed_oil_rpm": 6600, "weight_g": 689, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-HM89249/HM89210 denotes the heavy-medium HM family of NTN inch tapered roller bearings — cone HM89249 and cup HM89210 delivered as a matched, separable pair of 36.512 mm bore and 79.375 mm outside diameter. Cone and cup of 4T-HM89249/HM89210 are separately stocked parts: a worn HM89210 cup can be replaced against the existing HM89249 cone, provided the new cup carries the identical reference — pairing across references changes the 29.37 mm assembled width and the rating. Selection: C 95.5 kN against C0 104 kN gives a C0/C ratio of 1.09 for the 36.512 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for HM89210: within the heavy-medium HM family tables the HM89249 cone is listed against several cup options, and it is the cup that fixes the 79.375 mm OD and the 29.37 mm assembled width — quote the full HM89249/HM89210 pair, never the cone alone. Fillet radii must clear the chamfers of the HM89249 cone and HM89210 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 36.512 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM89249/HM89210.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 36.512 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Quote the full HM89249/HM89210 pair at ordering: the HM89249 cone also ships against sibling cups, and a cup from another reference changes the 29.37 mm assembled width and the rating.", "Replacing one half of an adjusted pair without resetting end play negates the 29.37 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ABMA makes the 36.512×79.375 mm envelope interchangeable, not the ratings: NTN prints 95.5/104 kN for this execution and another make of the same number can differ in roller complement.", "The 95.5/104 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM89249/HM89210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM89249/HM89210?", "a": "4T-HM89249/HM89210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 36.512 mm bore (1.437 in), 79.375 mm outside diameter and 29.37 mm assembled width T (3.125 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 95.5 kN, C0 104 kN, grease limiting speed 5,000 r/min, oil speed 6,600 r/min, mass about 689 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM89249/HM89210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM89249 cone or the HM89210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 95.5/104 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM89249/HM89210 and a metric ISO 355 tapered bearing?", "a": "4T-HM89249/HM89210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 36.512×79.375×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM89249/HM89210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM89249/HM89210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM89249/HM89210 list two speeds, 5,000 and 6,600 r/min?", "a": "The lower figure, 5,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM89249/HM89210 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM89249", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm89249-hm89210", "hm89249-hm89210", "HM89249-HM89210", "4T-HM89249-HM89210" ], "locale_variants": {} }, { "sku": "44143-44348", "brand": "NTN", "manufacturer_designation": "NTN 4T-44143/44348", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 36.512, "D_mm": 88.5, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 78.5, "static_load_kN": 78, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 730, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-44143/44348 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 36.512×88.5×25.4 mm (assembled width T), for a shaft of about 36.512 mm (1.437 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 44143 sits in the pure-numeric inch family. Grease relubrication at the 4,000 r/min limiting speed targets the cone-rib contact; sustaining 5,300 r/min needs an oil supply directed at the large roller ends. Cup-side note for 44348: within the pure-numeric inch family tables the 44143 cone is listed against several cup options, and it is the cup that fixes the 88.5 mm OD and the 25.4 mm assembled width — quote the full 44143/44348 pair, never the cone alone. Running clearance of 4T-44143/44348 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 36.512 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-44143/44348.", "The pure-numeric inch family at 36.512 mm bore (88.5×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 44143/44348 reference at purchase.", "Quote the full 44143/44348 pair at ordering: the 44143 cone also ships against sibling cups, and a cup from another reference changes the 25.4 mm assembled width and the rating.", "An unloaded 4T-44143/44348 near 4,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 25.4 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 78.5/78 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-44143/44348; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-44143/44348?", "a": "4T-44143/44348 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 36.512 mm bore (1.437 in), 88.5 mm outside diameter and 25.4 mm assembled width T (3.484 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 78.5 kN, C0 78 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 730 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-44143/44348 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 44143 cone or the 44348 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 78.5/78 kN ratings change with the cup." }, { "q": "What is the difference between 4T-44143/44348 and a metric ISO 355 tapered bearing?", "a": "4T-44143/44348 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 36.512×88.5×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-44143/44348 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 44143/44348 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-44143/44348 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-44143/44348 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "44143", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-44143-44348", "44143-44348", "4T-44143-44348" ], "locale_variants": {} }, { "sku": "JL69349-JL69310", "brand": "NTN", "manufacturer_designation": "NTN 4T-JL69349/JL69310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38, "D_mm": 63, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 43, "static_load_kN": 52.5, "limiting_speed_rpm": 5700, "max_rpm": 5700, "speed_oil_rpm": 7600, "weight_g": 200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JL69349/JL69310 is the NTN 4T catalogue entry for a 38×63×17 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: JL69349 identifies the cone of 38 mm (1.496 in) bore by catalogue lookup, and JL69310 fixes the 63 mm OD. The 1.1 kN of dynamic capacity per millimetre of bore summarises the 43 kN rating over the 38 mm bore — sanity-check any interchange candidate against this ratio and the 17 mm T. Cup-side note for JL69310: within the JL prefixed family tables the JL69349 cone is listed against several cup options, and it is the cup that fixes the 63 mm OD and the 17 mm assembled width — quote the full JL69349/JL69310 pair, never the cone alone. Running clearance of 4T-JL69349/JL69310 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 38 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-JL69349/JL69310.", "The J-prefixed JL69349 code belongs to a metric-envelope inch family: its 38 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Open 4T-JL69349/JL69310 sets have no seals: a hub or gearbox needs external sealing or the 5,700 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 38×63 mm envelope interchangeable, not the ratings: NTN prints 43/52.5 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full JL69349/JL69310 pair at ordering: the JL69349 cone also ships against sibling cups, and a cup from another reference changes the 17 mm assembled width and the rating.", "The 43/52.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JL69349/JL69310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JL69349/JL69310?", "a": "4T-JL69349/JL69310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38 mm bore (1.496 in), 63 mm outside diameter and 17 mm assembled width T (2.48 × 0.669 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 43 kN, C0 52.5 kN, grease limiting speed 5,700 r/min, oil speed 7,600 r/min, mass about 200 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JL69349/JL69310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JL69349 cone or the JL69310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 43/52.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JL69349/JL69310 and a metric ISO 355 tapered bearing?", "a": "4T-JL69349/JL69310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38×63×17 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JL69349/JL69310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JL69349/JL69310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JL69349/JL69310 list two speeds, 5,700 and 7,600 r/min?", "a": "The lower figure, 5,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JL69349/JL69310 at 7,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JL69349", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jl69349-jl69310", "4t-jl69349-jl69310", "jl69349-jl69310", "JL69349-JL69310", "4T-JL69349-JL69310" ], "locale_variants": {} }, { "sku": "13889-13830", "brand": "NTN", "manufacturer_designation": "NTN 4T-13889/13830", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 63.5, "B_mm": 12.7, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 28.7, "static_load_kN": 33.5, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7300, "weight_g": 148, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-13889/13830 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 38.1×63.5×12.7 mm (assembled width T), for a shaft of about 38.1 mm (1.5 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 13889 identifies the cone of 38.1 mm (1.5 in) bore by catalogue lookup, and 13830 fixes the 63.5 mm OD. Grease relubrication at the 5,500 r/min limiting speed targets the cone-rib contact; sustaining 7,300 r/min needs an oil supply directed at the large roller ends. Cup-side note for 13830: within the pure-numeric inch family tables the 13889 cone is listed against several cup options, and it is the cup that fixes the 63.5 mm OD and the 12.7 mm assembled width — quote the full 13889/13830 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-13889/13830 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-13889/13830.", "The pure-numeric inch family at 38.1 mm bore (63.5×12.7 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 13889/13830 reference at purchase.", "Quote the full 13889/13830 pair at ordering: the 13889 cone also ships against sibling cups, and a cup from another reference changes the 12.7 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of 13889 and 13830; use undercut shoulders so the rings seat on the face, not on a radius.", "Do not confuse T (12.7 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 28.7/33.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-13889/13830; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-13889/13830?", "a": "4T-13889/13830 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 63.5 mm outside diameter and 12.7 mm assembled width T (2.5 × 0.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 28.7 kN, C0 33.5 kN, grease limiting speed 5,500 r/min, oil speed 7,300 r/min, mass about 148 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-13889/13830 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 13889 cone or the 13830 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 28.7/33.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-13889/13830 and a metric ISO 355 tapered bearing?", "a": "4T-13889/13830 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×63.5×12.7 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-13889/13830 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 13889/13830 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-13889/13830 list two speeds, 5,500 and 7,300 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-13889/13830 at 7,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "13889", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-13889-13830", "13889-13830", "4T-13889-13830" ], "locale_variants": {} }, { "sku": "LM29748-LM29710", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM29748/LM29710", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 65.088, "B_mm": 18.034, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 48, "static_load_kN": 57, "limiting_speed_rpm": 5500, "max_rpm": 5500, "speed_oil_rpm": 7400, "weight_g": 227, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-LM29748/LM29710 at 38.1 mm bore (1.5 in), 65.088 mm cup OD and 18.034 mm assembled T, with a grease limiting speed of 5,500 r/min and an oil ceiling of 7,400 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — LM29748 sits in the light-medium LM family. The 13.5 mm radial section over the 38.1 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for LM29710: within the light-medium LM family tables the LM29748 cone is listed against several cup options, and it is the cup that fixes the 65.088 mm OD and the 18.034 mm assembled width — quote the full LM29748/LM29710 pair, never the cone alone. Fillet radii must clear the chamfers of the LM29748 cone and LM29710 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM29748/LM29710.", "The light-medium LM family at 38.1 mm bore (65.088×18.034 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM29748/LM29710 reference at purchase.", "Open 4T-LM29748/LM29710 sets have no seals: a hub or gearbox needs external sealing or the 5,500 r/min grease figure is meaningless once water reaches the cone rib.", "Inch and metric bores collide on paper — 38.1 mm is 1.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Inch and metric bores collide on paper — 38.1 mm is 1.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 48/57 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM29748/LM29710; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM29748/LM29710?", "a": "4T-LM29748/LM29710 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 65.088 mm outside diameter and 18.034 mm assembled width T (2.563 × 0.71 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 48 kN, C0 57 kN, grease limiting speed 5,500 r/min, oil speed 7,400 r/min, mass about 227 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM29748/LM29710 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM29748 cone or the LM29710 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 48/57 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM29748/LM29710 and a metric ISO 355 tapered bearing?", "a": "4T-LM29748/LM29710 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×65.088×18.034 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM29748/LM29710 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM29748/LM29710 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM29748/LM29710 list two speeds, 5,500 and 7,400 r/min?", "a": "The lower figure, 5,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM29748/LM29710 at 7,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM29748-710", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm29748-lm29710", "lm29748-lm29710", "LM29748-LM29710", "4T-LM29748-LM29710" ], "locale_variants": {} }, { "sku": "13685-13621", "brand": "NTN", "manufacturer_designation": "NTN 4T-13685/13621", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 69.012, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53, "static_load_kN": 59.5, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7100, "weight_g": 294, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-13685/13621 at 38.1 mm bore (1.5 in), 69.012 mm cup OD and 19.05 mm assembled T, with a grease limiting speed of 5,300 r/min and an oil ceiling of 7,100 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 13685 sits in the pure-numeric inch family. The 1.4 kN of dynamic capacity per millimetre of bore summarises the 53 kN rating over the 38.1 mm bore — sanity-check any interchange candidate against this ratio and the 19.05 mm T. The printed 53/59.5 kN ratings belong to the assembled 13685+13621 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-13685/13621 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-13685/13621.", "The pure-numeric inch family at 38.1 mm bore (69.012×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 13685/13621 reference at purchase.", "An unloaded 4T-13685/13621 near 5,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 38.1 mm is 1.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Replacing one half of an adjusted pair without resetting end play negates the 19.05 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 53/59.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-13685/13621; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-13685/13621?", "a": "4T-13685/13621 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 69.012 mm outside diameter and 19.05 mm assembled width T (2.717 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53 kN, C0 59.5 kN, grease limiting speed 5,300 r/min, oil speed 7,100 r/min, mass about 294 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-13685/13621 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 13685 cone or the 13621 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53/59.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-13685/13621 and a metric ISO 355 tapered bearing?", "a": "4T-13685/13621 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×69.012×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-13685/13621 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 13685/13621 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-13685/13621 list two speeds, 5,300 and 7,100 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-13685/13621 at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "13685", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-13685-13621", "13685-13621", "4T-13685-13621" ], "locale_variants": {} }, { "sku": "13687-13621", "brand": "NTN", "manufacturer_designation": "NTN 4T-13687/13621", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 69.012, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53, "static_load_kN": 59.5, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7100, "weight_g": 296, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-13687/13621 at 38.1 mm bore (1.5 in), 69.012 mm cup OD and 19.05 mm assembled T, with a grease limiting speed of 5,300 r/min and an oil ceiling of 7,100 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 13687/13621 without it. Selection: C 53 kN against C0 59.5 kN gives a C0/C ratio of 1.12 for the 38.1 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 53/59.5 kN ratings belong to the assembled 13687+13621 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 13687 cone and 13621 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-13687/13621.", "The pure-numeric inch family at 38.1 mm bore (69.012×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 13687/13621 reference at purchase.", "Grease packs must leave free volume inside the 19.05 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,100 r/min raises temperature and destroys the setting.", "Open 4T-13687/13621 sets have no seals: a hub or gearbox needs external sealing or the 5,300 r/min grease figure is meaningless once water reaches the cone rib.", "An unloaded 4T-13687/13621 near 5,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 53/59.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-13687/13621; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-13687/13621?", "a": "4T-13687/13621 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 69.012 mm outside diameter and 19.05 mm assembled width T (2.717 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53 kN, C0 59.5 kN, grease limiting speed 5,300 r/min, oil speed 7,100 r/min, mass about 296 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-13687/13621 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 13687 cone or the 13621 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53/59.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-13687/13621 and a metric ISO 355 tapered bearing?", "a": "4T-13687/13621 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×69.012×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-13687/13621 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 13687/13621 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-13687/13621 list two speeds, 5,300 and 7,100 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-13687/13621 at 7,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "13687", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-13687-13621", "13687-13621", "4T-13687-13621" ], "locale_variants": {} }, { "sku": "19150-19281", "brand": "NTN", "manufacturer_designation": "NTN 4T-19150/19281", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 71.438, "B_mm": 15.875, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 48, "static_load_kN": 51, "limiting_speed_rpm": 5400, "max_rpm": 5400, "speed_oil_rpm": 7200, "weight_g": 241, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 38.1 mm carrying combined radial and thrust load, NTN lists 4T-19150/19281, a single-row 4T tapered roller set of 48 kN C and 51 kN C0 inside the 71.438 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 19150/19281 without it. Imperial cross-check for the drawing: 38.1×71.438×15.875 mm converts to 1.5 × 2.813 × 0.625 in; the ABMA envelope swaps with like-numbered inch parts but the 48/51 kN ratings are NTN-specific. The printed 48/51 kN ratings belong to the assembled 19150+19281 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 38.1 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-19150/19281.", "The pure-numeric inch family at 38.1 mm bore (71.438×15.875 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 19150/19281 reference at purchase.", "Quote the full 19150/19281 pair at ordering: the 19150 cone also ships against sibling cups, and a cup from another reference changes the 15.875 mm assembled width and the rating.", "Grease packs must leave free volume inside the 15.875 mm-wide set; over-greasing a pair churning near the oil-band speed of 7,200 r/min raises temperature and destroys the setting.", "Open 4T-19150/19281 sets have no seals: a hub or gearbox needs external sealing or the 5,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 48/51 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-19150/19281; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-19150/19281?", "a": "4T-19150/19281 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 71.438 mm outside diameter and 15.875 mm assembled width T (2.813 × 0.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 48 kN, C0 51 kN, grease limiting speed 5,400 r/min, oil speed 7,200 r/min, mass about 241 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-19150/19281 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 19150 cone or the 19281 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 48/51 kN ratings change with the cup." }, { "q": "What is the difference between 4T-19150/19281 and a metric ISO 355 tapered bearing?", "a": "4T-19150/19281 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×71.438×15.875 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-19150/19281 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 19150/19281 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-19150/19281 list two speeds, 5,400 and 7,200 r/min?", "a": "The lower figure, 5,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-19150/19281 at 7,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "19150", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-19150-19281", "19150-19281", "4T-19150-19281" ], "locale_variants": {} }, { "sku": "16150-16282", "brand": "NTN", "manufacturer_designation": "NTN 4T-16150/16282", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 72, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 53, "static_load_kN": 58.5, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7000, "weight_g": 331, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-16150/16282 is the NTN 4T catalogue entry for a 38.1×72×19 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 16150 sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 19 mm T of each 4T-16150/16282 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-16150/16282: press the 16282 cup square into the 72 mm seat first, then bring the 16150 cone (on its 38.1 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-16150/16282 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-16150/16282.", "The pure-numeric inch family at 38.1 mm bore (72×19 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 16150/16282 reference at purchase.", "Inch and metric bores collide on paper — 38.1 mm is 1.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Quote the full 16150/16282 pair at ordering: the 16150 cone also ships against sibling cups, and a cup from another reference changes the 19 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 38.1 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 53/58.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-16150/16282; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-16150/16282?", "a": "4T-16150/16282 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 72 mm outside diameter and 19 mm assembled width T (2.835 × 0.748 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53 kN, C0 58.5 kN, grease limiting speed 5,300 r/min, oil speed 7,000 r/min, mass about 331 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-16150/16282 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 16150 cone or the 16282 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 53/58.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-16150/16282 and a metric ISO 355 tapered bearing?", "a": "4T-16150/16282 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×72×19 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-16150/16282 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 16150/16282 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-16150/16282 list two speeds, 5,300 and 7,000 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-16150/16282 at 7,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "16150-16283", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "16150-16284", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=179", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-16150-16282", "16150-16282", "4T-16150-16282" ], "locale_variants": {} }, { "sku": "2776-2720", "brand": "NTN", "manufacturer_designation": "NTN 4T-2776/2720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 76.2, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 81, "static_load_kN": 90.5, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 495, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-2776/2720 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 38.1×76.2×23.812 mm (assembled width T), for a shaft of about 38.1 mm (1.5 in). Reading the designation: 4T-2776/2720 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 19.1 mm radial section over the 38.1 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-2776/2720: press the 2720 cup square into the 76.2 mm seat first, then bring the 2776 cone (on its 38.1 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-2776/2720 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2776/2720.", "The pure-numeric inch family at 38.1 mm bore (76.2×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2776/2720 reference at purchase.", "Grease packs must leave free volume inside the 23.812 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,800 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 38.1 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 81/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2776/2720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2776/2720?", "a": "4T-2776/2720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 76.2 mm outside diameter and 23.812 mm assembled width T (3 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 81 kN, C0 90.5 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 495 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2776/2720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2776 cone or the 2720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 81/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2776/2720 and a metric ISO 355 tapered bearing?", "a": "4T-2776/2720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×76.2×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2776/2720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2776/2720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2776/2720 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2776/2720 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2776", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2776-2720", "2776-2720", "4T-2776-2720" ], "locale_variants": {} }, { "sku": "2788-2720-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-2788/2720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 76.2, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 81, "static_load_kN": 90.5, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 494, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 38.1 mm carrying combined radial and thrust load, NTN lists 4T-2788/2720, a single-row 4T tapered roller set of 81 kN C and 90.5 kN C0 inside the 76.2 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 2788 sits in the pure-numeric inch family. Selection: C 81 kN against C0 90.5 kN gives a C0/C ratio of 1.12 for the 38.1 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 2720: within the pure-numeric inch family tables the 2788 cone is listed against several cup options, and it is the cup that fixes the 76.2 mm OD and the 23.812 mm assembled width — quote the full 2788/2720 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-2788/2720; reverse the fit logic when the cup rotates.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2788/2720.", "The pure-numeric inch family at 38.1 mm bore (76.2×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2788/2720 reference at purchase.", "An unloaded 4T-2788/2720 near 5,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Quote the full 2788/2720 pair at ordering: the 2788 cone also ships against sibling cups, and a cup from another reference changes the 23.812 mm assembled width and the rating.", "Never drive the 76.2 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 81/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2788/2720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2788/2720?", "a": "4T-2788/2720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 76.2 mm outside diameter and 23.812 mm assembled width T (3 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 81 kN, C0 90.5 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 494 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2788/2720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2788 cone or the 2720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 81/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2788/2720 and a metric ISO 355 tapered bearing?", "a": "4T-2788/2720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×76.2×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2788/2720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2788/2720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2788/2720 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2788/2720 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2788-2720", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.1×76.2×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2788-2720", "2788-2720", "4T-2788-2720", "2788-2720-NTN" ], "locale_variants": {} }, { "sku": "28150-28300", "brand": "NTN", "manufacturer_designation": "NTN 4T-28150/28300", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 76.2, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 61.5, "static_load_kN": 63, "limiting_speed_rpm": 5000, "max_rpm": 5000, "speed_oil_rpm": 6700, "weight_g": 406, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-28150/28300 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 38.1×76.2×20.638 mm (assembled width T), for a shaft of about 38.1 mm (1.5 in). Cone and cup of 4T-28150/28300 are separately stocked parts: a worn 28300 cup can be replaced against the existing 28150 cone, provided the new cup carries the identical reference — pairing across references changes the 20.638 mm assembled width and the rating. The 1.6 kN of dynamic capacity per millimetre of bore summarises the 61.5 kN rating over the 38.1 mm bore — sanity-check any interchange candidate against this ratio and the 20.638 mm T. Housing fitment sequence for 4T-28150/28300: press the 28300 cup square into the 76.2 mm seat first, then bring the 28150 cone (on its 38.1 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-28150/28300 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-28150/28300.", "The pure-numeric inch family at 38.1 mm bore (76.2×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28150/28300 reference at purchase.", "Inch and metric bores collide on paper — 38.1 mm is 1.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Quote the full 28150/28300 pair at ordering: the 28150 cone also ships against sibling cups, and a cup from another reference changes the 20.638 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 38.1 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 61.5/63 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28150/28300; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28150/28300?", "a": "4T-28150/28300 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 76.2 mm outside diameter and 20.638 mm assembled width T (3 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 61.5 kN, C0 63 kN, grease limiting speed 5,000 r/min, oil speed 6,700 r/min, mass about 406 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28150/28300 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28150 cone or the 28300 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 61.5/63 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28150/28300 and a metric ISO 355 tapered bearing?", "a": "4T-28150/28300 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×76.2×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28150/28300 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28150/28300 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28150/28300 list two speeds, 5,000 and 6,700 r/min?", "a": "The lower figure, 5,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28150/28300 at 6,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28150-28315", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-28150 paired with a different cup (28315): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28150-28300", "28150-28300", "4T-28150-28300" ], "locale_variants": {} }, { "sku": "26878-26822", "brand": "NTN", "manufacturer_designation": "NTN 4T-26878/26822", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 79.375, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 97.5, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 575, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.5 in (38.1 mm) shaft position as 4T-26878/26822: cone 26878, cup 26822, profiled rollers and a pressed-steel cage, rated 85 kN basic dynamic and 97.5 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 26878/26822 without it. Imperial cross-check for the drawing: 38.1×79.375×23.812 mm converts to 1.5 × 3.125 × 0.937 in; the ABMA envelope swaps with like-numbered inch parts but the 85/97.5 kN ratings are NTN-specific. Cup-side note for 26822: within the pure-numeric inch family tables the 26878 cone is listed against several cup options, and it is the cup that fixes the 79.375 mm OD and the 23.812 mm assembled width — quote the full 26878/26822 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-26878/26822 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-26878/26822.", "The pure-numeric inch family at 38.1 mm bore (79.375×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 26878/26822 reference at purchase.", "ABMA makes the 38.1×79.375 mm envelope interchangeable, not the ratings: NTN prints 85/97.5 kN for this execution and another make of the same number can differ in roller complement.", "Fit selection follows the rotating ring: a rotating cone on a 38.1 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 26878/26822 pair at ordering: the 26878 cone also ships against sibling cups, and a cup from another reference changes the 23.812 mm assembled width and the rating.", "The 85/97.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-26878/26822; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-26878/26822?", "a": "4T-26878/26822 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 79.375 mm outside diameter and 23.812 mm assembled width T (3.125 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 97.5 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 575 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-26878/26822 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 26878 cone or the 26822 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/97.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-26878/26822 and a metric ISO 355 tapered bearing?", "a": "4T-26878/26822 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×79.375×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-26878/26822 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 26878/26822 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-26878/26822 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-26878/26822 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "26878", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-26878-26822", "26878-26822", "4T-26878-26822" ], "locale_variants": {} }, { "sku": "3490-3420-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-3490/3420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 79.375, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 103, "static_load_kN": 114, "limiting_speed_rpm": 4900, "max_rpm": 4900, "speed_oil_rpm": 6600, "weight_g": 688, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-3490/3420 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 3490 and cup 3420 delivered as a matched, separable pair of 38.1 mm bore and 79.375 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 3490 sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 29.37 mm T of each 4T-3490/3420 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 3420: within the pure-numeric inch family tables the 3490 cone is listed against several cup options, and it is the cup that fixes the 79.375 mm OD and the 29.37 mm assembled width — quote the full 3490/3420 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-3490/3420 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3490/3420.", "The pure-numeric inch family at 38.1 mm bore (79.375×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3490/3420 reference at purchase.", "Quote the full 3490/3420 pair at ordering: the 3490 cone also ships against sibling cups, and a cup from another reference changes the 29.37 mm assembled width and the rating.", "Grease packs must leave free volume inside the 29.37 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,600 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 38.1 mm is 1.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 103/114 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3490/3420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3490/3420?", "a": "4T-3490/3420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 79.375 mm outside diameter and 29.37 mm assembled width T (3.125 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 103 kN, C0 114 kN, grease limiting speed 4,900 r/min, oil speed 6,600 r/min, mass about 688 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3490/3420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3490 cone or the 3420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 103/114 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3490/3420 and a metric ISO 355 tapered bearing?", "a": "4T-3490/3420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×79.375×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3490/3420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3490/3420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3490/3420 list two speeds, 4,900 and 6,600 r/min?", "a": "The lower figure, 4,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3490/3420 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3490-3420", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3490-3420", "3490-3420", "4T-3490-3420", "3490-3420-NTN" ], "locale_variants": {} }, { "sku": "28150-28315", "brand": "NTN", "manufacturer_designation": "NTN 4T-28150/28315", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 80, "B_mm": 21.006, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 61.5, "static_load_kN": 63, "limiting_speed_rpm": 5000, "max_rpm": 5000, "speed_oil_rpm": 6700, "weight_g": 467, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-28150/28315 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 28150 and cup 28315 delivered as a matched, separable pair of 38.1 mm bore and 80 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 28150/28315 without it. The 1.6 kN of dynamic capacity per millimetre of bore summarises the 61.5 kN rating over the 38.1 mm bore — sanity-check any interchange candidate against this ratio and the 21.006 mm T. Housing fitment sequence for 4T-28150/28315: press the 28315 cup square into the 80 mm seat first, then bring the 28150 cone (on its 38.1 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-28150/28315 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-28150/28315.", "The pure-numeric inch family at 38.1 mm bore (80×21.006 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28150/28315 reference at purchase.", "Grease packs must leave free volume inside the 21.006 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,700 r/min raises temperature and destroys the setting.", "Do not confuse T (21.006 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Do not confuse T (21.006 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 61.5/63 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28150/28315; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28150/28315?", "a": "4T-28150/28315 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 80 mm outside diameter and 21.006 mm assembled width T (3.15 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 61.5 kN, C0 63 kN, grease limiting speed 5,000 r/min, oil speed 6,700 r/min, mass about 467 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28150/28315 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28150 cone or the 28315 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 61.5/63 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28150/28315 and a metric ISO 355 tapered bearing?", "a": "4T-28150/28315 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×80×21.006 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28150/28315 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28150/28315 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28150/28315 list two speeds, 5,000 and 6,700 r/min?", "a": "The lower figure, 5,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28150/28315 at 6,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28150-28300", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-28150 paired with a different cup (28300): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28150-28315", "28150-28315", "4T-28150-28315" ], "locale_variants": {} }, { "sku": "27880-27820", "brand": "NTN", "manufacturer_designation": "NTN 4T-27880/27820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 80.035, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 74.5, "static_load_kN": 82.5, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 567, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.5 in (38.1 mm) shaft position as 4T-27880/27820: cone 27880, cup 27820, profiled rollers and a pressed-steel cage, rated 74.5 kN basic dynamic and 82.5 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 27880/27820 without it. The 21.0 mm radial section over the 38.1 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 27820: within the pure-numeric inch family tables the 27880 cone is listed against several cup options, and it is the cup that fixes the 80.035 mm OD and the 24.608 mm assembled width — quote the full 27880/27820 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-27880/27820; reverse the fit logic when the cup rotates.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-27880/27820.", "The pure-numeric inch family at 38.1 mm bore (80.035×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 27880/27820 reference at purchase.", "Quote the full 27880/27820 pair at ordering: the 27880 cone also ships against sibling cups, and a cup from another reference changes the 24.608 mm assembled width and the rating.", "Do not confuse T (24.608 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-27880/27820 sets have no seals: a hub or gearbox needs external sealing or the 4,800 r/min grease figure is meaningless once water reaches the cone rib.", "The 74.5/82.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-27880/27820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-27880/27820?", "a": "4T-27880/27820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 80.035 mm outside diameter and 24.608 mm assembled width T (3.151 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 74.5 kN, C0 82.5 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 567 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-27880/27820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 27880 cone or the 27820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 74.5/82.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-27880/27820 and a metric ISO 355 tapered bearing?", "a": "4T-27880/27820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×80.035×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-27880/27820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 27880/27820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-27880/27820 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-27880/27820 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "27880", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-27880-27820", "27880-27820", "4T-27880-27820" ], "locale_variants": {} }, { "sku": "HM801346-HM801310", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM801346/HM801310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 82.55, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 96.5, "static_load_kN": 117, "limiting_speed_rpm": 4700, "max_rpm": 4700, "speed_oil_rpm": 6200, "weight_g": 767, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.5 in (38.1 mm) shaft position as 4T-HM801346/HM801310: cone HM801346, cup HM801310, profiled rollers and a pressed-steel cage, rated 96.5 kN basic dynamic and 117 kN static. Cone and cup of 4T-HM801346/HM801310 are separately stocked parts: a worn HM801310 cup can be replaced against the existing HM801346 cone, provided the new cup carries the identical reference — pairing across references changes the 29.37 mm assembled width and the rating. Grease relubrication at the 4,700 r/min limiting speed targets the cone-rib contact; sustaining 6,200 r/min needs an oil supply directed at the large roller ends. The printed 96.5/117 kN ratings belong to the assembled HM801346+HM801310 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-HM801346/HM801310 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM801346/HM801310.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 38.1 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Never drive the 82.55 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 38.1×82.55 mm envelope interchangeable, not the ratings: NTN prints 96.5/117 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-HM801346/HM801310 near 4,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 96.5/117 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM801346/HM801310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM801346/HM801310?", "a": "4T-HM801346/HM801310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 82.55 mm outside diameter and 29.37 mm assembled width T (3.25 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 96.5 kN, C0 117 kN, grease limiting speed 4,700 r/min, oil speed 6,200 r/min, mass about 767 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM801346/HM801310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM801346 cone or the HM801310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 96.5/117 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM801346/HM801310 and a metric ISO 355 tapered bearing?", "a": "4T-HM801346/HM801310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×82.55×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM801346/HM801310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM801346/HM801310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM801346/HM801310 list two speeds, 4,700 and 6,200 r/min?", "a": "The lower figure, 4,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM801346/HM801310 at 6,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM801346-310", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm801346-hm801310", "hm801346-hm801310", "HM801346-HM801310", "4T-HM801346-HM801310" ], "locale_variants": {} }, { "sku": "25572-25520-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-25572/25520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 84.5, "static_load_kN": 98, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 646, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-25572/25520 is the NTN 4T catalogue entry for a 38.1×82.931×23.812 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 25572/25520 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 23.812 mm T of each 4T-25572/25520 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 25520: within the pure-numeric inch family tables the 25572 cone is listed against several cup options, and it is the cup that fixes the 82.931 mm OD and the 23.812 mm assembled width — quote the full 25572/25520 pair, never the cone alone. Fillet radii must clear the chamfers of the 25572 cone and 25520 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25572/25520.", "The pure-numeric inch family at 38.1 mm bore (82.931×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25572/25520 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 25572 and 25520; use undercut shoulders so the rings seat on the face, not on a radius.", "Replacing one half of an adjusted pair without resetting end play negates the 23.812 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ABMA makes the 38.1×82.931 mm envelope interchangeable, not the ratings: NTN prints 84.5/98 kN for this execution and another make of the same number can differ in roller complement.", "The 84.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25572/25520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25572/25520?", "a": "4T-25572/25520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 82.931 mm outside diameter and 23.812 mm assembled width T (3.265 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 84.5 kN, C0 98 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 646 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25572/25520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25572 cone or the 25520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 84.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25572/25520 and a metric ISO 355 tapered bearing?", "a": "4T-25572/25520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×82.931×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25572/25520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25572/25520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25572/25520 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25572/25520 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25572-25520", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.1×82.931×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25572-25520", "25572-25520", "4T-25572-25520", "25572-25520-NTN" ], "locale_variants": {} }, { "sku": "3875-3820", "brand": "NTN", "manufacturer_designation": "NTN 4T-3875/3820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 85.725, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 116, "static_load_kN": 132, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 861, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-3875/3820 at 38.1 mm bore (1.5 in), 85.725 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 4,500 r/min and an oil ceiling of 6,000 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 3875 sits in the pure-numeric inch family. Contact-angle geometry of the pure-numeric inch family gives 4T-3875/3820 its radial/axial load split — at 116/132 kN the static rating is about 1.14× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-3875/3820: press the 3820 cup square into the 85.725 mm seat first, then bring the 3875 cone (on its 38.1 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-3875/3820, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3875/3820.", "The pure-numeric inch family at 38.1 mm bore (85.725×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3875/3820 reference at purchase.", "An unloaded 4T-3875/3820 near 4,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "ABMA makes the 38.1×85.725 mm envelope interchangeable, not the ratings: NTN prints 116/132 kN for this execution and another make of the same number can differ in roller complement.", "Fit selection follows the rotating ring: a rotating cone on a 38.1 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 116/132 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3875/3820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3875/3820?", "a": "4T-3875/3820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 85.725 mm outside diameter and 30.162 mm assembled width T (3.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 116 kN, C0 132 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 861 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3875/3820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3875 cone or the 3820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 116/132 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3875/3820 and a metric ISO 355 tapered bearing?", "a": "4T-3875/3820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×85.725×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3875/3820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3875/3820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3875/3820 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3875/3820 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3875", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3875-3820", "3875-3820", "4T-3875-3820" ], "locale_variants": {} }, { "sku": "3580-3525", "brand": "NTN", "manufacturer_designation": "NTN 4T-3580/3525", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 87.312, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 104, "static_load_kN": 117, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5900, "weight_g": 881, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.5 in (38.1 mm) shaft position as 4T-3580/3525: cone 3580, cup 3525, profiled rollers and a pressed-steel cage, rated 104 kN basic dynamic and 117 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 3580 sits in the pure-numeric inch family. Contact-angle geometry of the pure-numeric inch family gives 4T-3580/3525 its radial/axial load split — at 104/117 kN the static rating is about 1.13× C, typical of inch tapered sets proportioned for combined duty. The printed 104/117 kN ratings belong to the assembled 3580+3525 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-3580/3525 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3580/3525.", "The pure-numeric inch family at 38.1 mm bore (87.312×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3580/3525 reference at purchase.", "Open 4T-3580/3525 sets have no seals: a hub or gearbox needs external sealing or the 4,400 r/min grease figure is meaningless once water reaches the cone rib.", "An unloaded 4T-3580/3525 near 4,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Fit selection follows the rotating ring: a rotating cone on a 38.1 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 104/117 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3580/3525; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3580/3525?", "a": "4T-3580/3525 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 87.312 mm outside diameter and 30.162 mm assembled width T (3.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 104 kN, C0 117 kN, grease limiting speed 4,400 r/min, oil speed 5,900 r/min, mass about 881 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3580/3525 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3580 cone or the 3525 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 104/117 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3580/3525 and a metric ISO 355 tapered bearing?", "a": "4T-3580/3525 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×87.312×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3580/3525 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3580/3525 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3580/3525 list two speeds, 4,400 and 5,900 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3580/3525 at 5,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3580", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3580-3525", "3580-3525", "4T-3580-3525" ], "locale_variants": {} }, { "sku": "418-414-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-418/414", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 88.5, "B_mm": 26.988, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 106, "static_load_kN": 107, "limiting_speed_rpm": 4600, "max_rpm": 4600, "speed_oil_rpm": 6100, "weight_g": 843, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-418/414 is the NTN 4T catalogue entry for a 38.1×88.5×26.988 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-418/414 are separately stocked parts: a worn 414 cup can be replaced against the existing 418 cone, provided the new cup carries the identical reference — pairing across references changes the 26.988 mm assembled width and the rating. The 25.2 mm radial section over the 38.1 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 106/107 kN ratings belong to the assembled 418+414 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 418 cone and 414 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-418/414.", "The pure-numeric inch family at 38.1 mm bore (88.5×26.988 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 418/414 reference at purchase.", "ABMA makes the 38.1×88.5 mm envelope interchangeable, not the ratings: NTN prints 106/107 kN for this execution and another make of the same number can differ in roller complement.", "Never drive the 88.5 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (26.988 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 106/107 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-418/414; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-418/414?", "a": "4T-418/414 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 88.5 mm outside diameter and 26.988 mm assembled width T (3.484 × 1.063 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 106 kN, C0 107 kN, grease limiting speed 4,600 r/min, oil speed 6,100 r/min, mass about 843 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-418/414 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 418 cone or the 414 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 106/107 kN ratings change with the cup." }, { "q": "What is the difference between 4T-418/414 and a metric ISO 355 tapered bearing?", "a": "4T-418/414 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×88.5×26.988 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-418/414 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 418/414 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-418/414 list two speeds, 4,600 and 6,100 r/min?", "a": "The lower figure, 4,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-418/414 at 6,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "418-414", "equiv_brand": "SKF", "level": "partial", "note": "Same 38.1×88.5×26.988 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-418-414", "418-414", "4T-418-414", "418-414-NTN" ], "locale_variants": {} }, { "sku": "44150-44348", "brand": "NTN", "manufacturer_designation": "NTN 4T-44150/44348", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 38.1, "D_mm": 88.5, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 78.5, "static_load_kN": 78, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 714, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-44150/44348 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 44150 and cup 44348 delivered as a matched, separable pair of 38.1 mm bore and 88.5 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 44150 identifies the cone of 38.1 mm (1.5 in) bore by catalogue lookup, and 44348 fixes the 88.5 mm OD. Contact-angle geometry of the pure-numeric inch family gives 4T-44150/44348 its radial/axial load split — at 78.5/78 kN the static rating is about 0.99× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 44348: within the pure-numeric inch family tables the 44150 cone is listed against several cup options, and it is the cup that fixes the 88.5 mm OD and the 25.4 mm assembled width — quote the full 44150/44348 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-44150/44348 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 38.1 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-44150/44348.", "The pure-numeric inch family at 38.1 mm bore (88.5×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 44150/44348 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 38.1 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Open 4T-44150/44348 sets have no seals: a hub or gearbox needs external sealing or the 4,000 r/min grease figure is meaningless once water reaches the cone rib.", "Shaft and housing fillets must clear the ring chamfers of 44150 and 44348; use undercut shoulders so the rings seat on the face, not on a radius.", "The 78.5/78 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-44150/44348; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-44150/44348?", "a": "4T-44150/44348 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 88.5 mm outside diameter and 25.4 mm assembled width T (3.484 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 78.5 kN, C0 78 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 714 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-44150/44348 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 44150 cone or the 44348 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 78.5/78 kN ratings change with the cup." }, { "q": "What is the difference between 4T-44150/44348 and a metric ISO 355 tapered bearing?", "a": "4T-44150/44348 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 38.1×88.5×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-44150/44348 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 44150/44348 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-44150/44348 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-44150/44348 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "44150", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-44150-44348", "44150-44348", "4T-44150-44348" ], "locale_variants": {} }, { "sku": "2789-2720", "brand": "NTN", "manufacturer_designation": "NTN 4T-2789/2720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 39.688, "D_mm": 76.2, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 81, "static_load_kN": 90.5, "limiting_speed_rpm": 5100, "max_rpm": 5100, "speed_oil_rpm": 6800, "weight_g": 475, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-2789/2720 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-2789/2720 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Catalogue mass of the 4T-2789/2720 cone-plus-cup set is 475 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-2789/2720: press the 2720 cup square into the 76.2 mm seat first, then bring the 2789 cone (on its 39.688 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Fillet radii must clear the chamfers of the 2789 cone and 2720 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 39.688 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2789/2720.", "The pure-numeric inch family at 39.688 mm bore (76.2×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2789/2720 reference at purchase.", "ABMA makes the 39.688×76.2 mm envelope interchangeable, not the ratings: NTN prints 81/90.5 kN for this execution and another make of the same number can differ in roller complement.", "Open 4T-2789/2720 sets have no seals: a hub or gearbox needs external sealing or the 5,100 r/min grease figure is meaningless once water reaches the cone rib.", "An unloaded 4T-2789/2720 near 5,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 81/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2789/2720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2789/2720?", "a": "4T-2789/2720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 39.688 mm bore (1.563 in), 76.2 mm outside diameter and 23.812 mm assembled width T (3 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 81 kN, C0 90.5 kN, grease limiting speed 5,100 r/min, oil speed 6,800 r/min, mass about 475 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2789/2720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2789 cone or the 2720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 81/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2789/2720 and a metric ISO 355 tapered bearing?", "a": "4T-2789/2720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 39.688×76.2×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2789/2720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2789/2720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2789/2720 list two speeds, 5,100 and 6,800 r/min?", "a": "The lower figure, 5,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2789/2720 at 6,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2789-2729", "equiv_brand": "SKF", "level": "partial", "note": "Same 39.688×76.2×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2789-2720", "2789-2720", "4T-2789-2720" ], "locale_variants": {} }, { "sku": "3382-3321", "brand": "NTN", "manufacturer_designation": "NTN 4T-3382/3321", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 39.688, "D_mm": 77.534, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 105, "static_load_kN": 112, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 669, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.563 in (39.688 mm) shaft position as 4T-3382/3321: cone 3382, cup 3321, profiled rollers and a pressed-steel cage, rated 105 kN basic dynamic and 112 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 3382 identifies the cone of 39.688 mm (1.563 in) bore by catalogue lookup, and 3321 fixes the 77.534 mm OD. Speed planning uses both catalogue columns: grease 4,800 r/min is the mechanical ceiling for 4T-3382/3321, oil 6,400 r/min with circulating oil — a 1,600 r/min margin at this size. The printed 105/112 kN ratings belong to the assembled 3382+3321 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-3382/3321 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 39.688 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3382/3321.", "The pure-numeric inch family at 39.688 mm bore (77.534×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3382/3321 reference at purchase.", "Grease packs must leave free volume inside the 29.37 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,400 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 39.688 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 3382/3321 pair at ordering: the 3382 cone also ships against sibling cups, and a cup from another reference changes the 29.37 mm assembled width and the rating.", "The 105/112 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3382/3321; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3382/3321?", "a": "4T-3382/3321 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 39.688 mm bore (1.563 in), 77.534 mm outside diameter and 29.37 mm assembled width T (3.053 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 105 kN, C0 112 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 669 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3382/3321 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3382 cone or the 3321 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 105/112 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3382/3321 and a metric ISO 355 tapered bearing?", "a": "4T-3382/3321 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 39.688×77.534×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3382/3321 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3382/3321 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3382/3321 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3382/3321 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3382-3339", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-3382 paired with a different cup (3339): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3382-3321", "3382-3321", "4T-3382-3321" ], "locale_variants": {} }, { "sku": "26880-26822", "brand": "NTN", "manufacturer_designation": "NTN 4T-26880/26822", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 39.688, "D_mm": 79.375, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 97.5, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 556, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-26880/26822 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 39.688×79.375×23.812 mm (assembled width T), for a shaft of about 39.688 mm (1.563 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 26880/26822 without it. Contact-angle geometry of the pure-numeric inch family gives 4T-26880/26822 its radial/axial load split — at 85/97.5 kN the static rating is about 1.15× C, typical of inch tapered sets proportioned for combined duty. The printed 85/97.5 kN ratings belong to the assembled 26880+26822 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-26880/26822 run near 4,800 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 39.688 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-26880/26822.", "The pure-numeric inch family at 39.688 mm bore (79.375×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 26880/26822 reference at purchase.", "Never drive the 79.375 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Quote the full 26880/26822 pair at ordering: the 26880 cone also ships against sibling cups, and a cup from another reference changes the 23.812 mm assembled width and the rating.", "ABMA makes the 39.688×79.375 mm envelope interchangeable, not the ratings: NTN prints 85/97.5 kN for this execution and another make of the same number can differ in roller complement.", "The 85/97.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-26880/26822; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-26880/26822?", "a": "4T-26880/26822 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 39.688 mm bore (1.563 in), 79.375 mm outside diameter and 23.812 mm assembled width T (3.125 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 97.5 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 556 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-26880/26822 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 26880 cone or the 26822 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/97.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-26880/26822 and a metric ISO 355 tapered bearing?", "a": "4T-26880/26822 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 39.688×79.375×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-26880/26822 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 26880/26822 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-26880/26822 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-26880/26822 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "26880", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-26880-26822", "26880-26822", "4T-26880-26822" ], "locale_variants": {} }, { "sku": "3382-3339", "brand": "NTN", "manufacturer_designation": "NTN 4T-3382/3339", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 39.688, "D_mm": 80.035, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 105, "static_load_kN": 112, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 666, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3382/3339 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 3382 identifies the cone of 39.688 mm (1.563 in) bore by catalogue lookup, and 3339 fixes the 80.035 mm OD. Grease relubrication at the 4,800 r/min limiting speed targets the cone-rib contact; sustaining 6,400 r/min needs an oil supply directed at the large roller ends. The printed 105/112 kN ratings belong to the assembled 3382+3339 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 39.688 mm cone with an induction heater (max 120 °C) and press the 80.035 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 39.688 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3382/3339.", "The pure-numeric inch family at 39.688 mm bore (80.035×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3382/3339 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 39.688 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Replacing one half of an adjusted pair without resetting end play negates the 29.37 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (29.37 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 105/112 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3382/3339; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3382/3339?", "a": "4T-3382/3339 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 39.688 mm bore (1.563 in), 80.035 mm outside diameter and 29.37 mm assembled width T (3.151 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 105 kN, C0 112 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 666 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3382/3339 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3382 cone or the 3339 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 105/112 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3382/3339 and a metric ISO 355 tapered bearing?", "a": "4T-3382/3339 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 39.688×80.035×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3382/3339 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3382/3339 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3382/3339 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3382/3339 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3382-3321", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-3382 paired with a different cup (3321): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3382-3339", "3382-3339", "4T-3382-3339" ], "locale_variants": {} }, { "sku": "3386-3320", "brand": "NTN", "manufacturer_designation": "NTN 4T-3386/3320", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 39.688, "D_mm": 80.167, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 105, "static_load_kN": 112, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 672, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3386/3320 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-3386/3320 are separately stocked parts: a worn 3320 cup can be replaced against the existing 3386 cone, provided the new cup carries the identical reference — pairing across references changes the 29.37 mm assembled width and the rating. Selection: C 105 kN against C0 112 kN gives a C0/C ratio of 1.07 for the 39.688 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-3386/3320: press the 3320 cup square into the 80.167 mm seat first, then bring the 3386 cone (on its 39.688 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 39.688 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 39.688 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3386/3320.", "The pure-numeric inch family at 39.688 mm bore (80.167×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3386/3320 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 3386 and 3320; use undercut shoulders so the rings seat on the face, not on a radius.", "Replacing one half of an adjusted pair without resetting end play negates the 29.37 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Grease packs must leave free volume inside the 29.37 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,400 r/min raises temperature and destroys the setting.", "The 105/112 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3386/3320; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3386/3320?", "a": "4T-3386/3320 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 39.688 mm bore (1.563 in), 80.167 mm outside diameter and 29.37 mm assembled width T (3.156 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 105 kN, C0 112 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 672 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3386/3320 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3386 cone or the 3320 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 105/112 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3386/3320 and a metric ISO 355 tapered bearing?", "a": "4T-3386/3320 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 39.688×80.167×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3386/3320 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3386/3320 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3386/3320 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3386/3320 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3386", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3386-3320", "3386-3320", "4T-3386-3320" ], "locale_variants": {} }, { "sku": "44158-44348", "brand": "NTN", "manufacturer_designation": "NTN 4T-44158/44348", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 39.688, "D_mm": 88.5, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 78.5, "static_load_kN": 78, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 691, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-44158/44348 is the NTN 4T catalogue entry for a 39.688×88.5×25.4 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Reading the designation: 4T-44158/44348 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Catalogue mass of the 4T-44158/44348 cone-plus-cup set is 691 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 44348: within the pure-numeric inch family tables the 44158 cone is listed against several cup options, and it is the cup that fixes the 88.5 mm OD and the 25.4 mm assembled width — quote the full 44158/44348 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 39.688 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 39.688 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-44158/44348.", "The pure-numeric inch family at 39.688 mm bore (88.5×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 44158/44348 reference at purchase.", "Open 4T-44158/44348 sets have no seals: a hub or gearbox needs external sealing or the 4,000 r/min grease figure is meaningless once water reaches the cone rib.", "Never drive the 88.5 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "An unloaded 4T-44158/44348 near 4,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 78.5/78 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-44158/44348; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-44158/44348?", "a": "4T-44158/44348 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 39.688 mm bore (1.563 in), 88.5 mm outside diameter and 25.4 mm assembled width T (3.484 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 78.5 kN, C0 78 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 691 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-44158/44348 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 44158 cone or the 44348 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 78.5/78 kN ratings change with the cup." }, { "q": "What is the difference between 4T-44158/44348 and a metric ISO 355 tapered bearing?", "a": "4T-44158/44348 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 39.688×88.5×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-44158/44348 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 44158/44348 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-44158/44348 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-44158/44348 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "44158", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-44158-44348", "44158-44348", "4T-44158-44348" ], "locale_variants": {} }, { "sku": "28158-28300", "brand": "NTN", "manufacturer_designation": "NTN 4T-28158/28300", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 76.2, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 61.5, "static_load_kN": 63, "limiting_speed_rpm": 5000, "max_rpm": 5000, "speed_oil_rpm": 6700, "weight_g": 387, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.575 in (40 mm) shaft position as 4T-28158/28300: cone 28158, cup 28300, profiled rollers and a pressed-steel cage, rated 61.5 kN basic dynamic and 63 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 28158 sits in the pure-numeric inch family. Catalogue mass of the 4T-28158/28300 cone-plus-cup set is 387 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-28158/28300: press the 28300 cup square into the 76.2 mm seat first, then bring the 28158 cone (on its 40 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-28158/28300 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 40 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-28158/28300.", "The pure-numeric inch family at 40 mm bore (76.2×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28158/28300 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 40 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 40 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 20.638 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,700 r/min raises temperature and destroys the setting.", "The 61.5/63 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28158/28300; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28158/28300?", "a": "4T-28158/28300 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 40 mm bore (1.575 in), 76.2 mm outside diameter and 20.638 mm assembled width T (3 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 61.5 kN, C0 63 kN, grease limiting speed 5,000 r/min, oil speed 6,700 r/min, mass about 387 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28158/28300 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28158 cone or the 28300 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 61.5/63 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28158/28300 and a metric ISO 355 tapered bearing?", "a": "4T-28158/28300 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 40×76.2×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28158/28300 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28158/28300 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28158/28300 list two speeds, 5,000 and 6,700 r/min?", "a": "The lower figure, 5,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28158/28300 at 6,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28158", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28158-28300", "28158-28300", "4T-28158-28300" ], "locale_variants": {} }, { "sku": "344-332-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-344/332", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 75.5, "static_load_kN": 75, "limiting_speed_rpm": 4700, "max_rpm": 4700, "speed_oil_rpm": 6300, "weight_g": 479, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-344/332 is the NTN 4T catalogue entry for a 40×80×21 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 344 sits in the pure-numeric inch family. Selection: C 75.5 kN against C0 75 kN gives a C0/C ratio of 0.99 for the 40 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 332: within the pure-numeric inch family tables the 344 cone is listed against several cup options, and it is the cup that fixes the 80 mm OD and the 21 mm assembled width — quote the full 344/332 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-344/332, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 40 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-344/332.", "The pure-numeric inch family at 40 mm bore (80×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 344/332 reference at purchase.", "Do not confuse T (21 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Inch and metric bores collide on paper — 40 mm is 1.575 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Shaft and housing fillets must clear the ring chamfers of 344 and 332; use undercut shoulders so the rings seat on the face, not on a radius.", "The 75.5/75 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-344/332; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-344/332?", "a": "4T-344/332 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 40 mm bore (1.575 in), 80 mm outside diameter and 21 mm assembled width T (3.15 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 75.5 kN, C0 75 kN, grease limiting speed 4,700 r/min, oil speed 6,300 r/min, mass about 479 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-344/332 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 344 cone or the 332 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 75.5/75 kN ratings change with the cup." }, { "q": "What is the difference between 4T-344/332 and a metric ISO 355 tapered bearing?", "a": "4T-344/332 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 40×80×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-344/332 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 344/332 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-344/332 list two speeds, 4,700 and 6,300 r/min?", "a": "The lower figure, 4,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-344/332 at 6,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "344-332", "equiv_brand": "SKF", "level": "partial", "note": "Same 40×80×21 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "344-332AA", "equiv_brand": "SKF", "level": "partial", "note": "Same 40×80×21 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-344-332", "344-332", "4T-344-332", "344-332-NTN" ], "locale_variants": {} }, { "sku": "350A-354A", "brand": "NTN", "manufacturer_designation": "NTN 4T-350A/354A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 85, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 77.5, "static_load_kN": 79.5, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5800, "weight_g": 566, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-350A/354A belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 350A/354A without it. Grease relubrication at the 4,400 r/min limiting speed targets the cone-rib contact; sustaining 5,800 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-350A/354A: press the 354A cup square into the 85 mm seat first, then bring the 350A cone (on its 40 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-350A/354A pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 40 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-350A/354A.", "The pure-numeric inch family at 40 mm bore (85×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 350A/354A reference at purchase.", "Grease packs must leave free volume inside the 20.638 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,800 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of 350A and 354A; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 20.638 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,800 r/min raises temperature and destroys the setting.", "The 77.5/79.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-350A/354A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-350A/354A?", "a": "4T-350A/354A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 40 mm bore (1.575 in), 85 mm outside diameter and 20.638 mm assembled width T (3.346 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 79.5 kN, grease limiting speed 4,400 r/min, oil speed 5,800 r/min, mass about 566 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-350A/354A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 350A cone or the 354A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 77.5/79.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-350A/354A and a metric ISO 355 tapered bearing?", "a": "4T-350A/354A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 40×85×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-350A/354A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 350A/354A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-350A/354A list two speeds, 4,400 and 5,800 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-350A/354A at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "350A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "350a-354a", "4t-350a-354a", "350A-354A", "4T-350A-354A" ], "locale_variants": {} }, { "sku": "420-414", "brand": "NTN", "manufacturer_designation": "NTN 4T-420/414", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 88.5, "B_mm": 26.988, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 106, "static_load_kN": 107, "limiting_speed_rpm": 4600, "max_rpm": 4600, "speed_oil_rpm": 6100, "weight_g": 817, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 40 mm carrying combined radial and thrust load, NTN lists 4T-420/414, a single-row 4T tapered roller set of 106 kN C and 107 kN C0 inside the 88.5 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 420/414 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 26.988 mm T of each 4T-420/414 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-420/414: press the 414 cup square into the 88.5 mm seat first, then bring the 420 cone (on its 40 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Fillet radii must clear the chamfers of the 420 cone and 414 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 40 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-420/414.", "The pure-numeric inch family at 40 mm bore (88.5×26.988 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 420/414 reference at purchase.", "ABMA makes the 40×88.5 mm envelope interchangeable, not the ratings: NTN prints 106/107 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 420/414 pair at ordering: the 420 cone also ships against sibling cups, and a cup from another reference changes the 26.988 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of 420 and 414; use undercut shoulders so the rings seat on the face, not on a radius.", "The 106/107 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-420/414; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-420/414?", "a": "4T-420/414 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 40 mm bore (1.575 in), 88.5 mm outside diameter and 26.988 mm assembled width T (3.484 × 1.063 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 106 kN, C0 107 kN, grease limiting speed 4,600 r/min, oil speed 6,100 r/min, mass about 817 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-420/414 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 420 cone or the 414 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 106/107 kN ratings change with the cup." }, { "q": "What is the difference between 4T-420/414 and a metric ISO 355 tapered bearing?", "a": "4T-420/414 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 40×88.5×26.988 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-420/414 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 420/414 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-420/414 list two speeds, 4,600 and 6,100 r/min?", "a": "The lower figure, 4,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-420/414 at 6,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "420", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-420-414", "420-414", "4T-420-414" ], "locale_variants": {} }, { "sku": "543-532X", "brand": "NTN", "manufacturer_designation": "NTN 4T-543/532X", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 107.95, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 157, "static_load_kN": 177, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 1770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-543/532X is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 40×107.95×36.512 mm (assembled width T), for a shaft of about 40 mm (1.575 in). Reading the designation: 4T-543/532X follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 34.0 mm radial section over the 40 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 157/177 kN ratings belong to the assembled 543+532X pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-543/532X run near 3,600 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 40 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-543/532X.", "The pure-numeric inch family at 40 mm bore (107.95×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 543/532X reference at purchase.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 36.512 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 40 mm is 1.575 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 157/177 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-543/532X; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-543/532X?", "a": "4T-543/532X is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 40 mm bore (1.575 in), 107.95 mm outside diameter and 36.512 mm assembled width T (4.25 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 157 kN, C0 177 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1770 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-543/532X interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 543 cone or the 532X cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 157/177 kN ratings change with the cup." }, { "q": "What is the difference between 4T-543/532X and a metric ISO 355 tapered bearing?", "a": "4T-543/532X follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 40×107.95×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-543/532X mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 543/532X references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-543/532X list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-543/532X at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "543", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-543-532x", "543-532x", "543-532X", "4T-543-532X" ], "locale_variants": {} }, { "sku": "HM801349-HM801310", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM801349/HM801310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 40.483, "D_mm": 82.55, "B_mm": 29.37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 96.5, "static_load_kN": 117, "limiting_speed_rpm": 4700, "max_rpm": 4700, "speed_oil_rpm": 6200, "weight_g": 734, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-HM801349/HM801310 at 40.483 mm bore (1.594 in), 82.55 mm cup OD and 29.37 mm assembled T, with a grease limiting speed of 4,700 r/min and an oil ceiling of 6,200 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote HM801349/HM801310 without it. Grease relubrication at the 4,700 r/min limiting speed targets the cone-rib contact; sustaining 6,200 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-HM801349/HM801310: press the HM801310 cup square into the 82.55 mm seat first, then bring the HM801349 cone (on its 40.483 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-HM801349/HM801310 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 40.483 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM801349/HM801310.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 40.483 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "ABMA makes the 40.483×82.55 mm envelope interchangeable, not the ratings: NTN prints 96.5/117 kN for this execution and another make of the same number can differ in roller complement.", "Fit selection follows the rotating ring: a rotating cone on a 40.483 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (29.37 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 96.5/117 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM801349/HM801310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM801349/HM801310?", "a": "4T-HM801349/HM801310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 40.483 mm bore (1.594 in), 82.55 mm outside diameter and 29.37 mm assembled width T (3.25 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 96.5 kN, C0 117 kN, grease limiting speed 4,700 r/min, oil speed 6,200 r/min, mass about 734 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM801349/HM801310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM801349 cone or the HM801310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 96.5/117 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM801349/HM801310 and a metric ISO 355 tapered bearing?", "a": "4T-HM801349/HM801310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 40.483×82.55×29.37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM801349/HM801310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM801349/HM801310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM801349/HM801310 list two speeds, 4,700 and 6,200 r/min?", "a": "The lower figure, 4,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM801349/HM801310 at 6,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM801349", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm801349-hm801310", "hm801349-hm801310", "HM801349-HM801310", "4T-HM801349-HM801310" ], "locale_variants": {} }, { "sku": "LM300849-LM300811", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM300849/LM300811", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 40.988, "D_mm": 67.975, "B_mm": 17.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 51, "static_load_kN": 62.5, "limiting_speed_rpm": 5300, "max_rpm": 5300, "speed_oil_rpm": 7000, "weight_g": 232, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-LM300849/LM300811 denotes the light-medium LM family of NTN inch tapered roller bearings — cone LM300849 and cup LM300811 delivered as a matched, separable pair of 40.988 mm bore and 67.975 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote LM300849/LM300811 without it. The 13.5 mm radial section over the 40.988 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for LM300811: within the light-medium LM family tables the LM300849 cone is listed against several cup options, and it is the cup that fixes the 67.975 mm OD and the 17.5 mm assembled width — quote the full LM300849/LM300811 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 40.988 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 40.988 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM300849/LM300811.", "The light-medium LM family at 40.988 mm bore (67.975×17.5 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM300849/LM300811 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of LM300849 and LM300811; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-LM300849/LM300811 near 5,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Quote the full LM300849/LM300811 pair at ordering: the LM300849 cone also ships against sibling cups, and a cup from another reference changes the 17.5 mm assembled width and the rating.", "The 51/62.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM300849/LM300811; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM300849/LM300811?", "a": "4T-LM300849/LM300811 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 40.988 mm bore (1.614 in), 67.975 mm outside diameter and 17.5 mm assembled width T (2.676 × 0.689 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 51 kN, C0 62.5 kN, grease limiting speed 5,300 r/min, oil speed 7,000 r/min, mass about 232 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM300849/LM300811 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM300849 cone or the LM300811 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 51/62.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM300849/LM300811 and a metric ISO 355 tapered bearing?", "a": "4T-LM300849/LM300811 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 40.988×67.975×17.5 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM300849/LM300811 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM300849/LM300811 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM300849/LM300811 list two speeds, 5,300 and 7,000 r/min?", "a": "The lower figure, 5,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM300849/LM300811 at 7,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM300849-811", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm300849-lm300811", "lm300849-lm300811", "LM300849-LM300811", "4T-LM300849-LM300811" ], "locale_variants": {} }, { "sku": "18590-18520-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-18590/18520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 73.025, "B_mm": 16.667, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 51, "static_load_kN": 55.5, "limiting_speed_rpm": 5000, "max_rpm": 5000, "speed_oil_rpm": 6600, "weight_g": 283, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-18590/18520 is the NTN 4T catalogue entry for a 41.275×73.025×16.667 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 18590 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 5,000 r/min is the mechanical ceiling for 4T-18590/18520, oil 6,600 r/min with circulating oil — a 1,600 r/min margin at this size. Housing fitment sequence for 4T-18590/18520: press the 18520 cup square into the 73.025 mm seat first, then bring the 18590 cone (on its 41.275 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Fillet radii must clear the chamfers of the 18590 cone and 18520 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-18590/18520.", "The pure-numeric inch family at 41.275 mm bore (73.025×16.667 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 18590/18520 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 16.667 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (16.667 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 41.275 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 51/55.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-18590/18520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-18590/18520?", "a": "4T-18590/18520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 73.025 mm outside diameter and 16.667 mm assembled width T (2.875 × 0.656 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 51 kN, C0 55.5 kN, grease limiting speed 5,000 r/min, oil speed 6,600 r/min, mass about 283 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-18590/18520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 18590 cone or the 18520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 51/55.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-18590/18520 and a metric ISO 355 tapered bearing?", "a": "4T-18590/18520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×73.025×16.667 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-18590/18520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 18590/18520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-18590/18520 list two speeds, 5,000 and 6,600 r/min?", "a": "The lower figure, 5,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-18590/18520 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "18590-18520", "equiv_brand": "SKF", "level": "partial", "note": "Same 41.275×73.025×16.667 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-18590-18520", "18590-18520", "4T-18590-18520", "18590-18520-NTN" ], "locale_variants": {} }, { "sku": "LM501349-LM501310", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM501349/LM501310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 73.431, "B_mm": 19.558, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 62, "static_load_kN": 69.5, "limiting_speed_rpm": 5000, "max_rpm": 5000, "speed_oil_rpm": 6600, "weight_g": 334, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-LM501349/LM501310 denotes the light-medium LM family of NTN inch tapered roller bearings — cone LM501349 and cup LM501310 delivered as a matched, separable pair of 41.275 mm bore and 73.431 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote LM501349/LM501310 without it. Imperial cross-check for the drawing: 41.275×73.431×19.558 mm converts to 1.625 × 2.891 × 0.77 in; the ABMA envelope swaps with like-numbered inch parts but the 62/69.5 kN ratings are NTN-specific. The printed 62/69.5 kN ratings belong to the assembled LM501349+LM501310 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-LM501349/LM501310; reverse the fit logic when the cup rotates.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM501349/LM501310.", "The light-medium LM family at 41.275 mm bore (73.431×19.558 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM501349/LM501310 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 19.558 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Quote the full LM501349/LM501310 pair at ordering: the LM501349 cone also ships against sibling cups, and a cup from another reference changes the 19.558 mm assembled width and the rating.", "Never drive the 73.431 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 62/69.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM501349/LM501310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM501349/LM501310?", "a": "4T-LM501349/LM501310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 73.431 mm outside diameter and 19.558 mm assembled width T (2.891 × 0.77 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 62 kN, C0 69.5 kN, grease limiting speed 5,000 r/min, oil speed 6,600 r/min, mass about 334 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM501349/LM501310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM501349 cone or the LM501310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 62/69.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM501349/LM501310 and a metric ISO 355 tapered bearing?", "a": "4T-LM501349/LM501310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×73.431×19.558 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM501349/LM501310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM501349/LM501310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM501349/LM501310 list two speeds, 5,000 and 6,600 r/min?", "a": "The lower figure, 5,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM501349/LM501310 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM501349-310", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM501349-314", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "LM501349-LM501314", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-LM501349 paired with a different cup (LM501314): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm501349-lm501310", "lm501349-lm501310", "LM501349-LM501310", "4T-LM501349-LM501310" ], "locale_variants": {} }, { "sku": "LM501349-LM501314", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM501349/LM501314", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 73.431, "B_mm": 21.43, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 62, "static_load_kN": 69.5, "limiting_speed_rpm": 5000, "max_rpm": 5000, "speed_oil_rpm": 6600, "weight_g": 354, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 41.275 mm carrying combined radial and thrust load, NTN lists 4T-LM501349/LM501314, a single-row 4T tapered roller set of 62 kN C and 69.5 kN C0 inside the 73.431 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: LM501349 identifies the cone of 41.275 mm (1.625 in) bore by catalogue lookup, and LM501314 fixes the 73.431 mm OD. Contact-angle geometry of the light-medium LM family gives 4T-LM501349/LM501314 its radial/axial load split — at 62/69.5 kN the static rating is about 1.12× C, typical of inch tapered sets proportioned for combined duty. The printed 62/69.5 kN ratings belong to the assembled LM501349+LM501314 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-LM501349/LM501314 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM501349/LM501314.", "The light-medium LM family at 41.275 mm bore (73.431×21.43 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM501349/LM501314 reference at purchase.", "Open 4T-LM501349/LM501314 sets have no seals: a hub or gearbox needs external sealing or the 5,000 r/min grease figure is meaningless once water reaches the cone rib.", "Do not confuse T (21.43 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Grease packs must leave free volume inside the 21.43 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,600 r/min raises temperature and destroys the setting.", "The 62/69.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM501349/LM501314; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM501349/LM501314?", "a": "4T-LM501349/LM501314 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 73.431 mm outside diameter and 21.43 mm assembled width T (2.891 × 0.844 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 62 kN, C0 69.5 kN, grease limiting speed 5,000 r/min, oil speed 6,600 r/min, mass about 354 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM501349/LM501314 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM501349 cone or the LM501314 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 62/69.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM501349/LM501314 and a metric ISO 355 tapered bearing?", "a": "4T-LM501349/LM501314 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×73.431×21.43 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM501349/LM501314 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM501349/LM501314 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM501349/LM501314 list two speeds, 5,000 and 6,600 r/min?", "a": "The lower figure, 5,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM501349/LM501314 at 6,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM501349-310", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "LM501349-314", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM501349-LM501310", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-LM501349 paired with a different cup (LM501310): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm501349-lm501314", "lm501349-lm501314", "LM501349-LM501314", "4T-LM501349-LM501314" ], "locale_variants": {} }, { "sku": "11162-11300-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-11162/11300", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 76.2, "B_mm": 18.009, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 47, "static_load_kN": 51.5, "limiting_speed_rpm": 4900, "max_rpm": 4900, "speed_oil_rpm": 6500, "weight_g": 337, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-11162/11300 is the NTN 4T catalogue entry for a 41.275×76.2×18.009 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Reading the designation: 4T-11162/11300 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Selection: C 47 kN against C0 51.5 kN gives a C0/C ratio of 1.10 for the 41.275 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-11162/11300: press the 11300 cup square into the 76.2 mm seat first, then bring the 11162 cone (on its 41.275 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 41.275 mm cone with an induction heater (max 120 °C) and press the 76.2 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-11162/11300.", "The pure-numeric inch family at 41.275 mm bore (76.2×18.009 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 11162/11300 reference at purchase.", "Open 4T-11162/11300 sets have no seals: a hub or gearbox needs external sealing or the 4,900 r/min grease figure is meaningless once water reaches the cone rib.", "Do not confuse T (18.009 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Shaft and housing fillets must clear the ring chamfers of 11162 and 11300; use undercut shoulders so the rings seat on the face, not on a radius.", "The 47/51.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-11162/11300; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-11162/11300?", "a": "4T-11162/11300 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 76.2 mm outside diameter and 18.009 mm assembled width T (3 × 0.709 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 47 kN, C0 51.5 kN, grease limiting speed 4,900 r/min, oil speed 6,500 r/min, mass about 337 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-11162/11300 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 11162 cone or the 11300 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 47/51.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-11162/11300 and a metric ISO 355 tapered bearing?", "a": "4T-11162/11300 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×76.2×18.009 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-11162/11300 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 11162/11300 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-11162/11300 list two speeds, 4,900 and 6,500 r/min?", "a": "The lower figure, 4,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-11162/11300 at 6,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "11162-11300", "equiv_brand": "SKF", "level": "partial", "note": "Same 41.275×76.2×18.009 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "11162-11315", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-11162 paired with a different cup (11315): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-11162-11300", "11162-11300", "4T-11162-11300", "11162-11300-NTN" ], "locale_variants": {} }, { "sku": "24780-24720-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-24780/24720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 76.2, "B_mm": 22.225, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 72, "static_load_kN": 80.5, "limiting_speed_rpm": 4900, "max_rpm": 4900, "speed_oil_rpm": 6500, "weight_g": 435, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-24780/24720 at 41.275 mm bore (1.625 in), 76.2 mm cup OD and 22.225 mm assembled T, with a grease limiting speed of 4,900 r/min and an oil ceiling of 6,500 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 24780 identifies the cone of 41.275 mm (1.625 in) bore by catalogue lookup, and 24720 fixes the 76.2 mm OD. The 1.7 kN of dynamic capacity per millimetre of bore summarises the 72 kN rating over the 41.275 mm bore — sanity-check any interchange candidate against this ratio and the 22.225 mm T. Housing fitment sequence for 4T-24780/24720: press the 24720 cup square into the 76.2 mm seat first, then bring the 24780 cone (on its 41.275 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Contact-pattern check with marking blue: a pattern biased to one roller end means the 41.275 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-24780/24720.", "The pure-numeric inch family at 41.275 mm bore (76.2×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 24780/24720 reference at purchase.", "Open 4T-24780/24720 sets have no seals: a hub or gearbox needs external sealing or the 4,900 r/min grease figure is meaningless once water reaches the cone rib.", "Shaft and housing fillets must clear the ring chamfers of 24780 and 24720; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of 24780 and 24720; use undercut shoulders so the rings seat on the face, not on a radius.", "The 72/80.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-24780/24720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-24780/24720?", "a": "4T-24780/24720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 76.2 mm outside diameter and 22.225 mm assembled width T (3 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 72 kN, C0 80.5 kN, grease limiting speed 4,900 r/min, oil speed 6,500 r/min, mass about 435 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-24780/24720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 24780 cone or the 24720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 72/80.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-24780/24720 and a metric ISO 355 tapered bearing?", "a": "4T-24780/24720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×76.2×22.225 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-24780/24720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 24780/24720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-24780/24720 list two speeds, 4,900 and 6,500 r/min?", "a": "The lower figure, 4,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-24780/24720 at 6,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "24780-24720", "equiv_brand": "SKF", "level": "partial", "note": "Same 41.275×76.2×22.225 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-24780-24720", "24780-24720", "4T-24780-24720", "24780-24720-NTN" ], "locale_variants": {} }, { "sku": "26882-26823", "brand": "NTN", "manufacturer_designation": "NTN 4T-26882/26823", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 76.2, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 97.5, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 490, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-26882/26823 is the NTN 4T catalogue entry for a 41.275×76.2×25.4 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 26882 identifies the cone of 41.275 mm (1.625 in) bore by catalogue lookup, and 26823 fixes the 76.2 mm OD. Selection: C 85 kN against C0 97.5 kN gives a C0/C ratio of 1.15 for the 41.275 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 26823: within the pure-numeric inch family tables the 26882 cone is listed against several cup options, and it is the cup that fixes the 76.2 mm OD and the 25.4 mm assembled width — quote the full 26882/26823 pair, never the cone alone. Mount the 41.275 mm cone with an induction heater (max 120 °C) and press the 76.2 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-26882/26823.", "The pure-numeric inch family at 41.275 mm bore (76.2×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 26882/26823 reference at purchase.", "ABMA makes the 41.275×76.2 mm envelope interchangeable, not the ratings: NTN prints 85/97.5 kN for this execution and another make of the same number can differ in roller complement.", "Open 4T-26882/26823 sets have no seals: a hub or gearbox needs external sealing or the 4,800 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 25.4 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 85/97.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-26882/26823; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-26882/26823?", "a": "4T-26882/26823 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 76.2 mm outside diameter and 25.4 mm assembled width T (3 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 97.5 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 490 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-26882/26823 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 26882 cone or the 26823 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/97.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-26882/26823 and a metric ISO 355 tapered bearing?", "a": "4T-26882/26823 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×76.2×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-26882/26823 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 26882/26823 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-26882/26823 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-26882/26823 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "26882-26824", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-26882 paired with a different cup (26824): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-26882-26823", "26882-26823", "4T-26882-26823" ], "locale_variants": {} }, { "sku": "26882-26824", "brand": "NTN", "manufacturer_designation": "NTN 4T-26882/26824", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 79.378, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 97.5, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 532, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-26882/26824 at 41.275 mm bore (1.625 in), 79.378 mm cup OD and 23.812 mm assembled T, with a grease limiting speed of 4,800 r/min and an oil ceiling of 6,400 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 26882/26824 without it. Contact-angle geometry of the pure-numeric inch family gives 4T-26882/26824 its radial/axial load split — at 85/97.5 kN the static rating is about 1.15× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 26824: within the pure-numeric inch family tables the 26882 cone is listed against several cup options, and it is the cup that fixes the 79.378 mm OD and the 23.812 mm assembled width — quote the full 26882/26824 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 41.275 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-26882/26824.", "The pure-numeric inch family at 41.275 mm bore (79.378×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 26882/26824 reference at purchase.", "An unloaded 4T-26882/26824 near 4,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Never drive the 79.378 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 85/97.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-26882/26824; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-26882/26824?", "a": "4T-26882/26824 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 79.378 mm outside diameter and 23.812 mm assembled width T (3.125 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 97.5 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 532 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-26882/26824 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 26882 cone or the 26824 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/97.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-26882/26824 and a metric ISO 355 tapered bearing?", "a": "4T-26882/26824 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×79.378×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-26882/26824 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 26882/26824 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-26882/26824 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-26882/26824 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "26882-26823", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-26882 paired with a different cup (26823): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-26882-26824", "26882-26824", "4T-26882-26824" ], "locale_variants": {} }, { "sku": "26885-26822", "brand": "NTN", "manufacturer_designation": "NTN 4T-26885/26822", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 79.378, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 97.5, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 535, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-26885/26822 is the NTN 4T catalogue entry for a 41.275×79.378×23.812 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 26885/26822 without it. Contact-angle geometry of the pure-numeric inch family gives 4T-26885/26822 its radial/axial load split — at 85/97.5 kN the static rating is about 1.15× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 26822: within the pure-numeric inch family tables the 26885 cone is listed against several cup options, and it is the cup that fixes the 79.378 mm OD and the 23.812 mm assembled width — quote the full 26885/26822 pair, never the cone alone. Running clearance of 4T-26885/26822 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-26885/26822.", "The pure-numeric inch family at 41.275 mm bore (79.378×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 26885/26822 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 41.275 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Replacing one half of an adjusted pair without resetting end play negates the 23.812 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-26885/26822 sets have no seals: a hub or gearbox needs external sealing or the 4,800 r/min grease figure is meaningless once water reaches the cone rib.", "The 85/97.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-26885/26822; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-26885/26822?", "a": "4T-26885/26822 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 79.378 mm outside diameter and 23.812 mm assembled width T (3.125 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 97.5 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 535 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-26885/26822 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 26885 cone or the 26822 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/97.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-26885/26822 and a metric ISO 355 tapered bearing?", "a": "4T-26885/26822 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×79.378×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-26885/26822 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 26885/26822 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-26885/26822 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-26885/26822 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "26885", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-26885-26822", "26885-26822", "4T-26885-26822" ], "locale_variants": {} }, { "sku": "11162-11315", "brand": "NTN", "manufacturer_designation": "NTN 4T-11162/11315", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 80, "B_mm": 18.009, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 47, "static_load_kN": 51.5, "limiting_speed_rpm": 4900, "max_rpm": 4900, "speed_oil_rpm": 6500, "weight_g": 389, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-11162/11315 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 11162 and cup 11315 delivered as a matched, separable pair of 41.275 mm bore and 80 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 11162/11315 without it. Catalogue mass of the 4T-11162/11315 cone-plus-cup set is 389 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-11162/11315: press the 11315 cup square into the 80 mm seat first, then bring the 11162 cone (on its 41.275 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-11162/11315 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-11162/11315.", "The pure-numeric inch family at 41.275 mm bore (80×18.009 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 11162/11315 reference at purchase.", "Grease packs must leave free volume inside the 18.009 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,500 r/min raises temperature and destroys the setting.", "Never drive the 80 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never drive the 80 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 47/51.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-11162/11315; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-11162/11315?", "a": "4T-11162/11315 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 80 mm outside diameter and 18.009 mm assembled width T (3.15 × 0.709 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 47 kN, C0 51.5 kN, grease limiting speed 4,900 r/min, oil speed 6,500 r/min, mass about 389 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-11162/11315 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 11162 cone or the 11315 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 47/51.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-11162/11315 and a metric ISO 355 tapered bearing?", "a": "4T-11162/11315 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×80×18.009 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-11162/11315 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 11162/11315 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-11162/11315 list two speeds, 4,900 and 6,500 r/min?", "a": "The lower figure, 4,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-11162/11315 at 6,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "11162-11300", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "11162-11300-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-11162 paired with a different cup (11300): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=180", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-11162-11315", "11162-11315", "4T-11162-11315" ], "locale_variants": {} }, { "sku": "336-332", "brand": "NTN", "manufacturer_designation": "NTN 4T-336/332", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 80, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 75.5, "static_load_kN": 75, "limiting_speed_rpm": 4700, "max_rpm": 4700, "speed_oil_rpm": 6300, "weight_g": 468, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-336/332 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 336 and cup 332 delivered as a matched, separable pair of 41.275 mm bore and 80 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 336 identifies the cone of 41.275 mm (1.625 in) bore by catalogue lookup, and 332 fixes the 80 mm OD. Grease relubrication at the 4,700 r/min limiting speed targets the cone-rib contact; sustaining 6,300 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-336/332: press the 332 cup square into the 80 mm seat first, then bring the 336 cone (on its 41.275 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-336/332, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-336/332.", "The pure-numeric inch family at 41.275 mm bore (80×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 336/332 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 336 and 332; use undercut shoulders so the rings seat on the face, not on a radius.", "Open 4T-336/332 sets have no seals: a hub or gearbox needs external sealing or the 4,700 r/min grease figure is meaningless once water reaches the cone rib.", "Do not confuse T (21 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 75.5/75 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-336/332; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-336/332?", "a": "4T-336/332 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 80 mm outside diameter and 21 mm assembled width T (3.15 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 75.5 kN, C0 75 kN, grease limiting speed 4,700 r/min, oil speed 6,300 r/min, mass about 468 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-336/332 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 336 cone or the 332 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 75.5/75 kN ratings change with the cup." }, { "q": "What is the difference between 4T-336/332 and a metric ISO 355 tapered bearing?", "a": "4T-336/332 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×80×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-336/332 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 336/332 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-336/332 list two speeds, 4,700 and 6,300 r/min?", "a": "The lower figure, 4,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-336/332 at 6,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "336", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-336-332", "336-332", "4T-336-332" ], "locale_variants": {} }, { "sku": "M802048-M802011", "brand": "NTN", "manufacturer_designation": "NTN 4T-M802048/M802011", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 82.55, "B_mm": 26.543, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 89, "static_load_kN": 104, "limiting_speed_rpm": 4600, "max_rpm": 4600, "speed_oil_rpm": 6100, "weight_g": 641, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-M802048/M802011 denotes the medium M family of NTN inch tapered roller bearings — cone M802048 and cup M802011 delivered as a matched, separable pair of 41.275 mm bore and 82.55 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — M802048 sits in the medium M family. Selection: C 89 kN against C0 104 kN gives a C0/C ratio of 1.17 for the 41.275 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-M802048/M802011: press the M802011 cup square into the 82.55 mm seat first, then bring the M802048 cone (on its 41.275 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-M802048/M802011 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-M802048/M802011.", "The medium M family at 41.275 mm bore (82.55×26.543 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full M802048/M802011 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of M802048 and M802011; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 41.275 mm is 1.625 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 41.275 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 89/104 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-M802048/M802011; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-M802048/M802011?", "a": "4T-M802048/M802011 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 82.55 mm outside diameter and 26.543 mm assembled width T (3.25 × 1.045 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 89 kN, C0 104 kN, grease limiting speed 4,600 r/min, oil speed 6,100 r/min, mass about 641 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-M802048/M802011 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the M802048 cone or the M802011 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 89/104 kN ratings change with the cup." }, { "q": "What is the difference between 4T-M802048/M802011 and a metric ISO 355 tapered bearing?", "a": "4T-M802048/M802011 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×82.55×26.543 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-M802048/M802011 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare M802048/M802011 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-M802048/M802011 list two speeds, 4,600 and 6,100 r/min?", "a": "The lower figure, 4,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-M802048/M802011 at 6,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "M802048-011", "equiv_brand": "SKF", "level": "partial", "note": "Same 41.275×82.55×26.543 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-m802048-m802011", "m802048-m802011", "M802048-M802011", "4T-M802048-M802011" ], "locale_variants": {} }, { "sku": "3880-3820", "brand": "NTN", "manufacturer_designation": "NTN 4T-3880/3820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 85.725, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 116, "static_load_kN": 132, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 814, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.625 in (41.275 mm) shaft position as 4T-3880/3820: cone 3880, cup 3820, profiled rollers and a pressed-steel cage, rated 116 kN basic dynamic and 132 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 3880 sits in the pure-numeric inch family. Grease relubrication at the 4,500 r/min limiting speed targets the cone-rib contact; sustaining 6,000 r/min needs an oil supply directed at the large roller ends. The printed 116/132 kN ratings belong to the assembled 3880+3820 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-3880/3820 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3880/3820.", "The pure-numeric inch family at 41.275 mm bore (85.725×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3880/3820 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 3880 and 3820; use undercut shoulders so the rings seat on the face, not on a radius.", "ABMA makes the 41.275×85.725 mm envelope interchangeable, not the ratings: NTN prints 116/132 kN for this execution and another make of the same number can differ in roller complement.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 116/132 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3880/3820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3880/3820?", "a": "4T-3880/3820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 85.725 mm outside diameter and 30.162 mm assembled width T (3.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 116 kN, C0 132 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 814 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3880/3820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3880 cone or the 3820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 116/132 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3880/3820 and a metric ISO 355 tapered bearing?", "a": "4T-3880/3820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×85.725×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3880/3820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3880/3820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3880/3820 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3880/3820 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3880", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3880-3820", "3880-3820", "4T-3880-3820" ], "locale_variants": {} }, { "sku": "3576-3525", "brand": "NTN", "manufacturer_designation": "NTN 4T-3576/3525", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 87.312, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 104, "static_load_kN": 117, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5900, "weight_g": 830, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-3576/3525 at 41.275 mm bore (1.625 in), 87.312 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 4,400 r/min and an oil ceiling of 5,900 r/min. Cone and cup of 4T-3576/3525 are separately stocked parts: a worn 3525 cup can be replaced against the existing 3576 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 4,400 r/min is the mechanical ceiling for 4T-3576/3525, oil 5,900 r/min with circulating oil — a 1,500 r/min margin at this size. The printed 104/117 kN ratings belong to the assembled 3576+3525 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-3576/3525 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3576/3525.", "The pure-numeric inch family at 41.275 mm bore (87.312×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3576/3525 reference at purchase.", "An unloaded 4T-3576/3525 near 4,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 41.275 mm is 1.625 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-3576/3525 sets have no seals: a hub or gearbox needs external sealing or the 4,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 104/117 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3576/3525; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3576/3525?", "a": "4T-3576/3525 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 87.312 mm outside diameter and 30.162 mm assembled width T (3.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 104 kN, C0 117 kN, grease limiting speed 4,400 r/min, oil speed 5,900 r/min, mass about 830 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3576/3525 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3576 cone or the 3525 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 104/117 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3576/3525 and a metric ISO 355 tapered bearing?", "a": "4T-3576/3525 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×87.312×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3576/3525 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3576/3525 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3576/3525 list two speeds, 4,400 and 5,900 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3576/3525 at 5,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3576", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3576-3525", "3576-3525", "4T-3576-3525" ], "locale_variants": {} }, { "sku": "HM803145-HM803110", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM803145/HM803110", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 88.9, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 104, "static_load_kN": 125, "limiting_speed_rpm": 4300, "max_rpm": 4300, "speed_oil_rpm": 5800, "weight_g": 902, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM803145/HM803110 is the NTN 4T catalogue entry for a 41.275×88.9×30.162 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HM803145 sits in the heavy-medium HM family. Imperial cross-check for the drawing: 41.275×88.9×30.162 mm converts to 1.625 × 3.5 × 1.187 in; the ABMA envelope swaps with like-numbered inch parts but the 104/125 kN ratings are NTN-specific. Cup-side note for HM803110: within the heavy-medium HM family tables the HM803145 cone is listed against several cup options, and it is the cup that fixes the 88.9 mm OD and the 30.162 mm assembled width — quote the full HM803145/HM803110 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-HM803145/HM803110 run near 4,300 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM803145/HM803110.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 41.275 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Quote the full HM803145/HM803110 pair at ordering: the HM803145 cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "ABMA makes the 41.275×88.9 mm envelope interchangeable, not the ratings: NTN prints 104/125 kN for this execution and another make of the same number can differ in roller complement.", "The 104/125 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM803145/HM803110; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM803145/HM803110?", "a": "4T-HM803145/HM803110 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 88.9 mm outside diameter and 30.162 mm assembled width T (3.5 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 104 kN, C0 125 kN, grease limiting speed 4,300 r/min, oil speed 5,800 r/min, mass about 902 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM803145/HM803110 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM803145 cone or the HM803110 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 104/125 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM803145/HM803110 and a metric ISO 355 tapered bearing?", "a": "4T-HM803145/HM803110 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×88.9×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM803145/HM803110 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM803145/HM803110 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM803145/HM803110 list two speeds, 4,300 and 5,800 r/min?", "a": "The lower figure, 4,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM803145/HM803110 at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM803145", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm803145-hm803110", "hm803145-hm803110", "HM803145-HM803110", "4T-HM803145-HM803110" ], "locale_variants": {} }, { "sku": "4388-4335", "brand": "NTN", "manufacturer_designation": "NTN 4T-4388/4335", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 90.488, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 151, "static_load_kN": 175, "limiting_speed_rpm": 4300, "max_rpm": 4300, "speed_oil_rpm": 5800, "weight_g": 1260, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 41.275 mm carrying combined radial and thrust load, NTN lists 4T-4388/4335, a single-row 4T tapered roller set of 151 kN C and 175 kN C0 inside the 90.488 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 4388 identifies the cone of 41.275 mm (1.625 in) bore by catalogue lookup, and 4335 fixes the 90.488 mm OD. Speed planning uses both catalogue columns: grease 4,300 r/min is the mechanical ceiling for 4T-4388/4335, oil 5,800 r/min with circulating oil — a 1,500 r/min margin at this size. The printed 151/175 kN ratings belong to the assembled 4388+4335 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 4388 cone and 4335 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-4388/4335.", "The pure-numeric inch family at 41.275 mm bore (90.488×39.688 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 4388/4335 reference at purchase.", "Inch and metric bores collide on paper — 41.275 mm is 1.625 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "An unloaded 4T-4388/4335 near 4,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Grease packs must leave free volume inside the 39.688 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,800 r/min raises temperature and destroys the setting.", "The 151/175 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-4388/4335; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-4388/4335?", "a": "4T-4388/4335 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 90.488 mm outside diameter and 39.688 mm assembled width T (3.563 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 151 kN, C0 175 kN, grease limiting speed 4,300 r/min, oil speed 5,800 r/min, mass about 1260 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-4388/4335 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 4388 cone or the 4335 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 151/175 kN ratings change with the cup." }, { "q": "What is the difference between 4T-4388/4335 and a metric ISO 355 tapered bearing?", "a": "4T-4388/4335 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×90.488×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-4388/4335 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 4388/4335 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-4388/4335 list two speeds, 4,300 and 5,800 r/min?", "a": "The lower figure, 4,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-4388/4335 at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "4388", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-4388-4335", "4388-4335", "4T-4388-4335" ], "locale_variants": {} }, { "sku": "M903345-M903310", "brand": "NTN", "manufacturer_designation": "NTN 4T-M903345/M903310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 92.075, "B_mm": 26.195, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 80.5, "static_load_kN": 81.5, "limiting_speed_rpm": 3800, "max_rpm": 3800, "speed_oil_rpm": 5000, "weight_g": 758, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 41.275 mm carrying combined radial and thrust load, NTN lists 4T-M903345/M903310, a single-row 4T tapered roller set of 80.5 kN C and 81.5 kN C0 inside the 92.075 mm OD cup. Cone and cup of 4T-M903345/M903310 are separately stocked parts: a worn M903310 cup can be replaced against the existing M903345 cone, provided the new cup carries the identical reference — pairing across references changes the 26.195 mm assembled width and the rating. The 25.4 mm radial section over the 41.275 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for M903310: within the medium M family tables the M903345 cone is listed against several cup options, and it is the cup that fixes the 92.075 mm OD and the 26.195 mm assembled width — quote the full M903345/M903310 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 41.275 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-M903345/M903310.", "The medium M family at 41.275 mm bore (92.075×26.195 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full M903345/M903310 reference at purchase.", "An unloaded 4T-M903345/M903310 near 3,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Open 4T-M903345/M903310 sets have no seals: a hub or gearbox needs external sealing or the 3,800 r/min grease figure is meaningless once water reaches the cone rib.", "Fit selection follows the rotating ring: a rotating cone on a 41.275 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 80.5/81.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-M903345/M903310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-M903345/M903310?", "a": "4T-M903345/M903310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 92.075 mm outside diameter and 26.195 mm assembled width T (3.625 × 1.031 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 80.5 kN, C0 81.5 kN, grease limiting speed 3,800 r/min, oil speed 5,000 r/min, mass about 758 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-M903345/M903310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the M903345 cone or the M903310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 80.5/81.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-M903345/M903310 and a metric ISO 355 tapered bearing?", "a": "4T-M903345/M903310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×92.075×26.195 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-M903345/M903310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare M903345/M903310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-M903345/M903310 list two speeds, 3,800 and 5,000 r/min?", "a": "The lower figure, 3,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-M903345/M903310 at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "M903345", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-m903345-m903310", "m903345-m903310", "M903345-M903310", "4T-M903345-M903310" ], "locale_variants": {} }, { "sku": "46162-46368", "brand": "NTN", "manufacturer_designation": "NTN 4T-46162/46368", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 93.662, "B_mm": 31.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 115, "static_load_kN": 131, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 1090, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-46162/46368 is the NTN 4T catalogue entry for a 41.275×93.662×31.75 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 46162 sits in the pure-numeric inch family. Selection: C 115 kN against C0 131 kN gives a C0/C ratio of 1.14 for the 41.275 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 46368: within the pure-numeric inch family tables the 46162 cone is listed against several cup options, and it is the cup that fixes the 93.662 mm OD and the 31.75 mm assembled width — quote the full 46162/46368 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-46162/46368 run near 4,100 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-46162/46368.", "The pure-numeric inch family at 41.275 mm bore (93.662×31.75 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 46162/46368 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 41.275 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 41.275×93.662 mm envelope interchangeable, not the ratings: NTN prints 115/131 kN for this execution and another make of the same number can differ in roller complement.", "Shaft and housing fillets must clear the ring chamfers of 46162 and 46368; use undercut shoulders so the rings seat on the face, not on a radius.", "The 115/131 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-46162/46368; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-46162/46368?", "a": "4T-46162/46368 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 93.662 mm outside diameter and 31.75 mm assembled width T (3.687 × 1.25 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 115 kN, C0 131 kN, grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 1090 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-46162/46368 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 46162 cone or the 46368 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 115/131 kN ratings change with the cup." }, { "q": "What is the difference between 4T-46162/46368 and a metric ISO 355 tapered bearing?", "a": "4T-46162/46368 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×93.662×31.75 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-46162/46368 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 46162/46368 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-46162/46368 list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-46162/46368 at 5,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "46162", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-46162-46368", "46162-46368", "4T-46162-46368" ], "locale_variants": {} }, { "sku": "53162-53375", "brand": "NTN", "manufacturer_designation": "NTN 4T-53162/53375", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 95.25, "B_mm": 30.958, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 91.5, "static_load_kN": 92, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 974, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-53162/53375 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-53162/53375 are separately stocked parts: a worn 53375 cup can be replaced against the existing 53162 cone, provided the new cup carries the identical reference — pairing across references changes the 30.958 mm assembled width and the rating. Selection: C 91.5 kN against C0 92 kN gives a C0/C ratio of 1.01 for the 41.275 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 91.5/92 kN ratings belong to the assembled 53162+53375 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-53162/53375 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-53162/53375.", "The pure-numeric inch family at 41.275 mm bore (95.25×30.958 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 53162/53375 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 41.275 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 41.275×95.25 mm envelope interchangeable, not the ratings: NTN prints 91.5/92 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 53162/53375 pair at ordering: the 53162 cone also ships against sibling cups, and a cup from another reference changes the 30.958 mm assembled width and the rating.", "The 91.5/92 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-53162/53375; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-53162/53375?", "a": "4T-53162/53375 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 95.25 mm outside diameter and 30.958 mm assembled width T (3.75 × 1.219 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 91.5 kN, C0 92 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 974 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-53162/53375 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 53162 cone or the 53375 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 91.5/92 kN ratings change with the cup." }, { "q": "What is the difference between 4T-53162/53375 and a metric ISO 355 tapered bearing?", "a": "4T-53162/53375 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×95.25×30.958 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-53162/53375 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 53162/53375 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-53162/53375 list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-53162/53375 at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "53162", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-53162-53375", "53162-53375", "4T-53162-53375" ], "locale_variants": {} }, { "sku": "HM804840-HM804810", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM804840/HM804810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 95.25, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 120, "static_load_kN": 147, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 1080, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.625 in (41.275 mm) shaft position as 4T-HM804840/HM804810: cone HM804840, cup HM804810, profiled rollers and a pressed-steel cage, rated 120 kN basic dynamic and 147 kN static. Reading the designation: 4T-HM804840/HM804810 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the heavy-medium HM family lettering ties the pair to its boundary plan. Speed planning uses both catalogue columns: grease 4,000 r/min is the mechanical ceiling for 4T-HM804840/HM804810, oil 5,300 r/min with circulating oil — a 1,300 r/min margin at this size. Cup-side note for HM804810: within the heavy-medium HM family tables the HM804840 cone is listed against several cup options, and it is the cup that fixes the 95.25 mm OD and the 30.162 mm assembled width — quote the full HM804840/HM804810 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-HM804840/HM804810 run near 4,000 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM804840/HM804810.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 41.275 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Never drive the 95.25 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Quote the full HM804840/HM804810 pair at ordering: the HM804840 cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "ABMA makes the 41.275×95.25 mm envelope interchangeable, not the ratings: NTN prints 120/147 kN for this execution and another make of the same number can differ in roller complement.", "The 120/147 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM804840/HM804810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM804840/HM804810?", "a": "4T-HM804840/HM804810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 95.25 mm outside diameter and 30.162 mm assembled width T (3.75 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 120 kN, C0 147 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 1080 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM804840/HM804810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM804840 cone or the HM804810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 120/147 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM804840/HM804810 and a metric ISO 355 tapered bearing?", "a": "4T-HM804840/HM804810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×95.25×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM804840/HM804810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM804840/HM804810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM804840/HM804810 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM804840/HM804810 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM804840", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm804840-hm804810", "hm804840-hm804810", "HM804840-HM804810", "4T-HM804840-HM804810" ], "locale_variants": {} }, { "sku": "HM903245-HM903210", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM903245/HM903210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 41.275, "D_mm": 95.25, "B_mm": 30.958, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 107, "static_load_kN": 116, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-HM903245/HM903210 denotes the heavy-medium HM family of NTN inch tapered roller bearings — cone HM903245 and cup HM903210 delivered as a matched, separable pair of 41.275 mm bore and 95.25 mm outside diameter. Cone and cup of 4T-HM903245/HM903210 are separately stocked parts: a worn HM903210 cup can be replaced against the existing HM903245 cone, provided the new cup carries the identical reference — pairing across references changes the 30.958 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 3,700 r/min is the mechanical ceiling for 4T-HM903245/HM903210, oil 4,900 r/min with circulating oil — a 1,200 r/min margin at this size. The printed 107/116 kN ratings belong to the assembled HM903245+HM903210 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-HM903245/HM903210 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 41.275 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM903245/HM903210.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 41.275 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Open 4T-HM903245/HM903210 sets have no seals: a hub or gearbox needs external sealing or the 3,700 r/min grease figure is meaningless once water reaches the cone rib.", "Shaft and housing fillets must clear the ring chamfers of HM903245 and HM903210; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 41.275 mm is 1.625 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 107/116 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM903245/HM903210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM903245/HM903210?", "a": "4T-HM903245/HM903210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 41.275 mm bore (1.625 in), 95.25 mm outside diameter and 30.958 mm assembled width T (3.75 × 1.219 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 107 kN, C0 116 kN, grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 1050 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM903245/HM903210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM903245 cone or the HM903210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 107/116 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM903245/HM903210 and a metric ISO 355 tapered bearing?", "a": "4T-HM903245/HM903210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 41.275×95.25×30.958 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM903245/HM903210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM903245/HM903210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM903245/HM903210 list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM903245/HM903210 at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM903245", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm903245-hm903210", "hm903245-hm903210", "HM903245-HM903210", "4T-HM903245-HM903210" ], "locale_variants": {} }, { "sku": "4395-4335", "brand": "NTN", "manufacturer_designation": "NTN 4T-4395/4335", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 42.07, "D_mm": 90.488, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 151, "static_load_kN": 175, "limiting_speed_rpm": 4300, "max_rpm": 4300, "speed_oil_rpm": 5800, "weight_g": 1240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-4395/4335 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 4395 identifies the cone of 42.07 mm (1.656 in) bore by catalogue lookup, and 4335 fixes the 90.488 mm OD. Imperial cross-check for the drawing: 42.07×90.488×39.688 mm converts to 1.656 × 3.563 × 1.563 in; the ABMA envelope swaps with like-numbered inch parts but the 151/175 kN ratings are NTN-specific. The printed 151/175 kN ratings belong to the assembled 4395+4335 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-4395/4335; reverse the fit logic when the cup rotates.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 42.07 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-4395/4335.", "The pure-numeric inch family at 42.07 mm bore (90.488×39.688 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 4395/4335 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 42.07 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 42.07×90.488 mm envelope interchangeable, not the ratings: NTN prints 151/175 kN for this execution and another make of the same number can differ in roller complement.", "Replacing one half of an adjusted pair without resetting end play negates the 39.688 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 151/175 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-4395/4335; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-4395/4335?", "a": "4T-4395/4335 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 42.07 mm bore (1.656 in), 90.488 mm outside diameter and 39.688 mm assembled width T (3.563 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 151 kN, C0 175 kN, grease limiting speed 4,300 r/min, oil speed 5,800 r/min, mass about 1240 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-4395/4335 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 4395 cone or the 4335 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 151/175 kN ratings change with the cup." }, { "q": "What is the difference between 4T-4395/4335 and a metric ISO 355 tapered bearing?", "a": "4T-4395/4335 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 42.07×90.488×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-4395/4335 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 4395/4335 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-4395/4335 list two speeds, 4,300 and 5,800 r/min?", "a": "The lower figure, 4,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-4395/4335 at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "4395", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-4395-4335", "4395-4335", "4T-4395-4335" ], "locale_variants": {} }, { "sku": "22780-22720", "brand": "NTN", "manufacturer_designation": "NTN 4T-22780/22720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 42.862, "D_mm": 82.55, "B_mm": 26.195, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 83.5, "static_load_kN": 97, "limiting_speed_rpm": 4600, "max_rpm": 4600, "speed_oil_rpm": 6100, "weight_g": 618, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-22780/22720 is the NTN 4T catalogue entry for a 42.862×82.55×26.195 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 22780 sits in the pure-numeric inch family. Catalogue mass of the 4T-22780/22720 cone-plus-cup set is 618 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 83.5/97 kN ratings belong to the assembled 22780+22720 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-22780/22720 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 42.862 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-22780/22720.", "The pure-numeric inch family at 42.862 mm bore (82.55×26.195 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 22780/22720 reference at purchase.", "Grease packs must leave free volume inside the 26.195 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,100 r/min raises temperature and destroys the setting.", "Never drive the 82.55 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 42.862×82.55 mm envelope interchangeable, not the ratings: NTN prints 83.5/97 kN for this execution and another make of the same number can differ in roller complement.", "The 83.5/97 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-22780/22720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-22780/22720?", "a": "4T-22780/22720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 42.862 mm bore (1.687 in), 82.55 mm outside diameter and 26.195 mm assembled width T (3.25 × 1.031 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 83.5 kN, C0 97 kN, grease limiting speed 4,600 r/min, oil speed 6,100 r/min, mass about 618 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-22780/22720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 22780 cone or the 22720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 83.5/97 kN ratings change with the cup." }, { "q": "What is the difference between 4T-22780/22720 and a metric ISO 355 tapered bearing?", "a": "4T-22780/22720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 42.862×82.55×26.195 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-22780/22720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 22780/22720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-22780/22720 list two speeds, 4,600 and 6,100 r/min?", "a": "The lower figure, 4,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-22780/22720 at 6,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "22780", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-22780-22720", "22780-22720", "4T-22780-22720" ], "locale_variants": {} }, { "sku": "25578-25520", "brand": "NTN", "manufacturer_designation": "NTN 4T-25578/25520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 42.862, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 84.5, "static_load_kN": 98, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 584, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 42.862 mm carrying combined radial and thrust load, NTN lists 4T-25578/25520, a single-row 4T tapered roller set of 84.5 kN C and 98 kN C0 inside the 82.931 mm OD cup. Cone and cup of 4T-25578/25520 are separately stocked parts: a worn 25520 cup can be replaced against the existing 25578 cone, provided the new cup carries the identical reference — pairing across references changes the 23.812 mm assembled width and the rating. The 20.0 mm radial section over the 42.862 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 25520: within the pure-numeric inch family tables the 25578 cone is listed against several cup options, and it is the cup that fixes the 82.931 mm OD and the 23.812 mm assembled width — quote the full 25578/25520 pair, never the cone alone. Fillet radii must clear the chamfers of the 25578 cone and 25520 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 42.862 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25578/25520.", "The pure-numeric inch family at 42.862 mm bore (82.931×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25578/25520 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 42.862 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 42.862×82.931 mm envelope interchangeable, not the ratings: NTN prints 84.5/98 kN for this execution and another make of the same number can differ in roller complement.", "Never drive the 82.931 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 84.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25578/25520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25578/25520?", "a": "4T-25578/25520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 42.862 mm bore (1.687 in), 82.931 mm outside diameter and 23.812 mm assembled width T (3.265 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 84.5 kN, C0 98 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 584 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25578/25520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25578 cone or the 25520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 84.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25578/25520 and a metric ISO 355 tapered bearing?", "a": "4T-25578/25520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 42.862×82.931×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25578/25520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25578/25520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25578/25520 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25578/25520 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25578", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25578-25520", "25578-25520", "4T-25578-25520" ], "locale_variants": {} }, { "sku": "3579-3525", "brand": "NTN", "manufacturer_designation": "NTN 4T-3579/3525", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 42.862, "D_mm": 87.312, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 104, "static_load_kN": 117, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5900, "weight_g": 807, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.687 in (42.862 mm) shaft position as 4T-3579/3525: cone 3579, cup 3525, profiled rollers and a pressed-steel cage, rated 104 kN basic dynamic and 117 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 3579 sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-3579/3525 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 104/117 kN ratings belong to the assembled 3579+3525 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-3579/3525 run near 4,400 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 42.862 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3579/3525.", "The pure-numeric inch family at 42.862 mm bore (87.312×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3579/3525 reference at purchase.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-3579/3525 sets have no seals: a hub or gearbox needs external sealing or the 4,400 r/min grease figure is meaningless once water reaches the cone rib.", "Open 4T-3579/3525 sets have no seals: a hub or gearbox needs external sealing or the 4,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 104/117 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3579/3525; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3579/3525?", "a": "4T-3579/3525 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 42.862 mm bore (1.687 in), 87.312 mm outside diameter and 30.162 mm assembled width T (3.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 104 kN, C0 117 kN, grease limiting speed 4,400 r/min, oil speed 5,900 r/min, mass about 807 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3579/3525 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3579 cone or the 3525 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 104/117 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3579/3525 and a metric ISO 355 tapered bearing?", "a": "4T-3579/3525 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 42.862×87.312×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3579/3525 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3579/3525 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3579/3525 list two speeds, 4,400 and 5,900 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3579/3525 at 5,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3579", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3579-3525", "3579-3525", "4T-3579-3525" ], "locale_variants": {} }, { "sku": "26884-26822", "brand": "NTN", "manufacturer_designation": "NTN 4T-26884/26822", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 42.875, "D_mm": 79.375, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 97.5, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 511, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.688 in (42.875 mm) shaft position as 4T-26884/26822: cone 26884, cup 26822, profiled rollers and a pressed-steel cage, rated 85 kN basic dynamic and 97.5 kN static. Reading the designation: 4T-26884/26822 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 2.0 kN of dynamic capacity per millimetre of bore summarises the 85 kN rating over the 42.875 mm bore — sanity-check any interchange candidate against this ratio and the 23.812 mm T. Housing fitment sequence for 4T-26884/26822: press the 26822 cup square into the 79.375 mm seat first, then bring the 26884 cone (on its 42.875 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-26884/26822; reverse the fit logic when the cup rotates.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 42.875 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-26884/26822.", "The pure-numeric inch family at 42.875 mm bore (79.375×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 26884/26822 reference at purchase.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "ABMA makes the 42.875×79.375 mm envelope interchangeable, not the ratings: NTN prints 85/97.5 kN for this execution and another make of the same number can differ in roller complement.", "Replacing one half of an adjusted pair without resetting end play negates the 23.812 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 85/97.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-26884/26822; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-26884/26822?", "a": "4T-26884/26822 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 42.875 mm bore (1.688 in), 79.375 mm outside diameter and 23.812 mm assembled width T (3.125 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 97.5 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 511 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-26884/26822 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 26884 cone or the 26822 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/97.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-26884/26822 and a metric ISO 355 tapered bearing?", "a": "4T-26884/26822 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 42.875×79.375×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-26884/26822 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 26884/26822 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-26884/26822 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-26884/26822 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "26884", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-26884-26822", "26884-26822", "4T-26884-26822" ], "locale_variants": {} }, { "sku": "25577-25520-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-25577/25520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 42.875, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 84.5, "static_load_kN": 98, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 582, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 42.875 mm carrying combined radial and thrust load, NTN lists 4T-25577/25520, a single-row 4T tapered roller set of 84.5 kN C and 98 kN C0 inside the 82.931 mm OD cup. Cone and cup of 4T-25577/25520 are separately stocked parts: a worn 25520 cup can be replaced against the existing 25577 cone, provided the new cup carries the identical reference — pairing across references changes the 23.812 mm assembled width and the rating. Grease relubrication at the 4,500 r/min limiting speed targets the cone-rib contact; sustaining 6,000 r/min needs an oil supply directed at the large roller ends. Cup-side note for 25520: within the pure-numeric inch family tables the 25577 cone is listed against several cup options, and it is the cup that fixes the 82.931 mm OD and the 23.812 mm assembled width — quote the full 25577/25520 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-25577/25520, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 42.875 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25577/25520.", "The pure-numeric inch family at 42.875 mm bore (82.931×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25577/25520 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 42.875 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "An unloaded 4T-25577/25520 near 4,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "ABMA makes the 42.875×82.931 mm envelope interchangeable, not the ratings: NTN prints 84.5/98 kN for this execution and another make of the same number can differ in roller complement.", "The 84.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25577/25520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25577/25520?", "a": "4T-25577/25520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 42.875 mm bore (1.688 in), 82.931 mm outside diameter and 23.812 mm assembled width T (3.265 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 84.5 kN, C0 98 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 582 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25577/25520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25577 cone or the 25520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 84.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25577/25520 and a metric ISO 355 tapered bearing?", "a": "4T-25577/25520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 42.875×82.931×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25577/25520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25577/25520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25577/25520 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25577/25520 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25577-25520", "equiv_brand": "SKF", "level": "partial", "note": "Same 42.875×82.931×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25577-25523", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25577-25520", "25577-25520", "4T-25577-25520", "25577-25520-NTN" ], "locale_variants": {} }, { "sku": "12175-12303", "brand": "NTN", "manufacturer_designation": "NTN 4T-12175/12303", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 76.992, "B_mm": 17.462, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 48.5, "static_load_kN": 54, "limiting_speed_rpm": 4700, "max_rpm": 4700, "speed_oil_rpm": 6300, "weight_g": 308, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-12175/12303 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 12175 and cup 12303 delivered as a matched, separable pair of 44.45 mm bore and 76.992 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 12175 identifies the cone of 44.45 mm (1.75 in) bore by catalogue lookup, and 12303 fixes the 76.992 mm OD. Speed planning uses both catalogue columns: grease 4,700 r/min is the mechanical ceiling for 4T-12175/12303, oil 6,300 r/min with circulating oil — a 1,600 r/min margin at this size. Housing fitment sequence for 4T-12175/12303: press the 12303 cup square into the 76.992 mm seat first, then bring the 12175 cone (on its 44.45 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Contact-pattern check with marking blue: a pattern biased to one roller end means the 44.45 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-12175/12303.", "The pure-numeric inch family at 44.45 mm bore (76.992×17.462 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 12175/12303 reference at purchase.", "Quote the full 12175/12303 pair at ordering: the 12175 cone also ships against sibling cups, and a cup from another reference changes the 17.462 mm assembled width and the rating.", "Quote the full 12175/12303 pair at ordering: the 12175 cone also ships against sibling cups, and a cup from another reference changes the 17.462 mm assembled width and the rating.", "Do not confuse T (17.462 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 48.5/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-12175/12303; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-12175/12303?", "a": "4T-12175/12303 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 76.992 mm outside diameter and 17.462 mm assembled width T (3.031 × 0.687 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 48.5 kN, C0 54 kN, grease limiting speed 4,700 r/min, oil speed 6,300 r/min, mass about 308 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-12175/12303 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 12175 cone or the 12303 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 48.5/54 kN ratings change with the cup." }, { "q": "What is the difference between 4T-12175/12303 and a metric ISO 355 tapered bearing?", "a": "4T-12175/12303 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×76.992×17.462 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-12175/12303 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 12175/12303 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-12175/12303 list two speeds, 4,700 and 6,300 r/min?", "a": "The lower figure, 4,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-12175/12303 at 6,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "12175", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-12175-12303", "12175-12303", "4T-12175-12303" ], "locale_variants": {} }, { "sku": "18685-18620", "brand": "NTN", "manufacturer_designation": "NTN 4T-18685/18620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 79.375, "B_mm": 17.462, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 50.5, "static_load_kN": 56, "limiting_speed_rpm": 4600, "max_rpm": 4600, "speed_oil_rpm": 6200, "weight_g": 347, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-18685/18620 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 44.45×79.375×17.462 mm (assembled width T), for a shaft of about 44.45 mm (1.75 in). Reading the designation: 4T-18685/18620 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 4,600 r/min limiting speed targets the cone-rib contact; sustaining 6,200 r/min needs an oil supply directed at the large roller ends. Cup-side note for 18620: within the pure-numeric inch family tables the 18685 cone is listed against several cup options, and it is the cup that fixes the 79.375 mm OD and the 17.462 mm assembled width — quote the full 18685/18620 pair, never the cone alone. Running clearance of 4T-18685/18620 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-18685/18620.", "The pure-numeric inch family at 44.45 mm bore (79.375×17.462 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 18685/18620 reference at purchase.", "Do not confuse T (17.462 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Quote the full 18685/18620 pair at ordering: the 18685 cone also ships against sibling cups, and a cup from another reference changes the 17.462 mm assembled width and the rating.", "An unloaded 4T-18685/18620 near 4,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 50.5/56 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-18685/18620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-18685/18620?", "a": "4T-18685/18620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 79.375 mm outside diameter and 17.462 mm assembled width T (3.125 × 0.687 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 50.5 kN, C0 56 kN, grease limiting speed 4,600 r/min, oil speed 6,200 r/min, mass about 347 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-18685/18620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 18685 cone or the 18620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 50.5/56 kN ratings change with the cup." }, { "q": "What is the difference between 4T-18685/18620 and a metric ISO 355 tapered bearing?", "a": "4T-18685/18620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×79.375×17.462 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-18685/18620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 18685/18620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-18685/18620 list two speeds, 4,600 and 6,200 r/min?", "a": "The lower figure, 4,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-18685/18620 at 6,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "18685", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-18685-18620", "18685-18620", "4T-18685-18620" ], "locale_variants": {} }, { "sku": "25580-25520-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-25580/25520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 84.5, "static_load_kN": 98, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 560, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-25580/25520 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 25580 and cup 25520 delivered as a matched, separable pair of 44.45 mm bore and 82.931 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 25580 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 4,500 r/min is the mechanical ceiling for 4T-25580/25520, oil 6,000 r/min with circulating oil — a 1,500 r/min margin at this size. The printed 84.5/98 kN ratings belong to the assembled 25580+25520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-25580/25520; reverse the fit logic when the cup rotates.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25580/25520.", "The pure-numeric inch family at 44.45 mm bore (82.931×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25580/25520 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 25580 and 25520; use undercut shoulders so the rings seat on the face, not on a radius.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-25580/25520 sets have no seals: a hub or gearbox needs external sealing or the 4,500 r/min grease figure is meaningless once water reaches the cone rib.", "The 84.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25580/25520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25580/25520?", "a": "4T-25580/25520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 82.931 mm outside diameter and 23.812 mm assembled width T (3.265 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 84.5 kN, C0 98 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 560 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25580/25520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25580 cone or the 25520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 84.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25580/25520 and a metric ISO 355 tapered bearing?", "a": "4T-25580/25520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×82.931×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25580/25520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25580/25520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25580/25520 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25580/25520 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25580-25520", "equiv_brand": "SKF", "level": "partial", "note": "Same 44.45×82.931×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25580-25522", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25580-25523", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25580-25520", "25580-25520", "4T-25580-25520", "25580-25520-NTN" ], "locale_variants": {} }, { "sku": "25582-25520", "brand": "NTN", "manufacturer_designation": "NTN 4T-25582/25520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 84.5, "static_load_kN": 98, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 564, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 44.45 mm carrying combined radial and thrust load, NTN lists 4T-25582/25520, a single-row 4T tapered roller set of 84.5 kN C and 98 kN C0 inside the 82.931 mm OD cup. Reading the designation: 4T-25582/25520 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Contact-angle geometry of the pure-numeric inch family gives 4T-25582/25520 its radial/axial load split — at 84.5/98 kN the static rating is about 1.16× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 25520: within the pure-numeric inch family tables the 25582 cone is listed against several cup options, and it is the cup that fixes the 82.931 mm OD and the 23.812 mm assembled width — quote the full 25582/25520 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-25582/25520 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25582/25520.", "The pure-numeric inch family at 44.45 mm bore (82.931×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25582/25520 reference at purchase.", "Grease packs must leave free volume inside the 23.812 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,000 r/min raises temperature and destroys the setting.", "Grease packs must leave free volume inside the 23.812 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,000 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 44.45 mm is 1.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 84.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25582/25520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25582/25520?", "a": "4T-25582/25520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 82.931 mm outside diameter and 23.812 mm assembled width T (3.265 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 84.5 kN, C0 98 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 564 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25582/25520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25582 cone or the 25520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 84.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25582/25520 and a metric ISO 355 tapered bearing?", "a": "4T-25582/25520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×82.931×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25582/25520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25582/25520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25582/25520 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25582/25520 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25582", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25582-25520", "25582-25520", "4T-25582-25520" ], "locale_variants": {} }, { "sku": "3578-3520", "brand": "NTN", "manufacturer_designation": "NTN 4T-3578/3520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 84.138, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 104, "static_load_kN": 117, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5900, "weight_g": 701, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-3578/3520 at 44.45 mm bore (1.75 in), 84.138 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 4,400 r/min and an oil ceiling of 5,900 r/min. Cone and cup of 4T-3578/3520 are separately stocked parts: a worn 3520 cup can be replaced against the existing 3578 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 4,400 r/min is the mechanical ceiling for 4T-3578/3520, oil 5,900 r/min with circulating oil — a 1,500 r/min margin at this size. The printed 104/117 kN ratings belong to the assembled 3578+3520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-3578/3520 run near 4,400 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3578/3520.", "The pure-numeric inch family at 44.45 mm bore (84.138×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3578/3520 reference at purchase.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "ABMA makes the 44.45×84.138 mm envelope interchangeable, not the ratings: NTN prints 104/117 kN for this execution and another make of the same number can differ in roller complement.", "Shaft and housing fillets must clear the ring chamfers of 3578 and 3520; use undercut shoulders so the rings seat on the face, not on a radius.", "The 104/117 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3578/3520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3578/3520?", "a": "4T-3578/3520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 84.138 mm outside diameter and 30.162 mm assembled width T (3.313 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 104 kN, C0 117 kN, grease limiting speed 4,400 r/min, oil speed 5,900 r/min, mass about 701 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3578/3520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3578 cone or the 3520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 104/117 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3578/3520 and a metric ISO 355 tapered bearing?", "a": "4T-3578/3520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×84.138×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3578/3520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3578/3520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3578/3520 list two speeds, 4,400 and 5,900 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3578/3520 at 5,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3578-3525", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-3578 paired with a different cup (3525): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3578-3520", "3578-3520", "4T-3578-3520" ], "locale_variants": {} }, { "sku": "355-354A", "brand": "NTN", "manufacturer_designation": "NTN 4T-355/354A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 85, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 77.5, "static_load_kN": 79.5, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5800, "weight_g": 511, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-355/354A is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 44.45×85×20.638 mm (assembled width T), for a shaft of about 44.45 mm (1.75 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 355 sits in the pure-numeric inch family. The 20.3 mm radial section over the 44.45 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-355/354A: press the 354A cup square into the 85 mm seat first, then bring the 355 cone (on its 44.45 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 44.45 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-355/354A.", "The pure-numeric inch family at 44.45 mm bore (85×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 355/354A reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 355 and 354A; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full 355/354A pair at ordering: the 355 cone also ships against sibling cups, and a cup from another reference changes the 20.638 mm assembled width and the rating.", "Inch and metric bores collide on paper — 44.45 mm is 1.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 77.5/79.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-355/354A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-355/354A?", "a": "4T-355/354A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 85 mm outside diameter and 20.638 mm assembled width T (3.346 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 79.5 kN, grease limiting speed 4,400 r/min, oil speed 5,800 r/min, mass about 511 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-355/354A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 355 cone or the 354A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 77.5/79.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-355/354A and a metric ISO 355 tapered bearing?", "a": "4T-355/354A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×85×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-355/354A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 355/354A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-355/354A list two speeds, 4,400 and 5,800 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-355/354A at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "355", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "355-354a", "4t-355-354a", "355-354A", "4T-355-354A" ], "locale_variants": {} }, { "sku": "3578-3525", "brand": "NTN", "manufacturer_designation": "NTN 4T-3578/3525", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 87.312, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 104, "static_load_kN": 117, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5900, "weight_g": 780, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.75 in (44.45 mm) shaft position as 4T-3578/3525: cone 3578, cup 3525, profiled rollers and a pressed-steel cage, rated 104 kN basic dynamic and 117 kN static. Cone and cup of 4T-3578/3525 are separately stocked parts: a worn 3525 cup can be replaced against the existing 3578 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Selection: C 104 kN against C0 117 kN gives a C0/C ratio of 1.13 for the 44.45 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 104/117 kN ratings belong to the assembled 3578+3525 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-3578/3525 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3578/3525.", "The pure-numeric inch family at 44.45 mm bore (87.312×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3578/3525 reference at purchase.", "Open 4T-3578/3525 sets have no seals: a hub or gearbox needs external sealing or the 4,400 r/min grease figure is meaningless once water reaches the cone rib.", "Fit selection follows the rotating ring: a rotating cone on a 44.45 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 3578/3525 pair at ordering: the 3578 cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "The 104/117 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3578/3525; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3578/3525?", "a": "4T-3578/3525 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 87.312 mm outside diameter and 30.162 mm assembled width T (3.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 104 kN, C0 117 kN, grease limiting speed 4,400 r/min, oil speed 5,900 r/min, mass about 780 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3578/3525 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3578 cone or the 3525 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 104/117 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3578/3525 and a metric ISO 355 tapered bearing?", "a": "4T-3578/3525 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×87.312×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3578/3525 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3578/3525 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3578/3525 list two speeds, 4,400 and 5,900 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3578/3525 at 5,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3578-3520", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-3578 paired with a different cup (3520): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3578-3525", "3578-3525", "4T-3578-3525" ], "locale_variants": {} }, { "sku": "HM803149-HM803110", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM803149/HM803110", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 88.9, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 104, "static_load_kN": 125, "limiting_speed_rpm": 4300, "max_rpm": 4300, "speed_oil_rpm": 5800, "weight_g": 850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-HM803149/HM803110 at 44.45 mm bore (1.75 in), 88.9 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 4,300 r/min and an oil ceiling of 5,800 r/min. Cone and cup of 4T-HM803149/HM803110 are separately stocked parts: a worn HM803110 cup can be replaced against the existing HM803149 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Catalogue mass of the 4T-HM803149/HM803110 cone-plus-cup set is 850 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-HM803149/HM803110: press the HM803110 cup square into the 88.9 mm seat first, then bring the HM803149 cone (on its 44.45 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 44.45 mm cone with an induction heater (max 120 °C) and press the 88.9 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM803149/HM803110.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 44.45 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,800 r/min raises temperature and destroys the setting.", "Open 4T-HM803149/HM803110 sets have no seals: a hub or gearbox needs external sealing or the 4,300 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 104/125 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM803149/HM803110; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM803149/HM803110?", "a": "4T-HM803149/HM803110 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 88.9 mm outside diameter and 30.162 mm assembled width T (3.5 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 104 kN, C0 125 kN, grease limiting speed 4,300 r/min, oil speed 5,800 r/min, mass about 850 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM803149/HM803110 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM803149 cone or the HM803110 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 104/125 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM803149/HM803110 and a metric ISO 355 tapered bearing?", "a": "4T-HM803149/HM803110 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×88.9×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM803149/HM803110 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM803149/HM803110 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM803149/HM803110 list two speeds, 4,300 and 5,800 r/min?", "a": "The lower figure, 4,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM803149/HM803110 at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM803149-110", "equiv_brand": "SKF", "level": "partial", "note": "Same 44.45×88.9×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm803149-hm803110", "hm803149-hm803110", "HM803149-HM803110", "4T-HM803149-HM803110" ], "locale_variants": {} }, { "sku": "3782-3720-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-3782/3720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 93.264, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 134, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 959, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 44.45 mm carrying combined radial and thrust load, NTN lists 4T-3782/3720, a single-row 4T tapered roller set of 113 kN C and 134 kN C0 inside the 93.264 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 3782 identifies the cone of 44.45 mm (1.75 in) bore by catalogue lookup, and 3720 fixes the 93.264 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-3782/3720 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-3782/3720: press the 3720 cup square into the 93.264 mm seat first, then bring the 3782 cone (on its 44.45 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-3782/3720 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3782/3720.", "The pure-numeric inch family at 44.45 mm bore (93.264×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3782/3720 reference at purchase.", "ABMA makes the 44.45×93.264 mm envelope interchangeable, not the ratings: NTN prints 113/134 kN for this execution and another make of the same number can differ in roller complement.", "Never drive the 93.264 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 44.45×93.264 mm envelope interchangeable, not the ratings: NTN prints 113/134 kN for this execution and another make of the same number can differ in roller complement.", "The 113/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3782/3720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3782/3720?", "a": "4T-3782/3720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 93.264 mm outside diameter and 30.162 mm assembled width T (3.672 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 134 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 959 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3782/3720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3782 cone or the 3720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3782/3720 and a metric ISO 355 tapered bearing?", "a": "4T-3782/3720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×93.264×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3782/3720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3782/3720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3782/3720 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3782/3720 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3782-3720", "equiv_brand": "SKF", "level": "partial", "note": "Same 44.45×93.264×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3782-3720", "3782-3720", "4T-3782-3720", "3782-3720-NTN" ], "locale_variants": {} }, { "sku": "46175-46368", "brand": "NTN", "manufacturer_designation": "NTN 4T-46175/46368", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 93.662, "B_mm": 31.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 115, "static_load_kN": 131, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 1040, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-46175/46368 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-46175/46368 are separately stocked parts: a worn 46368 cup can be replaced against the existing 46175 cone, provided the new cup carries the identical reference — pairing across references changes the 31.75 mm assembled width and the rating. The 2.6 kN of dynamic capacity per millimetre of bore summarises the 115 kN rating over the 44.45 mm bore — sanity-check any interchange candidate against this ratio and the 31.75 mm T. The printed 115/131 kN ratings belong to the assembled 46175+46368 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 44.45 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-46175/46368.", "The pure-numeric inch family at 44.45 mm bore (93.662×31.75 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 46175/46368 reference at purchase.", "Inch and metric bores collide on paper — 44.45 mm is 1.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 31.75 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,500 r/min raises temperature and destroys the setting.", "Open 4T-46175/46368 sets have no seals: a hub or gearbox needs external sealing or the 4,100 r/min grease figure is meaningless once water reaches the cone rib.", "The 115/131 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-46175/46368; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-46175/46368?", "a": "4T-46175/46368 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 93.662 mm outside diameter and 31.75 mm assembled width T (3.687 × 1.25 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 115 kN, C0 131 kN, grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 1040 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-46175/46368 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 46175 cone or the 46368 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 115/131 kN ratings change with the cup." }, { "q": "What is the difference between 4T-46175/46368 and a metric ISO 355 tapered bearing?", "a": "4T-46175/46368 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×93.662×31.75 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-46175/46368 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 46175/46368 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-46175/46368 list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-46175/46368 at 5,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "46175", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-46175-46368", "46175-46368", "4T-46175-46368" ], "locale_variants": {} }, { "sku": "33885-33821", "brand": "NTN", "manufacturer_designation": "NTN 4T-33885/33821", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 95.25, "B_mm": 27.783, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 119, "static_load_kN": 139, "limiting_speed_rpm": 3900, "max_rpm": 3900, "speed_oil_rpm": 5200, "weight_g": 986, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 44.45 mm carrying combined radial and thrust load, NTN lists 4T-33885/33821, a single-row 4T tapered roller set of 119 kN C and 139 kN C0 inside the 95.25 mm OD cup. Cone and cup of 4T-33885/33821 are separately stocked parts: a worn 33821 cup can be replaced against the existing 33885 cone, provided the new cup carries the identical reference — pairing across references changes the 27.783 mm assembled width and the rating. Grease relubrication at the 3,900 r/min limiting speed targets the cone-rib contact; sustaining 5,200 r/min needs an oil supply directed at the large roller ends. The printed 119/139 kN ratings belong to the assembled 33885+33821 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-33885/33821 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-33885/33821.", "The pure-numeric inch family at 44.45 mm bore (95.25×27.783 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 33885/33821 reference at purchase.", "Quote the full 33885/33821 pair at ordering: the 33885 cone also ships against sibling cups, and a cup from another reference changes the 27.783 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of 33885 and 33821; use undercut shoulders so the rings seat on the face, not on a radius.", "ABMA makes the 44.45×95.25 mm envelope interchangeable, not the ratings: NTN prints 119/139 kN for this execution and another make of the same number can differ in roller complement.", "The 119/139 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-33885/33821; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-33885/33821?", "a": "4T-33885/33821 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 95.25 mm outside diameter and 27.783 mm assembled width T (3.75 × 1.094 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 119 kN, C0 139 kN, grease limiting speed 3,900 r/min, oil speed 5,200 r/min, mass about 986 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-33885/33821 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 33885 cone or the 33821 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 119/139 kN ratings change with the cup." }, { "q": "What is the difference between 4T-33885/33821 and a metric ISO 355 tapered bearing?", "a": "4T-33885/33821 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×95.25×27.783 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-33885/33821 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 33885/33821 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-33885/33821 list two speeds, 3,900 and 5,200 r/min?", "a": "The lower figure, 3,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-33885/33821 at 5,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "33885", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-33885-33821", "33885-33821", "4T-33885-33821" ], "locale_variants": {} }, { "sku": "438-432", "brand": "NTN", "manufacturer_designation": "NTN 4T-438/432", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 95.25, "B_mm": 27.783, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 120, "static_load_kN": 129, "limiting_speed_rpm": 4200, "max_rpm": 4200, "speed_oil_rpm": 5600, "weight_g": 957, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-438/432 at 44.45 mm bore (1.75 in), 95.25 mm cup OD and 27.783 mm assembled T, with a grease limiting speed of 4,200 r/min and an oil ceiling of 5,600 r/min. Reading the designation: 4T-438/432 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 27.783 mm T of each 4T-438/432 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 432: within the pure-numeric inch family tables the 438 cone is listed against several cup options, and it is the cup that fixes the 95.25 mm OD and the 27.783 mm assembled width — quote the full 438/432 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-438/432; reverse the fit logic when the cup rotates.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-438/432.", "The pure-numeric inch family at 44.45 mm bore (95.25×27.783 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 438/432 reference at purchase.", "Never drive the 95.25 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Fit selection follows the rotating ring: a rotating cone on a 44.45 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 44.45 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 120/129 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-438/432; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-438/432?", "a": "4T-438/432 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 95.25 mm outside diameter and 27.783 mm assembled width T (3.75 × 1.094 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 120 kN, C0 129 kN, grease limiting speed 4,200 r/min, oil speed 5,600 r/min, mass about 957 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-438/432 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 438 cone or the 432 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 120/129 kN ratings change with the cup." }, { "q": "What is the difference between 4T-438/432 and a metric ISO 355 tapered bearing?", "a": "4T-438/432 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×95.25×27.783 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-438/432 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 438/432 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-438/432 list two speeds, 4,200 and 5,600 r/min?", "a": "The lower figure, 4,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-438/432 at 5,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "438", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-438-432", "438-432", "4T-438-432" ], "locale_variants": {} }, { "sku": "53177-53375", "brand": "NTN", "manufacturer_designation": "NTN 4T-53177/53375", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 95.25, "B_mm": 30.958, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 91.5, "static_load_kN": 92, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 930, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-53177/53375 at 44.45 mm bore (1.75 in), 95.25 mm cup OD and 30.958 mm assembled T, with a grease limiting speed of 3,700 r/min and an oil ceiling of 5,000 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 53177 sits in the pure-numeric inch family. Selection: C 91.5 kN against C0 92 kN gives a C0/C ratio of 1.01 for the 44.45 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 91.5/92 kN ratings belong to the assembled 53177+53375 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-53177/53375; reverse the fit logic when the cup rotates.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-53177/53375.", "The pure-numeric inch family at 44.45 mm bore (95.25×30.958 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 53177/53375 reference at purchase.", "Never drive the 95.25 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Fit selection follows the rotating ring: a rotating cone on a 44.45 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 44.45 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 91.5/92 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-53177/53375; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-53177/53375?", "a": "4T-53177/53375 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 95.25 mm outside diameter and 30.958 mm assembled width T (3.75 × 1.219 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 91.5 kN, C0 92 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 930 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-53177/53375 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 53177 cone or the 53375 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 91.5/92 kN ratings change with the cup." }, { "q": "What is the difference between 4T-53177/53375 and a metric ISO 355 tapered bearing?", "a": "4T-53177/53375 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×95.25×30.958 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-53177/53375 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 53177/53375 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-53177/53375 list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-53177/53375 at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "53177", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-53177-53375", "53177-53375", "4T-53177-53375" ], "locale_variants": {} }, { "sku": "HM804842-HM804810", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM804842/HM804810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 95.25, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 120, "static_load_kN": 147, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 1040, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM804842/HM804810 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 44.45×95.25×30.162 mm (assembled width T), for a shaft of about 44.45 mm (1.75 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HM804842 identifies the cone of 44.45 mm (1.75 in) bore by catalogue lookup, and HM804810 fixes the 95.25 mm OD. Grease relubrication at the 4,000 r/min limiting speed targets the cone-rib contact; sustaining 5,300 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-HM804842/HM804810: press the HM804810 cup square into the 95.25 mm seat first, then bring the HM804842 cone (on its 44.45 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-HM804842/HM804810 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM804842/HM804810.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 44.45 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "An unloaded 4T-HM804842/HM804810 near 4,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Never drive the 95.25 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 120/147 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM804842/HM804810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM804842/HM804810?", "a": "4T-HM804842/HM804810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 95.25 mm outside diameter and 30.162 mm assembled width T (3.75 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 120 kN, C0 147 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 1040 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM804842/HM804810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM804842 cone or the HM804810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 120/147 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM804842/HM804810 and a metric ISO 355 tapered bearing?", "a": "4T-HM804842/HM804810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×95.25×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM804842/HM804810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM804842/HM804810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM804842/HM804810 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM804842/HM804810 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM804842", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm804842-hm804810", "hm804842-hm804810", "HM804842-HM804810", "4T-HM804842-HM804810" ], "locale_variants": {} }, { "sku": "HM903249-HM903210", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM903249/HM903210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 95.25, "B_mm": 30.958, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 107, "static_load_kN": 116, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 999, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.75 in (44.45 mm) shaft position as 4T-HM903249/HM903210: cone HM903249, cup HM903210, profiled rollers and a pressed-steel cage, rated 107 kN basic dynamic and 116 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HM903249 sits in the heavy-medium HM family. The 2.4 kN of dynamic capacity per millimetre of bore summarises the 107 kN rating over the 44.45 mm bore — sanity-check any interchange candidate against this ratio and the 30.958 mm T. Cup-side note for HM903210: within the heavy-medium HM family tables the HM903249 cone is listed against several cup options, and it is the cup that fixes the 95.25 mm OD and the 30.958 mm assembled width — quote the full HM903249/HM903210 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-HM903249/HM903210 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM903249/HM903210.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 44.45 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Never drive the 95.25 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Inch and metric bores collide on paper — 44.45 mm is 1.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Never drive the 95.25 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 107/116 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM903249/HM903210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM903249/HM903210?", "a": "4T-HM903249/HM903210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 95.25 mm outside diameter and 30.958 mm assembled width T (3.75 × 1.219 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 107 kN, C0 116 kN, grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 999 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM903249/HM903210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM903249 cone or the HM903210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 107/116 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM903249/HM903210 and a metric ISO 355 tapered bearing?", "a": "4T-HM903249/HM903210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×95.25×30.958 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM903249/HM903210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM903249/HM903210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM903249/HM903210 list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM903249/HM903210 at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM903249-210", "equiv_brand": "SKF", "level": "partial", "note": "Same 44.45×95.25×30.958 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm903249-hm903210", "hm903249-hm903210", "HM903249-HM903210", "4T-HM903249-HM903210" ], "locale_variants": {} }, { "sku": "527-522", "brand": "NTN", "manufacturer_designation": "NTN 4T-527/522", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 101.6, "B_mm": 34.925, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 150, "static_load_kN": 165, "limiting_speed_rpm": 3800, "max_rpm": 3800, "speed_oil_rpm": 5000, "weight_g": 1360, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-527/522 is the NTN 4T catalogue entry for a 44.45×101.6×34.925 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 527 identifies the cone of 44.45 mm (1.75 in) bore by catalogue lookup, and 522 fixes the 101.6 mm OD. Grease relubrication at the 3,800 r/min limiting speed targets the cone-rib contact; sustaining 5,000 r/min needs an oil supply directed at the large roller ends. Cup-side note for 522: within the pure-numeric inch family tables the 527 cone is listed against several cup options, and it is the cup that fixes the 101.6 mm OD and the 34.925 mm assembled width — quote the full 527/522 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 44.45 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-527/522.", "The pure-numeric inch family at 44.45 mm bore (101.6×34.925 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 527/522 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 44.45 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Inch and metric bores collide on paper — 44.45 mm is 1.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Do not confuse T (34.925 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 150/165 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-527/522; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-527/522?", "a": "4T-527/522 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 101.6 mm outside diameter and 34.925 mm assembled width T (4 × 1.375 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 150 kN, C0 165 kN, grease limiting speed 3,800 r/min, oil speed 5,000 r/min, mass about 1360 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-527/522 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 527 cone or the 522 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 150/165 kN ratings change with the cup." }, { "q": "What is the difference between 4T-527/522 and a metric ISO 355 tapered bearing?", "a": "4T-527/522 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×101.6×34.925 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-527/522 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 527/522 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-527/522 list two speeds, 3,800 and 5,000 r/min?", "a": "The lower figure, 3,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-527/522 at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "527", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-527-522", "527-522", "4T-527-522" ], "locale_variants": {} }, { "sku": "45280-45220", "brand": "NTN", "manufacturer_designation": "NTN 4T-45280/45220", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 104.775, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 144, "static_load_kN": 169, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.75 in (44.45 mm) shaft position as 4T-45280/45220: cone 45280, cup 45220, profiled rollers and a pressed-steel cage, rated 144 kN basic dynamic and 169 kN static. Reading the designation: 4T-45280/45220 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 3.2 kN of dynamic capacity per millimetre of bore summarises the 144 kN rating over the 44.45 mm bore — sanity-check any interchange candidate against this ratio and the 30.162 mm T. The printed 144/169 kN ratings belong to the assembled 45280+45220 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 44.45 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-45280/45220.", "The pure-numeric inch family at 44.45 mm bore (104.775×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 45280/45220 reference at purchase.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Inch and metric bores collide on paper — 44.45 mm is 1.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 144/169 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-45280/45220; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-45280/45220?", "a": "4T-45280/45220 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 104.775 mm outside diameter and 30.162 mm assembled width T (4.125 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 144 kN, C0 169 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1330 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-45280/45220 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 45280 cone or the 45220 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 144/169 kN ratings change with the cup." }, { "q": "What is the difference between 4T-45280/45220 and a metric ISO 355 tapered bearing?", "a": "4T-45280/45220 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×104.775×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-45280/45220 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 45280/45220 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-45280/45220 list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-45280/45220 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "45280", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-45280-45220", "45280-45220", "4T-45280-45220" ], "locale_variants": {} }, { "sku": "460-453X", "brand": "NTN", "manufacturer_designation": "NTN 4T-460/453X", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 104.775, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 127, "static_load_kN": 148, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1290, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.75 in (44.45 mm) shaft position as 4T-460/453X: cone 460, cup 453X, profiled rollers and a pressed-steel cage, rated 127 kN basic dynamic and 148 kN static. Cone and cup of 4T-460/453X are separately stocked parts: a worn 453X cup can be replaced against the existing 460 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. The 2.9 kN of dynamic capacity per millimetre of bore summarises the 127 kN rating over the 44.45 mm bore — sanity-check any interchange candidate against this ratio and the 30.162 mm T. Housing fitment sequence for 4T-460/453X: press the 453X cup square into the 104.775 mm seat first, then bring the 460 cone (on its 44.45 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-460/453X run near 3,500 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-460/453X.", "The pure-numeric inch family at 44.45 mm bore (104.775×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 460/453X reference at purchase.", "An unloaded 4T-460/453X near 3,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Quote the full 460/453X pair at ordering: the 460 cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "ABMA makes the 44.45×104.775 mm envelope interchangeable, not the ratings: NTN prints 127/148 kN for this execution and another make of the same number can differ in roller complement.", "The 127/148 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-460/453X; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-460/453X?", "a": "4T-460/453X is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 104.775 mm outside diameter and 30.162 mm assembled width T (4.125 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 127 kN, C0 148 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1290 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-460/453X interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 460 cone or the 453X cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 127/148 kN ratings change with the cup." }, { "q": "What is the difference between 4T-460/453X and a metric ISO 355 tapered bearing?", "a": "4T-460/453X follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×104.775×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-460/453X mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 460/453X references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-460/453X list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-460/453X at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "460", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=181", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "460-453x", "4t-460-453x", "460-453X", "4T-460-453X" ], "locale_variants": {} }, { "sku": "HM807040-HM807010", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM807040/HM807010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 104.775, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 189, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 1620, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-HM807040/HM807010 at 44.45 mm bore (1.75 in), 104.775 mm cup OD and 36.512 mm assembled T, with a grease limiting speed of 3,600 r/min and an oil ceiling of 4,800 r/min. Reading the designation: 4T-HM807040/HM807010 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the heavy-medium HM family lettering ties the pair to its boundary plan. Grease relubrication at the 3,600 r/min limiting speed targets the cone-rib contact; sustaining 4,800 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-HM807040/HM807010: press the HM807010 cup square into the 104.775 mm seat first, then bring the HM807040 cone (on its 44.45 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-HM807040/HM807010; reverse the fit logic when the cup rotates.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM807040/HM807010.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 44.45 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Open 4T-HM807040/HM807010 sets have no seals: a hub or gearbox needs external sealing or the 3,600 r/min grease figure is meaningless once water reaches the cone rib.", "Shaft and housing fillets must clear the ring chamfers of HM807040 and HM807010; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-HM807040/HM807010 near 3,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 153/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM807040/HM807010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM807040/HM807010?", "a": "4T-HM807040/HM807010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 104.775 mm outside diameter and 36.512 mm assembled width T (4.125 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 189 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1620 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM807040/HM807010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM807040 cone or the HM807010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM807040/HM807010 and a metric ISO 355 tapered bearing?", "a": "4T-HM807040/HM807010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×104.775×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM807040/HM807010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM807040/HM807010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM807040/HM807010 list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM807040/HM807010 at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM807040-010", "equiv_brand": "SKF", "level": "partial", "note": "Same 44.45×104.775×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm807040-hm807010", "hm807040-hm807010", "HM807040-HM807010", "4T-HM807040-HM807010" ], "locale_variants": {} }, { "sku": "55175C-55437", "brand": "NTN", "manufacturer_designation": "NTN 4T-55175C/55437", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 111.125, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 115, "static_load_kN": 136, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-55175C/55437 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 44.45×111.125×30.162 mm (assembled width T), for a shaft of about 44.45 mm (1.75 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 55175C sits in the pure-numeric inch family. The 33.3 mm radial section over the 44.45 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 115/136 kN ratings belong to the assembled 55175C+55437 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-55175C/55437 run near 3,200 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-55175C/55437.", "The pure-numeric inch family at 44.45 mm bore (111.125×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 55175C/55437 reference at purchase.", "Quote the full 55175C/55437 pair at ordering: the 55175C cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of 55175C and 55437; use undercut shoulders so the rings seat on the face, not on a radius.", "Fit selection follows the rotating ring: a rotating cone on a 44.45 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 115/136 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-55175C/55437; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-55175C/55437?", "a": "4T-55175C/55437 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 111.125 mm outside diameter and 30.162 mm assembled width T (4.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 115 kN, C0 136 kN, grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1450 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-55175C/55437 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 55175C cone or the 55437 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 115/136 kN ratings change with the cup." }, { "q": "What is the difference between 4T-55175C/55437 and a metric ISO 355 tapered bearing?", "a": "4T-55175C/55437 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×111.125×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-55175C/55437 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 55175C/55437 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-55175C/55437 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-55175C/55437 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "55175C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-55175c-55437", "55175c-55437", "55175C-55437", "4T-55175C-55437" ], "locale_variants": {} }, { "sku": "55176C-55437", "brand": "NTN", "manufacturer_designation": "NTN 4T-55176C/55437", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.45, "D_mm": 111.125, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 115, "static_load_kN": 136, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1090, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.75 in (44.45 mm) shaft position as 4T-55176C/55437: cone 55176C, cup 55437, profiled rollers and a pressed-steel cage, rated 115 kN basic dynamic and 136 kN static. Reading the designation: 4T-55176C/55437 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Speed planning uses both catalogue columns: grease 3,200 r/min is the mechanical ceiling for 4T-55176C/55437, oil 4,200 r/min with circulating oil — a 1,000 r/min margin at this size. The printed 115/136 kN ratings belong to the assembled 55176C+55437 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 44.45 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-55176C/55437.", "The pure-numeric inch family at 44.45 mm bore (111.125×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 55176C/55437 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Shaft and housing fillets must clear the ring chamfers of 55176C and 55437; use undercut shoulders so the rings seat on the face, not on a radius.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 115/136 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-55176C/55437; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-55176C/55437?", "a": "4T-55176C/55437 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 111.125 mm outside diameter and 30.162 mm assembled width T (4.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 115 kN, C0 136 kN, grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1090 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-55176C/55437 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 55176C cone or the 55437 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 115/136 kN ratings change with the cup." }, { "q": "What is the difference between 4T-55176C/55437 and a metric ISO 355 tapered bearing?", "a": "4T-55176C/55437 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×111.125×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-55176C/55437 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 55176C/55437 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-55176C/55437 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-55176C/55437 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "55176C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-55176c-55437", "55176c-55437", "55176C-55437", "4T-55176C-55437" ], "locale_variants": {} }, { "sku": "25584-25520", "brand": "NTN", "manufacturer_designation": "NTN 4T-25584/25520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.983, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 84.5, "static_load_kN": 98, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 556, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-25584/25520 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 44.983×82.931×23.812 mm (assembled width T), for a shaft of about 44.983 mm (1.771 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 25584 identifies the cone of 44.983 mm (1.771 in) bore by catalogue lookup, and 25520 fixes the 82.931 mm OD. Speed planning uses both catalogue columns: grease 4,500 r/min is the mechanical ceiling for 4T-25584/25520, oil 6,000 r/min with circulating oil — a 1,500 r/min margin at this size. The printed 84.5/98 kN ratings belong to the assembled 25584+25520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 44.983 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 44.983 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25584/25520.", "The pure-numeric inch family at 44.983 mm bore (82.931×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25584/25520 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 25584 and 25520; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full 25584/25520 pair at ordering: the 25584 cone also ships against sibling cups, and a cup from another reference changes the 23.812 mm assembled width and the rating.", "Inch and metric bores collide on paper — 44.983 mm is 1.771 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 84.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25584/25520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25584/25520?", "a": "4T-25584/25520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.983 mm bore (1.771 in), 82.931 mm outside diameter and 23.812 mm assembled width T (3.265 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 84.5 kN, C0 98 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 556 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25584/25520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25584 cone or the 25520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 84.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25584/25520 and a metric ISO 355 tapered bearing?", "a": "4T-25584/25520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.983×82.931×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25584/25520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25584/25520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25584/25520 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25584/25520 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25584", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25584-25520", "25584-25520", "4T-25584-25520" ], "locale_variants": {} }, { "sku": "358-354A", "brand": "NTN", "manufacturer_designation": "NTN 4T-358/354A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.983, "D_mm": 85, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 77.5, "static_load_kN": 79.5, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5800, "weight_g": 505, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 44.983 mm carrying combined radial and thrust load, NTN lists 4T-358/354A, a single-row 4T tapered roller set of 77.5 kN C and 79.5 kN C0 inside the 85 mm OD cup. Reading the designation: 4T-358/354A follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 20.638 mm T of each 4T-358/354A enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 77.5/79.5 kN ratings belong to the assembled 358+354A pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 358 cone and 354A cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 44.983 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-358/354A.", "The pure-numeric inch family at 44.983 mm bore (85×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 358/354A reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 20.638 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-358/354A sets have no seals: a hub or gearbox needs external sealing or the 4,400 r/min grease figure is meaningless once water reaches the cone rib.", "An unloaded 4T-358/354A near 4,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 77.5/79.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-358/354A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-358/354A?", "a": "4T-358/354A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.983 mm bore (1.771 in), 85 mm outside diameter and 20.638 mm assembled width T (3.346 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 79.5 kN, grease limiting speed 4,400 r/min, oil speed 5,800 r/min, mass about 505 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-358/354A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 358 cone or the 354A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 77.5/79.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-358/354A and a metric ISO 355 tapered bearing?", "a": "4T-358/354A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.983×85×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-358/354A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 358/354A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-358/354A list two speeds, 4,400 and 5,800 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-358/354A at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "358", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "358-354a", "4t-358-354a", "358-354A", "4T-358-354A" ], "locale_variants": {} }, { "sku": "3776-3720", "brand": "NTN", "manufacturer_designation": "NTN 4T-3776/3720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.983, "D_mm": 93.264, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 134, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3776/3720 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 44.983×93.264×30.162 mm (assembled width T), for a shaft of about 44.983 mm (1.771 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 3776/3720 without it. Grease relubrication at the 4,000 r/min limiting speed targets the cone-rib contact; sustaining 5,300 r/min needs an oil supply directed at the large roller ends. The printed 113/134 kN ratings belong to the assembled 3776+3720 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 44.983 mm cone with an induction heater (max 120 °C) and press the 93.264 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 44.983 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3776/3720.", "The pure-numeric inch family at 44.983 mm bore (93.264×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3776/3720 reference at purchase.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,300 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of 3776 and 3720; use undercut shoulders so the rings seat on the face, not on a radius.", "Never drive the 93.264 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 113/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3776/3720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3776/3720?", "a": "4T-3776/3720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.983 mm bore (1.771 in), 93.264 mm outside diameter and 30.162 mm assembled width T (3.672 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 134 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 950 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3776/3720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3776 cone or the 3720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3776/3720 and a metric ISO 355 tapered bearing?", "a": "4T-3776/3720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.983×93.264×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3776/3720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3776/3720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3776/3720 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3776/3720 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3776", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3776-3720", "3776-3720", "4T-3776-3720" ], "locale_variants": {} }, { "sku": "6277-6220", "brand": "NTN", "manufacturer_designation": "NTN 4T-6277/6220", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 44.983, "D_mm": 127, "B_mm": 50.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 277, "static_load_kN": 320, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 3590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-6277/6220 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 6277 identifies the cone of 44.983 mm (1.771 in) bore by catalogue lookup, and 6220 fixes the 127 mm OD. Catalogue mass of the 4T-6277/6220 cone-plus-cup set is 3590 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 6220: within the pure-numeric inch family tables the 6277 cone is listed against several cup options, and it is the cup that fixes the 127 mm OD and the 50.8 mm assembled width — quote the full 6277/6220 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-6277/6220; reverse the fit logic when the cup rotates.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 44.983 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-6277/6220.", "The pure-numeric inch family at 44.983 mm bore (127×50.8 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 6277/6220 reference at purchase.", "Do not confuse T (50.8 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Do not confuse T (50.8 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-6277/6220 sets have no seals: a hub or gearbox needs external sealing or the 3,200 r/min grease figure is meaningless once water reaches the cone rib.", "The 277/320 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-6277/6220; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-6277/6220?", "a": "4T-6277/6220 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.983 mm bore (1.771 in), 127 mm outside diameter and 50.8 mm assembled width T (5 × 2 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 277 kN, C0 320 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 3590 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-6277/6220 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 6277 cone or the 6220 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 277/320 kN ratings change with the cup." }, { "q": "What is the difference between 4T-6277/6220 and a metric ISO 355 tapered bearing?", "a": "4T-6277/6220 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.983×127×50.8 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-6277/6220 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 6277/6220 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-6277/6220 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-6277/6220 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "6277", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-6277-6220", "6277-6220", "4T-6277-6220" ], "locale_variants": {} }, { "sku": "367-362A", "brand": "NTN", "manufacturer_designation": "NTN 4T-367/362A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 88.9, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 90.5, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.772 in (45 mm) shaft position as 4T-367/362A: cone 367, cup 362A, profiled rollers and a pressed-steel cage, rated 85 kN basic dynamic and 90.5 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 367 identifies the cone of 45 mm (1.772 in) bore by catalogue lookup, and 362A fixes the 88.9 mm OD. The 22.0 mm radial section over the 45 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-367/362A: press the 362A cup square into the 88.9 mm seat first, then bring the 367 cone (on its 45 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-367/362A is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-367/362A.", "The pure-numeric inch family at 45 mm bore (88.9×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 367/362A reference at purchase.", "Quote the full 367/362A pair at ordering: the 367 cone also ships against sibling cups, and a cup from another reference changes the 20.638 mm assembled width and the rating.", "Open 4T-367/362A sets have no seals: a hub or gearbox needs external sealing or the 4,100 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 45×88.9 mm envelope interchangeable, not the ratings: NTN prints 85/90.5 kN for this execution and another make of the same number can differ in roller complement.", "The 85/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-367/362A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-367/362A?", "a": "4T-367/362A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 45 mm bore (1.772 in), 88.9 mm outside diameter and 20.638 mm assembled width T (3.5 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 90.5 kN, grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 600 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-367/362A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 367 cone or the 362A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-367/362A and a metric ISO 355 tapered bearing?", "a": "4T-367/362A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 45×88.9×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-367/362A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 367/362A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-367/362A list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-367/362A at 5,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "367", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "367-362a", "4t-367-362a", "367-362A", "4T-367-362A" ], "locale_variants": {} }, { "sku": "3586-3525-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-3586/3525", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 45.237, "D_mm": 87.312, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 104, "static_load_kN": 117, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5900, "weight_g": 767, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3586/3525 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 45.237×87.312×30.162 mm (assembled width T), for a shaft of about 45.237 mm (1.781 in). Cone and cup of 4T-3586/3525 are separately stocked parts: a worn 3525 cup can be replaced against the existing 3586 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-3586/3525 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-3586/3525: press the 3525 cup square into the 87.312 mm seat first, then bring the 3586 cone (on its 45.237 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-3586/3525, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 45.237 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3586/3525.", "The pure-numeric inch family at 45.237 mm bore (87.312×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3586/3525 reference at purchase.", "Open 4T-3586/3525 sets have no seals: a hub or gearbox needs external sealing or the 4,400 r/min grease figure is meaningless once water reaches the cone rib.", "An unloaded 4T-3586/3525 near 4,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "ABMA makes the 45.237×87.312 mm envelope interchangeable, not the ratings: NTN prints 104/117 kN for this execution and another make of the same number can differ in roller complement.", "The 104/117 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3586/3525; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3586/3525?", "a": "4T-3586/3525 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 45.237 mm bore (1.781 in), 87.312 mm outside diameter and 30.162 mm assembled width T (3.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 104 kN, C0 117 kN, grease limiting speed 4,400 r/min, oil speed 5,900 r/min, mass about 767 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3586/3525 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3586 cone or the 3525 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 104/117 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3586/3525 and a metric ISO 355 tapered bearing?", "a": "4T-3586/3525 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 45.237×87.312×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3586/3525 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3586/3525 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3586/3525 list two speeds, 4,400 and 5,900 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3586/3525 at 5,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3586-3525", "equiv_brand": "SKF", "level": "partial", "note": "Same 45.237×87.312×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3586-3525", "3586-3525", "4T-3586-3525", "3586-3525-NTN" ], "locale_variants": {} }, { "sku": "LM102949-LM102910", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM102949/LM102910", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 45.242, "D_mm": 73.431, "B_mm": 19.558, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 60, "static_load_kN": 76, "limiting_speed_rpm": 4800, "max_rpm": 4800, "speed_oil_rpm": 6400, "weight_g": 309, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.781 in (45.242 mm) shaft position as 4T-LM102949/LM102910: cone LM102949, cup LM102910, profiled rollers and a pressed-steel cage, rated 60 kN basic dynamic and 76 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: LM102949 identifies the cone of 45.242 mm (1.781 in) bore by catalogue lookup, and LM102910 fixes the 73.431 mm OD. Contact-angle geometry of the light-medium LM family gives 4T-LM102949/LM102910 its radial/axial load split — at 60/76 kN the static rating is about 1.27× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for LM102910: within the light-medium LM family tables the LM102949 cone is listed against several cup options, and it is the cup that fixes the 73.431 mm OD and the 19.558 mm assembled width — quote the full LM102949/LM102910 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 45.242 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 45.242 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM102949/LM102910.", "The light-medium LM family at 45.242 mm bore (73.431×19.558 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM102949/LM102910 reference at purchase.", "Do not confuse T (19.558 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 45.242 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of LM102949 and LM102910; use undercut shoulders so the rings seat on the face, not on a radius.", "The 60/76 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM102949/LM102910; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM102949/LM102910?", "a": "4T-LM102949/LM102910 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 45.242 mm bore (1.781 in), 73.431 mm outside diameter and 19.558 mm assembled width T (2.891 × 0.77 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 60 kN, C0 76 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 309 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM102949/LM102910 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM102949 cone or the LM102910 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 60/76 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM102949/LM102910 and a metric ISO 355 tapered bearing?", "a": "4T-LM102949/LM102910 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 45.242×73.431×19.558 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM102949/LM102910 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM102949/LM102910 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM102949/LM102910 list two speeds, 4,800 and 6,400 r/min?", "a": "The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM102949/LM102910 at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM102949-910", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm102949-lm102910", "lm102949-lm102910", "LM102949-LM102910", "4T-LM102949-LM102910" ], "locale_variants": {} }, { "sku": "LM603049-LM603011", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM603049/LM603011", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 45.242, "D_mm": 77.788, "B_mm": 19.842, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 63.5, "static_load_kN": 73.5, "limiting_speed_rpm": 4600, "max_rpm": 4600, "speed_oil_rpm": 6200, "weight_g": 371, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-LM603049/LM603011 is the NTN 4T catalogue entry for a 45.242×77.788×19.842 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: LM603049 identifies the cone of 45.242 mm (1.781 in) bore by catalogue lookup, and LM603011 fixes the 77.788 mm OD. Contact-angle geometry of the light-medium LM family gives 4T-LM603049/LM603011 its radial/axial load split — at 63.5/73.5 kN the static rating is about 1.16× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-LM603049/LM603011: press the LM603011 cup square into the 77.788 mm seat first, then bring the LM603049 cone (on its 45.242 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-LM603049/LM603011 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 45.242 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM603049/LM603011.", "The light-medium LM family at 45.242 mm bore (77.788×19.842 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM603049/LM603011 reference at purchase.", "ABMA makes the 45.242×77.788 mm envelope interchangeable, not the ratings: NTN prints 63.5/73.5 kN for this execution and another make of the same number can differ in roller complement.", "Shaft and housing fillets must clear the ring chamfers of LM603049 and LM603011; use undercut shoulders so the rings seat on the face, not on a radius.", "Do not confuse T (19.842 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 63.5/73.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM603049/LM603011; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM603049/LM603011?", "a": "4T-LM603049/LM603011 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 45.242 mm bore (1.781 in), 77.788 mm outside diameter and 19.842 mm assembled width T (3.063 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 63.5 kN, C0 73.5 kN, grease limiting speed 4,600 r/min, oil speed 6,200 r/min, mass about 371 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM603049/LM603011 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM603049 cone or the LM603011 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 63.5/73.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM603049/LM603011 and a metric ISO 355 tapered bearing?", "a": "4T-LM603049/LM603011 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 45.242×77.788×19.842 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM603049/LM603011 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM603049/LM603011 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM603049/LM603011 list two speeds, 4,600 and 6,200 r/min?", "a": "The lower figure, 4,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM603049/LM603011 at 6,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM603049-011", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM603049-011AA", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "LM603049-012", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm603049-lm603011", "lm603049-lm603011", "LM603049-LM603011", "4T-LM603049-LM603011" ], "locale_variants": {} }, { "sku": "25590-25519", "brand": "NTN", "manufacturer_designation": "NTN 4T-25590/25519", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 45.618, "D_mm": 82.55, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 84.5, "static_load_kN": 98, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 534, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-25590/25519 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 25590 sits in the pure-numeric inch family. Selection: C 84.5 kN against C0 98 kN gives a C0/C ratio of 1.16 for the 45.618 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 84.5/98 kN ratings belong to the assembled 25590+25519 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-25590/25519 run near 4,500 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 45.618 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25590/25519.", "The pure-numeric inch family at 45.618 mm bore (82.55×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25590/25519 reference at purchase.", "An unloaded 4T-25590/25519 near 4,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 23.812 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 84.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25590/25519; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25590/25519?", "a": "4T-25590/25519 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 45.618 mm bore (1.796 in), 82.55 mm outside diameter and 23.812 mm assembled width T (3.25 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 84.5 kN, C0 98 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 534 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25590/25519 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25590 cone or the 25519 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 84.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25590/25519 and a metric ISO 355 tapered bearing?", "a": "4T-25590/25519 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 45.618×82.55×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25590/25519 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25590/25519 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25590/25519 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25590/25519 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25590-25520", "equiv_brand": "SKF", "level": "partial", "note": "Same 45.618×82.55×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25590-25522", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25523", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25520-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25520): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "25590-25522-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25522): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "25590-25526", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25526): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25590-25519", "25590-25519", "4T-25590-25519" ], "locale_variants": {} }, { "sku": "25590-25520-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-25590/25520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 45.618, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 84.5, "static_load_kN": 98, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 544, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-25590/25520 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 25590 and cup 25520 delivered as a matched, separable pair of 45.618 mm bore and 82.931 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 25590 identifies the cone of 45.618 mm (1.796 in) bore by catalogue lookup, and 25520 fixes the 82.931 mm OD. Grease relubrication at the 4,500 r/min limiting speed targets the cone-rib contact; sustaining 6,000 r/min needs an oil supply directed at the large roller ends. The printed 84.5/98 kN ratings belong to the assembled 25590+25520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-25590/25520 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 45.618 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25590/25520.", "The pure-numeric inch family at 45.618 mm bore (82.931×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25590/25520 reference at purchase.", "Never drive the 82.931 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Quote the full 25590/25520 pair at ordering: the 25590 cone also ships against sibling cups, and a cup from another reference changes the 23.812 mm assembled width and the rating.", "Quote the full 25590/25520 pair at ordering: the 25590 cone also ships against sibling cups, and a cup from another reference changes the 23.812 mm assembled width and the rating.", "The 84.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25590/25520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25590/25520?", "a": "4T-25590/25520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 45.618 mm bore (1.796 in), 82.931 mm outside diameter and 23.812 mm assembled width T (3.265 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 84.5 kN, C0 98 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 544 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25590/25520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25590 cone or the 25520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 84.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25590/25520 and a metric ISO 355 tapered bearing?", "a": "4T-25590/25520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 45.618×82.931×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25590/25520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25590/25520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25590/25520 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25590/25520 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25590-25520", "equiv_brand": "SKF", "level": "partial", "note": "Same 45.618×82.931×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25590-25522", "equiv_brand": "SKF", "level": "partial", "note": "Same 45.618×82.931×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25590-25523", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25519", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25519): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "25590-25522-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25522): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "25590-25526", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25526): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25590-25520", "25590-25520", "4T-25590-25520", "25590-25520-NTN" ], "locale_variants": {} }, { "sku": "25590-25522-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-25590/25522", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 45.618, "D_mm": 83.058, "B_mm": 23.876, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 84.5, "static_load_kN": 98, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 545, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-25590/25522 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 25590 and cup 25522 delivered as a matched, separable pair of 45.618 mm bore and 83.058 mm outside diameter. Cone and cup of 4T-25590/25522 are separately stocked parts: a worn 25522 cup can be replaced against the existing 25590 cone, provided the new cup carries the identical reference — pairing across references changes the 23.876 mm assembled width and the rating. The 18.7 mm radial section over the 45.618 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 84.5/98 kN ratings belong to the assembled 25590+25522 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-25590/25522, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 45.618 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25590/25522.", "The pure-numeric inch family at 45.618 mm bore (83.058×23.876 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25590/25522 reference at purchase.", "Inch and metric bores collide on paper — 45.618 mm is 1.796 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "ABMA makes the 45.618×83.058 mm envelope interchangeable, not the ratings: NTN prints 84.5/98 kN for this execution and another make of the same number can differ in roller complement.", "Fit selection follows the rotating ring: a rotating cone on a 45.618 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 84.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25590/25522; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25590/25522?", "a": "4T-25590/25522 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 45.618 mm bore (1.796 in), 83.058 mm outside diameter and 23.876 mm assembled width T (3.27 × 0.94 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 84.5 kN, C0 98 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 545 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25590/25522 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25590 cone or the 25522 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 84.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25590/25522 and a metric ISO 355 tapered bearing?", "a": "4T-25590/25522 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 45.618×83.058×23.876 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25590/25522 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25590/25522 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25590/25522 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25590/25522 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25590-25520", "equiv_brand": "SKF", "level": "partial", "note": "Same 45.618×83.058×23.876 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25590-25522", "equiv_brand": "SKF", "level": "partial", "note": "Same 45.618×83.058×23.876 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "25590-25523", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25519", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25519): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "25590-25520-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25520): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "25590-25526", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25526): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25590-25522", "25590-25522", "4T-25590-25522", "25590-25522-NTN" ], "locale_variants": {} }, { "sku": "25590-25526", "brand": "NTN", "manufacturer_designation": "NTN 4T-25590/25526", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 45.618, "D_mm": 85, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 84.5, "static_load_kN": 98, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 581, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-25590/25526 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-25590/25526 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Contact-angle geometry of the pure-numeric inch family gives 4T-25590/25526 its radial/axial load split — at 84.5/98 kN the static rating is about 1.16× C, typical of inch tapered sets proportioned for combined duty. The printed 84.5/98 kN ratings belong to the assembled 25590+25526 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-25590/25526 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 45.618 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25590/25526.", "The pure-numeric inch family at 45.618 mm bore (85×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25590/25526 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 25590 and 25526; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full 25590/25526 pair at ordering: the 25590 cone also ships against sibling cups, and a cup from another reference changes the 23.812 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 45.618 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 84.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25590/25526; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25590/25526?", "a": "4T-25590/25526 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 45.618 mm bore (1.796 in), 85 mm outside diameter and 23.812 mm assembled width T (3.346 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 84.5 kN, C0 98 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 581 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25590/25526 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25590 cone or the 25526 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 84.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25590/25526 and a metric ISO 355 tapered bearing?", "a": "4T-25590/25526 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 45.618×85×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25590/25526 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25590/25526 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25590/25526 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25590/25526 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25590-25520", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25522", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25523", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "25590-25519", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25519): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "25590-25520-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25520): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "25590-25522-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-25590 paired with a different cup (25522): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25590-25526", "25590-25526", "4T-25590-25526" ], "locale_variants": {} }, { "sku": "LM503349A-LM503310", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM503349A/LM503310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 45.987, "D_mm": 74.976, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 56.5, "static_load_kN": 71, "limiting_speed_rpm": 4700, "max_rpm": 4700, "speed_oil_rpm": 6300, "weight_g": 298, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-LM503349A/LM503310 is the NTN 4T catalogue entry for a 45.987×74.976×18 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Reading the designation: 4T-LM503349A/LM503310 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the light-medium LM family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 45.987×74.976×18 mm converts to 1.811 × 2.952 × 0.709 in; the ABMA envelope swaps with like-numbered inch parts but the 56.5/71 kN ratings are NTN-specific. The printed 56.5/71 kN ratings belong to the assembled LM503349A+LM503310 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-LM503349A/LM503310 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 45.987 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM503349A/LM503310.", "The light-medium LM family at 45.987 mm bore (74.976×18 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM503349A/LM503310 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 45.987 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (18 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Grease packs must leave free volume inside the 18 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,300 r/min raises temperature and destroys the setting.", "The 56.5/71 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM503349A/LM503310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM503349A/LM503310?", "a": "4T-LM503349A/LM503310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 45.987 mm bore (1.811 in), 74.976 mm outside diameter and 18 mm assembled width T (2.952 × 0.709 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 56.5 kN, C0 71 kN, grease limiting speed 4,700 r/min, oil speed 6,300 r/min, mass about 298 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM503349A/LM503310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM503349A cone or the LM503310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 56.5/71 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM503349A/LM503310 and a metric ISO 355 tapered bearing?", "a": "4T-LM503349A/LM503310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 45.987×74.976×18 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM503349A/LM503310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM503349A/LM503310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM503349A/LM503310 list two speeds, 4,700 and 6,300 r/min?", "a": "The lower figure, 4,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM503349A/LM503310 at 6,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM503349A-310", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm503349a-lm503310", "lm503349a-lm503310", "LM503349A-LM503310", "4T-LM503349A-LM503310" ], "locale_variants": {} }, { "sku": "18690-18620-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-18690/18620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 46.038, "D_mm": 79.375, "B_mm": 17.462, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 50.5, "static_load_kN": 56, "limiting_speed_rpm": 4600, "max_rpm": 4600, "speed_oil_rpm": 6200, "weight_g": 331, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-18690/18620 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 18690 and cup 18620 delivered as a matched, separable pair of 46.038 mm bore and 79.375 mm outside diameter. Cone and cup of 4T-18690/18620 are separately stocked parts: a worn 18620 cup can be replaced against the existing 18690 cone, provided the new cup carries the identical reference — pairing across references changes the 17.462 mm assembled width and the rating. Catalogue mass of the 4T-18690/18620 cone-plus-cup set is 331 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 18620: within the pure-numeric inch family tables the 18690 cone is listed against several cup options, and it is the cup that fixes the 79.375 mm OD and the 17.462 mm assembled width — quote the full 18690/18620 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-18690/18620 run near 4,600 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 46.038 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-18690/18620.", "The pure-numeric inch family at 46.038 mm bore (79.375×17.462 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 18690/18620 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 46.038 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Replacing one half of an adjusted pair without resetting end play negates the 17.462 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 46.038 mm is 1.813 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 50.5/56 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-18690/18620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-18690/18620?", "a": "4T-18690/18620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 46.038 mm bore (1.813 in), 79.375 mm outside diameter and 17.462 mm assembled width T (3.125 × 0.687 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 50.5 kN, C0 56 kN, grease limiting speed 4,600 r/min, oil speed 6,200 r/min, mass about 331 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-18690/18620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 18690 cone or the 18620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 50.5/56 kN ratings change with the cup." }, { "q": "What is the difference between 4T-18690/18620 and a metric ISO 355 tapered bearing?", "a": "4T-18690/18620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 46.038×79.375×17.462 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-18690/18620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 18690/18620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-18690/18620 list two speeds, 4,600 and 6,200 r/min?", "a": "The lower figure, 4,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-18690/18620 at 6,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "18690-18620", "equiv_brand": "SKF", "level": "partial", "note": "Same 46.038×79.375×17.462 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-18690-18620", "18690-18620", "4T-18690-18620", "18690-18620-NTN" ], "locale_variants": {} }, { "sku": "25592-25520", "brand": "NTN", "manufacturer_designation": "NTN 4T-25592/25520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 46.038, "D_mm": 82.931, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 84.5, "static_load_kN": 98, "limiting_speed_rpm": 4500, "max_rpm": 4500, "speed_oil_rpm": 6000, "weight_g": 538, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-25592/25520 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 46.038×82.931×23.812 mm (assembled width T), for a shaft of about 46.038 mm (1.813 in). Cone and cup of 4T-25592/25520 are separately stocked parts: a worn 25520 cup can be replaced against the existing 25592 cone, provided the new cup carries the identical reference — pairing across references changes the 23.812 mm assembled width and the rating. Grease relubrication at the 4,500 r/min limiting speed targets the cone-rib contact; sustaining 6,000 r/min needs an oil supply directed at the large roller ends. Cup-side note for 25520: within the pure-numeric inch family tables the 25592 cone is listed against several cup options, and it is the cup that fixes the 82.931 mm OD and the 23.812 mm assembled width — quote the full 25592/25520 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-25592/25520, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 46.038 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-25592/25520.", "The pure-numeric inch family at 46.038 mm bore (82.931×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 25592/25520 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 25592 and 25520; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 23.812 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,000 r/min raises temperature and destroys the setting.", "Grease packs must leave free volume inside the 23.812 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,000 r/min raises temperature and destroys the setting.", "The 84.5/98 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-25592/25520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-25592/25520?", "a": "4T-25592/25520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 46.038 mm bore (1.813 in), 82.931 mm outside diameter and 23.812 mm assembled width T (3.265 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 84.5 kN, C0 98 kN, grease limiting speed 4,500 r/min, oil speed 6,000 r/min, mass about 538 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-25592/25520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 25592 cone or the 25520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 84.5/98 kN ratings change with the cup." }, { "q": "What is the difference between 4T-25592/25520 and a metric ISO 355 tapered bearing?", "a": "4T-25592/25520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 46.038×82.931×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-25592/25520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 25592/25520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-25592/25520 list two speeds, 4,500 and 6,000 r/min?", "a": "The lower figure, 4,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-25592/25520 at 6,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "25592", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-25592-25520", "25592-25520", "4T-25592-25520" ], "locale_variants": {} }, { "sku": "2984-2924", "brand": "NTN", "manufacturer_designation": "NTN 4T-2984/2924", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 46.038, "D_mm": 85, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 87.5, "static_load_kN": 104, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5800, "weight_g": 616, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-2984/2924 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 2984 and cup 2924 delivered as a matched, separable pair of 46.038 mm bore and 85 mm outside diameter. Cone and cup of 4T-2984/2924 are separately stocked parts: a worn 2924 cup can be replaced against the existing 2984 cone, provided the new cup carries the identical reference — pairing across references changes the 25.4 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 4,400 r/min is the mechanical ceiling for 4T-2984/2924, oil 5,800 r/min with circulating oil — a 1,400 r/min margin at this size. Cup-side note for 2924: within the pure-numeric inch family tables the 2984 cone is listed against several cup options, and it is the cup that fixes the 85 mm OD and the 25.4 mm assembled width — quote the full 2984/2924 pair, never the cone alone. Fillet radii must clear the chamfers of the 2984 cone and 2924 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 46.038 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-2984/2924.", "The pure-numeric inch family at 46.038 mm bore (85×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 2984/2924 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 2984 and 2924; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 25.4 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,800 r/min raises temperature and destroys the setting.", "Quote the full 2984/2924 pair at ordering: the 2984 cone also ships against sibling cups, and a cup from another reference changes the 25.4 mm assembled width and the rating.", "The 87.5/104 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-2984/2924; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-2984/2924?", "a": "4T-2984/2924 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 46.038 mm bore (1.813 in), 85 mm outside diameter and 25.4 mm assembled width T (3.346 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 87.5 kN, C0 104 kN, grease limiting speed 4,400 r/min, oil speed 5,800 r/min, mass about 616 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-2984/2924 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 2984 cone or the 2924 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 87.5/104 kN ratings change with the cup." }, { "q": "What is the difference between 4T-2984/2924 and a metric ISO 355 tapered bearing?", "a": "4T-2984/2924 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 46.038×85×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-2984/2924 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 2984/2924 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-2984/2924 list two speeds, 4,400 and 5,800 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-2984/2924 at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "2984", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-2984-2924", "2984-2924", "4T-2984-2924" ], "locale_variants": {} }, { "sku": "359A-354A", "brand": "NTN", "manufacturer_designation": "NTN 4T-359A/354A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 46.038, "D_mm": 85, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 77.5, "static_load_kN": 79.5, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5800, "weight_g": 489, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.813 in (46.038 mm) shaft position as 4T-359A/354A: cone 359A, cup 354A, profiled rollers and a pressed-steel cage, rated 77.5 kN basic dynamic and 79.5 kN static. Reading the designation: 4T-359A/354A follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 19.5 mm radial section over the 46.038 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 354A: within the pure-numeric inch family tables the 359A cone is listed against several cup options, and it is the cup that fixes the 85 mm OD and the 20.638 mm assembled width — quote the full 359A/354A pair, never the cone alone. Fillet radii must clear the chamfers of the 359A cone and 354A cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 46.038 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-359A/354A.", "The pure-numeric inch family at 46.038 mm bore (85×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 359A/354A reference at purchase.", "An unloaded 4T-359A/354A near 4,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of 359A and 354A; use undercut shoulders so the rings seat on the face, not on a radius.", "Open 4T-359A/354A sets have no seals: a hub or gearbox needs external sealing or the 4,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 77.5/79.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-359A/354A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-359A/354A?", "a": "4T-359A/354A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 46.038 mm bore (1.813 in), 85 mm outside diameter and 20.638 mm assembled width T (3.346 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 79.5 kN, grease limiting speed 4,400 r/min, oil speed 5,800 r/min, mass about 489 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-359A/354A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 359A cone or the 354A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 77.5/79.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-359A/354A and a metric ISO 355 tapered bearing?", "a": "4T-359A/354A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 46.038×85×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-359A/354A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 359A/354A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-359A/354A list two speeds, 4,400 and 5,800 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-359A/354A at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "359A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "359a-354a", "4t-359a-354a", "359A-354A", "4T-359A-354A" ], "locale_variants": {} }, { "sku": "359S-352", "brand": "NTN", "manufacturer_designation": "NTN 4T-359S/352", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 46.038, "D_mm": 90.119, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 77.5, "static_load_kN": 79.5, "limiting_speed_rpm": 4400, "max_rpm": 4400, "speed_oil_rpm": 5800, "weight_g": 654, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-359S/352 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 46.038×90.119×23 mm (assembled width T), for a shaft of about 46.038 mm (1.813 in). Reading the designation: 4T-359S/352 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 23 mm T of each 4T-359S/352 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 352: within the pure-numeric inch family tables the 359S cone is listed against several cup options, and it is the cup that fixes the 90.119 mm OD and the 23 mm assembled width — quote the full 359S/352 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-359S/352 run near 4,400 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 46.038 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-359S/352.", "The pure-numeric inch family at 46.038 mm bore (90.119×23 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 359S/352 reference at purchase.", "Grease packs must leave free volume inside the 23 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,800 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 46.038 mm is 1.813 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 23 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,800 r/min raises temperature and destroys the setting.", "The 77.5/79.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-359S/352; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-359S/352?", "a": "4T-359S/352 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 46.038 mm bore (1.813 in), 90.119 mm outside diameter and 23 mm assembled width T (3.548 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 79.5 kN, grease limiting speed 4,400 r/min, oil speed 5,800 r/min, mass about 654 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-359S/352 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 359S cone or the 352 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 77.5/79.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-359S/352 and a metric ISO 355 tapered bearing?", "a": "4T-359S/352 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 46.038×90.119×23 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-359S/352 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 359S/352 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-359S/352 list two speeds, 4,400 and 5,800 r/min?", "a": "The lower figure, 4,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-359S/352 at 5,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "359S-354X", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "359s-352", "4t-359s-352", "359S-352", "4T-359S-352" ], "locale_variants": {} }, { "sku": "3777-3720", "brand": "NTN", "manufacturer_designation": "NTN 4T-3777/3720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 46.038, "D_mm": 93.264, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 134, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 934, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3777/3720 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 46.038×93.264×30.162 mm (assembled width T), for a shaft of about 46.038 mm (1.813 in). Reading the designation: 4T-3777/3720 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 2.5 kN of dynamic capacity per millimetre of bore summarises the 113 kN rating over the 46.038 mm bore — sanity-check any interchange candidate against this ratio and the 30.162 mm T. The printed 113/134 kN ratings belong to the assembled 3777+3720 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-3777/3720 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 46.038 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3777/3720.", "The pure-numeric inch family at 46.038 mm bore (93.264×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3777/3720 reference at purchase.", "Open 4T-3777/3720 sets have no seals: a hub or gearbox needs external sealing or the 4,000 r/min grease figure is meaningless once water reaches the cone rib.", "Never drive the 93.264 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 46.038×93.264 mm envelope interchangeable, not the ratings: NTN prints 113/134 kN for this execution and another make of the same number can differ in roller complement.", "The 113/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3777/3720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3777/3720?", "a": "4T-3777/3720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 46.038 mm bore (1.813 in), 93.264 mm outside diameter and 30.162 mm assembled width T (3.672 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 134 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 934 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3777/3720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3777 cone or the 3720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3777/3720 and a metric ISO 355 tapered bearing?", "a": "4T-3777/3720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 46.038×93.264×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3777/3720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3777/3720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3777/3720 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3777/3720 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3777", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3777-3720", "3777-3720", "4T-3777-3720" ], "locale_variants": {} }, { "sku": "436-432", "brand": "NTN", "manufacturer_designation": "NTN 4T-436/432", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 46.038, "D_mm": 95.25, "B_mm": 27.783, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 120, "static_load_kN": 129, "limiting_speed_rpm": 4200, "max_rpm": 4200, "speed_oil_rpm": 5600, "weight_g": 930, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-436/432 at 46.038 mm bore (1.813 in), 95.25 mm cup OD and 27.783 mm assembled T, with a grease limiting speed of 4,200 r/min and an oil ceiling of 5,600 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 436 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 4,200 r/min is the mechanical ceiling for 4T-436/432, oil 5,600 r/min with circulating oil — a 1,400 r/min margin at this size. Cup-side note for 432: within the pure-numeric inch family tables the 436 cone is listed against several cup options, and it is the cup that fixes the 95.25 mm OD and the 27.783 mm assembled width — quote the full 436/432 pair, never the cone alone. Running clearance of 4T-436/432 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 46.038 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-436/432.", "The pure-numeric inch family at 46.038 mm bore (95.25×27.783 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 436/432 reference at purchase.", "Open 4T-436/432 sets have no seals: a hub or gearbox needs external sealing or the 4,200 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 46.038×95.25 mm envelope interchangeable, not the ratings: NTN prints 120/129 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 436/432 pair at ordering: the 436 cone also ships against sibling cups, and a cup from another reference changes the 27.783 mm assembled width and the rating.", "The 120/129 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-436/432; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-436/432?", "a": "4T-436/432 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 46.038 mm bore (1.813 in), 95.25 mm outside diameter and 27.783 mm assembled width T (3.75 × 1.094 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 120 kN, C0 129 kN, grease limiting speed 4,200 r/min, oil speed 5,600 r/min, mass about 930 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-436/432 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 436 cone or the 432 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 120/129 kN ratings change with the cup." }, { "q": "What is the difference between 4T-436/432 and a metric ISO 355 tapered bearing?", "a": "4T-436/432 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 46.038×95.25×27.783 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-436/432 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 436/432 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-436/432 list two speeds, 4,200 and 5,600 r/min?", "a": "The lower figure, 4,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-436/432 at 5,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "436", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-436-432", "436-432", "4T-436-432" ], "locale_variants": {} }, { "sku": "369A-362A", "brand": "NTN", "manufacturer_designation": "NTN 4T-369A/362A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 47.625, "D_mm": 88.9, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 90.5, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 564, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-369A/362A is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 47.625×88.9×20.638 mm (assembled width T), for a shaft of about 47.625 mm (1.875 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 369A/362A without it. Catalogue mass of the 4T-369A/362A cone-plus-cup set is 564 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 362A: within the pure-numeric inch family tables the 369A cone is listed against several cup options, and it is the cup that fixes the 88.9 mm OD and the 20.638 mm assembled width — quote the full 369A/362A pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-369A/362A is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 47.625 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-369A/362A.", "The pure-numeric inch family at 47.625 mm bore (88.9×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 369A/362A reference at purchase.", "An unloaded 4T-369A/362A near 4,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 47.625 mm is 1.875 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-369A/362A sets have no seals: a hub or gearbox needs external sealing or the 4,100 r/min grease figure is meaningless once water reaches the cone rib.", "The 85/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-369A/362A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-369A/362A?", "a": "4T-369A/362A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 47.625 mm bore (1.875 in), 88.9 mm outside diameter and 20.638 mm assembled width T (3.5 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 90.5 kN, grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 564 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-369A/362A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 369A cone or the 362A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-369A/362A and a metric ISO 355 tapered bearing?", "a": "4T-369A/362A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 47.625×88.9×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-369A/362A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 369A/362A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-369A/362A list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-369A/362A at 5,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "369A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "369a-362a", "4t-369a-362a", "369A-362A", "4T-369A-362A" ], "locale_variants": {} }, { "sku": "M804048-M804010", "brand": "NTN", "manufacturer_designation": "NTN 4T-M804048/M804010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 47.625, "D_mm": 88.9, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 91, "static_load_kN": 101, "limiting_speed_rpm": 4200, "max_rpm": 4200, "speed_oil_rpm": 5600, "weight_g": 664, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-M804048/M804010 is the NTN 4T catalogue entry for a 47.625×88.9×25.4 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-M804048/M804010 are separately stocked parts: a worn M804010 cup can be replaced against the existing M804048 cone, provided the new cup carries the identical reference — pairing across references changes the 25.4 mm assembled width and the rating. Contact-angle geometry of the medium M family gives 4T-M804048/M804010 its radial/axial load split — at 91/101 kN the static rating is about 1.11× C, typical of inch tapered sets proportioned for combined duty. The printed 91/101 kN ratings belong to the assembled M804048+M804010 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-M804048/M804010 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 47.625 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-M804048/M804010.", "The medium M family at 47.625 mm bore (88.9×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full M804048/M804010 reference at purchase.", "Quote the full M804048/M804010 pair at ordering: the M804048 cone also ships against sibling cups, and a cup from another reference changes the 25.4 mm assembled width and the rating.", "Grease packs must leave free volume inside the 25.4 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,600 r/min raises temperature and destroys the setting.", "Never drive the 88.9 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 91/101 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-M804048/M804010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-M804048/M804010?", "a": "4T-M804048/M804010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 47.625 mm bore (1.875 in), 88.9 mm outside diameter and 25.4 mm assembled width T (3.5 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 91 kN, C0 101 kN, grease limiting speed 4,200 r/min, oil speed 5,600 r/min, mass about 664 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-M804048/M804010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the M804048 cone or the M804010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 91/101 kN ratings change with the cup." }, { "q": "What is the difference between 4T-M804048/M804010 and a metric ISO 355 tapered bearing?", "a": "4T-M804048/M804010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 47.625×88.9×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-M804048/M804010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare M804048/M804010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-M804048/M804010 list two speeds, 4,200 and 5,600 r/min?", "a": "The lower figure, 4,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-M804048/M804010 at 5,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "M804048", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-m804048-m804010", "m804048-m804010", "M804048-M804010", "4T-M804048-M804010" ], "locale_variants": {} }, { "sku": "3778-3720", "brand": "NTN", "manufacturer_designation": "NTN 4T-3778/3720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 47.625, "D_mm": 93.264, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 134, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 896, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 47.625 mm carrying combined radial and thrust load, NTN lists 4T-3778/3720, a single-row 4T tapered roller set of 113 kN C and 134 kN C0 inside the 93.264 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 3778/3720 without it. Catalogue mass of the 4T-3778/3720 cone-plus-cup set is 896 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 113/134 kN ratings belong to the assembled 3778+3720 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-3778/3720 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 47.625 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3778/3720.", "The pure-numeric inch family at 47.625 mm bore (93.264×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3778/3720 reference at purchase.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "An unloaded 4T-3778/3720 near 4,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Fit selection follows the rotating ring: a rotating cone on a 47.625 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 113/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3778/3720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3778/3720?", "a": "4T-3778/3720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 47.625 mm bore (1.875 in), 93.264 mm outside diameter and 30.162 mm assembled width T (3.672 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 134 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 896 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3778/3720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3778 cone or the 3720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3778/3720 and a metric ISO 355 tapered bearing?", "a": "4T-3778/3720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 47.625×93.264×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3778/3720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3778/3720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3778/3720 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3778/3720 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3778", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3778-3720", "3778-3720", "4T-3778-3720" ], "locale_variants": {} }, { "sku": "HM804846-HM804810", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM804846/HM804810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 47.625, "D_mm": 95.25, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 120, "static_load_kN": 147, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 979, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM804846/HM804810 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote HM804846/HM804810 without it. Speed planning uses both catalogue columns: grease 4,000 r/min is the mechanical ceiling for 4T-HM804846/HM804810, oil 5,300 r/min with circulating oil — a 1,300 r/min margin at this size. Housing fitment sequence for 4T-HM804846/HM804810: press the HM804810 cup square into the 95.25 mm seat first, then bring the HM804846 cone (on its 47.625 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-HM804846/HM804810; reverse the fit logic when the cup rotates.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 47.625 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM804846/HM804810.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 47.625 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,300 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 47.625 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 47.625 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 120/147 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM804846/HM804810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM804846/HM804810?", "a": "4T-HM804846/HM804810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 47.625 mm bore (1.875 in), 95.25 mm outside diameter and 30.162 mm assembled width T (3.75 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 120 kN, C0 147 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 979 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM804846/HM804810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM804846 cone or the HM804810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 120/147 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM804846/HM804810 and a metric ISO 355 tapered bearing?", "a": "4T-HM804846/HM804810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 47.625×95.25×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM804846/HM804810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM804846/HM804810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM804846/HM804810 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM804846/HM804810 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM804846-810", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm804846-hm804810", "hm804846-hm804810", "HM804846-HM804810", "4T-HM804846-HM804810" ], "locale_variants": {} }, { "sku": "386A-382A", "brand": "NTN", "manufacturer_designation": "NTN 4T-386A/382A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 47.625, "D_mm": 96.838, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 96.5, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 719, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-386A/382A is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 47.625×96.838×21 mm (assembled width T), for a shaft of about 47.625 mm (1.875 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 386A/382A without it. Selection: C 86.5 kN against C0 96.5 kN gives a C0/C ratio of 1.12 for the 47.625 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 382A: within the pure-numeric inch family tables the 386A cone is listed against several cup options, and it is the cup that fixes the 96.838 mm OD and the 21 mm assembled width — quote the full 386A/382A pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-386A/382A pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 47.625 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-386A/382A.", "The pure-numeric inch family at 47.625 mm bore (96.838×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 386A/382A reference at purchase.", "Quote the full 386A/382A pair at ordering: the 386A cone also ships against sibling cups, and a cup from another reference changes the 21 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 47.625 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 386A/382A pair at ordering: the 386A cone also ships against sibling cups, and a cup from another reference changes the 21 mm assembled width and the rating.", "The 86.5/96.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-386A/382A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-386A/382A?", "a": "4T-386A/382A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 47.625 mm bore (1.875 in), 96.838 mm outside diameter and 21 mm assembled width T (3.813 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 96.5 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 719 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-386A/382A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 386A cone or the 382A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/96.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-386A/382A and a metric ISO 355 tapered bearing?", "a": "4T-386A/382A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 47.625×96.838×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-386A/382A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 386A/382A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-386A/382A list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-386A/382A at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "386A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "386a-382a", "4t-386a-382a", "386A-382A", "4T-386A-382A" ], "locale_variants": {} }, { "sku": "528-522", "brand": "NTN", "manufacturer_designation": "NTN 4T-528/522", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 47.625, "D_mm": 101.6, "B_mm": 34.925, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 150, "static_load_kN": 165, "limiting_speed_rpm": 3800, "max_rpm": 3800, "speed_oil_rpm": 5000, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-528/522 at 47.625 mm bore (1.875 in), 101.6 mm cup OD and 34.925 mm assembled T, with a grease limiting speed of 3,800 r/min and an oil ceiling of 5,000 r/min. Reading the designation: 4T-528/522 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 27.0 mm radial section over the 47.625 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 522: within the pure-numeric inch family tables the 528 cone is listed against several cup options, and it is the cup that fixes the 101.6 mm OD and the 34.925 mm assembled width — quote the full 528/522 pair, never the cone alone. Fillet radii must clear the chamfers of the 528 cone and 522 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 47.625 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-528/522.", "The pure-numeric inch family at 47.625 mm bore (101.6×34.925 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 528/522 reference at purchase.", "Do not confuse T (34.925 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 47.625 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Replacing one half of an adjusted pair without resetting end play negates the 34.925 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 150/165 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-528/522; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-528/522?", "a": "4T-528/522 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 47.625 mm bore (1.875 in), 101.6 mm outside diameter and 34.925 mm assembled width T (4 × 1.375 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 150 kN, C0 165 kN, grease limiting speed 3,800 r/min, oil speed 5,000 r/min, mass about 1300 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-528/522 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 528 cone or the 522 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 150/165 kN ratings change with the cup." }, { "q": "What is the difference between 4T-528/522 and a metric ISO 355 tapered bearing?", "a": "4T-528/522 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 47.625×101.6×34.925 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-528/522 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 528/522 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-528/522 list two speeds, 3,800 and 5,000 r/min?", "a": "The lower figure, 3,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-528/522 at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "528", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-528-522", "528-522", "4T-528-522" ], "locale_variants": {} }, { "sku": "45282-45220", "brand": "NTN", "manufacturer_designation": "NTN 4T-45282/45220", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 47.625, "D_mm": 104.775, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 144, "static_load_kN": 169, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-45282/45220 at 47.625 mm bore (1.875 in), 104.775 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 3,500 r/min and an oil ceiling of 4,700 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 45282 identifies the cone of 47.625 mm (1.875 in) bore by catalogue lookup, and 45220 fixes the 104.775 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-45282/45220 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-45282/45220: press the 45220 cup square into the 104.775 mm seat first, then bring the 45282 cone (on its 47.625 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-45282/45220 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 47.625 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-45282/45220.", "The pure-numeric inch family at 47.625 mm bore (104.775×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 45282/45220 reference at purchase.", "ABMA makes the 47.625×104.775 mm envelope interchangeable, not the ratings: NTN prints 144/169 kN for this execution and another make of the same number can differ in roller complement.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 144/169 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-45282/45220; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-45282/45220?", "a": "4T-45282/45220 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 47.625 mm bore (1.875 in), 104.775 mm outside diameter and 30.162 mm assembled width T (4.125 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 144 kN, C0 169 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1330 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-45282/45220 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 45282 cone or the 45220 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 144/169 kN ratings change with the cup." }, { "q": "What is the difference between 4T-45282/45220 and a metric ISO 355 tapered bearing?", "a": "4T-45282/45220 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 47.625×104.775×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-45282/45220 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 45282/45220 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-45282/45220 list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-45282/45220 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "45282", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-45282-45220", "45282-45220", "4T-45282-45220" ], "locale_variants": {} }, { "sku": "463-453X", "brand": "NTN", "manufacturer_designation": "NTN 4T-463/453X", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 47.625, "D_mm": 104.775, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 127, "static_load_kN": 148, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-463/453X is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 47.625×104.775×30.162 mm (assembled width T), for a shaft of about 47.625 mm (1.875 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 463 sits in the pure-numeric inch family. The 28.6 mm radial section over the 47.625 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 127/148 kN ratings belong to the assembled 463+453X pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-463/453X; reverse the fit logic when the cup rotates.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 47.625 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-463/453X.", "The pure-numeric inch family at 47.625 mm bore (104.775×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 463/453X reference at purchase.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-463/453X sets have no seals: a hub or gearbox needs external sealing or the 3,500 r/min grease figure is meaningless once water reaches the cone rib.", "Quote the full 463/453X pair at ordering: the 463 cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "The 127/148 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-463/453X; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-463/453X?", "a": "4T-463/453X is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 47.625 mm bore (1.875 in), 104.775 mm outside diameter and 30.162 mm assembled width T (4.125 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 127 kN, C0 148 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1240 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-463/453X interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 463 cone or the 453X cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 127/148 kN ratings change with the cup." }, { "q": "What is the difference between 4T-463/453X and a metric ISO 355 tapered bearing?", "a": "4T-463/453X follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 47.625×104.775×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-463/453X mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 463/453X references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-463/453X list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-463/453X at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "463", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=182", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "463-453x", "4t-463-453x", "463-453X", "4T-463-453X" ], "locale_variants": {} }, { "sku": "55187C-55437", "brand": "NTN", "manufacturer_designation": "NTN 4T-55187C/55437", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 47.625, "D_mm": 111.125, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 115, "static_load_kN": 136, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-55187C/55437 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 55187C identifies the cone of 47.625 mm (1.875 in) bore by catalogue lookup, and 55437 fixes the 111.125 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-55187C/55437 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 115/136 kN ratings belong to the assembled 55187C+55437 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 47.625 mm cone with an induction heater (max 120 °C) and press the 111.125 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 47.625 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-55187C/55437.", "The pure-numeric inch family at 47.625 mm bore (111.125×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 55187C/55437 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Shaft and housing fillets must clear the ring chamfers of 55187C and 55437; use undercut shoulders so the rings seat on the face, not on a radius.", "Never drive the 111.125 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 115/136 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-55187C/55437; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-55187C/55437?", "a": "4T-55187C/55437 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 47.625 mm bore (1.875 in), 111.125 mm outside diameter and 30.162 mm assembled width T (4.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 115 kN, C0 136 kN, grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1400 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-55187C/55437 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 55187C cone or the 55437 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 115/136 kN ratings change with the cup." }, { "q": "What is the difference between 4T-55187C/55437 and a metric ISO 355 tapered bearing?", "a": "4T-55187C/55437 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 47.625×111.125×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-55187C/55437 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 55187C/55437 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-55187C/55437 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-55187C/55437 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "55187C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-55187c-55437", "55187c-55437", "55187C-55437", "4T-55187C-55437" ], "locale_variants": {} }, { "sku": "72188C-72487", "brand": "NTN", "manufacturer_designation": "NTN 4T-72188C/72487", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 47.625, "D_mm": 123.825, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 171, "static_load_kN": 188, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3900, "weight_g": 2160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-72188C/72487 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-72188C/72487 are separately stocked parts: a worn 72487 cup can be replaced against the existing 72188C cone, provided the new cup carries the identical reference — pairing across references changes the 36.512 mm assembled width and the rating. Selection: C 171 kN against C0 188 kN gives a C0/C ratio of 1.10 for the 47.625 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 72487: within the pure-numeric inch family tables the 72188C cone is listed against several cup options, and it is the cup that fixes the 123.825 mm OD and the 36.512 mm assembled width — quote the full 72188C/72487 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-72188C/72487 run near 2,900 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 47.625 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-72188C/72487.", "The pure-numeric inch family at 47.625 mm bore (123.825×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 72188C/72487 reference at purchase.", "Open 4T-72188C/72487 sets have no seals: a hub or gearbox needs external sealing or the 2,900 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 47.625×123.825 mm envelope interchangeable, not the ratings: NTN prints 171/188 kN for this execution and another make of the same number can differ in roller complement.", "Shaft and housing fillets must clear the ring chamfers of 72188C and 72487; use undercut shoulders so the rings seat on the face, not on a radius.", "The 171/188 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-72188C/72487; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-72188C/72487?", "a": "4T-72188C/72487 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 47.625 mm bore (1.875 in), 123.825 mm outside diameter and 36.512 mm assembled width T (4.875 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 171 kN, C0 188 kN, grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 2160 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-72188C/72487 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 72188C cone or the 72487 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 171/188 kN ratings change with the cup." }, { "q": "What is the difference between 4T-72188C/72487 and a metric ISO 355 tapered bearing?", "a": "4T-72188C/72487 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 47.625×123.825×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-72188C/72487 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 72188C/72487 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-72188C/72487 list two speeds, 2,900 and 3,900 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-72188C/72487 at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "72188C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-72188c-72487", "72188c-72487", "72188C-72487", "4T-72188C-72487" ], "locale_variants": {} }, { "sku": "HM804848-HM804810", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM804848/HM804810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 48.412, "D_mm": 95.25, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 120, "static_load_kN": 147, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 967, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-HM804848/HM804810 at 48.412 mm bore (1.906 in), 95.25 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 4,000 r/min and an oil ceiling of 5,300 r/min. Cone and cup of 4T-HM804848/HM804810 are separately stocked parts: a worn HM804810 cup can be replaced against the existing HM804848 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Grease relubrication at the 4,000 r/min limiting speed targets the cone-rib contact; sustaining 5,300 r/min needs an oil supply directed at the large roller ends. The printed 120/147 kN ratings belong to the assembled HM804848+HM804810 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-HM804848/HM804810 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 48.412 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM804848/HM804810.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 48.412 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Fit selection follows the rotating ring: a rotating cone on a 48.412 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "An unloaded 4T-HM804848/HM804810 near 4,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 120/147 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM804848/HM804810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM804848/HM804810?", "a": "4T-HM804848/HM804810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 48.412 mm bore (1.906 in), 95.25 mm outside diameter and 30.162 mm assembled width T (3.75 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 120 kN, C0 147 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 967 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM804848/HM804810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM804848 cone or the HM804810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 120/147 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM804848/HM804810 and a metric ISO 355 tapered bearing?", "a": "4T-HM804848/HM804810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 48.412×95.25×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM804848/HM804810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM804848/HM804810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM804848/HM804810 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM804848/HM804810 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM804848", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm804848-hm804810", "hm804848-hm804810", "HM804848-HM804810", "4T-HM804848-HM804810" ], "locale_variants": {} }, { "sku": "HM804849-HM804810", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM804849/HM804810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 48.412, "D_mm": 95.25, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 120, "static_load_kN": 147, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 965, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM804849/HM804810 is the NTN 4T catalogue entry for a 48.412×95.25×30.162 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HM804849 sits in the heavy-medium HM family. Selection: C 120 kN against C0 147 kN gives a C0/C ratio of 1.23 for the 48.412 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 120/147 kN ratings belong to the assembled HM804849+HM804810 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-HM804849/HM804810; reverse the fit logic when the cup rotates.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 48.412 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM804849/HM804810.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 48.412 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Quote the full HM804849/HM804810 pair at ordering: the HM804849 cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "ABMA makes the 48.412×95.25 mm envelope interchangeable, not the ratings: NTN prints 120/147 kN for this execution and another make of the same number can differ in roller complement.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 120/147 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM804849/HM804810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM804849/HM804810?", "a": "4T-HM804849/HM804810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 48.412 mm bore (1.906 in), 95.25 mm outside diameter and 30.162 mm assembled width T (3.75 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 120 kN, C0 147 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 965 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM804849/HM804810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM804849 cone or the HM804810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 120/147 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM804849/HM804810 and a metric ISO 355 tapered bearing?", "a": "4T-HM804849/HM804810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 48.412×95.25×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM804849/HM804810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM804849/HM804810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM804849/HM804810 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM804849/HM804810 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM804849", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm804849-hm804810", "hm804849-hm804810", "HM804849-HM804810", "4T-HM804849-HM804810" ], "locale_variants": {} }, { "sku": "3781-3720", "brand": "NTN", "manufacturer_designation": "NTN 4T-3781/3720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 49.212, "D_mm": 93.264, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 134, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 876, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3781/3720 is the NTN 4T catalogue entry for a 49.212×93.264×30.162 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 3781/3720 without it. Speed planning uses both catalogue columns: grease 4,000 r/min is the mechanical ceiling for 4T-3781/3720, oil 5,300 r/min with circulating oil — a 1,300 r/min margin at this size. The printed 113/134 kN ratings belong to the assembled 3781+3720 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 3781 cone and 3720 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 49.212 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3781/3720.", "The pure-numeric inch family at 49.212 mm bore (93.264×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3781/3720 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 49.212 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of 3781 and 3720; use undercut shoulders so the rings seat on the face, not on a radius.", "Open 4T-3781/3720 sets have no seals: a hub or gearbox needs external sealing or the 4,000 r/min grease figure is meaningless once water reaches the cone rib.", "The 113/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3781/3720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3781/3720?", "a": "4T-3781/3720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 49.212 mm bore (1.937 in), 93.264 mm outside diameter and 30.162 mm assembled width T (3.672 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 134 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 876 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3781/3720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3781 cone or the 3720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3781/3720 and a metric ISO 355 tapered bearing?", "a": "4T-3781/3720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 49.212×93.264×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3781/3720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3781/3720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3781/3720 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3781/3720 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3781", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3781-3720", "3781-3720", "4T-3781-3720" ], "locale_variants": {} }, { "sku": "5395-5335", "brand": "NTN", "manufacturer_designation": "NTN 4T-5395/5335", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 49.212, "D_mm": 103.188, "B_mm": 43.658, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 193, "static_load_kN": 232, "limiting_speed_rpm": 3800, "max_rpm": 3800, "speed_oil_rpm": 5000, "weight_g": 1750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-5395/5335 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-5395/5335 are separately stocked parts: a worn 5335 cup can be replaced against the existing 5395 cone, provided the new cup carries the identical reference — pairing across references changes the 43.658 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 43.658 mm T of each 4T-5395/5335 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 5335: within the pure-numeric inch family tables the 5395 cone is listed against several cup options, and it is the cup that fixes the 103.188 mm OD and the 43.658 mm assembled width — quote the full 5395/5335 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-5395/5335 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 49.212 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-5395/5335.", "The pure-numeric inch family at 49.212 mm bore (103.188×43.658 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 5395/5335 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 49.212 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (43.658 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Do not confuse T (43.658 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 193/232 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-5395/5335; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-5395/5335?", "a": "4T-5395/5335 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 49.212 mm bore (1.937 in), 103.188 mm outside diameter and 43.658 mm assembled width T (4.063 × 1.719 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 193 kN, C0 232 kN, grease limiting speed 3,800 r/min, oil speed 5,000 r/min, mass about 1750 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-5395/5335 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 5395 cone or the 5335 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 193/232 kN ratings change with the cup." }, { "q": "What is the difference between 4T-5395/5335 and a metric ISO 355 tapered bearing?", "a": "4T-5395/5335 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 49.212×103.188×43.658 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-5395/5335 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 5395/5335 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-5395/5335 list two speeds, 3,800 and 5,000 r/min?", "a": "The lower figure, 3,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-5395/5335 at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "5395", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-5395-5335", "5395-5335", "4T-5395-5335" ], "locale_variants": {} }, { "sku": "HM807044-HM807010", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM807044/HM807010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 49.212, "D_mm": 104.775, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 189, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 1520, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 49.212 mm carrying combined radial and thrust load, NTN lists 4T-HM807044/HM807010, a single-row 4T tapered roller set of 153 kN C and 189 kN C0 inside the 104.775 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HM807044 sits in the heavy-medium HM family. Speed planning uses both catalogue columns: grease 3,600 r/min is the mechanical ceiling for 4T-HM807044/HM807010, oil 4,800 r/min with circulating oil — a 1,200 r/min margin at this size. The printed 153/189 kN ratings belong to the assembled HM807044+HM807010 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-HM807044/HM807010 run near 3,600 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 49.212 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM807044/HM807010.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 49.212 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "An unloaded 4T-HM807044/HM807010 near 3,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 49.212 mm is 1.937 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 36.512 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,800 r/min raises temperature and destroys the setting.", "The 153/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM807044/HM807010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM807044/HM807010?", "a": "4T-HM807044/HM807010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 49.212 mm bore (1.937 in), 104.775 mm outside diameter and 36.512 mm assembled width T (4.125 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 189 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1520 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM807044/HM807010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM807044 cone or the HM807010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM807044/HM807010 and a metric ISO 355 tapered bearing?", "a": "4T-HM807044/HM807010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 49.212×104.775×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM807044/HM807010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM807044/HM807010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM807044/HM807010 list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM807044/HM807010 at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM807044", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm807044-hm807010", "hm807044-hm807010", "HM807044-HM807010", "4T-HM807044-HM807010" ], "locale_variants": {} }, { "sku": "65390-65320-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-65390/65320", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 49.212, "D_mm": 114.3, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 206, "static_load_kN": 225, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 2230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.937 in (49.212 mm) shaft position as 4T-65390/65320: cone 65390, cup 65320, profiled rollers and a pressed-steel cage, rated 206 kN basic dynamic and 225 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 65390/65320 without it. Grease relubrication at the 3,600 r/min limiting speed targets the cone-rib contact; sustaining 4,800 r/min needs an oil supply directed at the large roller ends. The printed 206/225 kN ratings belong to the assembled 65390+65320 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-65390/65320, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 49.212 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-65390/65320.", "The pure-numeric inch family at 49.212 mm bore (114.3×44.45 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 65390/65320 reference at purchase.", "Quote the full 65390/65320 pair at ordering: the 65390 cone also ships against sibling cups, and a cup from another reference changes the 44.45 mm assembled width and the rating.", "Replacing one half of an adjusted pair without resetting end play negates the 44.45 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never drive the 114.3 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 206/225 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-65390/65320; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-65390/65320?", "a": "4T-65390/65320 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 49.212 mm bore (1.937 in), 114.3 mm outside diameter and 44.45 mm assembled width T (4.5 × 1.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 206 kN, C0 225 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 2230 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-65390/65320 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 65390 cone or the 65320 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 206/225 kN ratings change with the cup." }, { "q": "What is the difference between 4T-65390/65320 and a metric ISO 355 tapered bearing?", "a": "4T-65390/65320 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 49.212×114.3×44.45 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-65390/65320 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 65390/65320 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-65390/65320 list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-65390/65320 at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "65390-65320", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-65390-65320", "65390-65320", "4T-65390-65320", "65390-65320-NTN" ], "locale_variants": {} }, { "sku": "HH506348-HH506310", "brand": "NTN", "manufacturer_designation": "NTN 4T-HH506348/HH506310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 49.212, "D_mm": 114.3, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 226, "static_load_kN": 261, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 2330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.937 in (49.212 mm) shaft position as 4T-HH506348/HH506310: cone HH506348, cup HH506310, profiled rollers and a pressed-steel cage, rated 226 kN basic dynamic and 261 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote HH506348/HH506310 without it. Speed planning uses both catalogue columns: grease 3,500 r/min is the mechanical ceiling for 4T-HH506348/HH506310, oil 4,700 r/min with circulating oil — a 1,200 r/min margin at this size. Cup-side note for HH506310: within the extra-heavy HH family tables the HH506348 cone is listed against several cup options, and it is the cup that fixes the 114.3 mm OD and the 44.45 mm assembled width — quote the full HH506348/HH506310 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-HH506348/HH506310, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 49.212 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HH506348/HH506310.", "The extra-heavy HH family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 49.212 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "An unloaded 4T-HH506348/HH506310 near 3,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of HH506348 and HH506310; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full HH506348/HH506310 pair at ordering: the HH506348 cone also ships against sibling cups, and a cup from another reference changes the 44.45 mm assembled width and the rating.", "The 226/261 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HH506348/HH506310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HH506348/HH506310?", "a": "4T-HH506348/HH506310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 49.212 mm bore (1.937 in), 114.3 mm outside diameter and 44.45 mm assembled width T (4.5 × 1.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 226 kN, C0 261 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 2330 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HH506348/HH506310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HH506348 cone or the HH506310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 226/261 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HH506348/HH506310 and a metric ISO 355 tapered bearing?", "a": "4T-HH506348/HH506310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 49.212×114.3×44.45 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HH506348/HH506310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HH506348/HH506310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HH506348/HH506310 list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HH506348/HH506310 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HH506348", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hh506348-hh506310", "hh506348-hh506310", "HH506348-HH506310", "4T-HH506348-HH506310" ], "locale_variants": {} }, { "sku": "LM104947A-LM104911", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM104947A/LM104911", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 49.987, "D_mm": 82.55, "B_mm": 21.59, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 77.5, "static_load_kN": 94, "limiting_speed_rpm": 4300, "max_rpm": 4300, "speed_oil_rpm": 5700, "weight_g": 434, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-LM104947A/LM104911 at 49.987 mm bore (1.968 in), 82.55 mm cup OD and 21.59 mm assembled T, with a grease limiting speed of 4,300 r/min and an oil ceiling of 5,700 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote LM104947A/LM104911 without it. Imperial cross-check for the drawing: 49.987×82.55×21.59 mm converts to 1.968 × 3.25 × 0.85 in; the ABMA envelope swaps with like-numbered inch parts but the 77.5/94 kN ratings are NTN-specific. The printed 77.5/94 kN ratings belong to the assembled LM104947A+LM104911 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 49.987 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 49.987 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM104947A/LM104911.", "The light-medium LM family at 49.987 mm bore (82.55×21.59 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM104947A/LM104911 reference at purchase.", "An unloaded 4T-LM104947A/LM104911 near 4,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Fit selection follows the rotating ring: a rotating cone on a 49.987 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Inch and metric bores collide on paper — 49.987 mm is 1.968 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 77.5/94 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM104947A/LM104911; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM104947A/LM104911?", "a": "4T-LM104947A/LM104911 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 49.987 mm bore (1.968 in), 82.55 mm outside diameter and 21.59 mm assembled width T (3.25 × 0.85 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 94 kN, grease limiting speed 4,300 r/min, oil speed 5,700 r/min, mass about 434 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM104947A/LM104911 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM104947A cone or the LM104911 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 77.5/94 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM104947A/LM104911 and a metric ISO 355 tapered bearing?", "a": "4T-LM104947A/LM104911 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 49.987×82.55×21.59 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM104947A/LM104911 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM104947A/LM104911 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM104947A/LM104911 list two speeds, 4,300 and 5,700 r/min?", "a": "The lower figure, 4,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM104947A/LM104911 at 5,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM104947A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm104947a-lm104911", "lm104947a-lm104911", "LM104947A-LM104911", "4T-LM104947A-LM104911" ], "locale_variants": {} }, { "sku": "28579-28521", "brand": "NTN", "manufacturer_designation": "NTN 4T-28579/28521", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 49.987, "D_mm": 92.075, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 93, "static_load_kN": 116, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 718, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-28579/28521 is the NTN 4T catalogue entry for a 49.987×92.075×24.608 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 28579 identifies the cone of 49.987 mm (1.968 in) bore by catalogue lookup, and 28521 fixes the 92.075 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 24.608 mm T of each 4T-28579/28521 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-28579/28521: press the 28521 cup square into the 92.075 mm seat first, then bring the 28579 cone (on its 49.987 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-28579/28521 run near 4,000 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 49.987 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-28579/28521.", "The pure-numeric inch family at 49.987 mm bore (92.075×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28579/28521 reference at purchase.", "Never drive the 92.075 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Replacing one half of an adjusted pair without resetting end play negates the 24.608 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 49.987 mm is 1.968 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 93/116 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28579/28521; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28579/28521?", "a": "4T-28579/28521 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 49.987 mm bore (1.968 in), 92.075 mm outside diameter and 24.608 mm assembled width T (3.625 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 93 kN, C0 116 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 718 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28579/28521 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28579 cone or the 28521 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 93/116 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28579/28521 and a metric ISO 355 tapered bearing?", "a": "4T-28579/28521 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 49.987×92.075×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28579/28521 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28579/28521 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28579/28521 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28579/28521 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28579", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28579-28521", "28579-28521", "4T-28579-28521" ], "locale_variants": {} }, { "sku": "HH506349-HH506310", "brand": "NTN", "manufacturer_designation": "NTN 4T-HH506349/HH506310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 49.987, "D_mm": 114.3, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 226, "static_load_kN": 261, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 2310, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-HH506349/HH506310 denotes the extra-heavy HH family of NTN inch tapered roller bearings — cone HH506349 and cup HH506310 delivered as a matched, separable pair of 49.987 mm bore and 114.3 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HH506349 identifies the cone of 49.987 mm (1.968 in) bore by catalogue lookup, and HH506310 fixes the 114.3 mm OD. Contact-angle geometry of the extra-heavy HH family gives 4T-HH506349/HH506310 its radial/axial load split — at 226/261 kN the static rating is about 1.15× C, typical of inch tapered sets proportioned for combined duty. The printed 226/261 kN ratings belong to the assembled HH506349+HH506310 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-HH506349/HH506310 run near 3,500 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 49.987 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HH506349/HH506310.", "The extra-heavy HH family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 49.987 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Grease packs must leave free volume inside the 44.45 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,700 r/min raises temperature and destroys the setting.", "An unloaded 4T-HH506349/HH506310 near 3,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (44.45 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 226/261 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HH506349/HH506310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HH506349/HH506310?", "a": "4T-HH506349/HH506310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 49.987 mm bore (1.968 in), 114.3 mm outside diameter and 44.45 mm assembled width T (4.5 × 1.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 226 kN, C0 261 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 2310 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HH506349/HH506310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HH506349 cone or the HH506310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 226/261 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HH506349/HH506310 and a metric ISO 355 tapered bearing?", "a": "4T-HH506349/HH506310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 49.987×114.3×44.45 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HH506349/HH506310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HH506349/HH506310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HH506349/HH506310 list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HH506349/HH506310 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HH506349", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hh506349-hh506310", "hh506349-hh506310", "HH506349-HH506310", "4T-HH506349-HH506310" ], "locale_variants": {} }, { "sku": "JLM104948-JLM104910", "brand": "NTN", "manufacturer_designation": "NTN 4T-JLM104948/JLM104910", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 82, "B_mm": 21.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 77.5, "static_load_kN": 94, "limiting_speed_rpm": 4300, "max_rpm": 4300, "speed_oil_rpm": 5700, "weight_g": 420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-JLM104948/JLM104910 denotes the JLM prefixed family of NTN inch tapered roller bearings — cone JLM104948 and cup JLM104910 delivered as a matched, separable pair of 50 mm bore and 82 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — JLM104948 sits in the JLM prefixed family. Grease relubrication at the 4,300 r/min limiting speed targets the cone-rib contact; sustaining 5,700 r/min needs an oil supply directed at the large roller ends. The printed 77.5/94 kN ratings belong to the assembled JLM104948+JLM104910 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-JLM104948/JLM104910 run near 4,300 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 50 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-JLM104948/JLM104910.", "The J-prefixed JLM104948 code belongs to a metric-envelope inch family: its 50 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Open 4T-JLM104948/JLM104910 sets have no seals: a hub or gearbox needs external sealing or the 4,300 r/min grease figure is meaningless once water reaches the cone rib.", "Open 4T-JLM104948/JLM104910 sets have no seals: a hub or gearbox needs external sealing or the 4,300 r/min grease figure is meaningless once water reaches the cone rib.", "Open 4T-JLM104948/JLM104910 sets have no seals: a hub or gearbox needs external sealing or the 4,300 r/min grease figure is meaningless once water reaches the cone rib.", "The 77.5/94 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JLM104948/JLM104910; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JLM104948/JLM104910?", "a": "4T-JLM104948/JLM104910 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50 mm bore (1.969 in), 82 mm outside diameter and 21.5 mm assembled width T (3.228 × 0.846 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 94 kN, grease limiting speed 4,300 r/min, oil speed 5,700 r/min, mass about 420 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JLM104948/JLM104910 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JLM104948 cone or the JLM104910 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 77.5/94 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JLM104948/JLM104910 and a metric ISO 355 tapered bearing?", "a": "4T-JLM104948/JLM104910 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50×82×21.5 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JLM104948/JLM104910 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JLM104948/JLM104910 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JLM104948/JLM104910 list two speeds, 4,300 and 5,700 r/min?", "a": "The lower figure, 4,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JLM104948/JLM104910 at 5,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JLM104948", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jlm104948-jlm104910", "4t-jlm104948-jlm104910", "jlm104948-jlm104910", "JLM104948-JLM104910", "4T-JLM104948-JLM104910" ], "locale_variants": {} }, { "sku": "JLM704649-JLM704610", "brand": "NTN", "manufacturer_designation": "NTN 4T-JLM704649/JLM704610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 84, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 77.5, "static_load_kN": 94.5, "limiting_speed_rpm": 4300, "max_rpm": 4300, "speed_oil_rpm": 5700, "weight_g": 466, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JLM704649/JLM704610 belongs to the NTN inch 4T tapered roller range (JLM prefixed family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-JLM704649/JLM704610 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the JLM prefixed family lettering ties the pair to its boundary plan. Grease relubrication at the 4,300 r/min limiting speed targets the cone-rib contact; sustaining 5,700 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-JLM704649/JLM704610: press the JLM704610 cup square into the 84 mm seat first, then bring the JLM704649 cone (on its 50 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-JLM704649/JLM704610 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 50 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-JLM704649/JLM704610.", "The J-prefixed JLM704649 code belongs to a metric-envelope inch family: its 50 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Shaft and housing fillets must clear the ring chamfers of JLM704649 and JLM704610; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of JLM704649 and JLM704610; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 22 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,700 r/min raises temperature and destroys the setting.", "The 77.5/94.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JLM704649/JLM704610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JLM704649/JLM704610?", "a": "4T-JLM704649/JLM704610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50 mm bore (1.969 in), 84 mm outside diameter and 22 mm assembled width T (3.307 × 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 94.5 kN, grease limiting speed 4,300 r/min, oil speed 5,700 r/min, mass about 466 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JLM704649/JLM704610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JLM704649 cone or the JLM704610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 77.5/94.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JLM704649/JLM704610 and a metric ISO 355 tapered bearing?", "a": "4T-JLM704649/JLM704610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50×84×22 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JLM704649/JLM704610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JLM704649/JLM704610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JLM704649/JLM704610 list two speeds, 4,300 and 5,700 r/min?", "a": "The lower figure, 4,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JLM704649/JLM704610 at 5,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JLM704649", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jlm704649-jlm704610", "4t-jlm704649-jlm704610", "jlm704649-jlm704610", "JLM704649-JLM704610", "4T-JLM704649-JLM704610" ], "locale_variants": {} }, { "sku": "365-362A", "brand": "NTN", "manufacturer_designation": "NTN 4T-365/362A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 88.9, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 90.5, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 534, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-365/362A at 50 mm bore (1.969 in), 88.9 mm cup OD and 20.638 mm assembled T, with a grease limiting speed of 4,100 r/min and an oil ceiling of 5,500 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 365 identifies the cone of 50 mm (1.969 in) bore by catalogue lookup, and 362A fixes the 88.9 mm OD. Catalogue mass of the 4T-365/362A cone-plus-cup set is 534 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-365/362A: press the 362A cup square into the 88.9 mm seat first, then bring the 365 cone (on its 50 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Contact-pattern check with marking blue: a pattern biased to one roller end means the 50 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 50 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-365/362A.", "The pure-numeric inch family at 50 mm bore (88.9×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 365/362A reference at purchase.", "Do not confuse T (20.638 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "ABMA makes the 50×88.9 mm envelope interchangeable, not the ratings: NTN prints 85/90.5 kN for this execution and another make of the same number can differ in roller complement.", "Grease packs must leave free volume inside the 20.638 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,500 r/min raises temperature and destroys the setting.", "The 85/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-365/362A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-365/362A?", "a": "4T-365/362A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50 mm bore (1.969 in), 88.9 mm outside diameter and 20.638 mm assembled width T (3.5 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 90.5 kN, grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 534 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-365/362A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 365 cone or the 362A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-365/362A and a metric ISO 355 tapered bearing?", "a": "4T-365/362A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50×88.9×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-365/362A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 365/362A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-365/362A list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-365/362A at 5,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "365", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "365-362a", "4t-365-362a", "365-362A", "4T-365-362A" ], "locale_variants": {} }, { "sku": "366-362A", "brand": "NTN", "manufacturer_designation": "NTN 4T-366/362A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 88.9, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 90.5, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 1.969 in (50 mm) shaft position as 4T-366/362A: cone 366, cup 362A, profiled rollers and a pressed-steel cage, rated 85 kN basic dynamic and 90.5 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 366/362A without it. Catalogue mass of the 4T-366/362A cone-plus-cup set is 530 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-366/362A: press the 362A cup square into the 88.9 mm seat first, then bring the 366 cone (on its 50 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-366/362A run near 4,100 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 50 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-366/362A.", "The pure-numeric inch family at 50 mm bore (88.9×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 366/362A reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 50 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 50 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Never drive the 88.9 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 85/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-366/362A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-366/362A?", "a": "4T-366/362A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50 mm bore (1.969 in), 88.9 mm outside diameter and 20.638 mm assembled width T (3.5 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 90.5 kN, grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 530 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-366/362A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 366 cone or the 362A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-366/362A and a metric ISO 355 tapered bearing?", "a": "4T-366/362A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50×88.9×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-366/362A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 366/362A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-366/362A list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-366/362A at 5,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "366", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "366-362a", "4t-366-362a", "366-362A", "4T-366-362A" ], "locale_variants": {} }, { "sku": "JM205149-JM205110", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM205149/JM205110", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 90, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 118, "static_load_kN": 141, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5400, "weight_g": 755, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 50 mm carrying combined radial and thrust load, NTN lists 4T-JM205149/JM205110, a single-row 4T tapered roller set of 118 kN C and 141 kN C0 inside the 90 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: JM205149 identifies the cone of 50 mm (1.969 in) bore by catalogue lookup, and JM205110 fixes the 90 mm OD. The 2.4 kN of dynamic capacity per millimetre of bore summarises the 118 kN rating over the 50 mm bore — sanity-check any interchange candidate against this ratio and the 28 mm T. Housing fitment sequence for 4T-JM205149/JM205110: press the JM205110 cup square into the 90 mm seat first, then bring the JM205149 cone (on its 50 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-JM205149/JM205110 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 50 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-JM205149/JM205110.", "The J-prefixed JM205149 code belongs to a metric-envelope inch family: its 50 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Inch and metric bores collide on paper — 50 mm is 1.969 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 28 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,400 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of JM205149 and JM205110; use undercut shoulders so the rings seat on the face, not on a radius.", "The 118/141 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM205149/JM205110; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM205149/JM205110?", "a": "4T-JM205149/JM205110 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50 mm bore (1.969 in), 90 mm outside diameter and 28 mm assembled width T (3.543 × 1.102 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 118 kN, C0 141 kN, grease limiting speed 4,100 r/min, oil speed 5,400 r/min, mass about 755 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM205149/JM205110 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM205149 cone or the JM205110 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 118/141 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM205149/JM205110 and a metric ISO 355 tapered bearing?", "a": "4T-JM205149/JM205110 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50×90×28 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM205149/JM205110 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM205149/JM205110 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM205149/JM205110 list two speeds, 4,100 and 5,400 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM205149/JM205110 at 5,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM205149", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm205149-jm205110", "4t-jm205149-jm205110", "jm205149-jm205110", "JM205149-JM205110", "4T-JM205149-JM205110" ], "locale_variants": {} }, { "sku": "JHM807045-JHM807012", "brand": "NTN", "manufacturer_designation": "NTN 4T-JHM807045/JHM807012", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 105, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 189, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 1520, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-JHM807045/JHM807012 at 50 mm bore (1.969 in), 105 mm cup OD and 37 mm assembled T, with a grease limiting speed of 3,600 r/min and an oil ceiling of 4,800 r/min. Reading the designation: 4T-JHM807045/JHM807012 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the JHM heavy metric-envelope family lettering ties the pair to its boundary plan. The 27.5 mm radial section over the 50 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for JHM807012: within the JHM heavy metric-envelope family tables the JHM807045 cone is listed against several cup options, and it is the cup that fixes the 105 mm OD and the 37 mm assembled width — quote the full JHM807045/JHM807012 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-JHM807045/JHM807012 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 50 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-JHM807045/JHM807012.", "The J-prefixed JHM807045 code belongs to a metric-envelope inch family: its 50 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Fit selection follows the rotating ring: a rotating cone on a 50 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full JHM807045/JHM807012 pair at ordering: the JHM807045 cone also ships against sibling cups, and a cup from another reference changes the 37 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 50 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 153/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JHM807045/JHM807012; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JHM807045/JHM807012?", "a": "4T-JHM807045/JHM807012 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50 mm bore (1.969 in), 105 mm outside diameter and 37 mm assembled width T (4.134 × 1.457 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 189 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1520 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JHM807045/JHM807012 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JHM807045 cone or the JHM807012 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JHM807045/JHM807012 and a metric ISO 355 tapered bearing?", "a": "4T-JHM807045/JHM807012 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50×105×37 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JHM807045/JHM807012 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JHM807045/JHM807012 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JHM807045/JHM807012 list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JHM807045/JHM807012 at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JHM807045", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jhm807045-jhm807012", "4t-jhm807045-jhm807012", "jhm807045-jhm807012", "JHM807045-JHM807012", "4T-JHM807045-JHM807012" ], "locale_variants": {} }, { "sku": "396-394A", "brand": "NTN", "manufacturer_designation": "NTN 4T-396/394A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 110, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 99.5, "static_load_kN": 120, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 1070, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-396/394A is the NTN 4T catalogue entry for a 50×110×22 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Reading the designation: 4T-396/394A follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Speed planning uses both catalogue columns: grease 3,200 r/min is the mechanical ceiling for 4T-396/394A, oil 4,300 r/min with circulating oil — a 1,100 r/min margin at this size. Cup-side note for 394A: within the pure-numeric inch family tables the 396 cone is listed against several cup options, and it is the cup that fixes the 110 mm OD and the 22 mm assembled width — quote the full 396/394A pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 50 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 50 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-396/394A.", "The pure-numeric inch family at 50 mm bore (110×22 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 396/394A reference at purchase.", "Open 4T-396/394A sets have no seals: a hub or gearbox needs external sealing or the 3,200 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 50×110 mm envelope interchangeable, not the ratings: NTN prints 99.5/120 kN for this execution and another make of the same number can differ in roller complement.", "Grease packs must leave free volume inside the 22 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,300 r/min raises temperature and destroys the setting.", "The 99.5/120 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-396/394A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-396/394A?", "a": "4T-396/394A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50 mm bore (1.969 in), 110 mm outside diameter and 22 mm assembled width T (4.331 × 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 99.5 kN, C0 120 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 1070 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-396/394A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 396 cone or the 394A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 99.5/120 kN ratings change with the cup." }, { "q": "What is the difference between 4T-396/394A and a metric ISO 355 tapered bearing?", "a": "4T-396/394A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50×110×22 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-396/394A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 396/394A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-396/394A list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-396/394A at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "396", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "396-394a", "4t-396-394a", "396-394A", "4T-396-394A" ], "locale_variants": {} }, { "sku": "LM104949-LM104911", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM104949/LM104911", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 82.55, "B_mm": 21.59, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 77.5, "static_load_kN": 94, "limiting_speed_rpm": 4300, "max_rpm": 4300, "speed_oil_rpm": 5700, "weight_g": 418, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2 in (50.8 mm) shaft position as 4T-LM104949/LM104911: cone LM104949, cup LM104911, profiled rollers and a pressed-steel cage, rated 77.5 kN basic dynamic and 94 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote LM104949/LM104911 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 21.59 mm T of each 4T-LM104949/LM104911 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 77.5/94 kN ratings belong to the assembled LM104949+LM104911 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 50.8 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM104949/LM104911.", "The light-medium LM family at 50.8 mm bore (82.55×21.59 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM104949/LM104911 reference at purchase.", "Do not confuse T (21.59 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 50.8 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of LM104949 and LM104911; use undercut shoulders so the rings seat on the face, not on a radius.", "The 77.5/94 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM104949/LM104911; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM104949/LM104911?", "a": "4T-LM104949/LM104911 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 82.55 mm outside diameter and 21.59 mm assembled width T (3.25 × 0.85 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 94 kN, grease limiting speed 4,300 r/min, oil speed 5,700 r/min, mass about 418 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM104949/LM104911 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM104949 cone or the LM104911 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 77.5/94 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM104949/LM104911 and a metric ISO 355 tapered bearing?", "a": "4T-LM104949/LM104911 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×82.55×21.59 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM104949/LM104911 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM104949/LM104911 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM104949/LM104911 list two speeds, 4,300 and 5,700 r/min?", "a": "The lower figure, 4,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM104949/LM104911 at 5,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM104949-911", "equiv_brand": "SKF", "level": "partial", "note": "Same 50.8×82.55×21.59 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm104949-lm104911", "lm104949-lm104911", "LM104949-LM104911", "4T-LM104949-LM104911" ], "locale_variants": {} }, { "sku": "18790-18720-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-18790/18720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 85, "B_mm": 17.462, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 55, "static_load_kN": 65, "limiting_speed_rpm": 4200, "max_rpm": 4200, "speed_oil_rpm": 5600, "weight_g": 375, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-18790/18720 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 18790 identifies the cone of 50.8 mm (2 in) bore by catalogue lookup, and 18720 fixes the 85 mm OD. Grease relubrication at the 4,200 r/min limiting speed targets the cone-rib contact; sustaining 5,600 r/min needs an oil supply directed at the large roller ends. Cup-side note for 18720: within the pure-numeric inch family tables the 18790 cone is listed against several cup options, and it is the cup that fixes the 85 mm OD and the 17.462 mm assembled width — quote the full 18790/18720 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 50.8 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-18790/18720.", "The pure-numeric inch family at 50.8 mm bore (85×17.462 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 18790/18720 reference at purchase.", "Open 4T-18790/18720 sets have no seals: a hub or gearbox needs external sealing or the 4,200 r/min grease figure is meaningless once water reaches the cone rib.", "Shaft and housing fillets must clear the ring chamfers of 18790 and 18720; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of 18790 and 18720; use undercut shoulders so the rings seat on the face, not on a radius.", "The 55/65 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-18790/18720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-18790/18720?", "a": "4T-18790/18720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 85 mm outside diameter and 17.462 mm assembled width T (3.346 × 0.687 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 55 kN, C0 65 kN, grease limiting speed 4,200 r/min, oil speed 5,600 r/min, mass about 375 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-18790/18720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 18790 cone or the 18720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 55/65 kN ratings change with the cup." }, { "q": "What is the difference between 4T-18790/18720 and a metric ISO 355 tapered bearing?", "a": "4T-18790/18720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×85×17.462 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-18790/18720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 18790/18720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-18790/18720 list two speeds, 4,200 and 5,600 r/min?", "a": "The lower figure, 4,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-18790/18720 at 5,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "18790-18720", "equiv_brand": "SKF", "level": "partial", "note": "Same 50.8×85×17.462 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "18790-18724", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-18790 paired with a different cup (18724): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-18790-18720", "18790-18720", "4T-18790-18720", "18790-18720-NTN" ], "locale_variants": {} }, { "sku": "18790-18724", "brand": "NTN", "manufacturer_designation": "NTN 4T-18790/18724", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 88.9, "B_mm": 17.462, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 55, "static_load_kN": 65, "limiting_speed_rpm": 4200, "max_rpm": 4200, "speed_oil_rpm": 5600, "weight_g": 431, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-18790/18724 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 50.8×88.9×17.462 mm (assembled width T), for a shaft of about 50.8 mm (2 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 18790 sits in the pure-numeric inch family. Imperial cross-check for the drawing: 50.8×88.9×17.462 mm converts to 2 × 3.5 × 0.687 in; the ABMA envelope swaps with like-numbered inch parts but the 55/65 kN ratings are NTN-specific. Cup-side note for 18724: within the pure-numeric inch family tables the 18790 cone is listed against several cup options, and it is the cup that fixes the 88.9 mm OD and the 17.462 mm assembled width — quote the full 18790/18724 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-18790/18724 run near 4,200 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-18790/18724.", "The pure-numeric inch family at 50.8 mm bore (88.9×17.462 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 18790/18724 reference at purchase.", "Open 4T-18790/18724 sets have no seals: a hub or gearbox needs external sealing or the 4,200 r/min grease figure is meaningless once water reaches the cone rib.", "Quote the full 18790/18724 pair at ordering: the 18790 cone also ships against sibling cups, and a cup from another reference changes the 17.462 mm assembled width and the rating.", "ABMA makes the 50.8×88.9 mm envelope interchangeable, not the ratings: NTN prints 55/65 kN for this execution and another make of the same number can differ in roller complement.", "The 55/65 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-18790/18724; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-18790/18724?", "a": "4T-18790/18724 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 88.9 mm outside diameter and 17.462 mm assembled width T (3.5 × 0.687 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 55 kN, C0 65 kN, grease limiting speed 4,200 r/min, oil speed 5,600 r/min, mass about 431 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-18790/18724 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 18790 cone or the 18724 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 55/65 kN ratings change with the cup." }, { "q": "What is the difference between 4T-18790/18724 and a metric ISO 355 tapered bearing?", "a": "4T-18790/18724 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×88.9×17.462 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-18790/18724 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 18790/18724 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-18790/18724 list two speeds, 4,200 and 5,600 r/min?", "a": "The lower figure, 4,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-18790/18724 at 5,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "18790-18720", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "18790-18720-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-18790 paired with a different cup (18720): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-18790-18724", "18790-18724", "4T-18790-18724" ], "locale_variants": {} }, { "sku": "368-362A", "brand": "NTN", "manufacturer_designation": "NTN 4T-368/362A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 88.9, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 90.5, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 524, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2 in (50.8 mm) shaft position as 4T-368/362A: cone 368, cup 362A, profiled rollers and a pressed-steel cage, rated 85 kN basic dynamic and 90.5 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 368/362A without it. The 19.1 mm radial section over the 50.8 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 85/90.5 kN ratings belong to the assembled 368+362A pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 50.8 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-368/362A.", "The pure-numeric inch family at 50.8 mm bore (88.9×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 368/362A reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 20.638 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Grease packs must leave free volume inside the 20.638 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,500 r/min raises temperature and destroys the setting.", "Open 4T-368/362A sets have no seals: a hub or gearbox needs external sealing or the 4,100 r/min grease figure is meaningless once water reaches the cone rib.", "The 85/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-368/362A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-368/362A?", "a": "4T-368/362A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 88.9 mm outside diameter and 20.638 mm assembled width T (3.5 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 90.5 kN, grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 524 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-368/362A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 368 cone or the 362A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-368/362A and a metric ISO 355 tapered bearing?", "a": "4T-368/362A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×88.9×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-368/362A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 368/362A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-368/362A list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-368/362A at 5,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "368", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "368-362a", "4t-368-362a", "368-362A", "4T-368-362A" ], "locale_variants": {} }, { "sku": "370A-362A", "brand": "NTN", "manufacturer_designation": "NTN 4T-370A/362A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 88.9, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 90.5, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 516, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-370A/362A belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 370A identifies the cone of 50.8 mm (2 in) bore by catalogue lookup, and 362A fixes the 88.9 mm OD. Speed planning uses both catalogue columns: grease 4,100 r/min is the mechanical ceiling for 4T-370A/362A, oil 5,500 r/min with circulating oil — a 1,400 r/min margin at this size. Cup-side note for 362A: within the pure-numeric inch family tables the 370A cone is listed against several cup options, and it is the cup that fixes the 88.9 mm OD and the 20.638 mm assembled width — quote the full 370A/362A pair, never the cone alone. Fillet radii must clear the chamfers of the 370A cone and 362A cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-370A/362A.", "The pure-numeric inch family at 50.8 mm bore (88.9×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 370A/362A reference at purchase.", "Do not confuse T (20.638 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Quote the full 370A/362A pair at ordering: the 370A cone also ships against sibling cups, and a cup from another reference changes the 20.638 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of 370A and 362A; use undercut shoulders so the rings seat on the face, not on a radius.", "The 85/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-370A/362A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-370A/362A?", "a": "4T-370A/362A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 88.9 mm outside diameter and 20.638 mm assembled width T (3.5 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 90.5 kN, grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 516 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-370A/362A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 370A cone or the 362A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-370A/362A and a metric ISO 355 tapered bearing?", "a": "4T-370A/362A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×88.9×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-370A/362A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 370A/362A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-370A/362A list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-370A/362A at 5,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "370A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "370a-362a", "4t-370a-362a", "370A-362A", "4T-370A-362A" ], "locale_variants": {} }, { "sku": "368A-362", "brand": "NTN", "manufacturer_designation": "NTN 4T-368A/362", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 90, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 90.5, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-368A/362 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 50.8×90×20 mm (assembled width T), for a shaft of about 50.8 mm (2 in). Reading the designation: 4T-368A/362 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Contact-angle geometry of the pure-numeric inch family gives 4T-368A/362 its radial/axial load split — at 85/90.5 kN the static rating is about 1.06× C, typical of inch tapered sets proportioned for combined duty. The printed 85/90.5 kN ratings belong to the assembled 368A+362 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 50.8 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-368A/362.", "The pure-numeric inch family at 50.8 mm bore (90×20 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 368A/362 reference at purchase.", "Do not confuse T (20 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 20 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Quote the full 368A/362 pair at ordering: the 368A cone also ships against sibling cups, and a cup from another reference changes the 20 mm assembled width and the rating.", "The 85/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-368A/362; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-368A/362?", "a": "4T-368A/362 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 90 mm outside diameter and 20 mm assembled width T (3.543 × 0.787 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 90.5 kN, grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 530 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-368A/362 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 368A cone or the 362 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-368A/362 and a metric ISO 355 tapered bearing?", "a": "4T-368A/362 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×90×20 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-368A/362 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 368A/362 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-368A/362 list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-368A/362 at 5,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "368A-362A", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "368A-362X", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "368a-362", "4t-368a-362", "368A-362", "4T-368A-362" ], "locale_variants": {} }, { "sku": "28580-28521", "brand": "NTN", "manufacturer_designation": "NTN 4T-28580/28521", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 92.075, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 93, "static_load_kN": 116, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 703, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2 in (50.8 mm) shaft position as 4T-28580/28521: cone 28580, cup 28521, profiled rollers and a pressed-steel cage, rated 93 kN basic dynamic and 116 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 28580/28521 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 24.608 mm T of each 4T-28580/28521 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-28580/28521: press the 28521 cup square into the 92.075 mm seat first, then bring the 28580 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-28580/28521 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-28580/28521.", "The pure-numeric inch family at 50.8 mm bore (92.075×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28580/28521 reference at purchase.", "Do not confuse T (24.608 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "ABMA makes the 50.8×92.075 mm envelope interchangeable, not the ratings: NTN prints 93/116 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-28580/28521 near 4,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 93/116 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28580/28521; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28580/28521?", "a": "4T-28580/28521 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 92.075 mm outside diameter and 24.608 mm assembled width T (3.625 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 93 kN, C0 116 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 703 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28580/28521 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28580 cone or the 28521 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 93/116 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28580/28521 and a metric ISO 355 tapered bearing?", "a": "4T-28580/28521 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×92.075×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28580/28521 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28580/28521 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28580/28521 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28580/28521 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28580", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28580-28521", "28580-28521", "4T-28580-28521" ], "locale_variants": {} }, { "sku": "3775-3720", "brand": "NTN", "manufacturer_designation": "NTN 4T-3775/3720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 93.264, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 134, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3775/3720 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 50.8×93.264×30.162 mm (assembled width T), for a shaft of about 50.8 mm (2 in). Reading the designation: 4T-3775/3720 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 50.8×93.264×30.162 mm converts to 2 × 3.672 × 1.187 in; the ABMA envelope swaps with like-numbered inch parts but the 113/134 kN ratings are NTN-specific. Housing fitment sequence for 4T-3775/3720: press the 3720 cup square into the 93.264 mm seat first, then bring the 3775 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-3775/3720 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3775/3720.", "The pure-numeric inch family at 50.8 mm bore (93.264×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3775/3720 reference at purchase.", "An unloaded 4T-3775/3720 near 4,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 113/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3775/3720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3775/3720?", "a": "4T-3775/3720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 93.264 mm outside diameter and 30.162 mm assembled width T (3.672 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 134 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 850 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3775/3720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3775 cone or the 3720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3775/3720 and a metric ISO 355 tapered bearing?", "a": "4T-3775/3720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×93.264×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3775/3720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3775/3720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3775/3720 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3775/3720 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3775", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3775-3720", "3775-3720", "4T-3775-3720" ], "locale_variants": {} }, { "sku": "3780-3720-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-3780/3720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 93.264, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 134, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 846, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2 in (50.8 mm) shaft position as 4T-3780/3720: cone 3780, cup 3720, profiled rollers and a pressed-steel cage, rated 113 kN basic dynamic and 134 kN static. Reading the designation: 4T-3780/3720 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 50.8×93.264×30.162 mm converts to 2 × 3.672 × 1.187 in; the ABMA envelope swaps with like-numbered inch parts but the 113/134 kN ratings are NTN-specific. Cup-side note for 3720: within the pure-numeric inch family tables the 3780 cone is listed against several cup options, and it is the cup that fixes the 93.264 mm OD and the 30.162 mm assembled width — quote the full 3780/3720 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-3780/3720; reverse the fit logic when the cup rotates.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3780/3720.", "The pure-numeric inch family at 50.8 mm bore (93.264×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3780/3720 reference at purchase.", "Open 4T-3780/3720 sets have no seals: a hub or gearbox needs external sealing or the 4,000 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 50.8×93.264 mm envelope interchangeable, not the ratings: NTN prints 113/134 kN for this execution and another make of the same number can differ in roller complement.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 113/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3780/3720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3780/3720?", "a": "4T-3780/3720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 93.264 mm outside diameter and 30.162 mm assembled width T (3.672 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 134 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 846 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3780/3720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3780 cone or the 3720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3780/3720 and a metric ISO 355 tapered bearing?", "a": "4T-3780/3720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×93.264×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3780/3720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3780/3720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3780/3720 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3780/3720 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3780-3720", "equiv_brand": "SKF", "level": "partial", "note": "Same 50.8×93.264×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "3780-3726", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-3780 paired with a different cup (3726): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "3780-3732", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-3780 paired with a different cup (3732): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3780-3720", "3780-3720", "4T-3780-3720", "3780-3720-NTN" ], "locale_variants": {} }, { "sku": "33889-33821", "brand": "NTN", "manufacturer_designation": "NTN 4T-33889/33821", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 95.25, "B_mm": 27.783, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 119, "static_load_kN": 139, "limiting_speed_rpm": 3900, "max_rpm": 3900, "speed_oil_rpm": 5200, "weight_g": 878, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-33889/33821 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 50.8×95.25×27.783 mm (assembled width T), for a shaft of about 50.8 mm (2 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 33889 identifies the cone of 50.8 mm (2 in) bore by catalogue lookup, and 33821 fixes the 95.25 mm OD. The 22.2 mm radial section over the 50.8 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-33889/33821: press the 33821 cup square into the 95.25 mm seat first, then bring the 33889 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 50.8 mm cone with an induction heater (max 120 °C) and press the 95.25 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-33889/33821.", "The pure-numeric inch family at 50.8 mm bore (95.25×27.783 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 33889/33821 reference at purchase.", "Never drive the 95.25 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 4T-33889/33821 sets have no seals: a hub or gearbox needs external sealing or the 3,900 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 27.783 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 119/139 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-33889/33821; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-33889/33821?", "a": "4T-33889/33821 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 95.25 mm outside diameter and 27.783 mm assembled width T (3.75 × 1.094 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 119 kN, C0 139 kN, grease limiting speed 3,900 r/min, oil speed 5,200 r/min, mass about 878 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-33889/33821 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 33889 cone or the 33821 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 119/139 kN ratings change with the cup." }, { "q": "What is the difference between 4T-33889/33821 and a metric ISO 355 tapered bearing?", "a": "4T-33889/33821 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×95.25×27.783 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-33889/33821 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 33889/33821 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-33889/33821 list two speeds, 3,900 and 5,200 r/min?", "a": "The lower figure, 3,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-33889/33821 at 5,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "33889", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-33889-33821", "33889-33821", "4T-33889-33821" ], "locale_variants": {} }, { "sku": "3780-3726", "brand": "NTN", "manufacturer_designation": "NTN 4T-3780/3726", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 95.25, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 134, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 899, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-3780/3726 at 50.8 mm bore (2 in), 95.25 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 4,000 r/min and an oil ceiling of 5,300 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 3780/3726 without it. Contact-angle geometry of the pure-numeric inch family gives 4T-3780/3726 its radial/axial load split — at 113/134 kN the static rating is about 1.19× C, typical of inch tapered sets proportioned for combined duty. The printed 113/134 kN ratings belong to the assembled 3780+3726 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-3780/3726 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3780/3726.", "The pure-numeric inch family at 50.8 mm bore (95.25×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3780/3726 reference at purchase.", "ABMA makes the 50.8×95.25 mm envelope interchangeable, not the ratings: NTN prints 113/134 kN for this execution and another make of the same number can differ in roller complement.", "Fit selection follows the rotating ring: a rotating cone on a 50.8 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "An unloaded 4T-3780/3726 near 4,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 113/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3780/3726; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3780/3726?", "a": "4T-3780/3726 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 95.25 mm outside diameter and 30.162 mm assembled width T (3.75 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 134 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 899 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3780/3726 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3780 cone or the 3726 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3780/3726 and a metric ISO 355 tapered bearing?", "a": "4T-3780/3726 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×95.25×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3780/3726 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3780/3726 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3780/3726 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3780/3726 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3780-3720", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "3780-3720-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-3780 paired with a different cup (3720): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "3780-3732", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-3780 paired with a different cup (3732): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3780-3726", "3780-3726", "4T-3780-3726" ], "locale_variants": {} }, { "sku": "385A-382A", "brand": "NTN", "manufacturer_designation": "NTN 4T-385A/382A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 96.838, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 96.5, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 675, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-385A/382A belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-385A/382A follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Contact-angle geometry of the pure-numeric inch family gives 4T-385A/382A its radial/axial load split — at 86.5/96.5 kN the static rating is about 1.12× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-385A/382A: press the 382A cup square into the 96.838 mm seat first, then bring the 385A cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Fillet radii must clear the chamfers of the 385A cone and 382A cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-385A/382A.", "The pure-numeric inch family at 50.8 mm bore (96.838×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 385A/382A reference at purchase.", "ABMA makes the 50.8×96.838 mm envelope interchangeable, not the ratings: NTN prints 86.5/96.5 kN for this execution and another make of the same number can differ in roller complement.", "Shaft and housing fillets must clear the ring chamfers of 385A and 382A; use undercut shoulders so the rings seat on the face, not on a radius.", "Open 4T-385A/382A sets have no seals: a hub or gearbox needs external sealing or the 3,700 r/min grease figure is meaningless once water reaches the cone rib.", "The 86.5/96.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-385A/382A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-385A/382A?", "a": "4T-385A/382A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 96.838 mm outside diameter and 21 mm assembled width T (3.813 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 96.5 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 675 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-385A/382A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 385A cone or the 382A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/96.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-385A/382A and a metric ISO 355 tapered bearing?", "a": "4T-385A/382A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×96.838×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-385A/382A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 385A/382A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-385A/382A list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-385A/382A at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "385A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "385a-382a", "4t-385a-382a", "385A-382A", "4T-385A-382A" ], "locale_variants": {} }, { "sku": "28678-28622", "brand": "NTN", "manufacturer_designation": "NTN 4T-28678/28622", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 97.63, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 98, "static_load_kN": 128, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 854, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-28678/28622 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 50.8×97.63×24.608 mm (assembled width T), for a shaft of about 50.8 mm (2 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 28678 identifies the cone of 50.8 mm (2 in) bore by catalogue lookup, and 28622 fixes the 97.63 mm OD. Imperial cross-check for the drawing: 50.8×97.63×24.608 mm converts to 2 × 3.844 × 0.969 in; the ABMA envelope swaps with like-numbered inch parts but the 98/128 kN ratings are NTN-specific. Cup-side note for 28622: within the pure-numeric inch family tables the 28678 cone is listed against several cup options, and it is the cup that fixes the 97.63 mm OD and the 24.608 mm assembled width — quote the full 28678/28622 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-28678/28622 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-28678/28622.", "The pure-numeric inch family at 50.8 mm bore (97.63×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28678/28622 reference at purchase.", "Never drive the 97.63 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume inside the 24.608 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,900 r/min raises temperature and destroys the setting.", "ABMA makes the 50.8×97.63 mm envelope interchangeable, not the ratings: NTN prints 98/128 kN for this execution and another make of the same number can differ in roller complement.", "The 98/128 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28678/28622; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28678/28622?", "a": "4T-28678/28622 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 97.63 mm outside diameter and 24.608 mm assembled width T (3.844 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 98 kN, C0 128 kN, grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 854 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28678/28622 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28678 cone or the 28622 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 98/128 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28678/28622 and a metric ISO 355 tapered bearing?", "a": "4T-28678/28622 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×97.63×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28678/28622 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28678/28622 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28678/28622 list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28678/28622 at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28678", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28678-28622", "28678-28622", "4T-28678-28622" ], "locale_variants": {} }, { "sku": "3780-3732", "brand": "NTN", "manufacturer_designation": "NTN 4T-3780/3732", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 98.425, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 134, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 990, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3780/3732 is the NTN 4T catalogue entry for a 50.8×98.425×30.162 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-3780/3732 are separately stocked parts: a worn 3732 cup can be replaced against the existing 3780 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Contact-angle geometry of the pure-numeric inch family gives 4T-3780/3732 its radial/axial load split — at 113/134 kN the static rating is about 1.19× C, typical of inch tapered sets proportioned for combined duty. The printed 113/134 kN ratings belong to the assembled 3780+3732 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-3780/3732 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3780/3732.", "The pure-numeric inch family at 50.8 mm bore (98.425×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3780/3732 reference at purchase.", "ABMA makes the 50.8×98.425 mm envelope interchangeable, not the ratings: NTN prints 113/134 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 50.8×98.425 mm envelope interchangeable, not the ratings: NTN prints 113/134 kN for this execution and another make of the same number can differ in roller complement.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 113/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3780/3732; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3780/3732?", "a": "4T-3780/3732 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 98.425 mm outside diameter and 30.162 mm assembled width T (3.875 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 134 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 990 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3780/3732 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3780 cone or the 3732 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3780/3732 and a metric ISO 355 tapered bearing?", "a": "4T-3780/3732 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×98.425×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3780/3732 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3780/3732 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3780/3732 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3780/3732 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3780-3720", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "3780-3720-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-3780 paired with a different cup (3720): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "3780-3726", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-3780 paired with a different cup (3726): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=183", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3780-3732", "3780-3732", "4T-3780-3732" ], "locale_variants": {} }, { "sku": "49585-49520", "brand": "NTN", "manufacturer_designation": "NTN 4T-49585/49520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 101.6, "B_mm": 31.75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 122, "static_load_kN": 136, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 1130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-49585/49520 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 49585 and cup 49520 delivered as a matched, separable pair of 50.8 mm bore and 101.6 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 49585 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 3,700 r/min is the mechanical ceiling for 4T-49585/49520, oil 5,000 r/min with circulating oil — a 1,300 r/min margin at this size. Housing fitment sequence for 4T-49585/49520: press the 49520 cup square into the 101.6 mm seat first, then bring the 49585 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-49585/49520 run near 3,700 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-49585/49520.", "The pure-numeric inch family at 50.8 mm bore (101.6×31.75 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 49585/49520 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 49585 and 49520; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of 49585 and 49520; use undercut shoulders so the rings seat on the face, not on a radius.", "Fit selection follows the rotating ring: a rotating cone on a 50.8 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 122/136 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-49585/49520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-49585/49520?", "a": "4T-49585/49520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 101.6 mm outside diameter and 31.75 mm assembled width T (4 × 1.25 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 122 kN, C0 136 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 1130 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-49585/49520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 49585 cone or the 49520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 122/136 kN ratings change with the cup." }, { "q": "What is the difference between 4T-49585/49520 and a metric ISO 355 tapered bearing?", "a": "4T-49585/49520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×101.6×31.75 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-49585/49520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 49585/49520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-49585/49520 list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-49585/49520 at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "49585", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-49585-49520", "49585-49520", "4T-49585-49520" ], "locale_variants": {} }, { "sku": "529-522", "brand": "NTN", "manufacturer_designation": "NTN 4T-529/522", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 101.6, "B_mm": 34.925, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 150, "static_load_kN": 165, "limiting_speed_rpm": 3800, "max_rpm": 3800, "speed_oil_rpm": 5000, "weight_g": 1230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 50.8 mm carrying combined radial and thrust load, NTN lists 4T-529/522, a single-row 4T tapered roller set of 150 kN C and 165 kN C0 inside the 101.6 mm OD cup. Cone and cup of 4T-529/522 are separately stocked parts: a worn 522 cup can be replaced against the existing 529 cone, provided the new cup carries the identical reference — pairing across references changes the 34.925 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 3,800 r/min is the mechanical ceiling for 4T-529/522, oil 5,000 r/min with circulating oil — a 1,200 r/min margin at this size. The printed 150/165 kN ratings belong to the assembled 529+522 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-529/522 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-529/522.", "The pure-numeric inch family at 50.8 mm bore (101.6×34.925 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 529/522 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 529 and 522; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-529/522 near 3,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Never drive the 101.6 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 150/165 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-529/522; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-529/522?", "a": "4T-529/522 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 101.6 mm outside diameter and 34.925 mm assembled width T (4 × 1.375 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 150 kN, C0 165 kN, grease limiting speed 3,800 r/min, oil speed 5,000 r/min, mass about 1230 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-529/522 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 529 cone or the 522 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 150/165 kN ratings change with the cup." }, { "q": "What is the difference between 4T-529/522 and a metric ISO 355 tapered bearing?", "a": "4T-529/522 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×101.6×34.925 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-529/522 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 529/522 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-529/522 list two speeds, 3,800 and 5,000 r/min?", "a": "The lower figure, 3,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-529/522 at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "529", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-529-522", "529-522", "4T-529-522" ], "locale_variants": {} }, { "sku": "45284-45220", "brand": "NTN", "manufacturer_designation": "NTN 4T-45284/45220", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 104.775, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 144, "static_load_kN": 169, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-45284/45220 at 50.8 mm bore (2 in), 104.775 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 3,500 r/min and an oil ceiling of 4,700 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 45284 sits in the pure-numeric inch family. Catalogue mass of the 4T-45284/45220 cone-plus-cup set is 1240 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-45284/45220: press the 45220 cup square into the 104.775 mm seat first, then bring the 45284 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Fillet radii must clear the chamfers of the 45284 cone and 45220 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-45284/45220.", "The pure-numeric inch family at 50.8 mm bore (104.775×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 45284/45220 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ABMA makes the 50.8×104.775 mm envelope interchangeable, not the ratings: NTN prints 144/169 kN for this execution and another make of the same number can differ in roller complement.", "The 144/169 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-45284/45220; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-45284/45220?", "a": "4T-45284/45220 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 104.775 mm outside diameter and 30.162 mm assembled width T (4.125 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 144 kN, C0 169 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1240 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-45284/45220 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 45284 cone or the 45220 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 144/169 kN ratings change with the cup." }, { "q": "What is the difference between 4T-45284/45220 and a metric ISO 355 tapered bearing?", "a": "4T-45284/45220 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×104.775×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-45284/45220 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 45284/45220 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-45284/45220 list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-45284/45220 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "45284", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-45284-45220", "45284-45220", "4T-45284-45220" ], "locale_variants": {} }, { "sku": "455-453X", "brand": "NTN", "manufacturer_designation": "NTN 4T-455/453X", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 104.775, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 127, "static_load_kN": 148, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-455/453X belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-455/453X are separately stocked parts: a worn 453X cup can be replaced against the existing 455 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-455/453X enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-455/453X: press the 453X cup square into the 104.775 mm seat first, then bring the 455 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Contact-pattern check with marking blue: a pattern biased to one roller end means the 50.8 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-455/453X.", "The pure-numeric inch family at 50.8 mm bore (104.775×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 455/453X reference at purchase.", "ABMA makes the 50.8×104.775 mm envelope interchangeable, not the ratings: NTN prints 127/148 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 455/453X pair at ordering: the 455 cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 127/148 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-455/453X; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-455/453X?", "a": "4T-455/453X is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 104.775 mm outside diameter and 30.162 mm assembled width T (4.125 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 127 kN, C0 148 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1190 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-455/453X interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 455 cone or the 453X cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 127/148 kN ratings change with the cup." }, { "q": "What is the difference between 4T-455/453X and a metric ISO 355 tapered bearing?", "a": "4T-455/453X follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×104.775×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-455/453X mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 455/453X references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-455/453X list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-455/453X at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "455", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "455-453x", "4t-455-453x", "455-453X", "4T-455-453X" ], "locale_variants": {} }, { "sku": "59200-59412", "brand": "NTN", "manufacturer_designation": "NTN 4T-59200/59412", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 104.775, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 158, "static_load_kN": 178, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 1440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-59200/59412 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 59200 sits in the pure-numeric inch family. Catalogue mass of the 4T-59200/59412 cone-plus-cup set is 1440 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 59412: within the pure-numeric inch family tables the 59200 cone is listed against several cup options, and it is the cup that fixes the 104.775 mm OD and the 36.512 mm assembled width — quote the full 59200/59412 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 50.8 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-59200/59412.", "The pure-numeric inch family at 50.8 mm bore (104.775×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 59200/59412 reference at purchase.", "ABMA makes the 50.8×104.775 mm envelope interchangeable, not the ratings: NTN prints 158/178 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-59200/59412 near 3,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Quote the full 59200/59412 pair at ordering: the 59200 cone also ships against sibling cups, and a cup from another reference changes the 36.512 mm assembled width and the rating.", "The 158/178 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-59200/59412; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-59200/59412?", "a": "4T-59200/59412 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 104.775 mm outside diameter and 36.512 mm assembled width T (4.125 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 158 kN, C0 178 kN, grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 1440 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-59200/59412 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 59200 cone or the 59412 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 158/178 kN ratings change with the cup." }, { "q": "What is the difference between 4T-59200/59412 and a metric ISO 355 tapered bearing?", "a": "4T-59200/59412 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×104.775×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-59200/59412 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 59200/59412 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-59200/59412 list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-59200/59412 at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "59200", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-59200-59412", "59200-59412", "4T-59200-59412" ], "locale_variants": {} }, { "sku": "HM807046-HM807010", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM807046/HM807010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 104.775, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 189, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 1480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM807046/HM807010 is the NTN 4T catalogue entry for a 50.8×104.775×36.512 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote HM807046/HM807010 without it. Catalogue mass of the 4T-HM807046/HM807010 cone-plus-cup set is 1480 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-HM807046/HM807010: press the HM807010 cup square into the 104.775 mm seat first, then bring the HM807046 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-HM807046/HM807010, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM807046/HM807010.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 50.8 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Shaft and housing fillets must clear the ring chamfers of HM807046 and HM807010; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of HM807046 and HM807010; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full HM807046/HM807010 pair at ordering: the HM807046 cone also ships against sibling cups, and a cup from another reference changes the 36.512 mm assembled width and the rating.", "The 153/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM807046/HM807010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM807046/HM807010?", "a": "4T-HM807046/HM807010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 104.775 mm outside diameter and 36.512 mm assembled width T (4.125 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 189 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1480 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM807046/HM807010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM807046 cone or the HM807010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM807046/HM807010 and a metric ISO 355 tapered bearing?", "a": "4T-HM807046/HM807010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×104.775×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM807046/HM807010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM807046/HM807010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM807046/HM807010 list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM807046/HM807010 at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM807046-010", "equiv_brand": "SKF", "level": "partial", "note": "Same 50.8×104.775×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm807046-hm807010", "hm807046-hm807010", "HM807046-HM807010", "4T-HM807046-HM807010" ], "locale_variants": {} }, { "sku": "537-532X-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-537/532X", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 107.95, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 157, "static_load_kN": 177, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 1550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-537/532X denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 537 and cup 532X delivered as a matched, separable pair of 50.8 mm bore and 107.95 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 537 identifies the cone of 50.8 mm (2 in) bore by catalogue lookup, and 532X fixes the 107.95 mm OD. Catalogue mass of the 4T-537/532X cone-plus-cup set is 1550 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-537/532X: press the 532X cup square into the 107.95 mm seat first, then bring the 537 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 50.8 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-537/532X.", "The pure-numeric inch family at 50.8 mm bore (107.95×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 537/532X reference at purchase.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-537/532X sets have no seals: a hub or gearbox needs external sealing or the 3,600 r/min grease figure is meaningless once water reaches the cone rib.", "Fit selection follows the rotating ring: a rotating cone on a 50.8 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 157/177 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-537/532X; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-537/532X?", "a": "4T-537/532X is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 107.95 mm outside diameter and 36.512 mm assembled width T (4.25 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 157 kN, C0 177 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1550 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-537/532X interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 537 cone or the 532X cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 157/177 kN ratings change with the cup." }, { "q": "What is the difference between 4T-537/532X and a metric ISO 355 tapered bearing?", "a": "4T-537/532X follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×107.95×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-537/532X mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 537/532X references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-537/532X list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-537/532X at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "537-532X", "equiv_brand": "SKF", "level": "partial", "note": "Same 50.8×107.95×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-537-532x", "537-532x", "537-532X", "4T-537-532X", "537-532X-NTN" ], "locale_variants": {} }, { "sku": "HM907643-HM907614", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM907643/HM907614", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 111.125, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 115, "static_load_kN": 136, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1360, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM907643/HM907614 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-HM907643/HM907614 are separately stocked parts: a worn HM907614 cup can be replaced against the existing HM907643 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Imperial cross-check for the drawing: 50.8×111.125×30.162 mm converts to 2 × 4.375 × 1.187 in; the ABMA envelope swaps with like-numbered inch parts but the 115/136 kN ratings are NTN-specific. The printed 115/136 kN ratings belong to the assembled HM907643+HM907614 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 50.8 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM907643/HM907614.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 50.8 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-HM907643/HM907614 sets have no seals: a hub or gearbox needs external sealing or the 3,200 r/min grease figure is meaningless once water reaches the cone rib.", "Never drive the 111.125 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 115/136 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM907643/HM907614; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM907643/HM907614?", "a": "4T-HM907643/HM907614 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 111.125 mm outside diameter and 30.162 mm assembled width T (4.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 115 kN, C0 136 kN, grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1360 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM907643/HM907614 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM907643 cone or the HM907614 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 115/136 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM907643/HM907614 and a metric ISO 355 tapered bearing?", "a": "4T-HM907643/HM907614 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×111.125×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM907643/HM907614 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM907643/HM907614 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM907643/HM907614 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM907643/HM907614 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM907643", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm907643-hm907614", "hm907643-hm907614", "HM907643-HM907614", "4T-HM907643-HM907614" ], "locale_variants": {} }, { "sku": "39575-39520", "brand": "NTN", "manufacturer_designation": "NTN 4T-39575/39520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 195, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1540, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 50.8 mm carrying combined radial and thrust load, NTN lists 4T-39575/39520, a single-row 4T tapered roller set of 153 kN C and 195 kN C0 inside the 112.712 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 39575/39520 without it. Speed planning uses both catalogue columns: grease 3,200 r/min is the mechanical ceiling for 4T-39575/39520, oil 4,200 r/min with circulating oil — a 1,000 r/min margin at this size. Housing fitment sequence for 4T-39575/39520: press the 39520 cup square into the 112.712 mm seat first, then bring the 39575 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-39575/39520 run near 3,200 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-39575/39520.", "The pure-numeric inch family at 50.8 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 39575/39520 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 50.8 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,200 r/min raises temperature and destroys the setting.", "An unloaded 4T-39575/39520 near 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 153/195 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-39575/39520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-39575/39520?", "a": "4T-39575/39520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 195 kN, grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1540 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-39575/39520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 39575 cone or the 39520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/195 kN ratings change with the cup." }, { "q": "What is the difference between 4T-39575/39520 and a metric ISO 355 tapered bearing?", "a": "4T-39575/39520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-39575/39520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 39575/39520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-39575/39520 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-39575/39520 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "39575", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-39575-39520", "39575-39520", "4T-39575-39520" ], "locale_variants": {} }, { "sku": "3975-3920", "brand": "NTN", "manufacturer_designation": "NTN 4T-3975/3920", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 132, "static_load_kN": 174, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 1530, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-3975/3920 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 3975 and cup 3920 delivered as a matched, separable pair of 50.8 mm bore and 112.712 mm outside diameter. Cone and cup of 4T-3975/3920 are separately stocked parts: a worn 3920 cup can be replaced against the existing 3975 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-3975/3920 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-3975/3920: press the 3920 cup square into the 112.712 mm seat first, then bring the 3975 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Fillet radii must clear the chamfers of the 3975 cone and 3920 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3975/3920.", "The pure-numeric inch family at 50.8 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3975/3920 reference at purchase.", "An unloaded 4T-3975/3920 near 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ABMA makes the 50.8×112.712 mm envelope interchangeable, not the ratings: NTN prints 132/174 kN for this execution and another make of the same number can differ in roller complement.", "The 132/174 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3975/3920; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3975/3920?", "a": "4T-3975/3920 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 132 kN, C0 174 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 1530 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3975/3920 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3975 cone or the 3920 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 132/174 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3975/3920 and a metric ISO 355 tapered bearing?", "a": "4T-3975/3920 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3975/3920 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3975/3920 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3975/3920 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3975/3920 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3975", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3975-3920", "3975-3920", "4T-3975-3920" ], "locale_variants": {} }, { "sku": "55200C-55443", "brand": "NTN", "manufacturer_designation": "NTN 4T-55200C/55443", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 115, "static_load_kN": 136, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-55200C/55443 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-55200C/55443 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 2.3 kN of dynamic capacity per millimetre of bore summarises the 115 kN rating over the 50.8 mm bore — sanity-check any interchange candidate against this ratio and the 30.162 mm T. The printed 115/136 kN ratings belong to the assembled 55200C+55443 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-55200C/55443 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-55200C/55443.", "The pure-numeric inch family at 50.8 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 55200C/55443 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 50.8 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of 55200C and 55443; use undercut shoulders so the rings seat on the face, not on a radius.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 115/136 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-55200C/55443; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-55200C/55443?", "a": "4T-55200C/55443 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 115 kN, C0 136 kN, grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1340 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-55200C/55443 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 55200C cone or the 55443 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 115/136 kN ratings change with the cup." }, { "q": "What is the difference between 4T-55200C/55443 and a metric ISO 355 tapered bearing?", "a": "4T-55200C/55443 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-55200C/55443 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 55200C/55443 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-55200C/55443 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-55200C/55443 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "55200C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-55200c-55443", "55200c-55443", "55200C-55443", "4T-55200C-55443" ], "locale_variants": {} }, { "sku": "66200-66462", "brand": "NTN", "manufacturer_designation": "NTN 4T-66200/66462", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 117.475, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 144, "static_load_kN": 153, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4400, "weight_g": 1680, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-66200/66462 is the NTN 4T catalogue entry for a 50.8×117.475×33.338 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 66200 identifies the cone of 50.8 mm (2 in) bore by catalogue lookup, and 66462 fixes the 117.475 mm OD. The 33.3 mm radial section over the 50.8 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-66200/66462: press the 66462 cup square into the 117.475 mm seat first, then bring the 66200 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-66200/66462 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-66200/66462.", "The pure-numeric inch family at 50.8 mm bore (117.475×33.338 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 66200/66462 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 50.8 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 50.8×117.475 mm envelope interchangeable, not the ratings: NTN prints 144/153 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-66200/66462 near 3,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 144/153 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-66200/66462; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-66200/66462?", "a": "4T-66200/66462 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 117.475 mm outside diameter and 33.338 mm assembled width T (4.625 × 1.313 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 144 kN, C0 153 kN, grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 1680 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-66200/66462 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 66200 cone or the 66462 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 144/153 kN ratings change with the cup." }, { "q": "What is the difference between 4T-66200/66462 and a metric ISO 355 tapered bearing?", "a": "4T-66200/66462 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×117.475×33.338 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-66200/66462 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 66200/66462 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-66200/66462 list two speeds, 3,300 and 4,400 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-66200/66462 at 4,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "66200", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-66200-66462", "66200-66462", "4T-66200-66462" ], "locale_variants": {} }, { "sku": "619-612", "brand": "NTN", "manufacturer_designation": "NTN 4T-619/612", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 120.65, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 190, "static_load_kN": 213, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4400, "weight_g": 2300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 50.8 mm carrying combined radial and thrust load, NTN lists 4T-619/612, a single-row 4T tapered roller set of 190 kN C and 213 kN C0 inside the 120.65 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 619/612 without it. Contact-angle geometry of the pure-numeric inch family gives 4T-619/612 its radial/axial load split — at 190/213 kN the static rating is about 1.12× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-619/612: press the 612 cup square into the 120.65 mm seat first, then bring the 619 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-619/612 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-619/612.", "The pure-numeric inch family at 50.8 mm bore (120.65×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 619/612 reference at purchase.", "ABMA makes the 50.8×120.65 mm envelope interchangeable, not the ratings: NTN prints 190/213 kN for this execution and another make of the same number can differ in roller complement.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-619/612 sets have no seals: a hub or gearbox needs external sealing or the 3,300 r/min grease figure is meaningless once water reaches the cone rib.", "The 190/213 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-619/612; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-619/612?", "a": "4T-619/612 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 120.65 mm outside diameter and 41.275 mm assembled width T (4.75 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 190 kN, C0 213 kN, grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 2300 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-619/612 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 619 cone or the 612 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 190/213 kN ratings change with the cup." }, { "q": "What is the difference between 4T-619/612 and a metric ISO 355 tapered bearing?", "a": "4T-619/612 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×120.65×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-619/612 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 619/612 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-619/612 list two speeds, 3,300 and 4,400 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-619/612 at 4,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "619", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-619-612", "619-612", "4T-619-612" ], "locale_variants": {} }, { "sku": "555-552A", "brand": "NTN", "manufacturer_designation": "NTN 4T-555/552A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 123.825, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 175, "static_load_kN": 216, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4100, "weight_g": 2340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-555/552A denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 555 and cup 552A delivered as a matched, separable pair of 50.8 mm bore and 123.825 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 555/552A without it. Speed planning uses both catalogue columns: grease 3,000 r/min is the mechanical ceiling for 4T-555/552A, oil 4,100 r/min with circulating oil — a 1,100 r/min margin at this size. Cup-side note for 552A: within the pure-numeric inch family tables the 555 cone is listed against several cup options, and it is the cup that fixes the 123.825 mm OD and the 38.1 mm assembled width — quote the full 555/552A pair, never the cone alone. Running clearance of 4T-555/552A is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-555/552A.", "The pure-numeric inch family at 50.8 mm bore (123.825×38.1 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 555/552A reference at purchase.", "Never drive the 123.825 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume inside the 38.1 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,100 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of 555 and 552A; use undercut shoulders so the rings seat on the face, not on a radius.", "The 175/216 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-555/552A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-555/552A?", "a": "4T-555/552A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 123.825 mm outside diameter and 38.1 mm assembled width T (4.875 × 1.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 175 kN, C0 216 kN, grease limiting speed 3,000 r/min, oil speed 4,100 r/min, mass about 2340 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-555/552A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 555 cone or the 552A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 175/216 kN ratings change with the cup." }, { "q": "What is the difference between 4T-555/552A and a metric ISO 355 tapered bearing?", "a": "4T-555/552A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×123.825×38.1 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-555/552A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 555/552A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-555/552A list two speeds, 3,000 and 4,100 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-555/552A at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "555", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-555-552a", "555-552a", "555-552A", "4T-555-552A" ], "locale_variants": {} }, { "sku": "72200C-72487", "brand": "NTN", "manufacturer_designation": "NTN 4T-72200C/72487", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 50.8, "D_mm": 123.825, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 171, "static_load_kN": 188, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3900, "weight_g": 2100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 50.8 mm carrying combined radial and thrust load, NTN lists 4T-72200C/72487, a single-row 4T tapered roller set of 171 kN C and 188 kN C0 inside the 123.825 mm OD cup. Cone and cup of 4T-72200C/72487 are separately stocked parts: a worn 72487 cup can be replaced against the existing 72200C cone, provided the new cup carries the identical reference — pairing across references changes the 36.512 mm assembled width and the rating. Contact-angle geometry of the pure-numeric inch family gives 4T-72200C/72487 its radial/axial load split — at 171/188 kN the static rating is about 1.10× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 72487: within the pure-numeric inch family tables the 72200C cone is listed against several cup options, and it is the cup that fixes the 123.825 mm OD and the 36.512 mm assembled width — quote the full 72200C/72487 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-72200C/72487 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 50.8 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-72200C/72487.", "The pure-numeric inch family at 50.8 mm bore (123.825×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 72200C/72487 reference at purchase.", "Inch and metric bores collide on paper — 50.8 mm is 2 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 50.8 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "An unloaded 4T-72200C/72487 near 2,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 171/188 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-72200C/72487; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-72200C/72487?", "a": "4T-72200C/72487 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 123.825 mm outside diameter and 36.512 mm assembled width T (4.875 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 171 kN, C0 188 kN, grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 2100 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-72200C/72487 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 72200C cone or the 72487 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 171/188 kN ratings change with the cup." }, { "q": "What is the difference between 4T-72200C/72487 and a metric ISO 355 tapered bearing?", "a": "4T-72200C/72487 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 50.8×123.825×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-72200C/72487 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 72200C/72487 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-72200C/72487 list two speeds, 2,900 and 3,900 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-72200C/72487 at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "72200C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-72200c-72487", "72200c-72487", "72200C-72487", "4T-72200C-72487" ], "locale_variants": {} }, { "sku": "368S-362A", "brand": "NTN", "manufacturer_designation": "NTN 4T-368S/362A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 51.592, "D_mm": 88.9, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 85, "static_load_kN": 90.5, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 512, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-368S/362A denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 368S and cup 362A delivered as a matched, separable pair of 51.592 mm bore and 88.9 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 368S identifies the cone of 51.592 mm (2.031 in) bore by catalogue lookup, and 362A fixes the 88.9 mm OD. Imperial cross-check for the drawing: 51.592×88.9×20.638 mm converts to 2.031 × 3.5 × 0.813 in; the ABMA envelope swaps with like-numbered inch parts but the 85/90.5 kN ratings are NTN-specific. Cup-side note for 362A: within the pure-numeric inch family tables the 368S cone is listed against several cup options, and it is the cup that fixes the 88.9 mm OD and the 20.638 mm assembled width — quote the full 368S/362A pair, never the cone alone. Running clearance of 4T-368S/362A is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 51.592 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-368S/362A.", "The pure-numeric inch family at 51.592 mm bore (88.9×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 368S/362A reference at purchase.", "Do not confuse T (20.638 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 20.638 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-368S/362A sets have no seals: a hub or gearbox needs external sealing or the 4,100 r/min grease figure is meaningless once water reaches the cone rib.", "The 85/90.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-368S/362A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-368S/362A?", "a": "4T-368S/362A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 51.592 mm bore (2.031 in), 88.9 mm outside diameter and 20.638 mm assembled width T (3.5 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 85 kN, C0 90.5 kN, grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 512 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-368S/362A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 368S cone or the 362A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 85/90.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-368S/362A and a metric ISO 355 tapered bearing?", "a": "4T-368S/362A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 51.592×88.9×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-368S/362A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 368S/362A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-368S/362A list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-368S/362A at 5,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "368S", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "368s-362a", "4t-368s-362a", "368S-362A", "4T-368S-362A" ], "locale_variants": {} }, { "sku": "28584-28521", "brand": "NTN", "manufacturer_designation": "NTN 4T-28584/28521", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 52.388, "D_mm": 92.075, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 93, "static_load_kN": 116, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 703, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-28584/28521 at 52.388 mm bore (2.063 in), 92.075 mm cup OD and 24.608 mm assembled T, with a grease limiting speed of 4,000 r/min and an oil ceiling of 5,300 r/min. Reading the designation: 4T-28584/28521 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 52.388×92.075×24.608 mm converts to 2.063 × 3.625 × 0.969 in; the ABMA envelope swaps with like-numbered inch parts but the 93/116 kN ratings are NTN-specific. Cup-side note for 28521: within the pure-numeric inch family tables the 28584 cone is listed against several cup options, and it is the cup that fixes the 92.075 mm OD and the 24.608 mm assembled width — quote the full 28584/28521 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-28584/28521 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 52.388 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-28584/28521.", "The pure-numeric inch family at 52.388 mm bore (92.075×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28584/28521 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 24.608 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 52.388 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 24.608 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,300 r/min raises temperature and destroys the setting.", "The 93/116 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28584/28521; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28584/28521?", "a": "4T-28584/28521 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 52.388 mm bore (2.063 in), 92.075 mm outside diameter and 24.608 mm assembled width T (3.625 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 93 kN, C0 116 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 703 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28584/28521 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28584 cone or the 28521 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 93/116 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28584/28521 and a metric ISO 355 tapered bearing?", "a": "4T-28584/28521 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 52.388×92.075×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28584/28521 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28584/28521 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28584/28521 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28584/28521 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28584", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28584-28521", "28584-28521", "4T-28584-28521" ], "locale_variants": {} }, { "sku": "3767-3720", "brand": "NTN", "manufacturer_designation": "NTN 4T-3767/3720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 52.388, "D_mm": 93.264, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 134, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 817, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3767/3720 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 3767 sits in the pure-numeric inch family. Catalogue mass of the 4T-3767/3720 cone-plus-cup set is 817 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 3720: within the pure-numeric inch family tables the 3767 cone is listed against several cup options, and it is the cup that fixes the 93.264 mm OD and the 30.162 mm assembled width — quote the full 3767/3720 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-3767/3720 run near 4,000 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 52.388 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-3767/3720.", "The pure-numeric inch family at 52.388 mm bore (93.264×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3767/3720 reference at purchase.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,300 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 52.388 mm is 2.063 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,300 r/min raises temperature and destroys the setting.", "The 113/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3767/3720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3767/3720?", "a": "4T-3767/3720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 52.388 mm bore (2.063 in), 93.264 mm outside diameter and 30.162 mm assembled width T (3.672 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 134 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 817 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3767/3720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3767 cone or the 3720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3767/3720 and a metric ISO 355 tapered bearing?", "a": "4T-3767/3720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 52.388×93.264×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3767/3720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3767/3720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3767/3720 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3767/3720 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3767", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3767-3720", "3767-3720", "4T-3767-3720" ], "locale_variants": {} }, { "sku": "33890-33821", "brand": "NTN", "manufacturer_designation": "NTN 4T-33890/33821", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 52.388, "D_mm": 95.25, "B_mm": 27.783, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 119, "static_load_kN": 139, "limiting_speed_rpm": 3900, "max_rpm": 3900, "speed_oil_rpm": 5200, "weight_g": 851, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-33890/33821 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 33890/33821 without it. The 21.4 mm radial section over the 52.388 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-33890/33821: press the 33821 cup square into the 95.25 mm seat first, then bring the 33890 cone (on its 52.388 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-33890/33821, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 52.388 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-33890/33821.", "The pure-numeric inch family at 52.388 mm bore (95.25×27.783 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 33890/33821 reference at purchase.", "Do not confuse T (27.783 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Never drive the 95.25 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Inch and metric bores collide on paper — 52.388 mm is 2.063 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 119/139 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-33890/33821; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-33890/33821?", "a": "4T-33890/33821 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 52.388 mm bore (2.063 in), 95.25 mm outside diameter and 27.783 mm assembled width T (3.75 × 1.094 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 119 kN, C0 139 kN, grease limiting speed 3,900 r/min, oil speed 5,200 r/min, mass about 851 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-33890/33821 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 33890 cone or the 33821 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 119/139 kN ratings change with the cup." }, { "q": "What is the difference between 4T-33890/33821 and a metric ISO 355 tapered bearing?", "a": "4T-33890/33821 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 52.388×95.25×27.783 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-33890/33821 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 33890/33821 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-33890/33821 list two speeds, 3,900 and 5,200 r/min?", "a": "The lower figure, 3,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-33890/33821 at 5,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "33890", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-33890-33821", "33890-33821", "4T-33890-33821" ], "locale_variants": {} }, { "sku": "LM806649-LM806610", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM806649/LM806610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 88.9, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 67.5, "static_load_kN": 82.5, "limiting_speed_rpm": 4000, "max_rpm": 4000, "speed_oil_rpm": 5300, "weight_g": 437, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 53.975 mm carrying combined radial and thrust load, NTN lists 4T-LM806649/LM806610, a single-row 4T tapered roller set of 67.5 kN C and 82.5 kN C0 inside the 88.9 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — LM806649 sits in the light-medium LM family. The 17.5 mm radial section over the 53.975 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-LM806649/LM806610: press the LM806610 cup square into the 88.9 mm seat first, then bring the LM806649 cone (on its 53.975 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-LM806649/LM806610 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-LM806649/LM806610.", "The light-medium LM family at 53.975 mm bore (88.9×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM806649/LM806610 reference at purchase.", "ABMA makes the 53.975×88.9 mm envelope interchangeable, not the ratings: NTN prints 67.5/82.5 kN for this execution and another make of the same number can differ in roller complement.", "Never drive the 88.9 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Shaft and housing fillets must clear the ring chamfers of LM806649 and LM806610; use undercut shoulders so the rings seat on the face, not on a radius.", "The 67.5/82.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM806649/LM806610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM806649/LM806610?", "a": "4T-LM806649/LM806610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 88.9 mm outside diameter and 19.05 mm assembled width T (3.5 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 67.5 kN, C0 82.5 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 437 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM806649/LM806610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM806649 cone or the LM806610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 67.5/82.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM806649/LM806610 and a metric ISO 355 tapered bearing?", "a": "4T-LM806649/LM806610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×88.9×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM806649/LM806610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM806649/LM806610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM806649/LM806610 list two speeds, 4,000 and 5,300 r/min?", "a": "The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM806649/LM806610 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM806649-610", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm806649-lm806610", "lm806649-lm806610", "LM806649-LM806610", "4T-LM806649-LM806610" ], "locale_variants": {} }, { "sku": "33895-33822-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-33895/33822", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 95.25, "B_mm": 27.783, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 119, "static_load_kN": 139, "limiting_speed_rpm": 3900, "max_rpm": 3900, "speed_oil_rpm": 5200, "weight_g": 823, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.125 in (53.975 mm) shaft position as 4T-33895/33822: cone 33895, cup 33822, profiled rollers and a pressed-steel cage, rated 119 kN basic dynamic and 139 kN static. Cone and cup of 4T-33895/33822 are separately stocked parts: a worn 33822 cup can be replaced against the existing 33895 cone, provided the new cup carries the identical reference — pairing across references changes the 27.783 mm assembled width and the rating. Imperial cross-check for the drawing: 53.975×95.25×27.783 mm converts to 2.125 × 3.75 × 1.094 in; the ABMA envelope swaps with like-numbered inch parts but the 119/139 kN ratings are NTN-specific. The printed 119/139 kN ratings belong to the assembled 33895+33822 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-33895/33822 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-33895/33822.", "The pure-numeric inch family at 53.975 mm bore (95.25×27.783 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 33895/33822 reference at purchase.", "An unloaded 4T-33895/33822 near 3,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Fit selection follows the rotating ring: a rotating cone on a 53.975 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 33895/33822 pair at ordering: the 33895 cone also ships against sibling cups, and a cup from another reference changes the 27.783 mm assembled width and the rating.", "The 119/139 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-33895/33822; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-33895/33822?", "a": "4T-33895/33822 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 95.25 mm outside diameter and 27.783 mm assembled width T (3.75 × 1.094 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 119 kN, C0 139 kN, grease limiting speed 3,900 r/min, oil speed 5,200 r/min, mass about 823 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-33895/33822 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 33895 cone or the 33822 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 119/139 kN ratings change with the cup." }, { "q": "What is the difference between 4T-33895/33822 and a metric ISO 355 tapered bearing?", "a": "4T-33895/33822 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×95.25×27.783 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-33895/33822 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 33895/33822 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-33895/33822 list two speeds, 3,900 and 5,200 r/min?", "a": "The lower figure, 3,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-33895/33822 at 5,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "33895-33821", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "33895-33822", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-33895-33822", "33895-33822", "4T-33895-33822", "33895-33822-NTN" ], "locale_variants": {} }, { "sku": "389A-382A", "brand": "NTN", "manufacturer_designation": "NTN 4T-389A/382A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 96.838, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 96.5, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 632, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-389A/382A denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 389A and cup 382A delivered as a matched, separable pair of 53.975 mm bore and 96.838 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 389A sits in the pure-numeric inch family. The 1.6 kN of dynamic capacity per millimetre of bore summarises the 86.5 kN rating over the 53.975 mm bore — sanity-check any interchange candidate against this ratio and the 21 mm T. Cup-side note for 382A: within the pure-numeric inch family tables the 389A cone is listed against several cup options, and it is the cup that fixes the 96.838 mm OD and the 21 mm assembled width — quote the full 389A/382A pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-389A/382A, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-389A/382A.", "The pure-numeric inch family at 53.975 mm bore (96.838×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 389A/382A reference at purchase.", "An unloaded 4T-389A/382A near 3,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Open 4T-389A/382A sets have no seals: a hub or gearbox needs external sealing or the 3,700 r/min grease figure is meaningless once water reaches the cone rib.", "Do not confuse T (21 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 86.5/96.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-389A/382A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-389A/382A?", "a": "4T-389A/382A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 96.838 mm outside diameter and 21 mm assembled width T (3.813 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 96.5 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 632 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-389A/382A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 389A cone or the 382A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/96.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-389A/382A and a metric ISO 355 tapered bearing?", "a": "4T-389A/382A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×96.838×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-389A/382A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 389A/382A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-389A/382A list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-389A/382A at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "389A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "389a-382a", "4t-389a-382a", "389A-382A", "4T-389A-382A" ], "locale_variants": {} }, { "sku": "45287-45220", "brand": "NTN", "manufacturer_designation": "NTN 4T-45287/45220", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 104.775, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 144, "static_load_kN": 169, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 53.975 mm carrying combined radial and thrust load, NTN lists 4T-45287/45220, a single-row 4T tapered roller set of 144 kN C and 169 kN C0 inside the 104.775 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 45287 identifies the cone of 53.975 mm (2.125 in) bore by catalogue lookup, and 45220 fixes the 104.775 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-45287/45220 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-45287/45220: press the 45220 cup square into the 104.775 mm seat first, then bring the 45287 cone (on its 53.975 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 53.975 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-45287/45220.", "The pure-numeric inch family at 53.975 mm bore (104.775×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 45287/45220 reference at purchase.", "Never drive the 104.775 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Fit selection follows the rotating ring: a rotating cone on a 53.975 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of 45287 and 45220; use undercut shoulders so the rings seat on the face, not on a radius.", "The 144/169 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-45287/45220; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-45287/45220?", "a": "4T-45287/45220 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 104.775 mm outside diameter and 30.162 mm assembled width T (4.125 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 144 kN, C0 169 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1170 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-45287/45220 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 45287 cone or the 45220 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 144/169 kN ratings change with the cup." }, { "q": "What is the difference between 4T-45287/45220 and a metric ISO 355 tapered bearing?", "a": "4T-45287/45220 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×104.775×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-45287/45220 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 45287/45220 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-45287/45220 list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-45287/45220 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "45287", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-45287-45220", "45287-45220", "4T-45287-45220" ], "locale_variants": {} }, { "sku": "HM807049-HM807010", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM807049/HM807010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 104.775, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 189, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 1410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 53.975 mm carrying combined radial and thrust load, NTN lists 4T-HM807049/HM807010, a single-row 4T tapered roller set of 153 kN C and 189 kN C0 inside the 104.775 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HM807049 sits in the heavy-medium HM family. Catalogue mass of the 4T-HM807049/HM807010 cone-plus-cup set is 1410 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for HM807010: within the heavy-medium HM family tables the HM807049 cone is listed against several cup options, and it is the cup that fixes the 104.775 mm OD and the 36.512 mm assembled width — quote the full HM807049/HM807010 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-HM807049/HM807010 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM807049/HM807010.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 53.975 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Inch and metric bores collide on paper — 53.975 mm is 2.125 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-HM807049/HM807010 sets have no seals: a hub or gearbox needs external sealing or the 3,600 r/min grease figure is meaningless once water reaches the cone rib.", "Grease packs must leave free volume inside the 36.512 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,800 r/min raises temperature and destroys the setting.", "The 153/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM807049/HM807010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM807049/HM807010?", "a": "4T-HM807049/HM807010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 104.775 mm outside diameter and 36.512 mm assembled width T (4.125 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 189 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1410 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM807049/HM807010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM807049 cone or the HM807010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM807049/HM807010 and a metric ISO 355 tapered bearing?", "a": "4T-HM807049/HM807010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×104.775×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM807049/HM807010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM807049/HM807010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM807049/HM807010 list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM807049/HM807010 at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM807049", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm807049-hm807010", "hm807049-hm807010", "HM807049-HM807010", "4T-HM807049-HM807010" ], "locale_variants": {} }, { "sku": "539-532X-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-539/532X", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 107.95, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 157, "static_load_kN": 177, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 1470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-539/532X at 53.975 mm bore (2.125 in), 107.95 mm cup OD and 36.512 mm assembled T, with a grease limiting speed of 3,600 r/min and an oil ceiling of 4,800 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 539 sits in the pure-numeric inch family. Imperial cross-check for the drawing: 53.975×107.95×36.512 mm converts to 2.125 × 4.25 × 1.437 in; the ABMA envelope swaps with like-numbered inch parts but the 157/177 kN ratings are NTN-specific. Housing fitment sequence for 4T-539/532X: press the 532X cup square into the 107.95 mm seat first, then bring the 539 cone (on its 53.975 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-539/532X, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-539/532X.", "The pure-numeric inch family at 53.975 mm bore (107.95×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 539/532X reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 36.512 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 53.975 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Open 4T-539/532X sets have no seals: a hub or gearbox needs external sealing or the 3,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 157/177 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-539/532X; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-539/532X?", "a": "4T-539/532X is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 107.95 mm outside diameter and 36.512 mm assembled width T (4.25 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 157 kN, C0 177 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1470 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-539/532X interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 539 cone or the 532X cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 157/177 kN ratings change with the cup." }, { "q": "What is the difference between 4T-539/532X and a metric ISO 355 tapered bearing?", "a": "4T-539/532X follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×107.95×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-539/532X mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 539/532X references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-539/532X list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-539/532X at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "539-532A", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "539-532X", "equiv_brand": "SKF", "level": "partial", "note": "Same 53.975×107.95×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-539-532x", "539-532x", "539-532X", "4T-539-532X", "539-532X-NTN" ], "locale_variants": {} }, { "sku": "621-612", "brand": "NTN", "manufacturer_designation": "NTN 4T-621/612", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 120.65, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 190, "static_load_kN": 213, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4400, "weight_g": 2220, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-621/612 is the NTN 4T catalogue entry for a 53.975×120.65×41.275 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Reading the designation: 4T-621/612 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Catalogue mass of the 4T-621/612 cone-plus-cup set is 2220 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 612: within the pure-numeric inch family tables the 621 cone is listed against several cup options, and it is the cup that fixes the 120.65 mm OD and the 41.275 mm assembled width — quote the full 621/612 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-621/612 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-621/612.", "The pure-numeric inch family at 53.975 mm bore (120.65×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 621/612 reference at purchase.", "ABMA makes the 53.975×120.65 mm envelope interchangeable, not the ratings: NTN prints 190/213 kN for this execution and another make of the same number can differ in roller complement.", "Inch and metric bores collide on paper — 53.975 mm is 2.125 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 190/213 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-621/612; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-621/612?", "a": "4T-621/612 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 120.65 mm outside diameter and 41.275 mm assembled width T (4.75 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 190 kN, C0 213 kN, grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 2220 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-621/612 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 621 cone or the 612 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 190/213 kN ratings change with the cup." }, { "q": "What is the difference between 4T-621/612 and a metric ISO 355 tapered bearing?", "a": "4T-621/612 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×120.65×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-621/612 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 621/612 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-621/612 list two speeds, 3,300 and 4,400 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-621/612 at 4,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "621", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-621-612", "621-612", "4T-621-612" ], "locale_variants": {} }, { "sku": "5578-5535", "brand": "NTN", "manufacturer_designation": "NTN 4T-5578/5535", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 122.238, "B_mm": 43.658, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 215, "static_load_kN": 283, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 2640, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 53.975 mm carrying combined radial and thrust load, NTN lists 4T-5578/5535, a single-row 4T tapered roller set of 215 kN C and 283 kN C0 inside the 122.238 mm OD cup. Cone and cup of 4T-5578/5535 are separately stocked parts: a worn 5535 cup can be replaced against the existing 5578 cone, provided the new cup carries the identical reference — pairing across references changes the 43.658 mm assembled width and the rating. Imperial cross-check for the drawing: 53.975×122.238×43.658 mm converts to 2.125 × 4.813 × 1.719 in; the ABMA envelope swaps with like-numbered inch parts but the 215/283 kN ratings are NTN-specific. Cup-side note for 5535: within the pure-numeric inch family tables the 5578 cone is listed against several cup options, and it is the cup that fixes the 122.238 mm OD and the 43.658 mm assembled width — quote the full 5578/5535 pair, never the cone alone. Mount the 53.975 mm cone with an induction heater (max 120 °C) and press the 122.238 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-5578/5535.", "The pure-numeric inch family at 53.975 mm bore (122.238×43.658 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 5578/5535 reference at purchase.", "Quote the full 5578/5535 pair at ordering: the 5578 cone also ships against sibling cups, and a cup from another reference changes the 43.658 mm assembled width and the rating.", "Replacing one half of an adjusted pair without resetting end play negates the 43.658 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (43.658 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 215/283 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-5578/5535; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-5578/5535?", "a": "4T-5578/5535 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 122.238 mm outside diameter and 43.658 mm assembled width T (4.813 × 1.719 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 215 kN, C0 283 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 2640 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-5578/5535 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 5578 cone or the 5535 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 215/283 kN ratings change with the cup." }, { "q": "What is the difference between 4T-5578/5535 and a metric ISO 355 tapered bearing?", "a": "4T-5578/5535 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×122.238×43.658 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-5578/5535 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 5578/5535 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-5578/5535 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-5578/5535 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "5578", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-5578-5535", "5578-5535", "4T-5578-5535" ], "locale_variants": {} }, { "sku": "66584-66520", "brand": "NTN", "manufacturer_designation": "NTN 4T-66584/66520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 122.238, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 149, "static_load_kN": 163, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4200, "weight_g": 1810, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-66584/66520 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-66584/66520 are separately stocked parts: a worn 66520 cup can be replaced against the existing 66584 cone, provided the new cup carries the identical reference — pairing across references changes the 33.338 mm assembled width and the rating. The 34.1 mm radial section over the 53.975 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 149/163 kN ratings belong to the assembled 66584+66520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-66584/66520 run near 3,100 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-66584/66520.", "The pure-numeric inch family at 53.975 mm bore (122.238×33.338 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 66584/66520 reference at purchase.", "ABMA makes the 53.975×122.238 mm envelope interchangeable, not the ratings: NTN prints 149/163 kN for this execution and another make of the same number can differ in roller complement.", "Never drive the 122.238 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Quote the full 66584/66520 pair at ordering: the 66584 cone also ships against sibling cups, and a cup from another reference changes the 33.338 mm assembled width and the rating.", "The 149/163 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-66584/66520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-66584/66520?", "a": "4T-66584/66520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 122.238 mm outside diameter and 33.338 mm assembled width T (4.813 × 1.313 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 149 kN, C0 163 kN, grease limiting speed 3,100 r/min, oil speed 4,200 r/min, mass about 1810 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-66584/66520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 66584 cone or the 66520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 149/163 kN ratings change with the cup." }, { "q": "What is the difference between 4T-66584/66520 and a metric ISO 355 tapered bearing?", "a": "4T-66584/66520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×122.238×33.338 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-66584/66520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 66584/66520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-66584/66520 list two speeds, 3,100 and 4,200 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-66584/66520 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "66584", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-66584-66520", "66584-66520", "4T-66584-66520" ], "locale_variants": {} }, { "sku": "557S-552A", "brand": "NTN", "manufacturer_designation": "NTN 4T-557S/552A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 123.825, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 175, "static_load_kN": 216, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4100, "weight_g": 2250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-557S/552A is the NTN 4T catalogue entry for a 53.975×123.825×38.1 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 557S sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 38.1 mm T of each 4T-557S/552A enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 175/216 kN ratings belong to the assembled 557S+552A pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 557S cone and 552A cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-557S/552A.", "The pure-numeric inch family at 53.975 mm bore (123.825×38.1 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 557S/552A reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 557S and 552A; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 53.975 mm is 2.125 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Inch and metric bores collide on paper — 53.975 mm is 2.125 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 175/216 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-557S/552A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-557S/552A?", "a": "4T-557S/552A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 123.825 mm outside diameter and 38.1 mm assembled width T (4.875 × 1.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 175 kN, C0 216 kN, grease limiting speed 3,000 r/min, oil speed 4,100 r/min, mass about 2250 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-557S/552A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 557S cone or the 552A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 175/216 kN ratings change with the cup." }, { "q": "What is the difference between 4T-557S/552A and a metric ISO 355 tapered bearing?", "a": "4T-557S/552A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×123.825×38.1 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-557S/552A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 557S/552A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-557S/552A list two speeds, 3,000 and 4,100 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-557S/552A at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "557S", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-557s-552a", "557s-552a", "557S-552A", "4T-557S-552A" ], "locale_variants": {} }, { "sku": "72212C-72487", "brand": "NTN", "manufacturer_designation": "NTN 4T-72212C/72487", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 123.825, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 171, "static_load_kN": 188, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3900, "weight_g": 2030, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-72212C/72487 at 53.975 mm bore (2.125 in), 123.825 mm cup OD and 36.512 mm assembled T, with a grease limiting speed of 2,900 r/min and an oil ceiling of 3,900 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 72212C/72487 without it. Grease relubrication at the 2,900 r/min limiting speed targets the cone-rib contact; sustaining 3,900 r/min needs an oil supply directed at the large roller ends. Cup-side note for 72487: within the pure-numeric inch family tables the 72212C cone is listed against several cup options, and it is the cup that fixes the 123.825 mm OD and the 36.512 mm assembled width — quote the full 72212C/72487 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-72212C/72487; reverse the fit logic when the cup rotates.", "applications": [ "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-72212C/72487.", "The pure-numeric inch family at 53.975 mm bore (123.825×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 72212C/72487 reference at purchase.", "An unloaded 4T-72212C/72487 near 2,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Fit selection follows the rotating ring: a rotating cone on a 53.975 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 53.975 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 171/188 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-72212C/72487; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-72212C/72487?", "a": "4T-72212C/72487 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 123.825 mm outside diameter and 36.512 mm assembled width T (4.875 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 171 kN, C0 188 kN, grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 2030 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-72212C/72487 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 72212C cone or the 72487 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 171/188 kN ratings change with the cup." }, { "q": "What is the difference between 4T-72212C/72487 and a metric ISO 355 tapered bearing?", "a": "4T-72212C/72487 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×123.825×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-72212C/72487 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 72212C/72487 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-72212C/72487 list two speeds, 2,900 and 3,900 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-72212C/72487 at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "72212C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-72212c-72487", "72212c-72487", "72212C-72487", "4T-72212C-72487" ], "locale_variants": {} }, { "sku": "HM911242-HM911210", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM911242/HM911210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 130.175, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 173, "static_load_kN": 186, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 2280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM911242/HM911210 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HM911242 identifies the cone of 53.975 mm (2.125 in) bore by catalogue lookup, and HM911210 fixes the 130.175 mm OD. Grease relubrication at the 2,700 r/min limiting speed targets the cone-rib contact; sustaining 3,600 r/min needs an oil supply directed at the large roller ends. The printed 173/186 kN ratings belong to the assembled HM911242+HM911210 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 53.975 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles", "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM911242/HM911210.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 53.975 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "ABMA makes the 53.975×130.175 mm envelope interchangeable, not the ratings: NTN prints 173/186 kN for this execution and another make of the same number can differ in roller complement.", "The 173/186 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM911242/HM911210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM911242/HM911210?", "a": "4T-HM911242/HM911210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 130.175 mm outside diameter and 36.512 mm assembled width T (5.125 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 173 kN, C0 186 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 2280 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM911242/HM911210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM911242 cone or the HM911210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 173/186 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM911242/HM911210 and a metric ISO 355 tapered bearing?", "a": "4T-HM911242/HM911210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×130.175×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM911242/HM911210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM911242/HM911210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM911242/HM911210 list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM911242/HM911210 at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM911242", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm911242-hm911210", "hm911242-hm911210", "HM911242-HM911210", "4T-HM911242-HM911210" ], "locale_variants": {} }, { "sku": "78214C-78551", "brand": "NTN", "manufacturer_designation": "NTN 4T-78214C/78551", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 53.975, "D_mm": 140.03, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 190, "static_load_kN": 212, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3400, "weight_g": 2770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-78214C/78551 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 78214C/78551 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 36.512 mm T of each 4T-78214C/78551 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-78214C/78551: press the 78551 cup square into the 140.03 mm seat first, then bring the 78214C cone (on its 53.975 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-78214C/78551 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 53.975 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-78214C/78551.", "The pure-numeric inch family at 53.975 mm bore (140.03×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 78214C/78551 reference at purchase.", "ABMA makes the 53.975×140.03 mm envelope interchangeable, not the ratings: NTN prints 190/212 kN for this execution and another make of the same number can differ in roller complement.", "Shaft and housing fillets must clear the ring chamfers of 78214C and 78551; use undercut shoulders so the rings seat on the face, not on a radius.", "ABMA makes the 53.975×140.03 mm envelope interchangeable, not the ratings: NTN prints 190/212 kN for this execution and another make of the same number can differ in roller complement.", "The 190/212 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-78214C/78551; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-78214C/78551?", "a": "4T-78214C/78551 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 53.975 mm bore (2.125 in), 140.03 mm outside diameter and 36.512 mm assembled width T (5.513 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 190 kN, C0 212 kN, grease limiting speed 2,600 r/min, oil speed 3,400 r/min, mass about 2770 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-78214C/78551 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 78214C cone or the 78551 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 190/212 kN ratings change with the cup." }, { "q": "What is the difference between 4T-78214C/78551 and a metric ISO 355 tapered bearing?", "a": "4T-78214C/78551 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 53.975×140.03×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-78214C/78551 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 78214C/78551 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-78214C/78551 list two speeds, 2,600 and 3,400 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-78214C/78551 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "78214C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-78214c-78551", "78214c-78551", "78214C-78551", "4T-78214C-78551" ], "locale_variants": {} }, { "sku": "HM807048-HM807010", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM807048/HM807010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 54.488, "D_mm": 104.775, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 189, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM807048/HM807010 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-HM807048/HM807010 are separately stocked parts: a worn HM807010 cup can be replaced against the existing HM807048 cone, provided the new cup carries the identical reference — pairing across references changes the 36.512 mm assembled width and the rating. Imperial cross-check for the drawing: 54.488×104.775×36.512 mm converts to 2.145 × 4.125 × 1.437 in; the ABMA envelope swaps with like-numbered inch parts but the 153/189 kN ratings are NTN-specific. Housing fitment sequence for 4T-HM807048/HM807010: press the HM807010 cup square into the 104.775 mm seat first, then bring the HM807048 cone (on its 54.488 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-HM807048/HM807010 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "pump and blower drive shafts with combined load", "truck and trailer axle hubs on inch-dimensioned axles", "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Hub and pinion positions of this 54.488 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-HM807048/HM807010.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 54.488 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Quote the full HM807048/HM807010 pair at ordering: the HM807048 cone also ships against sibling cups, and a cup from another reference changes the 36.512 mm assembled width and the rating.", "ABMA makes the 54.488×104.775 mm envelope interchangeable, not the ratings: NTN prints 153/189 kN for this execution and another make of the same number can differ in roller complement.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 153/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM807048/HM807010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM807048/HM807010?", "a": "4T-HM807048/HM807010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 54.488 mm bore (2.145 in), 104.775 mm outside diameter and 36.512 mm assembled width T (4.125 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 189 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1400 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM807048/HM807010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM807048 cone or the HM807010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM807048/HM807010 and a metric ISO 355 tapered bearing?", "a": "4T-HM807048/HM807010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 54.488×104.775×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM807048/HM807010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM807048/HM807010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM807048/HM807010 list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM807048/HM807010 at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM807048", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm807048-hm807010", "hm807048-hm807010", "HM807048-HM807010", "4T-HM807048-HM807010" ], "locale_variants": {} }, { "sku": "JLM506849-JLM506810", "brand": "NTN", "manufacturer_designation": "NTN 4T-JLM506849/JLM506810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 90, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86, "static_load_kN": 109, "limiting_speed_rpm": 3900, "max_rpm": 3900, "speed_oil_rpm": 5300, "weight_g": 556, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JLM506849/JLM506810 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 55×90×23 mm (assembled width T), for a shaft of about 55 mm (2.165 in). Reading the designation: 4T-JLM506849/JLM506810 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the JLM prefixed family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 55×90×23 mm converts to 2.165 × 3.543 × 0.906 in; the ABMA envelope swaps with like-numbered inch parts but the 86/109 kN ratings are NTN-specific. Cup-side note for JLM506810: within the JLM prefixed family tables the JLM506849 cone is listed against several cup options, and it is the cup that fixes the 90 mm OD and the 23 mm assembled width — quote the full JLM506849/JLM506810 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-JLM506849/JLM506810; reverse the fit logic when the cup rotates.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Hub and pinion positions of this 55 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-JLM506849/JLM506810.", "The J-prefixed JLM506849 code belongs to a metric-envelope inch family: its 55 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Quote the full JLM506849/JLM506810 pair at ordering: the JLM506849 cone also ships against sibling cups, and a cup from another reference changes the 23 mm assembled width and the rating.", "ABMA makes the 55×90 mm envelope interchangeable, not the ratings: NTN prints 86/109 kN for this execution and another make of the same number can differ in roller complement.", "Replacing one half of an adjusted pair without resetting end play negates the 23 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 86/109 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JLM506849/JLM506810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JLM506849/JLM506810?", "a": "4T-JLM506849/JLM506810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 55 mm bore (2.165 in), 90 mm outside diameter and 23 mm assembled width T (3.543 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86 kN, C0 109 kN, grease limiting speed 3,900 r/min, oil speed 5,300 r/min, mass about 556 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JLM506849/JLM506810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JLM506849 cone or the JLM506810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86/109 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JLM506849/JLM506810 and a metric ISO 355 tapered bearing?", "a": "4T-JLM506849/JLM506810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 55×90×23 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JLM506849/JLM506810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JLM506849/JLM506810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JLM506849/JLM506810 list two speeds, 3,900 and 5,300 r/min?", "a": "The lower figure, 3,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JLM506849/JLM506810 at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JLM506849", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=184", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jlm506849-jlm506810", "4t-jlm506849-jlm506810", "jlm506849-jlm506810", "JLM506849-JLM506810", "4T-JLM506849-JLM506810" ], "locale_variants": {} }, { "sku": "JM207049-JM207010", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM207049/JM207010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 95, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 119, "static_load_kN": 144, "limiting_speed_rpm": 3800, "max_rpm": 3800, "speed_oil_rpm": 5100, "weight_g": 823, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.165 in (55 mm) shaft position as 4T-JM207049/JM207010: cone JM207049, cup JM207010, profiled rollers and a pressed-steel cage, rated 119 kN basic dynamic and 144 kN static. Cone and cup of 4T-JM207049/JM207010 are separately stocked parts: a worn JM207010 cup can be replaced against the existing JM207049 cone, provided the new cup carries the identical reference — pairing across references changes the 29 mm assembled width and the rating. The 20.0 mm radial section over the 55 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 119/144 kN ratings belong to the assembled JM207049+JM207010 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-JM207049/JM207010, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Hub and pinion positions of this 55 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-JM207049/JM207010.", "The J-prefixed JM207049 code belongs to a metric-envelope inch family: its 55 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "An unloaded 4T-JM207049/JM207010 near 3,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of JM207049 and JM207010; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full JM207049/JM207010 pair at ordering: the JM207049 cone also ships against sibling cups, and a cup from another reference changes the 29 mm assembled width and the rating.", "The 119/144 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM207049/JM207010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM207049/JM207010?", "a": "4T-JM207049/JM207010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 55 mm bore (2.165 in), 95 mm outside diameter and 29 mm assembled width T (3.74 × 1.142 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 119 kN, C0 144 kN, grease limiting speed 3,800 r/min, oil speed 5,100 r/min, mass about 823 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM207049/JM207010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM207049 cone or the JM207010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 119/144 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM207049/JM207010 and a metric ISO 355 tapered bearing?", "a": "4T-JM207049/JM207010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 55×95×29 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM207049/JM207010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM207049/JM207010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM207049/JM207010 list two speeds, 3,800 and 5,100 r/min?", "a": "The lower figure, 3,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM207049/JM207010 at 5,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM207049", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm207049-jm207010", "4t-jm207049-jm207010", "jm207049-jm207010", "JM207049-JM207010", "4T-JM207049-JM207010" ], "locale_variants": {} }, { "sku": "385-382A", "brand": "NTN", "manufacturer_designation": "NTN 4T-385/382A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 96.838, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 96.5, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 615, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-385/382A denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 385 and cup 382A delivered as a matched, separable pair of 55 mm bore and 96.838 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 385/382A without it. Grease relubrication at the 3,700 r/min limiting speed targets the cone-rib contact; sustaining 5,000 r/min needs an oil supply directed at the large roller ends. Cup-side note for 382A: within the pure-numeric inch family tables the 385 cone is listed against several cup options, and it is the cup that fixes the 96.838 mm OD and the 21 mm assembled width — quote the full 385/382A pair, never the cone alone. Mount the 55 mm cone with an induction heater (max 120 °C) and press the 96.838 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys", "machine-tool headstocks on inch spindles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Hub and pinion positions of this 55 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-385/382A.", "The pure-numeric inch family at 55 mm bore (96.838×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 385/382A reference at purchase.", "Open 4T-385/382A sets have no seals: a hub or gearbox needs external sealing or the 3,700 r/min grease figure is meaningless once water reaches the cone rib.", "Quote the full 385/382A pair at ordering: the 385 cone also ships against sibling cups, and a cup from another reference changes the 21 mm assembled width and the rating.", "Grease packs must leave free volume inside the 21 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,000 r/min raises temperature and destroys the setting.", "The 86.5/96.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-385/382A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-385/382A?", "a": "4T-385/382A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 55 mm bore (2.165 in), 96.838 mm outside diameter and 21 mm assembled width T (3.813 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 96.5 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 615 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-385/382A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 385 cone or the 382A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/96.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-385/382A and a metric ISO 355 tapered bearing?", "a": "4T-385/382A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 55×96.838×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-385/382A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 385/382A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-385/382A list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-385/382A at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "385", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "385-382a", "4t-385-382a", "385-382A", "4T-385-382A" ], "locale_variants": {} }, { "sku": "JH307749-JH307710", "brand": "NTN", "manufacturer_designation": "NTN 4T-JH307749/JH307710", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 110, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 192, "static_load_kN": 219, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4600, "weight_g": 1700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-JH307749/JH307710 at 55 mm bore (2.165 in), 110 mm cup OD and 39 mm assembled T, with a grease limiting speed of 3,500 r/min and an oil ceiling of 4,600 r/min. Cone and cup of 4T-JH307749/JH307710 are separately stocked parts: a worn JH307710 cup can be replaced against the existing JH307749 cone, provided the new cup carries the identical reference — pairing across references changes the 39 mm assembled width and the rating. Contact-angle geometry of the JH heavy metric-envelope family gives 4T-JH307749/JH307710 its radial/axial load split — at 192/219 kN the static rating is about 1.14× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-JH307749/JH307710: press the JH307710 cup square into the 110 mm seat first, then bring the JH307749 cone (on its 55 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-JH307749/JH307710 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "agricultural tractor transmission and PTO shafts", "industrial gearboxes built to inch shafting", "construction-equipment pivot and wheel positions", "mining and quarry conveyor drive pulleys" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Hub and pinion positions of this 55 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-JH307749/JH307710.", "The J-prefixed JH307749 code belongs to a metric-envelope inch family: its 55 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "ABMA makes the 55×110 mm envelope interchangeable, not the ratings: NTN prints 192/219 kN for this execution and another make of the same number can differ in roller complement.", "Replacing one half of an adjusted pair without resetting end play negates the 39 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "An unloaded 4T-JH307749/JH307710 near 3,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 192/219 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JH307749/JH307710; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JH307749/JH307710?", "a": "4T-JH307749/JH307710 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 55 mm bore (2.165 in), 110 mm outside diameter and 39 mm assembled width T (4.331 × 1.535 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 192 kN, C0 219 kN, grease limiting speed 3,500 r/min, oil speed 4,600 r/min, mass about 1700 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JH307749/JH307710 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JH307749 cone or the JH307710 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 192/219 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JH307749/JH307710 and a metric ISO 355 tapered bearing?", "a": "4T-JH307749/JH307710 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 55×110×39 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JH307749/JH307710 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JH307749/JH307710 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JH307749/JH307710 list two speeds, 3,500 and 4,600 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JH307749/JH307710 at 4,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JH307749", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jh307749-jh307710", "4t-jh307749-jh307710", "jh307749-jh307710", "JH307749-JH307710", "4T-JH307749-JH307710" ], "locale_variants": {} }, { "sku": "28680-28622", "brand": "NTN", "manufacturer_designation": "NTN 4T-28680/28622", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 55.562, "D_mm": 97.63, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 98, "static_load_kN": 128, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 776, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-28680/28622 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 55.562×97.63×24.608 mm (assembled width T), for a shaft of about 55.562 mm (2.187 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 28680 identifies the cone of 55.562 mm (2.187 in) bore by catalogue lookup, and 28622 fixes the 97.63 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 24.608 mm T of each 4T-28680/28622 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 98/128 kN ratings belong to the assembled 28680+28622 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-28680/28622, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 55.562 mm cone by induction heating (max 120 °C) and the 97.63 mm cup with a press sleeve; at 776 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 55.562 mm bore (97.63×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28680/28622 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 55.562 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 24.608 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,900 r/min raises temperature and destroys the setting.", "Grease packs must leave free volume inside the 24.608 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,900 r/min raises temperature and destroys the setting.", "The 98/128 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28680/28622; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28680/28622?", "a": "4T-28680/28622 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 55.562 mm bore (2.187 in), 97.63 mm outside diameter and 24.608 mm assembled width T (3.844 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 98 kN, C0 128 kN, grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 776 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28680/28622 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28680 cone or the 28622 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 98/128 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28680/28622 and a metric ISO 355 tapered bearing?", "a": "4T-28680/28622 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 55.562×97.63×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28680/28622 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28680/28622 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28680/28622 list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28680/28622 at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28680", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28680-28622", "28680-28622", "4T-28680-28622" ], "locale_variants": {} }, { "sku": "72218C-72487", "brand": "NTN", "manufacturer_designation": "NTN 4T-72218C/72487", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 55.562, "D_mm": 123.825, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 171, "static_load_kN": 188, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3900, "weight_g": 2000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.187 in (55.562 mm) shaft position as 4T-72218C/72487: cone 72218C, cup 72487, profiled rollers and a pressed-steel cage, rated 171 kN basic dynamic and 188 kN static. Cone and cup of 4T-72218C/72487 are separately stocked parts: a worn 72487 cup can be replaced against the existing 72218C cone, provided the new cup carries the identical reference — pairing across references changes the 36.512 mm assembled width and the rating. Grease relubrication at the 2,900 r/min limiting speed targets the cone-rib contact; sustaining 3,900 r/min needs an oil supply directed at the large roller ends. Cup-side note for 72487: within the pure-numeric inch family tables the 72218C cone is listed against several cup options, and it is the cup that fixes the 123.825 mm OD and the 36.512 mm assembled width — quote the full 72218C/72487 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-72218C/72487; reverse the fit logic when the cup rotates.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 55.562 mm cone by induction heating (max 120 °C) and the 123.825 mm cup with a press sleeve; at 2000 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 55.562 mm bore (123.825×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 72218C/72487 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 36.512 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "An unloaded 4T-72218C/72487 near 2,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 55.562 mm is 2.187 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 171/188 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-72218C/72487; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-72218C/72487?", "a": "4T-72218C/72487 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 55.562 mm bore (2.187 in), 123.825 mm outside diameter and 36.512 mm assembled width T (4.875 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 171 kN, C0 188 kN, grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 2000 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-72218C/72487 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 72218C cone or the 72487 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 171/188 kN ratings change with the cup." }, { "q": "What is the difference between 4T-72218C/72487 and a metric ISO 355 tapered bearing?", "a": "4T-72218C/72487 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 55.562×123.825×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-72218C/72487 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 72218C/72487 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-72218C/72487 list two speeds, 2,900 and 3,900 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-72218C/72487 at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "72218C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-72218c-72487", "72218c-72487", "72218C-72487", "4T-72218C-72487" ], "locale_variants": {} }, { "sku": "HM813840-HM813810", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM813840/HM813810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 55.562, "D_mm": 127, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 181, "static_load_kN": 228, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 2340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-HM813840/HM813810 at 55.562 mm bore (2.187 in), 127 mm cup OD and 36.512 mm assembled T, with a grease limiting speed of 2,900 r/min and an oil ceiling of 3,800 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HM813840 identifies the cone of 55.562 mm (2.187 in) bore by catalogue lookup, and HM813810 fixes the 127 mm OD. Imperial cross-check for the drawing: 55.562×127×36.512 mm converts to 2.187 × 5 × 1.437 in; the ABMA envelope swaps with like-numbered inch parts but the 181/228 kN ratings are NTN-specific. The printed 181/228 kN ratings belong to the assembled HM813840+HM813810 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-HM813840/HM813810, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 55.562 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 2340 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 55.562 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "ABMA makes the 55.562×127 mm envelope interchangeable, not the ratings: NTN prints 181/228 kN for this execution and another make of the same number can differ in roller complement.", "Fit selection follows the rotating ring: a rotating cone on a 55.562 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Open 4T-HM813840/HM813810 sets have no seals: a hub or gearbox needs external sealing or the 2,900 r/min grease figure is meaningless once water reaches the cone rib.", "The 181/228 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM813840/HM813810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM813840/HM813810?", "a": "4T-HM813840/HM813810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 55.562 mm bore (2.187 in), 127 mm outside diameter and 36.512 mm assembled width T (5 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 228 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 2340 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM813840/HM813810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM813840 cone or the HM813810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 181/228 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM813840/HM813810 and a metric ISO 355 tapered bearing?", "a": "4T-HM813840/HM813810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 55.562×127×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM813840/HM813810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM813840/HM813810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM813840/HM813810 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM813840/HM813810 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM813840", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm813840-hm813810", "hm813840-hm813810", "HM813840-HM813810", "4T-HM813840-HM813810" ], "locale_variants": {} }, { "sku": "389-382A", "brand": "NTN", "manufacturer_designation": "NTN 4T-389/382A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 55.575, "D_mm": 96.838, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 96.5, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 606, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-389/382A belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 389/382A without it. The 20.6 mm radial section over the 55.575 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-389/382A: press the 382A cup square into the 96.838 mm seat first, then bring the 389 cone (on its 55.575 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-389/382A is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 55.575 mm cone by induction heating (max 120 °C) and the 96.838 mm cup with a press sleeve; at 606 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 55.575 mm bore (96.838×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 389/382A reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 21 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "An unloaded 4T-389/382A near 3,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 21 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 86.5/96.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-389/382A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-389/382A?", "a": "4T-389/382A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 55.575 mm bore (2.188 in), 96.838 mm outside diameter and 21 mm assembled width T (3.813 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 96.5 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 606 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-389/382A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 389 cone or the 382A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/96.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-389/382A and a metric ISO 355 tapered bearing?", "a": "4T-389/382A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 55.575×96.838×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-389/382A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 389/382A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-389/382A list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-389/382A at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "389", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "389-382a", "4t-389-382a", "389-382A", "4T-389-382A" ], "locale_variants": {} }, { "sku": "387-382A-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-387/382A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 96.838, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 96.5, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 582, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.25 in (57.15 mm) shaft position as 4T-387/382A: cone 387, cup 382A, profiled rollers and a pressed-steel cage, rated 86.5 kN basic dynamic and 96.5 kN static. Cone and cup of 4T-387/382A are separately stocked parts: a worn 382A cup can be replaced against the existing 387 cone, provided the new cup carries the identical reference — pairing across references changes the 21 mm assembled width and the rating. Catalogue mass of the 4T-387/382A cone-plus-cup set is 582 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 382A: within the pure-numeric inch family tables the 387 cone is listed against several cup options, and it is the cup that fixes the 96.838 mm OD and the 21 mm assembled width — quote the full 387/382A pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-387/382A, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 96.838 mm cup with a press sleeve; at 582 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (96.838×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 387/382A reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 21 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 57.15 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Open 4T-387/382A sets have no seals: a hub or gearbox needs external sealing or the 3,700 r/min grease figure is meaningless once water reaches the cone rib.", "The 86.5/96.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-387/382A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-387/382A?", "a": "4T-387/382A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 96.838 mm outside diameter and 21 mm assembled width T (3.813 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 96.5 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 582 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-387/382A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 387 cone or the 382A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/96.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-387/382A and a metric ISO 355 tapered bearing?", "a": "4T-387/382A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×96.838×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-387/382A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 387/382A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-387/382A list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-387/382A at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "387-382", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "387-382A", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "387-382a", "4t-387-382a", "387-382A", "4T-387-382A", "387-382A-NTN" ], "locale_variants": {} }, { "sku": "387A-382A", "brand": "NTN", "manufacturer_designation": "NTN 4T-387A/382A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 96.838, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 96.5, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 580, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-387A/382A belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 387A identifies the cone of 57.15 mm (2.25 in) bore by catalogue lookup, and 382A fixes the 96.838 mm OD. Speed planning uses both catalogue columns: grease 3,700 r/min is the mechanical ceiling for 4T-387A/382A, oil 5,000 r/min with circulating oil — a 1,300 r/min margin at this size. The printed 86.5/96.5 kN ratings belong to the assembled 387A+382A pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-387A/382A is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 96.838 mm cup with a press sleeve; at 580 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (96.838×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 387A/382A reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 21 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 57.15 mm is 2.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 57.15 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 86.5/96.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-387A/382A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-387A/382A?", "a": "4T-387A/382A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 96.838 mm outside diameter and 21 mm assembled width T (3.813 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 96.5 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 580 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-387A/382A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 387A cone or the 382A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/96.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-387A/382A and a metric ISO 355 tapered bearing?", "a": "4T-387A/382A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×96.838×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-387A/382A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 387A/382A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-387A/382A list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-387A/382A at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "387A-382S", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "387a-382a", "4t-387a-382a", "387A-382A", "4T-387A-382A" ], "locale_variants": {} }, { "sku": "387AS-382A", "brand": "NTN", "manufacturer_designation": "NTN 4T-387AS/382A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 96.838, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 96.5, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 575, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-387AS/382A is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 57.15×96.838×21 mm (assembled width T), for a shaft of about 57.15 mm (2.25 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 387AS/382A without it. Speed planning uses both catalogue columns: grease 3,700 r/min is the mechanical ceiling for 4T-387AS/382A, oil 5,000 r/min with circulating oil — a 1,300 r/min margin at this size. The printed 86.5/96.5 kN ratings belong to the assembled 387AS+382A pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 57.15 mm cone with an induction heater (max 120 °C) and press the 96.838 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 96.838 mm cup with a press sleeve; at 575 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (96.838×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 387AS/382A reference at purchase.", "Do not confuse T (21 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Quote the full 387AS/382A pair at ordering: the 387AS cone also ships against sibling cups, and a cup from another reference changes the 21 mm assembled width and the rating.", "Grease packs must leave free volume inside the 21 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,000 r/min raises temperature and destroys the setting.", "The 86.5/96.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-387AS/382A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-387AS/382A?", "a": "4T-387AS/382A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 96.838 mm outside diameter and 21 mm assembled width T (3.813 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 96.5 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 575 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-387AS/382A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 387AS cone or the 382A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/96.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-387AS/382A and a metric ISO 355 tapered bearing?", "a": "4T-387AS/382A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×96.838×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-387AS/382A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 387AS/382A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-387AS/382A list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-387AS/382A at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "387AS", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "387as-382a", "4t-387as-382a", "387AS-382A", "4T-387AS-382A" ], "locale_variants": {} }, { "sku": "387S-382A", "brand": "NTN", "manufacturer_designation": "NTN 4T-387S/382A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 96.838, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 96.5, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 584, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-387S/382A denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 387S and cup 382A delivered as a matched, separable pair of 57.15 mm bore and 96.838 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 387S identifies the cone of 57.15 mm (2.25 in) bore by catalogue lookup, and 382A fixes the 96.838 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 21 mm T of each 4T-387S/382A enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-387S/382A: press the 382A cup square into the 96.838 mm seat first, then bring the 387S cone (on its 57.15 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 57.15 mm cone with an induction heater (max 120 °C) and press the 96.838 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 96.838 mm cup with a press sleeve; at 584 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (96.838×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 387S/382A reference at purchase.", "Open 4T-387S/382A sets have no seals: a hub or gearbox needs external sealing or the 3,700 r/min grease figure is meaningless once water reaches the cone rib.", "An unloaded 4T-387S/382A near 3,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "An unloaded 4T-387S/382A near 3,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 86.5/96.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-387S/382A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-387S/382A?", "a": "4T-387S/382A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 96.838 mm outside diameter and 21 mm assembled width T (3.813 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 96.5 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 584 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-387S/382A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 387S cone or the 382A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/96.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-387S/382A and a metric ISO 355 tapered bearing?", "a": "4T-387S/382A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×96.838×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-387S/382A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 387S/382A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-387S/382A list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-387S/382A at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "387S", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "387s-382a", "4t-387s-382a", "387S-382A", "4T-387S-382A" ], "locale_variants": {} }, { "sku": "28682-28622", "brand": "NTN", "manufacturer_designation": "NTN 4T-28682/28622", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 97.63, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 98, "static_load_kN": 128, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 749, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-28682/28622 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 57.15×97.63×24.608 mm (assembled width T), for a shaft of about 57.15 mm (2.25 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 28682 sits in the pure-numeric inch family. The 20.2 mm radial section over the 57.15 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 28622: within the pure-numeric inch family tables the 28682 cone is listed against several cup options, and it is the cup that fixes the 97.63 mm OD and the 24.608 mm assembled width — quote the full 28682/28622 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 57.15 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 97.63 mm cup with a press sleeve; at 749 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (97.63×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28682/28622 reference at purchase.", "Quote the full 28682/28622 pair at ordering: the 28682 cone also ships against sibling cups, and a cup from another reference changes the 24.608 mm assembled width and the rating.", "Quote the full 28682/28622 pair at ordering: the 28682 cone also ships against sibling cups, and a cup from another reference changes the 24.608 mm assembled width and the rating.", "Do not confuse T (24.608 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 98/128 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28682/28622; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28682/28622?", "a": "4T-28682/28622 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 97.63 mm outside diameter and 24.608 mm assembled width T (3.844 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 98 kN, C0 128 kN, grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 749 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28682/28622 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28682 cone or the 28622 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 98/128 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28682/28622 and a metric ISO 355 tapered bearing?", "a": "4T-28682/28622 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×97.63×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28682/28622 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28682/28622 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28682/28622 list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28682/28622 at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28682", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28682-28622", "28682-28622", "4T-28682-28622" ], "locale_variants": {} }, { "sku": "45289-45220", "brand": "NTN", "manufacturer_designation": "NTN 4T-45289/45220", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 104.775, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 144, "static_load_kN": 169, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 57.15 mm carrying combined radial and thrust load, NTN lists 4T-45289/45220, a single-row 4T tapered roller set of 144 kN C and 169 kN C0 inside the 104.775 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 45289 sits in the pure-numeric inch family. The 23.8 mm radial section over the 57.15 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 144/169 kN ratings belong to the assembled 45289+45220 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-45289/45220 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 104.775 mm cup with a press sleeve; at 1100 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (104.775×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 45289/45220 reference at purchase.", "Open 4T-45289/45220 sets have no seals: a hub or gearbox needs external sealing or the 3,500 r/min grease figure is meaningless once water reaches the cone rib.", "Never drive the 104.775 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 57.15×104.775 mm envelope interchangeable, not the ratings: NTN prints 144/169 kN for this execution and another make of the same number can differ in roller complement.", "The 144/169 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-45289/45220; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-45289/45220?", "a": "4T-45289/45220 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 104.775 mm outside diameter and 30.162 mm assembled width T (4.125 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 144 kN, C0 169 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1100 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-45289/45220 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 45289 cone or the 45220 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 144/169 kN ratings change with the cup." }, { "q": "What is the difference between 4T-45289/45220 and a metric ISO 355 tapered bearing?", "a": "4T-45289/45220 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×104.775×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-45289/45220 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 45289/45220 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-45289/45220 list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-45289/45220 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "45289", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-45289-45220", "45289-45220", "4T-45289-45220" ], "locale_variants": {} }, { "sku": "462-453X-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-462/453X", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 104.775, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 127, "static_load_kN": 148, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1060, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-462/453X denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 462 and cup 453X delivered as a matched, separable pair of 57.15 mm bore and 104.775 mm outside diameter. Cone and cup of 4T-462/453X are separately stocked parts: a worn 453X cup can be replaced against the existing 462 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Grease relubrication at the 3,500 r/min limiting speed targets the cone-rib contact; sustaining 4,700 r/min needs an oil supply directed at the large roller ends. The printed 127/148 kN ratings belong to the assembled 462+453X pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 57.15 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 104.775 mm cup with a press sleeve; at 1060 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (104.775×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 462/453X reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 57.15 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 57.15×104.775 mm envelope interchangeable, not the ratings: NTN prints 127/148 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 57.15×104.775 mm envelope interchangeable, not the ratings: NTN prints 127/148 kN for this execution and another make of the same number can differ in roller complement.", "The 127/148 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-462/453X; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-462/453X?", "a": "4T-462/453X is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 104.775 mm outside diameter and 30.162 mm assembled width T (4.125 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 127 kN, C0 148 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1060 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-462/453X interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 462 cone or the 453X cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 127/148 kN ratings change with the cup." }, { "q": "What is the difference between 4T-462/453X and a metric ISO 355 tapered bearing?", "a": "4T-462/453X follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×104.775×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-462/453X mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 462/453X references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-462/453X list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-462/453X at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "462-453X", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "462-453x", "4t-462-453x", "462-453X", "4T-462-453X", "462-453X-NTN" ], "locale_variants": {} }, { "sku": "469-453X", "brand": "NTN", "manufacturer_designation": "NTN 4T-469/453X", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 104.775, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 127, "static_load_kN": 148, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1060, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-469/453X is the NTN 4T catalogue entry for a 57.15×104.775×30.162 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 469 sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-469/453X enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 453X: within the pure-numeric inch family tables the 469 cone is listed against several cup options, and it is the cup that fixes the 104.775 mm OD and the 30.162 mm assembled width — quote the full 469/453X pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 57.15 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 104.775 mm cup with a press sleeve; at 1060 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (104.775×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 469/453X reference at purchase.", "Open 4T-469/453X sets have no seals: a hub or gearbox needs external sealing or the 3,500 r/min grease figure is meaningless once water reaches the cone rib.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,700 r/min raises temperature and destroys the setting.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 127/148 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-469/453X; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-469/453X?", "a": "4T-469/453X is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 104.775 mm outside diameter and 30.162 mm assembled width T (4.125 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 127 kN, C0 148 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1060 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-469/453X interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 469 cone or the 453X cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 127/148 kN ratings change with the cup." }, { "q": "What is the difference between 4T-469/453X and a metric ISO 355 tapered bearing?", "a": "4T-469/453X follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×104.775×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-469/453X mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 469/453X references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-469/453X list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-469/453X at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "469-453A", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-469 paired with a different cup (453A): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "469-454", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-469 paired with a different cup (454): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "469-453x", "4t-469-453x", "469-453X", "4T-469-453X" ], "locale_variants": {} }, { "sku": "469-453A", "brand": "NTN", "manufacturer_designation": "NTN 4T-469/453A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 107.95, "B_mm": 27.783, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 127, "static_load_kN": 148, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-469/453A denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 469 and cup 453A delivered as a matched, separable pair of 57.15 mm bore and 107.95 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 469 identifies the cone of 57.15 mm (2.25 in) bore by catalogue lookup, and 453A fixes the 107.95 mm OD. Selection: C 127 kN against C0 148 kN gives a C0/C ratio of 1.17 for the 57.15 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 453A: within the pure-numeric inch family tables the 469 cone is listed against several cup options, and it is the cup that fixes the 107.95 mm OD and the 27.783 mm assembled width — quote the full 469/453A pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-469/453A is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 107.95 mm cup with a press sleeve; at 1110 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (107.95×27.783 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 469/453A reference at purchase.", "Inch and metric bores collide on paper — 57.15 mm is 2.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "An unloaded 4T-469/453A near 3,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Fit selection follows the rotating ring: a rotating cone on a 57.15 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 127/148 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-469/453A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-469/453A?", "a": "4T-469/453A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 107.95 mm outside diameter and 27.783 mm assembled width T (4.25 × 1.094 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 127 kN, C0 148 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1110 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-469/453A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 469 cone or the 453A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 127/148 kN ratings change with the cup." }, { "q": "What is the difference between 4T-469/453A and a metric ISO 355 tapered bearing?", "a": "4T-469/453A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×107.95×27.783 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-469/453A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 469/453A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-469/453A list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-469/453A at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "469-453X", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-469 paired with a different cup (453X): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "469-454", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-469 paired with a different cup (454): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "469-453a", "4t-469-453a", "469-453A", "4T-469-453A" ], "locale_variants": {} }, { "sku": "390-394A", "brand": "NTN", "manufacturer_designation": "NTN 4T-390/394A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 110, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 99.5, "static_load_kN": 120, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 961, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-390/394A is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 57.15×110×22 mm (assembled width T), for a shaft of about 57.15 mm (2.25 in). Reading the designation: 4T-390/394A follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 1.7 kN of dynamic capacity per millimetre of bore summarises the 99.5 kN rating over the 57.15 mm bore — sanity-check any interchange candidate against this ratio and the 22 mm T. Housing fitment sequence for 4T-390/394A: press the 394A cup square into the 110 mm seat first, then bring the 390 cone (on its 57.15 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-390/394A sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 110 mm cup with a press sleeve; at 961 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (110×22 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 390/394A reference at purchase.", "Do not confuse T (22 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 57.15 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "An unloaded 4T-390/394A near 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 99.5/120 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-390/394A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-390/394A?", "a": "4T-390/394A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 110 mm outside diameter and 22 mm assembled width T (4.331 × 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 99.5 kN, C0 120 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 961 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-390/394A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 390 cone or the 394A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 99.5/120 kN ratings change with the cup." }, { "q": "What is the difference between 4T-390/394A and a metric ISO 355 tapered bearing?", "a": "4T-390/394A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×110×22 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-390/394A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 390/394A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-390/394A list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-390/394A at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "390", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "390-394a", "4t-390-394a", "390-394A", "4T-390-394A" ], "locale_variants": {} }, { "sku": "469-454", "brand": "NTN", "manufacturer_designation": "NTN 4T-469/454", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 110, "B_mm": 27.795, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 127, "static_load_kN": 148, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 1240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-469/454 at 57.15 mm bore (2.25 in), 110 mm cup OD and 27.795 mm assembled T, with a grease limiting speed of 3,500 r/min and an oil ceiling of 4,700 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 469/454 without it. Grease relubrication at the 3,500 r/min limiting speed targets the cone-rib contact; sustaining 4,700 r/min needs an oil supply directed at the large roller ends. Cup-side note for 454: within the pure-numeric inch family tables the 469 cone is listed against several cup options, and it is the cup that fixes the 110 mm OD and the 27.795 mm assembled width — quote the full 469/454 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-469/454; reverse the fit logic when the cup rotates.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 110 mm cup with a press sleeve; at 1240 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (110×27.795 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 469/454 reference at purchase.", "An unloaded 4T-469/454 near 3,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Fit selection follows the rotating ring: a rotating cone on a 57.15 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 57.15 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 127/148 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-469/454; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-469/454?", "a": "4T-469/454 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 110 mm outside diameter and 27.795 mm assembled width T (4.331 × 1.094 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 127 kN, C0 148 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1240 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-469/454 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 469 cone or the 454 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 127/148 kN ratings change with the cup." }, { "q": "What is the difference between 4T-469/454 and a metric ISO 355 tapered bearing?", "a": "4T-469/454 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×110×27.795 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-469/454 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 469/454 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-469/454 list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-469/454 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "469-453X", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-469 paired with a different cup (453X): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." }, { "equiv_sku": "469-453A", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-469 paired with a different cup (453A): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-469-454", "469-454", "4T-469-454" ], "locale_variants": {} }, { "sku": "39580-39520-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-39580/39520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 195, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-39580/39520 at 57.15 mm bore (2.25 in), 112.712 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 3,200 r/min and an oil ceiling of 4,200 r/min. Reading the designation: 4T-39580/39520 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 3,200 r/min limiting speed targets the cone-rib contact; sustaining 4,200 r/min needs an oil supply directed at the large roller ends. The printed 153/195 kN ratings belong to the assembled 39580+39520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 57.15 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 1410 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 39580/39520 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-39580/39520 sets have no seals: a hub or gearbox needs external sealing or the 3,200 r/min grease figure is meaningless once water reaches the cone rib.", "Never drive the 112.712 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 153/195 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-39580/39520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-39580/39520?", "a": "4T-39580/39520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 195 kN, grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1410 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-39580/39520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 39580 cone or the 39520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/195 kN ratings change with the cup." }, { "q": "What is the difference between 4T-39580/39520 and a metric ISO 355 tapered bearing?", "a": "4T-39580/39520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-39580/39520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 39580/39520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-39580/39520 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-39580/39520 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "39580-39520", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "39580-39528", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-39580-39520", "39580-39520", "4T-39580-39520", "39580-39520-NTN" ], "locale_variants": {} }, { "sku": "39581-39520-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-39581/39520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 195, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-39581/39520 at 57.15 mm bore (2.25 in), 112.712 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 3,200 r/min and an oil ceiling of 4,200 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 39581 sits in the pure-numeric inch family. The 2.7 kN of dynamic capacity per millimetre of bore summarises the 153 kN rating over the 57.15 mm bore — sanity-check any interchange candidate against this ratio and the 30.162 mm T. Housing fitment sequence for 4T-39581/39520: press the 39520 cup square into the 112.712 mm seat first, then bring the 39581 cone (on its 57.15 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-39581/39520, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 1400 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 39581/39520 reference at purchase.", "ABMA makes the 57.15×112.712 mm envelope interchangeable, not the ratings: NTN prints 153/195 kN for this execution and another make of the same number can differ in roller complement.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,200 r/min raises temperature and destroys the setting.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,200 r/min raises temperature and destroys the setting.", "The 153/195 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-39581/39520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-39581/39520?", "a": "4T-39581/39520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 195 kN, grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1400 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-39581/39520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 39581 cone or the 39520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/195 kN ratings change with the cup." }, { "q": "What is the difference between 4T-39581/39520 and a metric ISO 355 tapered bearing?", "a": "4T-39581/39520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-39581/39520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 39581/39520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-39581/39520 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-39581/39520 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "39581-39520", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "39581-39528", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-39581-39520", "39581-39520", "4T-39581-39520", "39581-39520-NTN" ], "locale_variants": {} }, { "sku": "3979-3920", "brand": "NTN", "manufacturer_designation": "NTN 4T-3979/3920", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 132, "static_load_kN": 174, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 1410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3979/3920 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-3979/3920 are separately stocked parts: a worn 3920 cup can be replaced against the existing 3979 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Imperial cross-check for the drawing: 57.15×112.712×30.162 mm converts to 2.25 × 4.437 × 1.187 in; the ABMA envelope swaps with like-numbered inch parts but the 132/174 kN ratings are NTN-specific. The printed 132/174 kN ratings belong to the assembled 3979+3920 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 57.15 mm cone with an induction heater (max 120 °C) and press the 112.712 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 1410 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3979/3920 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 57.15 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Never drive the 112.712 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 4T-3979/3920 sets have no seals: a hub or gearbox needs external sealing or the 3,200 r/min grease figure is meaningless once water reaches the cone rib.", "The 132/174 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3979/3920; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3979/3920?", "a": "4T-3979/3920 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 132 kN, C0 174 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 1410 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3979/3920 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3979 cone or the 3920 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 132/174 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3979/3920 and a metric ISO 355 tapered bearing?", "a": "4T-3979/3920 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3979/3920 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3979/3920 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3979/3920 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3979/3920 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3979", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3979-3920", "3979-3920", "4T-3979-3920" ], "locale_variants": {} }, { "sku": "33225-33462", "brand": "NTN", "manufacturer_designation": "NTN 4T-33225/33462", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 117.475, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 129, "static_load_kN": 175, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1580, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-33225/33462 at 57.15 mm bore (2.25 in), 117.475 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 3,000 r/min and an oil ceiling of 4,000 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 33225 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 3,000 r/min is the mechanical ceiling for 4T-33225/33462, oil 4,000 r/min with circulating oil — a 1,000 r/min margin at this size. The printed 129/175 kN ratings belong to the assembled 33225+33462 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-33225/33462, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 117.475 mm cup with a press sleeve; at 1580 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (117.475×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 33225/33462 reference at purchase.", "Inch and metric bores collide on paper — 57.15 mm is 2.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,000 r/min raises temperature and destroys the setting.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,000 r/min raises temperature and destroys the setting.", "The 129/175 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-33225/33462; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-33225/33462?", "a": "4T-33225/33462 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 117.475 mm outside diameter and 30.162 mm assembled width T (4.625 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 129 kN, C0 175 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1580 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-33225/33462 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 33225 cone or the 33462 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 129/175 kN ratings change with the cup." }, { "q": "What is the difference between 4T-33225/33462 and a metric ISO 355 tapered bearing?", "a": "4T-33225/33462 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×117.475×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-33225/33462 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 33225/33462 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-33225/33462 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-33225/33462 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "33225", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-33225-33462", "33225-33462", "4T-33225-33462" ], "locale_variants": {} }, { "sku": "66225-66462", "brand": "NTN", "manufacturer_designation": "NTN 4T-66225/66462", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 117.475, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 144, "static_load_kN": 153, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4400, "weight_g": 1540, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-66225/66462 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 66225 and cup 66462 delivered as a matched, separable pair of 57.15 mm bore and 117.475 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 66225 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 3,300 r/min is the mechanical ceiling for 4T-66225/66462, oil 4,400 r/min with circulating oil — a 1,100 r/min margin at this size. Cup-side note for 66462: within the pure-numeric inch family tables the 66225 cone is listed against several cup options, and it is the cup that fixes the 117.475 mm OD and the 33.338 mm assembled width — quote the full 66225/66462 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 57.15 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 117.475 mm cup with a press sleeve; at 1540 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (117.475×33.338 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 66225/66462 reference at purchase.", "Grease packs must leave free volume inside the 33.338 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,400 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 57.15 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of 66225 and 66462; use undercut shoulders so the rings seat on the face, not on a radius.", "The 144/153 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-66225/66462; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-66225/66462?", "a": "4T-66225/66462 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 117.475 mm outside diameter and 33.338 mm assembled width T (4.625 × 1.313 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 144 kN, C0 153 kN, grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 1540 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-66225/66462 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 66225 cone or the 66462 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 144/153 kN ratings change with the cup." }, { "q": "What is the difference between 4T-66225/66462 and a metric ISO 355 tapered bearing?", "a": "4T-66225/66462 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×117.475×33.338 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-66225/66462 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 66225/66462 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-66225/66462 list two speeds, 3,300 and 4,400 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-66225/66462 at 4,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "66225", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-66225-66462", "66225-66462", "4T-66225-66462" ], "locale_variants": {} }, { "sku": "623-612", "brand": "NTN", "manufacturer_designation": "NTN 4T-623/612", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 120.65, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 190, "static_load_kN": 213, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4400, "weight_g": 2130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-623/612 is the NTN 4T catalogue entry for a 57.15×120.65×41.275 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 623/612 without it. Speed planning uses both catalogue columns: grease 3,300 r/min is the mechanical ceiling for 4T-623/612, oil 4,400 r/min with circulating oil — a 1,100 r/min margin at this size. Cup-side note for 612: within the pure-numeric inch family tables the 623 cone is listed against several cup options, and it is the cup that fixes the 120.65 mm OD and the 41.275 mm assembled width — quote the full 623/612 pair, never the cone alone. Fillet radii must clear the chamfers of the 623 cone and 612 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 120.65 mm cup with a press sleeve; at 2130 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (120.65×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 623/612 reference at purchase.", "Do not confuse T (41.275 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ABMA makes the 57.15×120.65 mm envelope interchangeable, not the ratings: NTN prints 190/213 kN for this execution and another make of the same number can differ in roller complement.", "The 190/213 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-623/612; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-623/612?", "a": "4T-623/612 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 120.65 mm outside diameter and 41.275 mm assembled width T (4.75 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 190 kN, C0 213 kN, grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 2130 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-623/612 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 623 cone or the 612 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 190/213 kN ratings change with the cup." }, { "q": "What is the difference between 4T-623/612 and a metric ISO 355 tapered bearing?", "a": "4T-623/612 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×120.65×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-623/612 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 623/612 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-623/612 list two speeds, 3,300 and 4,400 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-623/612 at 4,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "623", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-623-612", "623-612", "4T-623-612" ], "locale_variants": {} }, { "sku": "555S-552A", "brand": "NTN", "manufacturer_designation": "NTN 4T-555S/552A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 123.825, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 175, "static_load_kN": 216, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4100, "weight_g": 2170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-555S/552A denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 555S and cup 552A delivered as a matched, separable pair of 57.15 mm bore and 123.825 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 555S identifies the cone of 57.15 mm (2.25 in) bore by catalogue lookup, and 552A fixes the 123.825 mm OD. Grease relubrication at the 3,000 r/min limiting speed targets the cone-rib contact; sustaining 4,100 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-555S/552A: press the 552A cup square into the 123.825 mm seat first, then bring the 555S cone (on its 57.15 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-555S/552A sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 123.825 mm cup with a press sleeve; at 2170 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (123.825×38.1 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 555S/552A reference at purchase.", "Grease packs must leave free volume inside the 38.1 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,100 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 57.15 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "An unloaded 4T-555S/552A near 3,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 175/216 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-555S/552A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-555S/552A?", "a": "4T-555S/552A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 123.825 mm outside diameter and 38.1 mm assembled width T (4.875 × 1.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 175 kN, C0 216 kN, grease limiting speed 3,000 r/min, oil speed 4,100 r/min, mass about 2170 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-555S/552A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 555S cone or the 552A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 175/216 kN ratings change with the cup." }, { "q": "What is the difference between 4T-555S/552A and a metric ISO 355 tapered bearing?", "a": "4T-555S/552A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×123.825×38.1 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-555S/552A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 555S/552A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-555S/552A list two speeds, 3,000 and 4,100 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-555S/552A at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "555S", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-555s-552a", "555s-552a", "555S-552A", "4T-555S-552A" ], "locale_variants": {} }, { "sku": "72225C-72487", "brand": "NTN", "manufacturer_designation": "NTN 4T-72225C/72487", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 123.825, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 171, "static_load_kN": 188, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3900, "weight_g": 1960, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 57.15 mm carrying combined radial and thrust load, NTN lists 4T-72225C/72487, a single-row 4T tapered roller set of 171 kN C and 188 kN C0 inside the 123.825 mm OD cup. Reading the designation: 4T-72225C/72487 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Speed planning uses both catalogue columns: grease 2,900 r/min is the mechanical ceiling for 4T-72225C/72487, oil 3,900 r/min with circulating oil — a 1,000 r/min margin at this size. The printed 171/188 kN ratings belong to the assembled 72225C+72487 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 72225C cone and 72487 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 123.825 mm cup with a press sleeve; at 1960 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (123.825×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 72225C/72487 reference at purchase.", "Grease packs must leave free volume inside the 36.512 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,900 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of 72225C and 72487; use undercut shoulders so the rings seat on the face, not on a radius.", "Open 4T-72225C/72487 sets have no seals: a hub or gearbox needs external sealing or the 2,900 r/min grease figure is meaningless once water reaches the cone rib.", "The 171/188 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-72225C/72487; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-72225C/72487?", "a": "4T-72225C/72487 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 123.825 mm outside diameter and 36.512 mm assembled width T (4.875 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 171 kN, C0 188 kN, grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 1960 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-72225C/72487 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 72225C cone or the 72487 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 171/188 kN ratings change with the cup." }, { "q": "What is the difference between 4T-72225C/72487 and a metric ISO 355 tapered bearing?", "a": "4T-72225C/72487 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×123.825×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-72225C/72487 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 72225C/72487 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-72225C/72487 list two speeds, 2,900 and 3,900 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-72225C/72487 at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "72225C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-72225c-72487", "72225c-72487", "72225C-72487", "4T-72225C-72487" ], "locale_variants": {} }, { "sku": "78225-78551", "brand": "NTN", "manufacturer_designation": "NTN 4T-78225/78551", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.15, "D_mm": 140.03, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 190, "static_load_kN": 212, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3400, "weight_g": 2690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-78225/78551 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 78225 and cup 78551 delivered as a matched, separable pair of 57.15 mm bore and 140.03 mm outside diameter. Cone and cup of 4T-78225/78551 are separately stocked parts: a worn 78551 cup can be replaced against the existing 78225 cone, provided the new cup carries the identical reference — pairing across references changes the 36.512 mm assembled width and the rating. The 41.4 mm radial section over the 57.15 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 190/212 kN ratings belong to the assembled 78225+78551 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-78225/78551 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 57.15 mm cone by induction heating (max 120 °C) and the 140.03 mm cup with a press sleeve; at 2690 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.15 mm bore (140.03×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 78225/78551 reference at purchase.", "Quote the full 78225/78551 pair at ordering: the 78225 cone also ships against sibling cups, and a cup from another reference changes the 36.512 mm assembled width and the rating.", "ABMA makes the 57.15×140.03 mm envelope interchangeable, not the ratings: NTN prints 190/212 kN for this execution and another make of the same number can differ in roller complement.", "Open 4T-78225/78551 sets have no seals: a hub or gearbox needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 190/212 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-78225/78551; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-78225/78551?", "a": "4T-78225/78551 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.15 mm bore (2.25 in), 140.03 mm outside diameter and 36.512 mm assembled width T (5.513 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 190 kN, C0 212 kN, grease limiting speed 2,600 r/min, oil speed 3,400 r/min, mass about 2690 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-78225/78551 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 78225 cone or the 78551 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 190/212 kN ratings change with the cup." }, { "q": "What is the difference between 4T-78225/78551 and a metric ISO 355 tapered bearing?", "a": "4T-78225/78551 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.15×140.03×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-78225/78551 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 78225/78551 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-78225/78551 list two speeds, 2,600 and 3,400 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-78225/78551 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "78225", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-78225-78551", "78225-78551", "4T-78225-78551" ], "locale_variants": {} }, { "sku": "388A-382A", "brand": "NTN", "manufacturer_designation": "NTN 4T-388A/382A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 57.531, "D_mm": 96.838, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 86.5, "static_load_kN": 96.5, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 5000, "weight_g": 574, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-388A/382A is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 57.531×96.838×21 mm (assembled width T), for a shaft of about 57.531 mm (2.265 in). Cone and cup of 4T-388A/382A are separately stocked parts: a worn 382A cup can be replaced against the existing 388A cone, provided the new cup carries the identical reference — pairing across references changes the 21 mm assembled width and the rating. Catalogue mass of the 4T-388A/382A cone-plus-cup set is 574 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-388A/382A: press the 382A cup square into the 96.838 mm seat first, then bring the 388A cone (on its 57.531 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 57.531 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 57.531 mm cone by induction heating (max 120 °C) and the 96.838 mm cup with a press sleeve; at 574 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 57.531 mm bore (96.838×21 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 388A/382A reference at purchase.", "Inch and metric bores collide on paper — 57.531 mm is 2.265 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Never drive the 96.838 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "An unloaded 4T-388A/382A near 3,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 86.5/96.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-388A/382A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-388A/382A?", "a": "4T-388A/382A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 57.531 mm bore (2.265 in), 96.838 mm outside diameter and 21 mm assembled width T (3.813 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 86.5 kN, C0 96.5 kN, grease limiting speed 3,700 r/min, oil speed 5,000 r/min, mass about 574 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-388A/382A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 388A cone or the 382A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 86.5/96.5 kN ratings change with the cup." }, { "q": "What is the difference between 4T-388A/382A and a metric ISO 355 tapered bearing?", "a": "4T-388A/382A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 57.531×96.838×21 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-388A/382A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 388A/382A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-388A/382A list two speeds, 3,700 and 5,000 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-388A/382A at 5,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "388A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "388a-382a", "4t-388a-382a", "388A-382A", "4T-388A-382A" ], "locale_variants": {} }, { "sku": "66589-66520", "brand": "NTN", "manufacturer_designation": "NTN 4T-66589/66520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 59.972, "D_mm": 122.238, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 149, "static_load_kN": 163, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4200, "weight_g": 1660, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-66589/66520 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 59.972×122.238×33.338 mm (assembled width T), for a shaft of about 59.972 mm (2.361 in). Cone and cup of 4T-66589/66520 are separately stocked parts: a worn 66520 cup can be replaced against the existing 66589 cone, provided the new cup carries the identical reference — pairing across references changes the 33.338 mm assembled width and the rating. The 31.1 mm radial section over the 59.972 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 149/163 kN ratings belong to the assembled 66589+66520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-66589/66520 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 59.972 mm cone by induction heating (max 120 °C) and the 122.238 mm cup with a press sleeve; at 1660 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 59.972 mm bore (122.238×33.338 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 66589/66520 reference at purchase.", "Never drive the 122.238 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume inside the 33.338 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,200 r/min raises temperature and destroys the setting.", "ABMA makes the 59.972×122.238 mm envelope interchangeable, not the ratings: NTN prints 149/163 kN for this execution and another make of the same number can differ in roller complement.", "The 149/163 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-66589/66520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-66589/66520?", "a": "4T-66589/66520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 59.972 mm bore (2.361 in), 122.238 mm outside diameter and 33.338 mm assembled width T (4.813 × 1.313 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 149 kN, C0 163 kN, grease limiting speed 3,100 r/min, oil speed 4,200 r/min, mass about 1660 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-66589/66520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 66589 cone or the 66520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 149/163 kN ratings change with the cup." }, { "q": "What is the difference between 4T-66589/66520 and a metric ISO 355 tapered bearing?", "a": "4T-66589/66520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 59.972×122.238×33.338 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-66589/66520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 66589/66520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-66589/66520 list two speeds, 3,100 and 4,200 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-66589/66520 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "66589", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-66589-66520", "66589-66520", "4T-66589-66520" ], "locale_variants": {} }, { "sku": "H913840-H913810", "brand": "NTN", "manufacturer_designation": "NTN 4T-H913840/H913810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 59.987, "D_mm": 146.05, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 220, "static_load_kN": 234, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3220, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.362 in (59.987 mm) shaft position as 4T-H913840/H913810: cone H913840, cup H913810, profiled rollers and a pressed-steel cage, rated 220 kN basic dynamic and 234 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote H913840/H913810 without it. Imperial cross-check for the drawing: 59.987×146.05×41.275 mm converts to 2.362 × 5.75 × 1.625 in; the ABMA envelope swaps with like-numbered inch parts but the 220/234 kN ratings are NTN-specific. Cup-side note for H913810: within the heavy H family tables the H913840 cone is listed against several cup options, and it is the cup that fixes the 146.05 mm OD and the 41.275 mm assembled width — quote the full H913840/H913810 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-H913840/H913810 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 59.987 mm cone by induction heating (max 120 °C) and the 146.05 mm cup with a press sleeve; at 3220 g a cocked ring brinells the raceway directly.", "The heavy H family at 59.987 mm bore (146.05×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full H913840/H913810 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of H913840 and H913810; use undercut shoulders so the rings seat on the face, not on a radius.", "Do not confuse T (41.275 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Quote the full H913840/H913810 pair at ordering: the H913840 cone also ships against sibling cups, and a cup from another reference changes the 41.275 mm assembled width and the rating.", "The 220/234 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-H913840/H913810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-H913840/H913810?", "a": "4T-H913840/H913810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 59.987 mm bore (2.362 in), 146.05 mm outside diameter and 41.275 mm assembled width T (5.75 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 220 kN, C0 234 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3220 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-H913840/H913810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the H913840 cone or the H913810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 220/234 kN ratings change with the cup." }, { "q": "What is the difference between 4T-H913840/H913810 and a metric ISO 355 tapered bearing?", "a": "4T-H913840/H913810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 59.987×146.05×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-H913840/H913810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare H913840/H913810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-H913840/H913810 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-H913840/H913810 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "H913840", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-h913840-h913810", "h913840-h913810", "H913840-H913810", "4T-H913840-H913810" ], "locale_variants": {} }, { "sku": "JLM508748-JLM508710", "brand": "NTN", "manufacturer_designation": "NTN 4T-JLM508748/JLM508710", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 95, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 92.5, "static_load_kN": 122, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 609, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 60 mm carrying combined radial and thrust load, NTN lists 4T-JLM508748/JLM508710, a single-row 4T tapered roller set of 92.5 kN C and 122 kN C0 inside the 95 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — JLM508748 sits in the JLM prefixed family. Grease relubrication at the 3,700 r/min limiting speed targets the cone-rib contact; sustaining 4,900 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-JLM508748/JLM508710: press the JLM508710 cup square into the 95 mm seat first, then bring the JLM508748 cone (on its 60 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-JLM508748/JLM508710; reverse the fit logic when the cup rotates.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the 95 mm cup with a press sleeve; at 609 g a cocked ring brinells the raceway directly.", "The J-prefixed JLM508748 code belongs to a metric-envelope inch family: its 60 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Quote the full JLM508748/JLM508710 pair at ordering: the JLM508748 cone also ships against sibling cups, and a cup from another reference changes the 24 mm assembled width and the rating.", "Replacing one half of an adjusted pair without resetting end play negates the 24 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Shaft and housing fillets must clear the ring chamfers of JLM508748 and JLM508710; use undercut shoulders so the rings seat on the face, not on a radius.", "The 92.5/122 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JLM508748/JLM508710; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JLM508748/JLM508710?", "a": "4T-JLM508748/JLM508710 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60 mm bore (2.362 in), 95 mm outside diameter and 24 mm assembled width T (3.74 × 0.945 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 92.5 kN, C0 122 kN, grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 609 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JLM508748/JLM508710 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JLM508748 cone or the JLM508710 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 92.5/122 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JLM508748/JLM508710 and a metric ISO 355 tapered bearing?", "a": "4T-JLM508748/JLM508710 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60×95×24 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JLM508748/JLM508710 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JLM508748/JLM508710 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JLM508748/JLM508710 list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JLM508748/JLM508710 at 4,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JLM508748", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jlm508748-jlm508710", "4t-jlm508748-jlm508710", "jlm508748-jlm508710", "JLM508748-JLM508710", "4T-JLM508748-JLM508710" ], "locale_variants": {} }, { "sku": "29580-29520", "brand": "NTN", "manufacturer_designation": "NTN 4T-29580/29520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 107.95, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 101, "static_load_kN": 140, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 992, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 60 mm carrying combined radial and thrust load, NTN lists 4T-29580/29520, a single-row 4T tapered roller set of 101 kN C and 140 kN C0 inside the 107.95 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 29580 identifies the cone of 60 mm (2.362 in) bore by catalogue lookup, and 29520 fixes the 107.95 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 25.4 mm T of each 4T-29580/29520 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 101/140 kN ratings belong to the assembled 29580+29520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 60 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the 107.95 mm cup with a press sleeve; at 992 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 60 mm bore (107.95×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 29580/29520 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 60 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 60 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Inch and metric bores collide on paper — 60 mm is 2.362 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 101/140 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-29580/29520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-29580/29520?", "a": "4T-29580/29520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60 mm bore (2.362 in), 107.95 mm outside diameter and 25.4 mm assembled width T (4.25 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 101 kN, C0 140 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 992 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-29580/29520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 29580 cone or the 29520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 101/140 kN ratings change with the cup." }, { "q": "What is the difference between 4T-29580/29520 and a metric ISO 355 tapered bearing?", "a": "4T-29580/29520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60×107.95×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-29580/29520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 29580/29520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-29580/29520 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-29580/29520 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "29580", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=185", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-29580-29520", "29580-29520", "4T-29580-29520" ], "locale_variants": {} }, { "sku": "397-394A", "brand": "NTN", "manufacturer_designation": "NTN 4T-397/394A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 110, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 99.5, "static_load_kN": 120, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 918, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-397/394A denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 397 and cup 394A delivered as a matched, separable pair of 60 mm bore and 110 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 397 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 3,200 r/min is the mechanical ceiling for 4T-397/394A, oil 4,300 r/min with circulating oil — a 1,100 r/min margin at this size. Cup-side note for 394A: within the pure-numeric inch family tables the 397 cone is listed against several cup options, and it is the cup that fixes the 110 mm OD and the 22 mm assembled width — quote the full 397/394A pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-397/394A run near 3,200 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the 110 mm cup with a press sleeve; at 918 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 60 mm bore (110×22 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 397/394A reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 397 and 394A; use undercut shoulders so the rings seat on the face, not on a radius.", "Fit selection follows the rotating ring: a rotating cone on a 60 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Never drive the 110 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 99.5/120 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-397/394A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-397/394A?", "a": "4T-397/394A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60 mm bore (2.362 in), 110 mm outside diameter and 22 mm assembled width T (4.331 × 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 99.5 kN, C0 120 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 918 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-397/394A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 397 cone or the 394A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 99.5/120 kN ratings change with the cup." }, { "q": "What is the difference between 4T-397/394A and a metric ISO 355 tapered bearing?", "a": "4T-397/394A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60×110×22 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-397/394A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 397/394A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-397/394A list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-397/394A at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "397", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "397-394a", "4t-397-394a", "397-394A", "4T-397-394A" ], "locale_variants": {} }, { "sku": "JHM911244-JHM911211", "brand": "NTN", "manufacturer_designation": "NTN 4T-JHM911244/JHM911211", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60, "D_mm": 130, "B_mm": 34.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 173, "static_load_kN": 186, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 2010, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JHM911244/JHM911211 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 60×130×34.1 mm (assembled width T), for a shaft of about 60 mm (2.362 in). Cone and cup of 4T-JHM911244/JHM911211 are separately stocked parts: a worn JHM911211 cup can be replaced against the existing JHM911244 cone, provided the new cup carries the identical reference — pairing across references changes the 34.1 mm assembled width and the rating. Catalogue mass of the 4T-JHM911244/JHM911211 cone-plus-cup set is 2010 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 173/186 kN ratings belong to the assembled JHM911244+JHM911211 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-JHM911244/JHM911211 run near 2,700 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 60 mm cone by induction heating (max 120 °C) and the 130 mm cup with a press sleeve; at 2010 g a cocked ring brinells the raceway directly.", "The J-prefixed JHM911244 code belongs to a metric-envelope inch family: its 60 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Do not confuse T (34.1 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Inch and metric bores collide on paper — 60 mm is 2.362 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 34.1 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,600 r/min raises temperature and destroys the setting.", "The 173/186 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JHM911244/JHM911211; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JHM911244/JHM911211?", "a": "4T-JHM911244/JHM911211 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60 mm bore (2.362 in), 130 mm outside diameter and 34.1 mm assembled width T (5.118 × 1.343 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 173 kN, C0 186 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 2010 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JHM911244/JHM911211 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JHM911244 cone or the JHM911211 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 173/186 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JHM911244/JHM911211 and a metric ISO 355 tapered bearing?", "a": "4T-JHM911244/JHM911211 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60×130×34.1 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JHM911244/JHM911211 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JHM911244/JHM911211 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JHM911244/JHM911211 list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JHM911244/JHM911211 at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JHM911244", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jhm911244-jhm911211", "4t-jhm911244-jhm911211", "jhm911244-jhm911211", "JHM911244-JHM911211", "4T-JHM911244-JHM911211" ], "locale_variants": {} }, { "sku": "28985-28921", "brand": "NTN", "manufacturer_designation": "NTN 4T-28985/28921", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60.325, "D_mm": 100, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 100, "static_load_kN": 134, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 769, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 60.325 mm carrying combined radial and thrust load, NTN lists 4T-28985/28921, a single-row 4T tapered roller set of 100 kN C and 134 kN C0 inside the 100 mm OD cup. Cone and cup of 4T-28985/28921 are separately stocked parts: a worn 28921 cup can be replaced against the existing 28985 cone, provided the new cup carries the identical reference — pairing across references changes the 25.4 mm assembled width and the rating. The 19.8 mm radial section over the 60.325 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-28985/28921: press the 28921 cup square into the 100 mm seat first, then bring the 28985 cone (on its 60.325 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-28985/28921 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 60.325 mm cone by induction heating (max 120 °C) and the 100 mm cup with a press sleeve; at 769 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 60.325 mm bore (100×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28985/28921 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 60.325 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 60.325 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 28985/28921 pair at ordering: the 28985 cone also ships against sibling cups, and a cup from another reference changes the 25.4 mm assembled width and the rating.", "The 100/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28985/28921; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28985/28921?", "a": "4T-28985/28921 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60.325 mm bore (2.375 in), 100 mm outside diameter and 25.4 mm assembled width T (3.937 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 100 kN, C0 134 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 769 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28985/28921 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28985 cone or the 28921 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 100/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28985/28921 and a metric ISO 355 tapered bearing?", "a": "4T-28985/28921 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60.325×100×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28985/28921 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28985/28921 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28985/28921 list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28985/28921 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28985", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28985-28921", "28985-28921", "4T-28985-28921" ], "locale_variants": {} }, { "sku": "3980-3920", "brand": "NTN", "manufacturer_designation": "NTN 4T-3980/3920", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60.325, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 132, "static_load_kN": 174, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 1340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3980/3920 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-3980/3920 are separately stocked parts: a worn 3920 cup can be replaced against the existing 3980 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. The 2.2 kN of dynamic capacity per millimetre of bore summarises the 132 kN rating over the 60.325 mm bore — sanity-check any interchange candidate against this ratio and the 30.162 mm T. The printed 132/174 kN ratings belong to the assembled 3980+3920 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-3980/3920 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 60.325 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 1340 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 60.325 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3980/3920 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 3980 and 3920; use undercut shoulders so the rings seat on the face, not on a radius.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 60.325 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 132/174 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3980/3920; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3980/3920?", "a": "4T-3980/3920 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60.325 mm bore (2.375 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 132 kN, C0 174 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 1340 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3980/3920 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3980 cone or the 3920 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 132/174 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3980/3920 and a metric ISO 355 tapered bearing?", "a": "4T-3980/3920 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60.325×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3980/3920 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3980/3920 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3980/3920 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3980/3920 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3980", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3980-3920", "3980-3920", "4T-3980-3920" ], "locale_variants": {} }, { "sku": "5583-5535", "brand": "NTN", "manufacturer_designation": "NTN 4T-5583/5535", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60.325, "D_mm": 122.238, "B_mm": 43.658, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 215, "static_load_kN": 283, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 2450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-5583/5535 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 5583 and cup 5535 delivered as a matched, separable pair of 60.325 mm bore and 122.238 mm outside diameter. Reading the designation: 4T-5583/5535 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Speed planning uses both catalogue columns: grease 3,100 r/min is the mechanical ceiling for 4T-5583/5535, oil 4,100 r/min with circulating oil — a 1,000 r/min margin at this size. Cup-side note for 5535: within the pure-numeric inch family tables the 5583 cone is listed against several cup options, and it is the cup that fixes the 122.238 mm OD and the 43.658 mm assembled width — quote the full 5583/5535 pair, never the cone alone. Fillet radii must clear the chamfers of the 5583 cone and 5535 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 60.325 mm cone by induction heating (max 120 °C) and the 122.238 mm cup with a press sleeve; at 2450 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 60.325 mm bore (122.238×43.658 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 5583/5535 reference at purchase.", "Grease packs must leave free volume inside the 43.658 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,100 r/min raises temperature and destroys the setting.", "Replacing one half of an adjusted pair without resetting end play negates the 43.658 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ABMA makes the 60.325×122.238 mm envelope interchangeable, not the ratings: NTN prints 215/283 kN for this execution and another make of the same number can differ in roller complement.", "The 215/283 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-5583/5535; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-5583/5535?", "a": "4T-5583/5535 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60.325 mm bore (2.375 in), 122.238 mm outside diameter and 43.658 mm assembled width T (4.813 × 1.719 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 215 kN, C0 283 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 2450 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-5583/5535 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 5583 cone or the 5535 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 215/283 kN ratings change with the cup." }, { "q": "What is the difference between 4T-5583/5535 and a metric ISO 355 tapered bearing?", "a": "4T-5583/5535 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60.325×122.238×43.658 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-5583/5535 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 5583/5535 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-5583/5535 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-5583/5535 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "5583", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-5583-5535", "5583-5535", "4T-5583-5535" ], "locale_variants": {} }, { "sku": "HM212044-HM212011", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM212044/HM212011", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60.325, "D_mm": 122.238, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 208, "static_load_kN": 244, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 2020, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.375 in (60.325 mm) shaft position as 4T-HM212044/HM212011: cone HM212044, cup HM212011, profiled rollers and a pressed-steel cage, rated 208 kN basic dynamic and 244 kN static. Reading the designation: 4T-HM212044/HM212011 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the heavy-medium HM family lettering ties the pair to its boundary plan. Contact-angle geometry of the heavy-medium HM family gives 4T-HM212044/HM212011 its radial/axial load split — at 208/244 kN the static rating is about 1.17× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for HM212011: within the heavy-medium HM family tables the HM212044 cone is listed against several cup options, and it is the cup that fixes the 122.238 mm OD and the 38.1 mm assembled width — quote the full HM212044/HM212011 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 60.325 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 60.325 mm cone by induction heating (max 120 °C) and the 122.238 mm cup with a press sleeve; at 2020 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 60.325 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Fit selection follows the rotating ring: a rotating cone on a 60.325 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of HM212044 and HM212011; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of HM212044 and HM212011; use undercut shoulders so the rings seat on the face, not on a radius.", "The 208/244 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM212044/HM212011; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM212044/HM212011?", "a": "4T-HM212044/HM212011 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60.325 mm bore (2.375 in), 122.238 mm outside diameter and 38.1 mm assembled width T (4.813 × 1.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 208 kN, C0 244 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 2020 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM212044/HM212011 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM212044 cone or the HM212011 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 208/244 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM212044/HM212011 and a metric ISO 355 tapered bearing?", "a": "4T-HM212044/HM212011 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60.325×122.238×38.1 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM212044/HM212011 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM212044/HM212011 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM212044/HM212011 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM212044/HM212011 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM212044", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm212044-hm212011", "hm212044-hm212011", "HM212044-HM212011", "4T-HM212044-HM212011" ], "locale_variants": {} }, { "sku": "558-552A", "brand": "NTN", "manufacturer_designation": "NTN 4T-558/552A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60.325, "D_mm": 123.825, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 175, "static_load_kN": 216, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4100, "weight_g": 2090, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-558/552A belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 558 identifies the cone of 60.325 mm (2.375 in) bore by catalogue lookup, and 552A fixes the 123.825 mm OD. Contact-angle geometry of the pure-numeric inch family gives 4T-558/552A its radial/axial load split — at 175/216 kN the static rating is about 1.23× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-558/552A: press the 552A cup square into the 123.825 mm seat first, then bring the 558 cone (on its 60.325 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Contact-pattern check with marking blue: a pattern biased to one roller end means the 60.325 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 60.325 mm cone by induction heating (max 120 °C) and the 123.825 mm cup with a press sleeve; at 2090 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 60.325 mm bore (123.825×38.1 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 558/552A reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 60.325 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 558/552A pair at ordering: the 558 cone also ships against sibling cups, and a cup from another reference changes the 38.1 mm assembled width and the rating.", "Do not confuse T (38.1 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 175/216 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-558/552A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-558/552A?", "a": "4T-558/552A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60.325 mm bore (2.375 in), 123.825 mm outside diameter and 38.1 mm assembled width T (4.875 × 1.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 175 kN, C0 216 kN, grease limiting speed 3,000 r/min, oil speed 4,100 r/min, mass about 2090 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-558/552A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 558 cone or the 552A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 175/216 kN ratings change with the cup." }, { "q": "What is the difference between 4T-558/552A and a metric ISO 355 tapered bearing?", "a": "4T-558/552A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60.325×123.825×38.1 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-558/552A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 558/552A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-558/552A list two speeds, 3,000 and 4,100 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-558/552A at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "558", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-558-552a", "558-552a", "558-552A", "4T-558-552A" ], "locale_variants": {} }, { "sku": "65237-65500", "brand": "NTN", "manufacturer_designation": "NTN 4T-65237/65500", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60.325, "D_mm": 127, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 226, "static_load_kN": 263, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4200, "weight_g": 2590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-65237/65500 at 60.325 mm bore (2.375 in), 127 mm cup OD and 44.45 mm assembled T, with a grease limiting speed of 3,100 r/min and an oil ceiling of 4,200 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 65237/65500 without it. Grease relubrication at the 3,100 r/min limiting speed targets the cone-rib contact; sustaining 4,200 r/min needs an oil supply directed at the large roller ends. Cup-side note for 65500: within the pure-numeric inch family tables the 65237 cone is listed against several cup options, and it is the cup that fixes the 127 mm OD and the 44.45 mm assembled width — quote the full 65237/65500 pair, never the cone alone. Fillet radii must clear the chamfers of the 65237 cone and 65500 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 60.325 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 2590 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 60.325 mm bore (127×44.45 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 65237/65500 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 60.325 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 65237/65500 pair at ordering: the 65237 cone also ships against sibling cups, and a cup from another reference changes the 44.45 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of 65237 and 65500; use undercut shoulders so the rings seat on the face, not on a radius.", "The 226/263 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-65237/65500; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-65237/65500?", "a": "4T-65237/65500 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60.325 mm bore (2.375 in), 127 mm outside diameter and 44.45 mm assembled width T (5 × 1.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 226 kN, C0 263 kN, grease limiting speed 3,100 r/min, oil speed 4,200 r/min, mass about 2590 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-65237/65500 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 65237 cone or the 65500 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 226/263 kN ratings change with the cup." }, { "q": "What is the difference between 4T-65237/65500 and a metric ISO 355 tapered bearing?", "a": "4T-65237/65500 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60.325×127×44.45 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-65237/65500 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 65237/65500 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-65237/65500 list two speeds, 3,100 and 4,200 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-65237/65500 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "65237", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-65237-65500", "65237-65500", "4T-65237-65500" ], "locale_variants": {} }, { "sku": "HM813841-HM813810", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM813841/HM813810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60.325, "D_mm": 127, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 181, "static_load_kN": 228, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 2210, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM813841/HM813810 is the NTN 4T catalogue entry for a 60.325×127×36.512 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-HM813841/HM813810 are separately stocked parts: a worn HM813810 cup can be replaced against the existing HM813841 cone, provided the new cup carries the identical reference — pairing across references changes the 36.512 mm assembled width and the rating. Catalogue mass of the 4T-HM813841/HM813810 cone-plus-cup set is 2210 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-HM813841/HM813810: press the HM813810 cup square into the 127 mm seat first, then bring the HM813841 cone (on its 60.325 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-HM813841/HM813810 run near 2,900 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 60.325 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 2210 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 60.325 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Replacing one half of an adjusted pair without resetting end play negates the 36.512 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Grease packs must leave free volume inside the 36.512 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,800 r/min raises temperature and destroys the setting.", "An unloaded 4T-HM813841/HM813810 near 2,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 181/228 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM813841/HM813810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM813841/HM813810?", "a": "4T-HM813841/HM813810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60.325 mm bore (2.375 in), 127 mm outside diameter and 36.512 mm assembled width T (5 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 228 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 2210 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM813841/HM813810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM813841 cone or the HM813810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 181/228 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM813841/HM813810 and a metric ISO 355 tapered bearing?", "a": "4T-HM813841/HM813810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60.325×127×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM813841/HM813810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM813841/HM813810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM813841/HM813810 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM813841/HM813810 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM813841", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm813841-hm813810", "hm813841-hm813810", "HM813841-HM813810", "4T-HM813841-HM813810" ], "locale_variants": {} }, { "sku": "HM911245-HM911210", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM911245/HM911210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 60.325, "D_mm": 130.175, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 173, "static_load_kN": 186, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 2120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-HM911245/HM911210 denotes the heavy-medium HM family of NTN inch tapered roller bearings — cone HM911245 and cup HM911210 delivered as a matched, separable pair of 60.325 mm bore and 130.175 mm outside diameter. Reading the designation: 4T-HM911245/HM911210 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the heavy-medium HM family lettering ties the pair to its boundary plan. Grease relubrication at the 2,700 r/min limiting speed targets the cone-rib contact; sustaining 3,600 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-HM911245/HM911210: press the HM911210 cup square into the 130.175 mm seat first, then bring the HM911245 cone (on its 60.325 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 60.325 mm cone with an induction heater (max 120 °C) and press the 130.175 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 60.325 mm cone by induction heating (max 120 °C) and the 130.175 mm cup with a press sleeve; at 2120 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 60.325 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "An unloaded 4T-HM911245/HM911210 near 2,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of HM911245 and HM911210; use undercut shoulders so the rings seat on the face, not on a radius.", "Never drive the 130.175 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 173/186 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM911245/HM911210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM911245/HM911210?", "a": "4T-HM911245/HM911210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 60.325 mm bore (2.375 in), 130.175 mm outside diameter and 36.512 mm assembled width T (5.125 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 173 kN, C0 186 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 2120 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM911245/HM911210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM911245 cone or the HM911210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 173/186 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM911245/HM911210 and a metric ISO 355 tapered bearing?", "a": "4T-HM911245/HM911210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 60.325×130.175×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM911245/HM911210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM911245/HM911210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM911245/HM911210 list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM911245/HM911210 at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM911245-210", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm911245-hm911210", "hm911245-hm911210", "HM911245-HM911210", "4T-HM911245-HM911210" ], "locale_variants": {} }, { "sku": "392-394A", "brand": "NTN", "manufacturer_designation": "NTN 4T-392/394A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 61.912, "D_mm": 110, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 99.5, "static_load_kN": 120, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 880, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 61.912 mm carrying combined radial and thrust load, NTN lists 4T-392/394A, a single-row 4T tapered roller set of 99.5 kN C and 120 kN C0 inside the 110 mm OD cup. Reading the designation: 4T-392/394A follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 3,200 r/min limiting speed targets the cone-rib contact; sustaining 4,300 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-392/394A: press the 394A cup square into the 110 mm seat first, then bring the 392 cone (on its 61.912 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-392/394A; reverse the fit logic when the cup rotates.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 61.912 mm cone by induction heating (max 120 °C) and the 110 mm cup with a press sleeve; at 880 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 61.912 mm bore (110×22 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 392/394A reference at purchase.", "Quote the full 392/394A pair at ordering: the 392 cone also ships against sibling cups, and a cup from another reference changes the 22 mm assembled width and the rating.", "Grease packs must leave free volume inside the 22 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,300 r/min raises temperature and destroys the setting.", "Do not confuse T (22 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 99.5/120 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-392/394A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-392/394A?", "a": "4T-392/394A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 61.912 mm bore (2.437 in), 110 mm outside diameter and 22 mm assembled width T (4.331 × 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 99.5 kN, C0 120 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 880 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-392/394A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 392 cone or the 394A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 99.5/120 kN ratings change with the cup." }, { "q": "What is the difference between 4T-392/394A and a metric ISO 355 tapered bearing?", "a": "4T-392/394A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 61.912×110×22 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-392/394A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 392/394A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-392/394A list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-392/394A at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "392", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "392-394a", "4t-392-394a", "392-394A", "4T-392-394A" ], "locale_variants": {} }, { "sku": "H715334-H715311", "brand": "NTN", "manufacturer_designation": "NTN 4T-H715334/H715311", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 61.912, "D_mm": 136.525, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 248, "static_load_kN": 355, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 3470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 61.912 mm carrying combined radial and thrust load, NTN lists 4T-H715334/H715311, a single-row 4T tapered roller set of 248 kN C and 355 kN C0 inside the 136.525 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote H715334/H715311 without it. The 37.3 mm radial section over the 61.912 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-H715334/H715311: press the H715311 cup square into the 136.525 mm seat first, then bring the H715334 cone (on its 61.912 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-H715334/H715311 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 61.912 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 3470 g a cocked ring brinells the raceway directly.", "The heavy H family at 61.912 mm bore (136.525×46.038 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full H715334/H715311 reference at purchase.", "An unloaded 4T-H715334/H715311 near 2,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 61.912 mm is 2.437 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-H715334/H715311 sets have no seals: a hub or gearbox needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 248/355 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-H715334/H715311; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-H715334/H715311?", "a": "4T-H715334/H715311 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 61.912 mm bore (2.437 in), 136.525 mm outside diameter and 46.038 mm assembled width T (5.375 × 1.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 248 kN, C0 355 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 3470 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-H715334/H715311 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the H715334 cone or the H715311 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 248/355 kN ratings change with the cup." }, { "q": "What is the difference between 4T-H715334/H715311 and a metric ISO 355 tapered bearing?", "a": "4T-H715334/H715311 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 61.912×136.525×46.038 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-H715334/H715311 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare H715334/H715311 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-H715334/H715311 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-H715334/H715311 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "H715334", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-h715334-h715311", "h715334-h715311", "H715334-H715311", "4T-H715334-H715311" ], "locale_variants": {} }, { "sku": "H913842-H913810", "brand": "NTN", "manufacturer_designation": "NTN 4T-H913842/H913810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 61.912, "D_mm": 146.05, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 220, "static_load_kN": 234, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-H913842/H913810 at 61.912 mm bore (2.437 in), 146.05 mm cup OD and 41.275 mm assembled T, with a grease limiting speed of 2,400 r/min and an oil ceiling of 3,200 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — H913842 sits in the heavy H family. Imperial cross-check for the drawing: 61.912×146.05×41.275 mm converts to 2.437 × 5.75 × 1.625 in; the ABMA envelope swaps with like-numbered inch parts but the 220/234 kN ratings are NTN-specific. Housing fitment sequence for 4T-H913842/H913810: press the H913810 cup square into the 146.05 mm seat first, then bring the H913842 cone (on its 61.912 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 61.912 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 61.912 mm cone by induction heating (max 120 °C) and the 146.05 mm cup with a press sleeve; at 3170 g a cocked ring brinells the raceway directly.", "The heavy H family at 61.912 mm bore (146.05×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full H913842/H913810 reference at purchase.", "An unloaded 4T-H913842/H913810 near 2,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Grease packs must leave free volume inside the 41.275 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,200 r/min raises temperature and destroys the setting.", "The 220/234 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-H913842/H913810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-H913842/H913810?", "a": "4T-H913842/H913810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 61.912 mm bore (2.437 in), 146.05 mm outside diameter and 41.275 mm assembled width T (5.75 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 220 kN, C0 234 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3170 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-H913842/H913810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the H913842 cone or the H913810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 220/234 kN ratings change with the cup." }, { "q": "What is the difference between 4T-H913842/H913810 and a metric ISO 355 tapered bearing?", "a": "4T-H913842/H913810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 61.912×146.05×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-H913842/H913810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare H913842/H913810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-H913842/H913810 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-H913842/H913810 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "H913842", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-h913842-h913810", "h913842-h913810", "H913842-H913810", "4T-H913842-H913810" ], "locale_variants": {} }, { "sku": "28990-28920", "brand": "NTN", "manufacturer_designation": "NTN 4T-28990/28920", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 61.976, "D_mm": 101.6, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 100, "static_load_kN": 134, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 766, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 61.976 mm carrying combined radial and thrust load, NTN lists 4T-28990/28920, a single-row 4T tapered roller set of 100 kN C and 134 kN C0 inside the 101.6 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 28990 identifies the cone of 61.976 mm (2.44 in) bore by catalogue lookup, and 28920 fixes the 101.6 mm OD. The 19.8 mm radial section over the 61.976 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 28920: within the pure-numeric inch family tables the 28990 cone is listed against several cup options, and it is the cup that fixes the 101.6 mm OD and the 24.608 mm assembled width — quote the full 28990/28920 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-28990/28920 run near 3,500 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 61.976 mm cone by induction heating (max 120 °C) and the 101.6 mm cup with a press sleeve; at 766 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 61.976 mm bore (101.6×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28990/28920 reference at purchase.", "Inch and metric bores collide on paper — 61.976 mm is 2.44 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Never drive the 101.6 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Quote the full 28990/28920 pair at ordering: the 28990 cone also ships against sibling cups, and a cup from another reference changes the 24.608 mm assembled width and the rating.", "The 100/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28990/28920; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28990/28920?", "a": "4T-28990/28920 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 61.976 mm bore (2.44 in), 101.6 mm outside diameter and 24.608 mm assembled width T (4 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 100 kN, C0 134 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 766 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28990/28920 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28990 cone or the 28920 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 100/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28990/28920 and a metric ISO 355 tapered bearing?", "a": "4T-28990/28920 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 61.976×101.6×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28990/28920 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28990/28920 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28990/28920 list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28990/28920 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28990", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28990-28920", "28990-28920", "4T-28990-28920" ], "locale_variants": {} }, { "sku": "28995-28920", "brand": "NTN", "manufacturer_designation": "NTN 4T-28995/28920", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 62.738, "D_mm": 101.6, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 100, "static_load_kN": 134, "limiting_speed_rpm": 3500, "max_rpm": 3500, "speed_oil_rpm": 4700, "weight_g": 762, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-28995/28920 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 28995 identifies the cone of 62.738 mm (2.47 in) bore by catalogue lookup, and 28920 fixes the 101.6 mm OD. The 19.4 mm radial section over the 62.738 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 28920: within the pure-numeric inch family tables the 28995 cone is listed against several cup options, and it is the cup that fixes the 101.6 mm OD and the 25.4 mm assembled width — quote the full 28995/28920 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-28995/28920 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 62.738 mm cone by induction heating (max 120 °C) and the 101.6 mm cup with a press sleeve; at 762 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 62.738 mm bore (101.6×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 28995/28920 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 28995 and 28920; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 25.4 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,700 r/min raises temperature and destroys the setting.", "ABMA makes the 62.738×101.6 mm envelope interchangeable, not the ratings: NTN prints 100/134 kN for this execution and another make of the same number can differ in roller complement.", "The 100/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-28995/28920; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-28995/28920?", "a": "4T-28995/28920 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 62.738 mm bore (2.47 in), 101.6 mm outside diameter and 25.4 mm assembled width T (4 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 100 kN, C0 134 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 762 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-28995/28920 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 28995 cone or the 28920 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 100/134 kN ratings change with the cup." }, { "q": "What is the difference between 4T-28995/28920 and a metric ISO 355 tapered bearing?", "a": "4T-28995/28920 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 62.738×101.6×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-28995/28920 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 28995/28920 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-28995/28920 list two speeds, 3,500 and 4,700 r/min?", "a": "The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-28995/28920 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "28995", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-28995-28920", "28995-28920", "4T-28995-28920" ], "locale_variants": {} }, { "sku": "L610549-L610510", "brand": "NTN", "manufacturer_designation": "NTN 4T-L610549/L610510", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 94.458, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 67, "static_load_kN": 103, "limiting_speed_rpm": 3600, "max_rpm": 3600, "speed_oil_rpm": 4800, "weight_g": 453, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-L610549/L610510 belongs to the NTN inch 4T tapered roller range (light L family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: L610549 identifies the cone of 63.5 mm (2.5 in) bore by catalogue lookup, and L610510 fixes the 94.458 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 19.05 mm T of each 4T-L610549/L610510 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for L610510: within the light L family tables the L610549 cone is listed against several cup options, and it is the cup that fixes the 94.458 mm OD and the 19.05 mm assembled width — quote the full L610549/L610510 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-L610549/L610510 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 94.458 mm cup with a press sleeve; at 453 g a cocked ring brinells the raceway directly.", "The light L family at 63.5 mm bore (94.458×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L610549/L610510 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of L610549 and L610510; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 63.5 mm is 2.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-L610549/L610510 sets have no seals: a hub or gearbox needs external sealing or the 3,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 67/103 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L610549/L610510; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L610549/L610510?", "a": "4T-L610549/L610510 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 94.458 mm outside diameter and 19.05 mm assembled width T (3.719 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 67 kN, C0 103 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 453 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L610549/L610510 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L610549 cone or the L610510 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 67/103 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L610549/L610510 and a metric ISO 355 tapered bearing?", "a": "4T-L610549/L610510 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×94.458×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L610549/L610510 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L610549/L610510 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L610549/L610510 list two speeds, 3,600 and 4,800 r/min?", "a": "The lower figure, 3,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L610549/L610510 at 4,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L610549", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l610549-l610510", "l610549-l610510", "L610549-L610510", "4T-L610549-L610510" ], "locale_variants": {} }, { "sku": "29585-29520", "brand": "NTN", "manufacturer_designation": "NTN 4T-29585/29520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 107.95, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 101, "static_load_kN": 140, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 924, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-29585/29520 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-29585/29520 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Selection: C 101 kN against C0 140 kN gives a C0/C ratio of 1.39 for the 63.5 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 29520: within the pure-numeric inch family tables the 29585 cone is listed against several cup options, and it is the cup that fixes the 107.95 mm OD and the 25.4 mm assembled width — quote the full 29585/29520 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-29585/29520 run near 3,200 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 107.95 mm cup with a press sleeve; at 924 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (107.95×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 29585/29520 reference at purchase.", "Inch and metric bores collide on paper — 63.5 mm is 2.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Replacing one half of an adjusted pair without resetting end play negates the 25.4 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 63.5 mm is 2.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 101/140 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-29585/29520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-29585/29520?", "a": "4T-29585/29520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 107.95 mm outside diameter and 25.4 mm assembled width T (4.25 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 101 kN, C0 140 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 924 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-29585/29520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 29585 cone or the 29520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 101/140 kN ratings change with the cup." }, { "q": "What is the difference between 4T-29585/29520 and a metric ISO 355 tapered bearing?", "a": "4T-29585/29520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×107.95×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-29585/29520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 29585/29520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-29585/29520 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-29585/29520 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "29585-29521", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-29585 paired with a different cup (29521): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-29585-29520", "29585-29520", "4T-29585-29520" ], "locale_variants": {} }, { "sku": "29586-29520", "brand": "NTN", "manufacturer_designation": "NTN 4T-29586/29520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 107.95, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 101, "static_load_kN": 140, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 930, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-29586/29520 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 63.5×107.95×25.4 mm (assembled width T), for a shaft of about 63.5 mm (2.5 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 29586/29520 without it. The 22.2 mm radial section over the 63.5 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 101/140 kN ratings belong to the assembled 29586+29520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-29586/29520 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 107.95 mm cup with a press sleeve; at 930 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (107.95×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 29586/29520 reference at purchase.", "An unloaded 4T-29586/29520 near 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "An unloaded 4T-29586/29520 near 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of 29586 and 29520; use undercut shoulders so the rings seat on the face, not on a radius.", "The 101/140 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-29586/29520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-29586/29520?", "a": "4T-29586/29520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 107.95 mm outside diameter and 25.4 mm assembled width T (4.25 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 101 kN, C0 140 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 930 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-29586/29520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 29586 cone or the 29520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 101/140 kN ratings change with the cup." }, { "q": "What is the difference between 4T-29586/29520 and a metric ISO 355 tapered bearing?", "a": "4T-29586/29520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×107.95×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-29586/29520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 29586/29520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-29586/29520 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-29586/29520 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "29586", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-29586-29520", "29586-29520", "4T-29586-29520" ], "locale_variants": {} }, { "sku": "29585-29521", "brand": "NTN", "manufacturer_designation": "NTN 4T-29585/29521", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 110, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 101, "static_load_kN": 140, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 982, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-29585/29521 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 63.5×110×25.4 mm (assembled width T), for a shaft of about 63.5 mm (2.5 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 29585 sits in the pure-numeric inch family. Contact-angle geometry of the pure-numeric inch family gives 4T-29585/29521 its radial/axial load split — at 101/140 kN the static rating is about 1.39× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 29521: within the pure-numeric inch family tables the 29585 cone is listed against several cup options, and it is the cup that fixes the 110 mm OD and the 25.4 mm assembled width — quote the full 29585/29521 pair, never the cone alone. Fillet radii must clear the chamfers of the 29585 cone and 29521 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 110 mm cup with a press sleeve; at 982 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (110×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 29585/29521 reference at purchase.", "Open 4T-29585/29521 sets have no seals: a hub or gearbox needs external sealing or the 3,200 r/min grease figure is meaningless once water reaches the cone rib.", "An unloaded 4T-29585/29521 near 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Grease packs must leave free volume inside the 25.4 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,300 r/min raises temperature and destroys the setting.", "The 101/140 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-29585/29521; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-29585/29521?", "a": "4T-29585/29521 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 110 mm outside diameter and 25.4 mm assembled width T (4.331 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 101 kN, C0 140 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 982 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-29585/29521 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 29585 cone or the 29521 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 101/140 kN ratings change with the cup." }, { "q": "What is the difference between 4T-29585/29521 and a metric ISO 355 tapered bearing?", "a": "4T-29585/29521 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×110×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-29585/29521 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 29585/29521 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-29585/29521 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-29585/29521 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "29585-29520", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-29585 paired with a different cup (29520): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-29585-29521", "29585-29521", "4T-29585-29521" ], "locale_variants": {} }, { "sku": "390A-394A", "brand": "NTN", "manufacturer_designation": "NTN 4T-390A/394A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 110, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 99.5, "static_load_kN": 120, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 858, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-390A/394A denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 390A and cup 394A delivered as a matched, separable pair of 63.5 mm bore and 110 mm outside diameter. Reading the designation: 4T-390A/394A follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Speed planning uses both catalogue columns: grease 3,200 r/min is the mechanical ceiling for 4T-390A/394A, oil 4,300 r/min with circulating oil — a 1,100 r/min margin at this size. Housing fitment sequence for 4T-390A/394A: press the 394A cup square into the 110 mm seat first, then bring the 390A cone (on its 63.5 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Contact-pattern check with marking blue: a pattern biased to one roller end means the 63.5 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 110 mm cup with a press sleeve; at 858 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (110×22 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 390A/394A reference at purchase.", "Never drive the 110 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never drive the 110 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Fit selection follows the rotating ring: a rotating cone on a 63.5 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 99.5/120 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-390A/394A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-390A/394A?", "a": "4T-390A/394A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 110 mm outside diameter and 22 mm assembled width T (4.331 × 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 99.5 kN, C0 120 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 858 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-390A/394A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 390A cone or the 394A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 99.5/120 kN ratings change with the cup." }, { "q": "What is the difference between 4T-390A/394A and a metric ISO 355 tapered bearing?", "a": "4T-390A/394A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×110×22 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-390A/394A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 390A/394A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-390A/394A list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-390A/394A at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "390A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "390a-394a", "4t-390a-394a", "390A-394A", "4T-390A-394A" ], "locale_variants": {} }, { "sku": "39585-39520-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-39585/39520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 195, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-39585/39520 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-39585/39520 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 24.6 mm radial section over the 63.5 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 153/195 kN ratings belong to the assembled 39585+39520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 63.5 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 1270 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 39585/39520 reference at purchase.", "Inch and metric bores collide on paper — 63.5 mm is 2.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Never drive the 112.712 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 153/195 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-39585/39520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-39585/39520?", "a": "4T-39585/39520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 195 kN, grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1270 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-39585/39520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 39585 cone or the 39520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/195 kN ratings change with the cup." }, { "q": "What is the difference between 4T-39585/39520 and a metric ISO 355 tapered bearing?", "a": "4T-39585/39520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-39585/39520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 39585/39520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-39585/39520 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-39585/39520 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "39585-39520", "equiv_brand": "SKF", "level": "partial", "note": "Same 63.5×112.712×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-39585-39520", "39585-39520", "4T-39585-39520", "39585-39520-NTN" ], "locale_variants": {} }, { "sku": "3982-3920-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-3982/3920", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 132, "static_load_kN": 174, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 1270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3982/3920 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 63.5×112.712×30.162 mm (assembled width T), for a shaft of about 63.5 mm (2.5 in). Cone and cup of 4T-3982/3920 are separately stocked parts: a worn 3920 cup can be replaced against the existing 3982 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. The 24.6 mm radial section over the 63.5 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 132/174 kN ratings belong to the assembled 3982+3920 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-3982/3920 run near 3,200 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 1270 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3982/3920 reference at purchase.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,300 r/min raises temperature and destroys the setting.", "An unloaded 4T-3982/3920 near 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 132/174 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3982/3920; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3982/3920?", "a": "4T-3982/3920 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 132 kN, C0 174 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 1270 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3982/3920 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3982 cone or the 3920 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 132/174 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3982/3920 and a metric ISO 355 tapered bearing?", "a": "4T-3982/3920 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3982/3920 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3982/3920 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3982/3920 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3982/3920 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3982-3920", "equiv_brand": "SKF", "level": "partial", "note": "Same 63.5×112.712×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3982-3920", "3982-3920", "4T-3982-3920", "3982-3920-NTN" ], "locale_variants": {} }, { "sku": "477-472", "brand": "NTN", "manufacturer_designation": "NTN 4T-477/472", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 120, "B_mm": 29.794, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 142, "static_load_kN": 177, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-477/472 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 477 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 3,000 r/min is the mechanical ceiling for 4T-477/472, oil 4,000 r/min with circulating oil — a 1,000 r/min margin at this size. Cup-side note for 472: within the pure-numeric inch family tables the 477 cone is listed against several cup options, and it is the cup that fixes the 120 mm OD and the 29.794 mm assembled width — quote the full 477/472 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 63.5 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 120 mm cup with a press sleeve; at 1600 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (120×29.794 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 477/472 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 63.5 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Replacing one half of an adjusted pair without resetting end play negates the 29.794 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Grease packs must leave free volume inside the 29.794 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,000 r/min raises temperature and destroys the setting.", "The 142/177 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-477/472; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-477/472?", "a": "4T-477/472 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 120 mm outside diameter and 29.794 mm assembled width T (4.724 × 1.173 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 142 kN, C0 177 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1600 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-477/472 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 477 cone or the 472 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 142/177 kN ratings change with the cup." }, { "q": "What is the difference between 4T-477/472 and a metric ISO 355 tapered bearing?", "a": "4T-477/472 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×120×29.794 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-477/472 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 477/472 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-477/472 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-477/472 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "477", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-477-472", "477-472", "4T-477-472" ], "locale_variants": {} }, { "sku": "483-472", "brand": "NTN", "manufacturer_designation": "NTN 4T-483/472", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 120, "B_mm": 29.794, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 142, "static_load_kN": 177, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1430, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-483/472 at 63.5 mm bore (2.5 in), 120 mm cup OD and 29.794 mm assembled T, with a grease limiting speed of 3,000 r/min and an oil ceiling of 4,000 r/min. Cone and cup of 4T-483/472 are separately stocked parts: a worn 472 cup can be replaced against the existing 483 cone, provided the new cup carries the identical reference — pairing across references changes the 29.794 mm assembled width and the rating. Grease relubrication at the 3,000 r/min limiting speed targets the cone-rib contact; sustaining 4,000 r/min needs an oil supply directed at the large roller ends. The printed 142/177 kN ratings belong to the assembled 483+472 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 483 cone and 472 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 120 mm cup with a press sleeve; at 1430 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (120×29.794 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 483/472 reference at purchase.", "Never drive the 120 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Quote the full 483/472 pair at ordering: the 483 cone also ships against sibling cups, and a cup from another reference changes the 29.794 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of 483 and 472; use undercut shoulders so the rings seat on the face, not on a radius.", "The 142/177 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-483/472; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-483/472?", "a": "4T-483/472 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 120 mm outside diameter and 29.794 mm assembled width T (4.724 × 1.173 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 142 kN, C0 177 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1430 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-483/472 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 483 cone or the 472 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 142/177 kN ratings change with the cup." }, { "q": "What is the difference between 4T-483/472 and a metric ISO 355 tapered bearing?", "a": "4T-483/472 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×120×29.794 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-483/472 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 483/472 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-483/472 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-483/472 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "483", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-483-472", "483-472", "4T-483-472" ], "locale_variants": {} }, { "sku": "5584-5535", "brand": "NTN", "manufacturer_designation": "NTN 4T-5584/5535", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 122.238, "B_mm": 43.658, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 215, "static_load_kN": 283, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 2340, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-5584/5535 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 5584 and cup 5535 delivered as a matched, separable pair of 63.5 mm bore and 122.238 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 5584 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 3,100 r/min is the mechanical ceiling for 4T-5584/5535, oil 4,100 r/min with circulating oil — a 1,000 r/min margin at this size. Housing fitment sequence for 4T-5584/5535: press the 5535 cup square into the 122.238 mm seat first, then bring the 5584 cone (on its 63.5 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-5584/5535 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 122.238 mm cup with a press sleeve; at 2340 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (122.238×43.658 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 5584/5535 reference at purchase.", "Open 4T-5584/5535 sets have no seals: a hub or gearbox needs external sealing or the 3,100 r/min grease figure is meaningless once water reaches the cone rib.", "Quote the full 5584/5535 pair at ordering: the 5584 cone also ships against sibling cups, and a cup from another reference changes the 43.658 mm assembled width and the rating.", "Open 4T-5584/5535 sets have no seals: a hub or gearbox needs external sealing or the 3,100 r/min grease figure is meaningless once water reaches the cone rib.", "The 215/283 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-5584/5535; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-5584/5535?", "a": "4T-5584/5535 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 122.238 mm outside diameter and 43.658 mm assembled width T (4.813 × 1.719 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 215 kN, C0 283 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 2340 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-5584/5535 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 5584 cone or the 5535 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 215/283 kN ratings change with the cup." }, { "q": "What is the difference between 4T-5584/5535 and a metric ISO 355 tapered bearing?", "a": "4T-5584/5535 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×122.238×43.658 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-5584/5535 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 5584/5535 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-5584/5535 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-5584/5535 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "5584", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-5584-5535", "5584-5535", "4T-5584-5535" ], "locale_variants": {} }, { "sku": "HM212046-HM212011", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM212046/HM212011", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 122.238, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 208, "static_load_kN": 244, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 63.5 mm carrying combined radial and thrust load, NTN lists 4T-HM212046/HM212011, a single-row 4T tapered roller set of 208 kN C and 244 kN C0 inside the 122.238 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HM212046 identifies the cone of 63.5 mm (2.5 in) bore by catalogue lookup, and HM212011 fixes the 122.238 mm OD. Speed planning uses both catalogue columns: grease 3,100 r/min is the mechanical ceiling for 4T-HM212046/HM212011, oil 4,100 r/min with circulating oil — a 1,000 r/min margin at this size. Cup-side note for HM212011: within the heavy-medium HM family tables the HM212046 cone is listed against several cup options, and it is the cup that fixes the 122.238 mm OD and the 38.1 mm assembled width — quote the full HM212046/HM212011 pair, never the cone alone. Fillet radii must clear the chamfers of the HM212046 cone and HM212011 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 122.238 mm cup with a press sleeve; at 1950 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 63.5 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Inch and metric bores collide on paper — 63.5 mm is 2.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "ABMA makes the 63.5×122.238 mm envelope interchangeable, not the ratings: NTN prints 208/244 kN for this execution and another make of the same number can differ in roller complement.", "Never drive the 122.238 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 208/244 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM212046/HM212011; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM212046/HM212011?", "a": "4T-HM212046/HM212011 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 122.238 mm outside diameter and 38.1 mm assembled width T (4.813 × 1.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 208 kN, C0 244 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 1950 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM212046/HM212011 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM212046 cone or the HM212011 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 208/244 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM212046/HM212011 and a metric ISO 355 tapered bearing?", "a": "4T-HM212046/HM212011 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×122.238×38.1 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM212046/HM212011 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM212046/HM212011 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM212046/HM212011 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM212046/HM212011 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM212046", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm212046-hm212011", "hm212046-hm212011", "HM212046-HM212011", "4T-HM212046-HM212011" ], "locale_variants": {} }, { "sku": "559-552A", "brand": "NTN", "manufacturer_designation": "NTN 4T-559/552A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 123.825, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 175, "static_load_kN": 216, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4100, "weight_g": 2010, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-559/552A at 63.5 mm bore (2.5 in), 123.825 mm cup OD and 38.1 mm assembled T, with a grease limiting speed of 3,000 r/min and an oil ceiling of 4,100 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 559/552A without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 38.1 mm T of each 4T-559/552A enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 552A: within the pure-numeric inch family tables the 559 cone is listed against several cup options, and it is the cup that fixes the 123.825 mm OD and the 38.1 mm assembled width — quote the full 559/552A pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-559/552A; reverse the fit logic when the cup rotates.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 123.825 mm cup with a press sleeve; at 2010 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (123.825×38.1 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 559/552A reference at purchase.", "ABMA makes the 63.5×123.825 mm envelope interchangeable, not the ratings: NTN prints 175/216 kN for this execution and another make of the same number can differ in roller complement.", "Do not confuse T (38.1 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-559/552A sets have no seals: a hub or gearbox needs external sealing or the 3,000 r/min grease figure is meaningless once water reaches the cone rib.", "The 175/216 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-559/552A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-559/552A?", "a": "4T-559/552A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 123.825 mm outside diameter and 38.1 mm assembled width T (4.875 × 1.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 175 kN, C0 216 kN, grease limiting speed 3,000 r/min, oil speed 4,100 r/min, mass about 2010 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-559/552A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 559 cone or the 552A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 175/216 kN ratings change with the cup." }, { "q": "What is the difference between 4T-559/552A and a metric ISO 355 tapered bearing?", "a": "4T-559/552A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×123.825×38.1 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-559/552A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 559/552A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-559/552A list two speeds, 3,000 and 4,100 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-559/552A at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "559", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-559-552a", "559-552a", "559-552A", "4T-559-552A" ], "locale_variants": {} }, { "sku": "565-563", "brand": "NTN", "manufacturer_designation": "NTN 4T-565/563", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 127, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 181, "static_load_kN": 229, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 2110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-565/563 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 63.5×127×36.512 mm (assembled width T), for a shaft of about 63.5 mm (2.5 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 565 identifies the cone of 63.5 mm (2.5 in) bore by catalogue lookup, and 563 fixes the 127 mm OD. The 2.9 kN of dynamic capacity per millimetre of bore summarises the 181 kN rating over the 63.5 mm bore — sanity-check any interchange candidate against this ratio and the 36.512 mm T. The printed 181/229 kN ratings belong to the assembled 565+563 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-565/563 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 2110 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (127×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 565/563 reference at purchase.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Inch and metric bores collide on paper — 63.5 mm is 2.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Replacing one half of an adjusted pair without resetting end play negates the 36.512 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 181/229 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-565/563; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-565/563?", "a": "4T-565/563 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 127 mm outside diameter and 36.512 mm assembled width T (5 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 229 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 2110 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-565/563 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 565 cone or the 563 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 181/229 kN ratings change with the cup." }, { "q": "What is the difference between 4T-565/563 and a metric ISO 355 tapered bearing?", "a": "4T-565/563 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×127×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-565/563 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 565/563 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-565/563 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-565/563 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "565", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-565-563", "565-563", "4T-565-563" ], "locale_variants": {} }, { "sku": "HM813842-HM813810", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM813842/HM813810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 127, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 181, "static_load_kN": 228, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 2130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.5 in (63.5 mm) shaft position as 4T-HM813842/HM813810: cone HM813842, cup HM813810, profiled rollers and a pressed-steel cage, rated 181 kN basic dynamic and 228 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HM813842 sits in the heavy-medium HM family. Selection: C 181 kN against C0 228 kN gives a C0/C ratio of 1.26 for the 63.5 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for HM813810: within the heavy-medium HM family tables the HM813842 cone is listed against several cup options, and it is the cup that fixes the 127 mm OD and the 36.512 mm assembled width — quote the full HM813842/HM813810 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 63.5 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 2130 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 63.5 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "An unloaded 4T-HM813842/HM813810 near 2,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 36.512 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Quote the full HM813842/HM813810 pair at ordering: the HM813842 cone also ships against sibling cups, and a cup from another reference changes the 36.512 mm assembled width and the rating.", "The 181/228 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM813842/HM813810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM813842/HM813810?", "a": "4T-HM813842/HM813810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 127 mm outside diameter and 36.512 mm assembled width T (5 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 228 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 2130 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM813842/HM813810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM813842 cone or the HM813810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 181/228 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM813842/HM813810 and a metric ISO 355 tapered bearing?", "a": "4T-HM813842/HM813810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×127×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM813842/HM813810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM813842/HM813810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM813842/HM813810 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM813842/HM813810 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM813842", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm813842-hm813810", "hm813842-hm813810", "HM813842-HM813810", "4T-HM813842-HM813810" ], "locale_variants": {} }, { "sku": "639-632", "brand": "NTN", "manufacturer_designation": "NTN 4T-639/632", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 136.525, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 215, "static_load_kN": 262, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3800, "weight_g": 2850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.5 in (63.5 mm) shaft position as 4T-639/632: cone 639, cup 632, profiled rollers and a pressed-steel cage, rated 215 kN basic dynamic and 262 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 639 identifies the cone of 63.5 mm (2.5 in) bore by catalogue lookup, and 632 fixes the 136.525 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 41.275 mm T of each 4T-639/632 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-639/632: press the 632 cup square into the 136.525 mm seat first, then bring the 639 cone (on its 63.5 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-639/632 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 2850 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (136.525×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 639/632 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never drive the 136.525 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 215/262 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-639/632; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-639/632?", "a": "4T-639/632 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 136.525 mm outside diameter and 41.275 mm assembled width T (5.375 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 215 kN, C0 262 kN, grease limiting speed 2,800 r/min, oil speed 3,800 r/min, mass about 2850 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-639/632 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 639 cone or the 632 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 215/262 kN ratings change with the cup." }, { "q": "What is the difference between 4T-639/632 and a metric ISO 355 tapered bearing?", "a": "4T-639/632 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×136.525×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-639/632 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 639/632 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-639/632 list two speeds, 2,800 and 3,800 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-639/632 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "639", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-639-632", "639-632", "4T-639-632" ], "locale_variants": {} }, { "sku": "78250-78551", "brand": "NTN", "manufacturer_designation": "NTN 4T-78250/78551", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 63.5, "D_mm": 140.03, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 190, "static_load_kN": 212, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3400, "weight_g": 2540, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-78250/78551 at 63.5 mm bore (2.5 in), 140.03 mm cup OD and 36.512 mm assembled T, with a grease limiting speed of 2,600 r/min and an oil ceiling of 3,400 r/min. Cone and cup of 4T-78250/78551 are separately stocked parts: a worn 78551 cup can be replaced against the existing 78250 cone, provided the new cup carries the identical reference — pairing across references changes the 36.512 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 36.512 mm T of each 4T-78250/78551 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 190/212 kN ratings belong to the assembled 78250+78551 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 63.5 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 63.5 mm cone by induction heating (max 120 °C) and the 140.03 mm cup with a press sleeve; at 2540 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 63.5 mm bore (140.03×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 78250/78551 reference at purchase.", "ABMA makes the 63.5×140.03 mm envelope interchangeable, not the ratings: NTN prints 190/212 kN for this execution and another make of the same number can differ in roller complement.", "Grease packs must leave free volume inside the 36.512 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,400 r/min raises temperature and destroys the setting.", "Open 4T-78250/78551 sets have no seals: a hub or gearbox needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 190/212 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-78250/78551; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-78250/78551?", "a": "4T-78250/78551 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 140.03 mm outside diameter and 36.512 mm assembled width T (5.513 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 190 kN, C0 212 kN, grease limiting speed 2,600 r/min, oil speed 3,400 r/min, mass about 2540 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-78250/78551 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 78250 cone or the 78551 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 190/212 kN ratings change with the cup." }, { "q": "What is the difference between 4T-78250/78551 and a metric ISO 355 tapered bearing?", "a": "4T-78250/78551 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 63.5×140.03×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-78250/78551 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 78250/78551 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-78250/78551 list two speeds, 2,600 and 3,400 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-78250/78551 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "78250", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-78250-78551", "78250-78551", "4T-78250-78551" ], "locale_variants": {} }, { "sku": "JLM710949-JLM710910", "brand": "NTN", "manufacturer_designation": "NTN 4T-JLM710949/JLM710910", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 105, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 94.5, "static_load_kN": 117, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4500, "weight_g": 744, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-JLM710949/JLM710910 at 65 mm bore (2.559 in), 105 mm cup OD and 24 mm assembled T, with a grease limiting speed of 3,300 r/min and an oil ceiling of 4,500 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: JLM710949 identifies the cone of 65 mm (2.559 in) bore by catalogue lookup, and JLM710910 fixes the 105 mm OD. Catalogue mass of the 4T-JLM710949/JLM710910 cone-plus-cup set is 744 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for JLM710910: within the JLM prefixed family tables the JLM710949 cone is listed against several cup options, and it is the cup that fixes the 105 mm OD and the 24 mm assembled width — quote the full JLM710949/JLM710910 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-JLM710949/JLM710910 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the 105 mm cup with a press sleeve; at 744 g a cocked ring brinells the raceway directly.", "The J-prefixed JLM710949 code belongs to a metric-envelope inch family: its 65 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Open 4T-JLM710949/JLM710910 sets have no seals: a hub or gearbox needs external sealing or the 3,300 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 24 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 24 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 94.5/117 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JLM710949/JLM710910; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JLM710949/JLM710910?", "a": "4T-JLM710949/JLM710910 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 65 mm bore (2.559 in), 105 mm outside diameter and 24 mm assembled width T (4.134 × 0.945 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 94.5 kN, C0 117 kN, grease limiting speed 3,300 r/min, oil speed 4,500 r/min, mass about 744 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JLM710949/JLM710910 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JLM710949 cone or the JLM710910 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 94.5/117 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JLM710949/JLM710910 and a metric ISO 355 tapered bearing?", "a": "4T-JLM710949/JLM710910 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 65×105×24 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JLM710949/JLM710910 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JLM710949/JLM710910 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JLM710949/JLM710910 list two speeds, 3,300 and 4,500 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JLM710949/JLM710910 at 4,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JLM710949", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jlm710949-jlm710910", "4t-jlm710949-jlm710910", "jlm710949-jlm710910", "JLM710949-JLM710910", "4T-JLM710949-JLM710910" ], "locale_variants": {} }, { "sku": "JM511946-JM511910", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM511946/JM511910", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 110, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 132, "static_load_kN": 174, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 1090, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JM511946/JM511910 is the NTN 4T catalogue entry for a 65×110×28 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Reading the designation: 4T-JM511946/JM511910 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the JM metric-envelope family lettering ties the pair to its boundary plan. Catalogue mass of the 4T-JM511946/JM511910 cone-plus-cup set is 1090 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 132/174 kN ratings belong to the assembled JM511946+JM511910 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-JM511946/JM511910 run near 3,200 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the 110 mm cup with a press sleeve; at 1090 g a cocked ring brinells the raceway directly.", "The J-prefixed JM511946 code belongs to a metric-envelope inch family: its 65 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Quote the full JM511946/JM511910 pair at ordering: the JM511946 cone also ships against sibling cups, and a cup from another reference changes the 28 mm assembled width and the rating.", "An unloaded 4T-JM511946/JM511910 near 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (28 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 132/174 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM511946/JM511910; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM511946/JM511910?", "a": "4T-JM511946/JM511910 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 65 mm bore (2.559 in), 110 mm outside diameter and 28 mm assembled width T (4.331 × 1.102 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 132 kN, C0 174 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 1090 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM511946/JM511910 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM511946 cone or the JM511910 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 132/174 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM511946/JM511910 and a metric ISO 355 tapered bearing?", "a": "4T-JM511946/JM511910 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 65×110×28 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM511946/JM511910 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM511946/JM511910 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM511946/JM511910 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM511946/JM511910 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM511946", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=186", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm511946-jm511910", "4t-jm511946-jm511910", "jm511946-jm511910", "JM511946-JM511910", "4T-JM511946-JM511910" ], "locale_variants": {} }, { "sku": "JH211749-JH211710", "brand": "NTN", "manufacturer_designation": "NTN 4T-JH211749/JH211710", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 65, "D_mm": 120, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 205, "static_load_kN": 248, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 1900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 65 mm carrying combined radial and thrust load, NTN lists 4T-JH211749/JH211710, a single-row 4T tapered roller set of 205 kN C and 248 kN C0 inside the 120 mm OD cup. Cone and cup of 4T-JH211749/JH211710 are separately stocked parts: a worn JH211710 cup can be replaced against the existing JH211749 cone, provided the new cup carries the identical reference — pairing across references changes the 39 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 39 mm T of each 4T-JH211749/JH211710 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 205/248 kN ratings belong to the assembled JH211749+JH211710 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 65 mm cone with an induction heater (max 120 °C) and press the 120 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 65 mm cone by induction heating (max 120 °C) and the 120 mm cup with a press sleeve; at 1900 g a cocked ring brinells the raceway directly.", "The J-prefixed JH211749 code belongs to a metric-envelope inch family: its 65 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Quote the full JH211749/JH211710 pair at ordering: the JH211749 cone also ships against sibling cups, and a cup from another reference changes the 39 mm assembled width and the rating.", "Grease packs must leave free volume inside the 39 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,100 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 65 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 205/248 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JH211749/JH211710; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JH211749/JH211710?", "a": "4T-JH211749/JH211710 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 65 mm bore (2.559 in), 120 mm outside diameter and 39 mm assembled width T (4.724 × 1.535 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 205 kN, C0 248 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 1900 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JH211749/JH211710 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JH211749 cone or the JH211710 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 205/248 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JH211749/JH211710 and a metric ISO 355 tapered bearing?", "a": "4T-JH211749/JH211710 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 65×120×39 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JH211749/JH211710 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JH211749/JH211710 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JH211749/JH211710 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JH211749/JH211710 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JH211749", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jh211749-jh211710", "4t-jh211749-jh211710", "jh211749-jh211710", "JH211749-JH211710", "4T-JH211749-JH211710" ], "locale_variants": {} }, { "sku": "6379-6320", "brand": "NTN", "manufacturer_designation": "NTN 4T-6379/6320", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 65.088, "D_mm": 135.755, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 310, "static_load_kN": 380, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 3710, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-6379/6320 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 6379 and cup 6320 delivered as a matched, separable pair of 65.088 mm bore and 135.755 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 6379 sits in the pure-numeric inch family. The 4.8 kN of dynamic capacity per millimetre of bore summarises the 310 kN rating over the 65.088 mm bore — sanity-check any interchange candidate against this ratio and the 53.975 mm T. Cup-side note for 6320: within the pure-numeric inch family tables the 6379 cone is listed against several cup options, and it is the cup that fixes the 135.755 mm OD and the 53.975 mm assembled width — quote the full 6379/6320 pair, never the cone alone. Mount the 65.088 mm cone with an induction heater (max 120 °C) and press the 135.755 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 65.088 mm cone by induction heating (max 120 °C) and the 135.755 mm cup with a press sleeve; at 3710 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 65.088 mm bore (135.755×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 6379/6320 reference at purchase.", "ABMA makes the 65.088×135.755 mm envelope interchangeable, not the ratings: NTN prints 310/380 kN for this execution and another make of the same number can differ in roller complement.", "Open 4T-6379/6320 sets have no seals: a hub or gearbox needs external sealing or the 2,900 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 53.975 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 310/380 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-6379/6320; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-6379/6320?", "a": "4T-6379/6320 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 65.088 mm bore (2.563 in), 135.755 mm outside diameter and 53.975 mm assembled width T (5.345 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 310 kN, C0 380 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 3710 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-6379/6320 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 6379 cone or the 6320 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 310/380 kN ratings change with the cup." }, { "q": "What is the difference between 4T-6379/6320 and a metric ISO 355 tapered bearing?", "a": "4T-6379/6320 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 65.088×135.755×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-6379/6320 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 6379/6320 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-6379/6320 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-6379/6320 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "6379-K-6320", "equiv_brand": "SKF", "level": "partial", "note": "Same 65.088×135.755×53.975 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-6379-6320", "6379-6320", "4T-6379-6320" ], "locale_variants": {} }, { "sku": "L812148-L812111", "brand": "NTN", "manufacturer_designation": "NTN 4T-L812148/L812111", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 103.213, "B_mm": 17.602, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 66.5, "static_load_kN": 78, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4400, "weight_g": 480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-L812148/L812111 belongs to the NTN inch 4T tapered roller range (light L family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-L812148/L812111 are separately stocked parts: a worn L812111 cup can be replaced against the existing L812148 cone, provided the new cup carries the identical reference — pairing across references changes the 17.602 mm assembled width and the rating. The 1.0 kN of dynamic capacity per millimetre of bore summarises the 66.5 kN rating over the 66.675 mm bore — sanity-check any interchange candidate against this ratio and the 17.602 mm T. Cup-side note for L812111: within the light L family tables the L812148 cone is listed against several cup options, and it is the cup that fixes the 103.213 mm OD and the 17.602 mm assembled width — quote the full L812148/L812111 pair, never the cone alone. Mount the 66.675 mm cone with an induction heater (max 120 °C) and press the 103.213 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 103.213 mm cup with a press sleeve; at 480 g a cocked ring brinells the raceway directly.", "The light L family at 66.675 mm bore (103.213×17.602 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L812148/L812111 reference at purchase.", "Open 4T-L812148/L812111 sets have no seals: a hub or gearbox needs external sealing or the 3,300 r/min grease figure is meaningless once water reaches the cone rib.", "Grease packs must leave free volume inside the 17.602 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,400 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 66.675 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 66.5/78 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L812148/L812111; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L812148/L812111?", "a": "4T-L812148/L812111 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 103.213 mm outside diameter and 17.602 mm assembled width T (4.064 × 0.693 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 66.5 kN, C0 78 kN, grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 480 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L812148/L812111 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L812148 cone or the L812111 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 66.5/78 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L812148/L812111 and a metric ISO 355 tapered bearing?", "a": "4T-L812148/L812111 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×103.213×17.602 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L812148/L812111 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L812148/L812111 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L812148/L812111 list two speeds, 3,300 and 4,400 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L812148/L812111 at 4,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L812148", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l812148-l812111", "l812148-l812111", "L812148-L812111", "4T-L812148-L812111" ], "locale_variants": {} }, { "sku": "29590-29520", "brand": "NTN", "manufacturer_designation": "NTN 4T-29590/29520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 107.95, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 101, "static_load_kN": 140, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 860, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-29590/29520 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 66.675×107.95×25.4 mm (assembled width T), for a shaft of about 66.675 mm (2.625 in). Cone and cup of 4T-29590/29520 are separately stocked parts: a worn 29520 cup can be replaced against the existing 29590 cone, provided the new cup carries the identical reference — pairing across references changes the 25.4 mm assembled width and the rating. Contact-angle geometry of the pure-numeric inch family gives 4T-29590/29520 its radial/axial load split — at 101/140 kN the static rating is about 1.39× C, typical of inch tapered sets proportioned for combined duty. The printed 101/140 kN ratings belong to the assembled 29590+29520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-29590/29520 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 107.95 mm cup with a press sleeve; at 860 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 66.675 mm bore (107.95×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 29590/29520 reference at purchase.", "ABMA makes the 66.675×107.95 mm envelope interchangeable, not the ratings: NTN prints 101/140 kN for this execution and another make of the same number can differ in roller complement.", "Fit selection follows the rotating ring: a rotating cone on a 66.675 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 25.4 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,300 r/min raises temperature and destroys the setting.", "The 101/140 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-29590/29520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-29590/29520?", "a": "4T-29590/29520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 107.95 mm outside diameter and 25.4 mm assembled width T (4.25 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 101 kN, C0 140 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 860 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-29590/29520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 29590 cone or the 29520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 101/140 kN ratings change with the cup." }, { "q": "What is the difference between 4T-29590/29520 and a metric ISO 355 tapered bearing?", "a": "4T-29590/29520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×107.95×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-29590/29520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 29590/29520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-29590/29520 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-29590/29520 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "29590", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-29590-29520", "29590-29520", "4T-29590-29520" ], "locale_variants": {} }, { "sku": "395A-394A-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-395A/394A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 110, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 99.5, "static_load_kN": 120, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 803, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-395A/394A at 66.675 mm bore (2.625 in), 110 mm cup OD and 22 mm assembled T, with a grease limiting speed of 3,200 r/min and an oil ceiling of 4,300 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 395A/394A without it. The 21.7 mm radial section over the 66.675 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 394A: within the pure-numeric inch family tables the 395A cone is listed against several cup options, and it is the cup that fixes the 110 mm OD and the 22 mm assembled width — quote the full 395A/394A pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-395A/394A is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 110 mm cup with a press sleeve; at 803 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 66.675 mm bore (110×22 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 395A/394A reference at purchase.", "Inch and metric bores collide on paper — 66.675 mm is 2.625 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Quote the full 395A/394A pair at ordering: the 395A cone also ships against sibling cups, and a cup from another reference changes the 22 mm assembled width and the rating.", "Quote the full 395A/394A pair at ordering: the 395A cone also ships against sibling cups, and a cup from another reference changes the 22 mm assembled width and the rating.", "The 99.5/120 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-395A/394A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-395A/394A?", "a": "4T-395A/394A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 110 mm outside diameter and 22 mm assembled width T (4.331 × 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 99.5 kN, C0 120 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 803 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-395A/394A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 395A cone or the 394A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 99.5/120 kN ratings change with the cup." }, { "q": "What is the difference between 4T-395A/394A and a metric ISO 355 tapered bearing?", "a": "4T-395A/394A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×110×22 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-395A/394A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 395A/394A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-395A/394A list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-395A/394A at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "395A-394A", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "395a-394a", "4t-395a-394a", "395A-394A", "4T-395A-394A", "395A-394A-NTN" ], "locale_variants": {} }, { "sku": "39590-39520-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-39590/39520", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 195, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-39590/39520 at 66.675 mm bore (2.625 in), 112.712 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 3,200 r/min and an oil ceiling of 4,200 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 39590/39520 without it. Selection: C 153 kN against C0 195 kN gives a C0/C ratio of 1.27 for the 66.675 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 153/195 kN ratings belong to the assembled 39590+39520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-39590/39520; reverse the fit logic when the cup rotates.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 1280 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 66.675 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 39590/39520 reference at purchase.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 66.675 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 66.675 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 153/195 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-39590/39520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-39590/39520?", "a": "4T-39590/39520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 195 kN, grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1280 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-39590/39520 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 39590 cone or the 39520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/195 kN ratings change with the cup." }, { "q": "What is the difference between 4T-39590/39520 and a metric ISO 355 tapered bearing?", "a": "4T-39590/39520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-39590/39520 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 39590/39520 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-39590/39520 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-39590/39520 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "39590-39520", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "39590-39528", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-39590-39520", "39590-39520", "4T-39590-39520", "39590-39520-NTN" ], "locale_variants": {} }, { "sku": "3984-3925", "brand": "NTN", "manufacturer_designation": "NTN 4T-3984/3925", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 132, "static_load_kN": 174, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 1190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3984/3925 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 66.675×112.712×30.162 mm (assembled width T), for a shaft of about 66.675 mm (2.625 in). Cone and cup of 4T-3984/3925 are separately stocked parts: a worn 3925 cup can be replaced against the existing 3984 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 3,200 r/min is the mechanical ceiling for 4T-3984/3925, oil 4,300 r/min with circulating oil — a 1,100 r/min margin at this size. Cup-side note for 3925: within the pure-numeric inch family tables the 3984 cone is listed against several cup options, and it is the cup that fixes the 112.712 mm OD and the 30.162 mm assembled width — quote the full 3984/3925 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-3984/3925 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 1190 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 66.675 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3984/3925 reference at purchase.", "Quote the full 3984/3925 pair at ordering: the 3984 cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,300 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 66.675 mm is 2.625 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 132/174 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3984/3925; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3984/3925?", "a": "4T-3984/3925 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 132 kN, C0 174 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 1190 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3984/3925 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3984 cone or the 3925 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 132/174 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3984/3925 and a metric ISO 355 tapered bearing?", "a": "4T-3984/3925 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3984/3925 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3984/3925 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3984/3925 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3984/3925 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3984-3920", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3984-3925", "3984-3925", "4T-3984-3925" ], "locale_variants": {} }, { "sku": "3994-3920", "brand": "NTN", "manufacturer_designation": "NTN 4T-3994/3920", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 112.712, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 132, "static_load_kN": 174, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 1180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-3994/3920 is the NTN 4T catalogue entry for a 66.675×112.712×30.162 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 3994 sits in the pure-numeric inch family. Grease relubrication at the 3,200 r/min limiting speed targets the cone-rib contact; sustaining 4,300 r/min needs an oil supply directed at the large roller ends. The printed 132/174 kN ratings belong to the assembled 3994+3920 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-3994/3920, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 1180 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 66.675 mm bore (112.712×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3994/3920 reference at purchase.", "An unloaded 4T-3994/3920 near 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "An unloaded 4T-3994/3920 near 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 132/174 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3994/3920; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-3994/3920?", "a": "4T-3994/3920 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 112.712 mm outside diameter and 30.162 mm assembled width T (4.437 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 132 kN, C0 174 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 1180 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-3994/3920 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 3994 cone or the 3920 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 132/174 kN ratings change with the cup." }, { "q": "What is the difference between 4T-3994/3920 and a metric ISO 355 tapered bearing?", "a": "4T-3994/3920 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×112.712×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-3994/3920 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 3994/3920 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-3994/3920 list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-3994/3920 at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "3994", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-3994-3920", "3994-3920", "4T-3994-3920" ], "locale_variants": {} }, { "sku": "HM212049-HM212010", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM212049/HM212010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 122.238, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 208, "static_load_kN": 244, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 1840, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM212049/HM212010 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote HM212049/HM212010 without it. Catalogue mass of the 4T-HM212049/HM212010 cone-plus-cup set is 1840 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 208/244 kN ratings belong to the assembled HM212049+HM212010 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the HM212049 cone and HM212010 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 122.238 mm cup with a press sleeve; at 1840 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 66.675 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Never drive the 122.238 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Shaft and housing fillets must clear the ring chamfers of HM212049 and HM212010; use undercut shoulders so the rings seat on the face, not on a radius.", "Open 4T-HM212049/HM212010 sets have no seals: a hub or gearbox needs external sealing or the 3,100 r/min grease figure is meaningless once water reaches the cone rib.", "The 208/244 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM212049/HM212010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM212049/HM212010?", "a": "4T-HM212049/HM212010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 122.238 mm outside diameter and 38.1 mm assembled width T (4.813 × 1.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 208 kN, C0 244 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 1840 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM212049/HM212010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM212049 cone or the HM212010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 208/244 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM212049/HM212010 and a metric ISO 355 tapered bearing?", "a": "4T-HM212049/HM212010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×122.238×38.1 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM212049/HM212010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM212049/HM212010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM212049/HM212010 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM212049/HM212010 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM212049-011", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm212049-hm212010", "hm212049-hm212010", "HM212049-HM212010", "4T-HM212049-HM212010" ], "locale_variants": {} }, { "sku": "560-552A", "brand": "NTN", "manufacturer_designation": "NTN 4T-560/552A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 123.825, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 175, "static_load_kN": 216, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4100, "weight_g": 1900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-560/552A at 66.675 mm bore (2.625 in), 123.825 mm cup OD and 38.1 mm assembled T, with a grease limiting speed of 3,000 r/min and an oil ceiling of 4,100 r/min. Cone and cup of 4T-560/552A are separately stocked parts: a worn 552A cup can be replaced against the existing 560 cone, provided the new cup carries the identical reference — pairing across references changes the 38.1 mm assembled width and the rating. The 2.6 kN of dynamic capacity per millimetre of bore summarises the 175 kN rating over the 66.675 mm bore — sanity-check any interchange candidate against this ratio and the 38.1 mm T. Cup-side note for 552A: within the pure-numeric inch family tables the 560 cone is listed against several cup options, and it is the cup that fixes the 123.825 mm OD and the 38.1 mm assembled width — quote the full 560/552A pair, never the cone alone. Mount the 66.675 mm cone with an induction heater (max 120 °C) and press the 123.825 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 123.825 mm cup with a press sleeve; at 1900 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 66.675 mm bore (123.825×38.1 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 560/552A reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 66.675 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 38.1 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,100 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 66.675 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 175/216 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-560/552A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-560/552A?", "a": "4T-560/552A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 123.825 mm outside diameter and 38.1 mm assembled width T (4.875 × 1.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 175 kN, C0 216 kN, grease limiting speed 3,000 r/min, oil speed 4,100 r/min, mass about 1900 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-560/552A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 560 cone or the 552A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 175/216 kN ratings change with the cup." }, { "q": "What is the difference between 4T-560/552A and a metric ISO 355 tapered bearing?", "a": "4T-560/552A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×123.825×38.1 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-560/552A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 560/552A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-560/552A list two speeds, 3,000 and 4,100 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-560/552A at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "560", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-560-552a", "560-552a", "560-552A", "4T-560-552A" ], "locale_variants": {} }, { "sku": "HM813844-HM813810", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM813844/HM813810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 127, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 181, "static_load_kN": 228, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 2030, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 66.675 mm carrying combined radial and thrust load, NTN lists 4T-HM813844/HM813810, a single-row 4T tapered roller set of 181 kN C and 228 kN C0 inside the 127 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote HM813844/HM813810 without it. Catalogue mass of the 4T-HM813844/HM813810 cone-plus-cup set is 2030 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for HM813810: within the heavy-medium HM family tables the HM813844 cone is listed against several cup options, and it is the cup that fixes the 127 mm OD and the 36.512 mm assembled width — quote the full HM813844/HM813810 pair, never the cone alone. Fillet radii must clear the chamfers of the HM813844 cone and HM813810 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 2030 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 66.675 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Shaft and housing fillets must clear the ring chamfers of HM813844 and HM813810; use undercut shoulders so the rings seat on the face, not on a radius.", "Never drive the 127 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 181/228 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM813844/HM813810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM813844/HM813810?", "a": "4T-HM813844/HM813810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 127 mm outside diameter and 36.512 mm assembled width T (5 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 228 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 2030 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM813844/HM813810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM813844 cone or the HM813810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 181/228 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM813844/HM813810 and a metric ISO 355 tapered bearing?", "a": "4T-HM813844/HM813810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×127×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM813844/HM813810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM813844/HM813810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM813844/HM813810 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM813844/HM813810 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM813844", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm813844-hm813810", "hm813844-hm813810", "HM813844-HM813810", "4T-HM813844-HM813810" ], "locale_variants": {} }, { "sku": "641-633", "brand": "NTN", "manufacturer_designation": "NTN 4T-641/633", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 130.175, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 215, "static_load_kN": 262, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3800, "weight_g": 2410, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-641/633 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 641 and cup 633 delivered as a matched, separable pair of 66.675 mm bore and 130.175 mm outside diameter. Reading the designation: 4T-641/633 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 31.8 mm radial section over the 66.675 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 633: within the pure-numeric inch family tables the 641 cone is listed against several cup options, and it is the cup that fixes the 130.175 mm OD and the 41.275 mm assembled width — quote the full 641/633 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-641/633 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 130.175 mm cup with a press sleeve; at 2410 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 66.675 mm bore (130.175×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 641/633 reference at purchase.", "Grease packs must leave free volume inside the 41.275 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,800 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of 641 and 633; use undercut shoulders so the rings seat on the face, not on a radius.", "ABMA makes the 66.675×130.175 mm envelope interchangeable, not the ratings: NTN prints 215/262 kN for this execution and another make of the same number can differ in roller complement.", "The 215/262 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-641/633; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-641/633?", "a": "4T-641/633 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 130.175 mm outside diameter and 41.275 mm assembled width T (5.125 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 215 kN, C0 262 kN, grease limiting speed 2,800 r/min, oil speed 3,800 r/min, mass about 2410 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-641/633 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 641 cone or the 633 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 215/262 kN ratings change with the cup." }, { "q": "What is the difference between 4T-641/633 and a metric ISO 355 tapered bearing?", "a": "4T-641/633 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×130.175×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-641/633 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 641/633 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-641/633 list two speeds, 2,800 and 3,800 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-641/633 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "641-632", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-641 paired with a different cup (632): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-641-633", "641-633", "4T-641-633" ], "locale_variants": {} }, { "sku": "6386-6320", "brand": "NTN", "manufacturer_designation": "NTN 4T-6386/6320", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 135.755, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 310, "static_load_kN": 380, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 3640, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-6386/6320 at 66.675 mm bore (2.625 in), 135.755 mm cup OD and 53.975 mm assembled T, with a grease limiting speed of 2,900 r/min and an oil ceiling of 3,800 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 6386/6320 without it. Contact-angle geometry of the pure-numeric inch family gives 4T-6386/6320 its radial/axial load split — at 310/380 kN the static rating is about 1.23× C, typical of inch tapered sets proportioned for combined duty. The printed 310/380 kN ratings belong to the assembled 6386+6320 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 66.675 mm cone with an induction heater (max 120 °C) and press the 135.755 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 135.755 mm cup with a press sleeve; at 3640 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 66.675 mm bore (135.755×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 6386/6320 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 6386 and 6320; use undercut shoulders so the rings seat on the face, not on a radius.", "Never drive the 135.755 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Open 4T-6386/6320 sets have no seals: a hub or gearbox needs external sealing or the 2,900 r/min grease figure is meaningless once water reaches the cone rib.", "The 310/380 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-6386/6320; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-6386/6320?", "a": "4T-6386/6320 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 135.755 mm outside diameter and 53.975 mm assembled width T (5.345 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 310 kN, C0 380 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 3640 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-6386/6320 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 6386 cone or the 6320 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 310/380 kN ratings change with the cup." }, { "q": "What is the difference between 4T-6386/6320 and a metric ISO 355 tapered bearing?", "a": "4T-6386/6320 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×135.755×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-6386/6320 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 6386/6320 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-6386/6320 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-6386/6320 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "6386-K-6320", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-6386-6320", "6386-6320", "4T-6386-6320" ], "locale_variants": {} }, { "sku": "641-632", "brand": "NTN", "manufacturer_designation": "NTN 4T-641/632", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 136.525, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 215, "static_load_kN": 262, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3800, "weight_g": 2750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-641/632 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 66.675×136.525×41.275 mm (assembled width T), for a shaft of about 66.675 mm (2.625 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 641/632 without it. Grease relubrication at the 2,800 r/min limiting speed targets the cone-rib contact; sustaining 3,800 r/min needs an oil supply directed at the large roller ends. Cup-side note for 632: within the pure-numeric inch family tables the 641 cone is listed against several cup options, and it is the cup that fixes the 136.525 mm OD and the 41.275 mm assembled width — quote the full 641/632 pair, never the cone alone. Running clearance of 4T-641/632 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 2750 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 66.675 mm bore (136.525×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 641/632 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Grease packs must leave free volume inside the 41.275 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,800 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of 641 and 632; use undercut shoulders so the rings seat on the face, not on a radius.", "The 215/262 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-641/632; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-641/632?", "a": "4T-641/632 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 136.525 mm outside diameter and 41.275 mm assembled width T (5.375 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 215 kN, C0 262 kN, grease limiting speed 2,800 r/min, oil speed 3,800 r/min, mass about 2750 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-641/632 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 641 cone or the 632 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 215/262 kN ratings change with the cup." }, { "q": "What is the difference between 4T-641/632 and a metric ISO 355 tapered bearing?", "a": "4T-641/632 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×136.525×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-641/632 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 641/632 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-641/632 list two speeds, 2,800 and 3,800 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-641/632 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "641-633", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-641 paired with a different cup (633): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-641-632", "641-632", "4T-641-632" ], "locale_variants": {} }, { "sku": "H414242-H414210", "brand": "NTN", "manufacturer_designation": "NTN 4T-H414242/H414210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 66.675, "D_mm": 136.525, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 251, "static_load_kN": 293, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3700, "weight_g": 2750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.625 in (66.675 mm) shaft position as 4T-H414242/H414210: cone H414242, cup H414210, profiled rollers and a pressed-steel cage, rated 251 kN basic dynamic and 293 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: H414242 identifies the cone of 66.675 mm (2.625 in) bore by catalogue lookup, and H414210 fixes the 136.525 mm OD. The 3.8 kN of dynamic capacity per millimetre of bore summarises the 251 kN rating over the 66.675 mm bore — sanity-check any interchange candidate against this ratio and the 41.275 mm T. Cup-side note for H414210: within the heavy H family tables the H414242 cone is listed against several cup options, and it is the cup that fixes the 136.525 mm OD and the 41.275 mm assembled width — quote the full H414242/H414210 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-H414242/H414210 run near 2,700 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 66.675 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 2750 g a cocked ring brinells the raceway directly.", "The heavy H family at 66.675 mm bore (136.525×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full H414242/H414210 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Never drive the 136.525 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Quote the full H414242/H414210 pair at ordering: the H414242 cone also ships against sibling cups, and a cup from another reference changes the 41.275 mm assembled width and the rating.", "The 251/293 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-H414242/H414210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-H414242/H414210?", "a": "4T-H414242/H414210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 136.525 mm outside diameter and 41.275 mm assembled width T (5.375 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 251 kN, C0 293 kN, grease limiting speed 2,700 r/min, oil speed 3,700 r/min, mass about 2750 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-H414242/H414210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the H414242 cone or the H414210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 251/293 kN ratings change with the cup." }, { "q": "What is the difference between 4T-H414242/H414210 and a metric ISO 355 tapered bearing?", "a": "4T-H414242/H414210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 66.675×136.525×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-H414242/H414210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare H414242/H414210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-H414242/H414210 list two speeds, 2,700 and 3,700 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-H414242/H414210 at 3,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "H414242", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-h414242-h414210", "h414242-h414210", "H414242-H414210", "4T-H414242-H414210" ], "locale_variants": {} }, { "sku": "399A-394A", "brand": "NTN", "manufacturer_designation": "NTN 4T-399A/394A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 68.262, "D_mm": 110, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 99.5, "static_load_kN": 120, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4300, "weight_g": 772, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-399A/394A at 68.262 mm bore (2.687 in), 110 mm cup OD and 22 mm assembled T, with a grease limiting speed of 3,200 r/min and an oil ceiling of 4,300 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 399A sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 22 mm T of each 4T-399A/394A enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 394A: within the pure-numeric inch family tables the 399A cone is listed against several cup options, and it is the cup that fixes the 110 mm OD and the 22 mm assembled width — quote the full 399A/394A pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-399A/394A sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 68.262 mm cone by induction heating (max 120 °C) and the 110 mm cup with a press sleeve; at 772 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 68.262 mm bore (110×22 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 399A/394A reference at purchase.", "Inch and metric bores collide on paper — 68.262 mm is 2.687 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Never drive the 110 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 68.262×110 mm envelope interchangeable, not the ratings: NTN prints 99.5/120 kN for this execution and another make of the same number can differ in roller complement.", "The 99.5/120 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-399A/394A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-399A/394A?", "a": "4T-399A/394A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 68.262 mm bore (2.687 in), 110 mm outside diameter and 22 mm assembled width T (4.331 × 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 99.5 kN, C0 120 kN, grease limiting speed 3,200 r/min, oil speed 4,300 r/min, mass about 772 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-399A/394A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 399A cone or the 394A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 99.5/120 kN ratings change with the cup." }, { "q": "What is the difference between 4T-399A/394A and a metric ISO 355 tapered bearing?", "a": "4T-399A/394A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 68.262×110×22 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-399A/394A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 399A/394A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-399A/394A list two speeds, 3,200 and 4,300 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-399A/394A at 4,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "399A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "399a-394a", "4t-399a-394a", "399A-394A", "4T-399A-394A" ], "locale_variants": {} }, { "sku": "480-472", "brand": "NTN", "manufacturer_designation": "NTN 4T-480/472", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 68.262, "D_mm": 120, "B_mm": 29.794, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 142, "static_load_kN": 177, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 68.262 mm carrying combined radial and thrust load, NTN lists 4T-480/472, a single-row 4T tapered roller set of 142 kN C and 177 kN C0 inside the 120 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 480/472 without it. The 2.1 kN of dynamic capacity per millimetre of bore summarises the 142 kN rating over the 68.262 mm bore — sanity-check any interchange candidate against this ratio and the 29.794 mm T. Housing fitment sequence for 4T-480/472: press the 472 cup square into the 120 mm seat first, then bring the 480 cone (on its 68.262 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-480/472; reverse the fit logic when the cup rotates.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 68.262 mm cone by induction heating (max 120 °C) and the 120 mm cup with a press sleeve; at 1130 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 68.262 mm bore (120×29.794 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 480/472 reference at purchase.", "Do not confuse T (29.794 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Shaft and housing fillets must clear the ring chamfers of 480 and 472; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-480/472 near 3,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 142/177 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-480/472; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-480/472?", "a": "4T-480/472 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 68.262 mm bore (2.687 in), 120 mm outside diameter and 29.794 mm assembled width T (4.724 × 1.173 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 142 kN, C0 177 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1130 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-480/472 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 480 cone or the 472 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 142/177 kN ratings change with the cup." }, { "q": "What is the difference between 4T-480/472 and a metric ISO 355 tapered bearing?", "a": "4T-480/472 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 68.262×120×29.794 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-480/472 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 480/472 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-480/472 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-480/472 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "480", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-480-472", "480-472", "4T-480-472" ], "locale_variants": {} }, { "sku": "560S-552A", "brand": "NTN", "manufacturer_designation": "NTN 4T-560S/552A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 68.262, "D_mm": 123.825, "B_mm": 38.1, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 175, "static_load_kN": 216, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4100, "weight_g": 1870, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.687 in (68.262 mm) shaft position as 4T-560S/552A: cone 560S, cup 552A, profiled rollers and a pressed-steel cage, rated 175 kN basic dynamic and 216 kN static. Reading the designation: 4T-560S/552A follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 27.8 mm radial section over the 68.262 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 552A: within the pure-numeric inch family tables the 560S cone is listed against several cup options, and it is the cup that fixes the 123.825 mm OD and the 38.1 mm assembled width — quote the full 560S/552A pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-560S/552A run near 3,000 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 68.262 mm cone by induction heating (max 120 °C) and the 123.825 mm cup with a press sleeve; at 1870 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 68.262 mm bore (123.825×38.1 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 560S/552A reference at purchase.", "Inch and metric bores collide on paper — 68.262 mm is 2.687 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-560S/552A sets have no seals: a hub or gearbox needs external sealing or the 3,000 r/min grease figure is meaningless once water reaches the cone rib.", "Open 4T-560S/552A sets have no seals: a hub or gearbox needs external sealing or the 3,000 r/min grease figure is meaningless once water reaches the cone rib.", "The 175/216 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-560S/552A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-560S/552A?", "a": "4T-560S/552A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 68.262 mm bore (2.687 in), 123.825 mm outside diameter and 38.1 mm assembled width T (4.875 × 1.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 175 kN, C0 216 kN, grease limiting speed 3,000 r/min, oil speed 4,100 r/min, mass about 1870 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-560S/552A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 560S cone or the 552A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 175/216 kN ratings change with the cup." }, { "q": "What is the difference between 4T-560S/552A and a metric ISO 355 tapered bearing?", "a": "4T-560S/552A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 68.262×123.825×38.1 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-560S/552A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 560S/552A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-560S/552A list two speeds, 3,000 and 4,100 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-560S/552A at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "560S", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-560s-552a", "560s-552a", "560S-552A", "4T-560S-552A" ], "locale_variants": {} }, { "sku": "H414245-H414210", "brand": "NTN", "manufacturer_designation": "NTN 4T-H414245/H414210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 68.262, "D_mm": 136.525, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 251, "static_load_kN": 293, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3700, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-H414245/H414210 belongs to the NTN inch 4T tapered roller range (heavy H family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — H414245 sits in the heavy H family. The 3.7 kN of dynamic capacity per millimetre of bore summarises the 251 kN rating over the 68.262 mm bore — sanity-check any interchange candidate against this ratio and the 41.275 mm T. The printed 251/293 kN ratings belong to the assembled H414245+H414210 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-H414245/H414210 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 68.262 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 2700 g a cocked ring brinells the raceway directly.", "The heavy H family at 68.262 mm bore (136.525×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full H414245/H414210 reference at purchase.", "Open 4T-H414245/H414210 sets have no seals: a hub or gearbox needs external sealing or the 2,700 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 68.262×136.525 mm envelope interchangeable, not the ratings: NTN prints 251/293 kN for this execution and another make of the same number can differ in roller complement.", "Open 4T-H414245/H414210 sets have no seals: a hub or gearbox needs external sealing or the 2,700 r/min grease figure is meaningless once water reaches the cone rib.", "The 251/293 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-H414245/H414210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-H414245/H414210?", "a": "4T-H414245/H414210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 68.262 mm bore (2.687 in), 136.525 mm outside diameter and 41.275 mm assembled width T (5.375 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 251 kN, C0 293 kN, grease limiting speed 2,700 r/min, oil speed 3,700 r/min, mass about 2700 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-H414245/H414210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the H414245 cone or the H414210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 251/293 kN ratings change with the cup." }, { "q": "What is the difference between 4T-H414245/H414210 and a metric ISO 355 tapered bearing?", "a": "4T-H414245/H414210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 68.262×136.525×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-H414245/H414210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare H414245/H414210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-H414245/H414210 list two speeds, 2,700 and 3,700 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-H414245/H414210 at 3,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "H414245", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-h414245-h414210", "h414245-h414210", "H414245-H414210", "4T-H414245-H414210" ], "locale_variants": {} }, { "sku": "H715343-H715311", "brand": "NTN", "manufacturer_designation": "NTN 4T-H715343/H715311", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 68.262, "D_mm": 136.525, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 248, "static_load_kN": 355, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 3230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.687 in (68.262 mm) shaft position as 4T-H715343/H715311: cone H715343, cup H715311, profiled rollers and a pressed-steel cage, rated 248 kN basic dynamic and 355 kN static. Cone and cup of 4T-H715343/H715311 are separately stocked parts: a worn H715311 cup can be replaced against the existing H715343 cone, provided the new cup carries the identical reference — pairing across references changes the 46.038 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 46.038 mm T of each 4T-H715343/H715311 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 248/355 kN ratings belong to the assembled H715343+H715311 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-H715343/H715311 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 68.262 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 3230 g a cocked ring brinells the raceway directly.", "The heavy H family at 68.262 mm bore (136.525×46.038 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full H715343/H715311 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of H715343 and H715311; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of H715343 and H715311; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 68.262 mm is 2.687 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 248/355 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-H715343/H715311; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-H715343/H715311?", "a": "4T-H715343/H715311 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 68.262 mm bore (2.687 in), 136.525 mm outside diameter and 46.038 mm assembled width T (5.375 × 1.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 248 kN, C0 355 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 3230 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-H715343/H715311 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the H715343 cone or the H715311 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 248/355 kN ratings change with the cup." }, { "q": "What is the difference between 4T-H715343/H715311 and a metric ISO 355 tapered bearing?", "a": "4T-H715343/H715311 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 68.262×136.525×46.038 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-H715343/H715311 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare H715343/H715311 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-H715343/H715311 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-H715343/H715311 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "H715343", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-h715343-h715311", "h715343-h715311", "H715343-H715311", "4T-H715343-H715311" ], "locale_variants": {} }, { "sku": "29675-29620-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-29675/29620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 112.712, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 106, "static_load_kN": 151, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-29675/29620 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 29675/29620 without it. Catalogue mass of the 4T-29675/29620 cone-plus-cup set is 950 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 29620: within the pure-numeric inch family tables the 29675 cone is listed against several cup options, and it is the cup that fixes the 112.712 mm OD and the 25.4 mm assembled width — quote the full 29675/29620 pair, never the cone alone. Running clearance of 4T-29675/29620 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 69.85 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 950 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 69.85 mm bore (112.712×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 29675/29620 reference at purchase.", "Inch and metric bores collide on paper — 69.85 mm is 2.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-29675/29620 sets have no seals: a hub or gearbox needs external sealing or the 3,100 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 69.85×112.712 mm envelope interchangeable, not the ratings: NTN prints 106/151 kN for this execution and another make of the same number can differ in roller complement.", "The 106/151 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-29675/29620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-29675/29620?", "a": "4T-29675/29620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 69.85 mm bore (2.75 in), 112.712 mm outside diameter and 25.4 mm assembled width T (4.437 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 106 kN, C0 151 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 950 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-29675/29620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 29675 cone or the 29620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 106/151 kN ratings change with the cup." }, { "q": "What is the difference between 4T-29675/29620 and a metric ISO 355 tapered bearing?", "a": "4T-29675/29620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 69.85×112.712×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-29675/29620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 29675/29620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-29675/29620 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-29675/29620 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "29675-29620", "equiv_brand": "SKF", "level": "partial", "note": "Same 69.85×112.712×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "29675-29630", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-29675 paired with a different cup (29630): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-29675-29620", "29675-29620", "4T-29675-29620", "29675-29620-NTN" ], "locale_variants": {} }, { "sku": "33275-33462", "brand": "NTN", "manufacturer_designation": "NTN 4T-33275/33462", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 117.475, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 129, "static_load_kN": 175, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 69.85 mm carrying combined radial and thrust load, NTN lists 4T-33275/33462, a single-row 4T tapered roller set of 129 kN C and 175 kN C0 inside the 117.475 mm OD cup. Cone and cup of 4T-33275/33462 are separately stocked parts: a worn 33462 cup can be replaced against the existing 33275 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Grease relubrication at the 3,000 r/min limiting speed targets the cone-rib contact; sustaining 4,000 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-33275/33462: press the 33462 cup square into the 117.475 mm seat first, then bring the 33275 cone (on its 69.85 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-33275/33462, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 69.85 mm cone by induction heating (max 120 °C) and the 117.475 mm cup with a press sleeve; at 1280 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 69.85 mm bore (117.475×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 33275/33462 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 69.85 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 69.85×117.475 mm envelope interchangeable, not the ratings: NTN prints 129/175 kN for this execution and another make of the same number can differ in roller complement.", "Fit selection follows the rotating ring: a rotating cone on a 69.85 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 129/175 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-33275/33462; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-33275/33462?", "a": "4T-33275/33462 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 69.85 mm bore (2.75 in), 117.475 mm outside diameter and 30.162 mm assembled width T (4.625 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 129 kN, C0 175 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1280 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-33275/33462 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 33275 cone or the 33462 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 129/175 kN ratings change with the cup." }, { "q": "What is the difference between 4T-33275/33462 and a metric ISO 355 tapered bearing?", "a": "4T-33275/33462 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 69.85×117.475×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-33275/33462 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 33275/33462 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-33275/33462 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-33275/33462 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "33275", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-33275-33462", "33275-33462", "4T-33275-33462" ], "locale_variants": {} }, { "sku": "47487-47420-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-47487/47420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 120, "B_mm": 32.545, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 163, "static_load_kN": 214, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1630, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-47487/47420 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 47487 and cup 47420 delivered as a matched, separable pair of 69.85 mm bore and 120 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 47487 sits in the pure-numeric inch family. Catalogue mass of the 4T-47487/47420 cone-plus-cup set is 1630 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 163/214 kN ratings belong to the assembled 47487+47420 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-47487/47420 run near 3,000 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 69.85 mm cone by induction heating (max 120 °C) and the 120 mm cup with a press sleeve; at 1630 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 69.85 mm bore (120×32.545 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 47487/47420 reference at purchase.", "Quote the full 47487/47420 pair at ordering: the 47487 cone also ships against sibling cups, and a cup from another reference changes the 32.545 mm assembled width and the rating.", "An unloaded 4T-47487/47420 near 3,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (32.545 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 163/214 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-47487/47420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-47487/47420?", "a": "4T-47487/47420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 69.85 mm bore (2.75 in), 120 mm outside diameter and 32.545 mm assembled width T (4.724 × 1.281 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 163 kN, C0 214 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1630 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-47487/47420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 47487 cone or the 47420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 163/214 kN ratings change with the cup." }, { "q": "What is the difference between 4T-47487/47420 and a metric ISO 355 tapered bearing?", "a": "4T-47487/47420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 69.85×120×32.545 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-47487/47420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 47487/47420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-47487/47420 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-47487/47420 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "47487-47420", "equiv_brand": "SKF", "level": "partial", "note": "Same 69.85×120×32.545 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "47487-47420A", "equiv_brand": "SKF", "level": "partial", "note": "Same 69.85×120×32.545 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-47487-47420", "47487-47420", "4T-47487-47420", "47487-47420-NTN" ], "locale_variants": {} }, { "sku": "482-472-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-482/472", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 120, "B_mm": 29.794, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 142, "static_load_kN": 177, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-482/472 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-482/472 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 69.85×120×29.794 mm converts to 2.75 × 4.724 × 1.173 in; the ABMA envelope swaps with like-numbered inch parts but the 142/177 kN ratings are NTN-specific. The printed 142/177 kN ratings belong to the assembled 482+472 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 69.85 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 69.85 mm cone by induction heating (max 120 °C) and the 120 mm cup with a press sleeve; at 1330 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 69.85 mm bore (120×29.794 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 482/472 reference at purchase.", "An unloaded 4T-482/472 near 3,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "ABMA makes the 69.85×120 mm envelope interchangeable, not the ratings: NTN prints 142/177 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 69.85×120 mm envelope interchangeable, not the ratings: NTN prints 142/177 kN for this execution and another make of the same number can differ in roller complement.", "The 142/177 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-482/472; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-482/472?", "a": "4T-482/472 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 69.85 mm bore (2.75 in), 120 mm outside diameter and 29.794 mm assembled width T (4.724 × 1.173 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 142 kN, C0 177 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1330 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-482/472 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 482 cone or the 472 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 142/177 kN ratings change with the cup." }, { "q": "What is the difference between 4T-482/472 and a metric ISO 355 tapered bearing?", "a": "4T-482/472 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 69.85×120×29.794 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-482/472 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 482/472 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-482/472 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-482/472 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "482-472", "equiv_brand": "SKF", "level": "partial", "note": "Same 69.85×120×29.794 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-482-472", "482-472", "4T-482-472", "482-472-NTN" ], "locale_variants": {} }, { "sku": "29675-29630", "brand": "NTN", "manufacturer_designation": "NTN 4T-29675/29630", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 120.65, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 106, "static_load_kN": 151, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 1170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-29675/29630 at 69.85 mm bore (2.75 in), 120.65 mm cup OD and 25.4 mm assembled T, with a grease limiting speed of 3,100 r/min and an oil ceiling of 4,100 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 29675 identifies the cone of 69.85 mm (2.75 in) bore by catalogue lookup, and 29630 fixes the 120.65 mm OD. The 1.5 kN of dynamic capacity per millimetre of bore summarises the 106 kN rating over the 69.85 mm bore — sanity-check any interchange candidate against this ratio and the 25.4 mm T. The printed 106/151 kN ratings belong to the assembled 29675+29630 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-29675/29630, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 69.85 mm cone by induction heating (max 120 °C) and the 120.65 mm cup with a press sleeve; at 1170 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 69.85 mm bore (120.65×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 29675/29630 reference at purchase.", "Inch and metric bores collide on paper — 69.85 mm is 2.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 25.4 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,100 r/min raises temperature and destroys the setting.", "Grease packs must leave free volume inside the 25.4 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,100 r/min raises temperature and destroys the setting.", "The 106/151 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-29675/29630; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-29675/29630?", "a": "4T-29675/29630 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 69.85 mm bore (2.75 in), 120.65 mm outside diameter and 25.4 mm assembled width T (4.75 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 106 kN, C0 151 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 1170 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-29675/29630 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 29675 cone or the 29630 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 106/151 kN ratings change with the cup." }, { "q": "What is the difference between 4T-29675/29630 and a metric ISO 355 tapered bearing?", "a": "4T-29675/29630 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 69.85×120.65×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-29675/29630 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 29675/29630 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-29675/29630 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-29675/29630 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "29675-29620", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "29675-29620-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-29675 paired with a different cup (29620): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-29675-29630", "29675-29630", "4T-29675-29630" ], "locale_variants": {} }, { "sku": "566-563-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-566/563", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 127, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 181, "static_load_kN": 229, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 1910, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-566/563 at 69.85 mm bore (2.75 in), 127 mm cup OD and 36.512 mm assembled T, with a grease limiting speed of 2,900 r/min and an oil ceiling of 3,800 r/min. Cone and cup of 4T-566/563 are separately stocked parts: a worn 563 cup can be replaced against the existing 566 cone, provided the new cup carries the identical reference — pairing across references changes the 36.512 mm assembled width and the rating. The 2.6 kN of dynamic capacity per millimetre of bore summarises the 181 kN rating over the 69.85 mm bore — sanity-check any interchange candidate against this ratio and the 36.512 mm T. Housing fitment sequence for 4T-566/563: press the 563 cup square into the 127 mm seat first, then bring the 566 cone (on its 69.85 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-566/563 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 69.85 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 1910 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 69.85 mm bore (127×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 566/563 reference at purchase.", "ABMA makes the 69.85×127 mm envelope interchangeable, not the ratings: NTN prints 181/229 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 566/563 pair at ordering: the 566 cone also ships against sibling cups, and a cup from another reference changes the 36.512 mm assembled width and the rating.", "Quote the full 566/563 pair at ordering: the 566 cone also ships against sibling cups, and a cup from another reference changes the 36.512 mm assembled width and the rating.", "The 181/229 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-566/563; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-566/563?", "a": "4T-566/563 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 69.85 mm bore (2.75 in), 127 mm outside diameter and 36.512 mm assembled width T (5 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 229 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 1910 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-566/563 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 566 cone or the 563 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 181/229 kN ratings change with the cup." }, { "q": "What is the difference between 4T-566/563 and a metric ISO 355 tapered bearing?", "a": "4T-566/563 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 69.85×127×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-566/563 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 566/563 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-566/563 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-566/563 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "566-563", "equiv_brand": "SKF", "level": "partial", "note": "Same 69.85×127×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-566-563", "566-563", "4T-566-563", "566-563-NTN" ], "locale_variants": {} }, { "sku": "643-632", "brand": "NTN", "manufacturer_designation": "NTN 4T-643/632", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 136.525, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 215, "static_load_kN": 262, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3800, "weight_g": 2630, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-643/632 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 69.85×136.525×41.275 mm (assembled width T), for a shaft of about 69.85 mm (2.75 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 643 identifies the cone of 69.85 mm (2.75 in) bore by catalogue lookup, and 632 fixes the 136.525 mm OD. The 33.3 mm radial section over the 69.85 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 632: within the pure-numeric inch family tables the 643 cone is listed against several cup options, and it is the cup that fixes the 136.525 mm OD and the 41.275 mm assembled width — quote the full 643/632 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-643/632; reverse the fit logic when the cup rotates.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 69.85 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 2630 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 69.85 mm bore (136.525×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 643/632 reference at purchase.", "ABMA makes the 69.85×136.525 mm envelope interchangeable, not the ratings: NTN prints 215/262 kN for this execution and another make of the same number can differ in roller complement.", "Never drive the 136.525 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume inside the 41.275 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,800 r/min raises temperature and destroys the setting.", "The 215/262 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-643/632; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-643/632?", "a": "4T-643/632 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 69.85 mm bore (2.75 in), 136.525 mm outside diameter and 41.275 mm assembled width T (5.375 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 215 kN, C0 262 kN, grease limiting speed 2,800 r/min, oil speed 3,800 r/min, mass about 2630 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-643/632 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 643 cone or the 632 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 215/262 kN ratings change with the cup." }, { "q": "What is the difference between 4T-643/632 and a metric ISO 355 tapered bearing?", "a": "4T-643/632 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 69.85×136.525×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-643/632 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 643/632 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-643/632 list two speeds, 2,800 and 3,800 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-643/632 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "643", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-643-632", "643-632", "4T-643-632" ], "locale_variants": {} }, { "sku": "655-653", "brand": "NTN", "manufacturer_designation": "NTN 4T-655/653", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 146.05, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 228, "static_load_kN": 295, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 3280, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-655/653 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 69.85×146.05×41.275 mm (assembled width T), for a shaft of about 69.85 mm (2.75 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 655 identifies the cone of 69.85 mm (2.75 in) bore by catalogue lookup, and 653 fixes the 146.05 mm OD. Selection: C 228 kN against C0 295 kN gives a C0/C ratio of 1.29 for the 69.85 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-655/653: press the 653 cup square into the 146.05 mm seat first, then bring the 655 cone (on its 69.85 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-655/653 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 69.85 mm cone by induction heating (max 120 °C) and the 146.05 mm cup with a press sleeve; at 3280 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 69.85 mm bore (146.05×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 655/653 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Quote the full 655/653 pair at ordering: the 655 cone also ships against sibling cups, and a cup from another reference changes the 41.275 mm assembled width and the rating.", "An unloaded 4T-655/653 near 2,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 228/295 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-655/653; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-655/653?", "a": "4T-655/653 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 69.85 mm bore (2.75 in), 146.05 mm outside diameter and 41.275 mm assembled width T (5.75 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 228 kN, C0 295 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 3280 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-655/653 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 655 cone or the 653 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 228/295 kN ratings change with the cup." }, { "q": "What is the difference between 4T-655/653 and a metric ISO 355 tapered bearing?", "a": "4T-655/653 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 69.85×146.05×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-655/653 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 655/653 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-655/653 list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-655/653 at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "655-652", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-655-653", "655-653", "4T-655-653" ], "locale_variants": {} }, { "sku": "745A-742", "brand": "NTN", "manufacturer_designation": "NTN 4T-745A/742", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 150.089, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 289, "static_load_kN": 360, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3930, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 69.85 mm carrying combined radial and thrust load, NTN lists 4T-745A/742, a single-row 4T tapered roller set of 289 kN C and 360 kN C0 inside the 150.089 mm OD cup. Reading the designation: 4T-745A/742 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 40.1 mm radial section over the 69.85 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 742: within the pure-numeric inch family tables the 745A cone is listed against several cup options, and it is the cup that fixes the 150.089 mm OD and the 44.45 mm assembled width — quote the full 745A/742 pair, never the cone alone. Fillet radii must clear the chamfers of the 745A cone and 742 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 69.85 mm cone by induction heating (max 120 °C) and the 150.089 mm cup with a press sleeve; at 3930 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 69.85 mm bore (150.089×44.45 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 745A/742 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 44.45 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 44.45 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ABMA makes the 69.85×150.089 mm envelope interchangeable, not the ratings: NTN prints 289/360 kN for this execution and another make of the same number can differ in roller complement.", "The 289/360 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-745A/742; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-745A/742?", "a": "4T-745A/742 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 69.85 mm bore (2.75 in), 150.089 mm outside diameter and 44.45 mm assembled width T (5.909 × 1.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 289 kN, C0 360 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3930 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-745A/742 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 745A cone or the 742 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 289/360 kN ratings change with the cup." }, { "q": "What is the difference between 4T-745A/742 and a metric ISO 355 tapered bearing?", "a": "4T-745A/742 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 69.85×150.089×44.45 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-745A/742 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 745A/742 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-745A/742 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-745A/742 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "745A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-745a-742", "745a-742", "745A-742", "4T-745A-742" ], "locale_variants": {} }, { "sku": "835-832", "brand": "NTN", "manufacturer_designation": "NTN 4T-835/832", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 69.85, "D_mm": 168.275, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 375, "static_load_kN": 460, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 3000, "weight_g": 6140, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-835/832 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 835/832 without it. Catalogue mass of the 4T-835/832 cone-plus-cup set is 6140 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 375/460 kN ratings belong to the assembled 835+832 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-835/832 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 69.85 mm cone by induction heating (max 120 °C) and the 168.275 mm cup with a press sleeve; at 6140 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 69.85 mm bore (168.275×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 835/832 reference at purchase.", "Never drive the 168.275 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume inside the 53.975 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,000 r/min raises temperature and destroys the setting.", "Never drive the 168.275 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 375/460 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-835/832; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-835/832?", "a": "4T-835/832 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 69.85 mm bore (2.75 in), 168.275 mm outside diameter and 53.975 mm assembled width T (6.625 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 375 kN, C0 460 kN, grease limiting speed 2,200 r/min, oil speed 3,000 r/min, mass about 6140 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-835/832 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 835 cone or the 832 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 375/460 kN ratings change with the cup." }, { "q": "What is the difference between 4T-835/832 and a metric ISO 355 tapered bearing?", "a": "4T-835/832 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 69.85×168.275×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-835/832 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 835/832 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-835/832 list two speeds, 2,200 and 3,000 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-835/832 at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "835", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-835-832", "835-832", "4T-835-832" ], "locale_variants": {} }, { "sku": "34274-34478", "brand": "NTN", "manufacturer_designation": "NTN 4T-34274/34478", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 69.952, "D_mm": 121.442, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 101, "static_load_kN": 127, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 1110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 69.952 mm carrying combined radial and thrust load, NTN lists 4T-34274/34478, a single-row 4T tapered roller set of 101 kN C and 127 kN C0 inside the 121.442 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 34274 identifies the cone of 69.952 mm (2.754 in) bore by catalogue lookup, and 34478 fixes the 121.442 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 24.608 mm T of each 4T-34274/34478 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 101/127 kN ratings belong to the assembled 34274+34478 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-34274/34478 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 69.952 mm cone by induction heating (max 120 °C) and the 121.442 mm cup with a press sleeve; at 1110 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 69.952 mm bore (121.442×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 34274/34478 reference at purchase.", "Do not confuse T (24.608 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "ABMA makes the 69.952×121.442 mm envelope interchangeable, not the ratings: NTN prints 101/127 kN for this execution and another make of the same number can differ in roller complement.", "Open 4T-34274/34478 sets have no seals: a hub or gearbox needs external sealing or the 2,900 r/min grease figure is meaningless once water reaches the cone rib.", "The 101/127 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-34274/34478; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-34274/34478?", "a": "4T-34274/34478 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 69.952 mm bore (2.754 in), 121.442 mm outside diameter and 24.608 mm assembled width T (4.781 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 101 kN, C0 127 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 1110 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-34274/34478 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 34274 cone or the 34478 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 101/127 kN ratings change with the cup." }, { "q": "What is the difference between 4T-34274/34478 and a metric ISO 355 tapered bearing?", "a": "4T-34274/34478 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 69.952×121.442×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-34274/34478 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 34274/34478 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-34274/34478 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-34274/34478 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "34274", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-34274-34478", "34274-34478", "4T-34274-34478" ], "locale_variants": {} }, { "sku": "JLM813049-JLM813010", "brand": "NTN", "manufacturer_designation": "NTN 4T-JLM813049/JLM813010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 110, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 108, "static_load_kN": 150, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 888, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-JLM813049/JLM813010 denotes the JLM prefixed family of NTN inch tapered roller bearings — cone JLM813049 and cup JLM813010 delivered as a matched, separable pair of 70 mm bore and 110 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: JLM813049 identifies the cone of 70 mm (2.756 in) bore by catalogue lookup, and JLM813010 fixes the 110 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 26 mm T of each 4T-JLM813049/JLM813010 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for JLM813010: within the JLM prefixed family tables the JLM813049 cone is listed against several cup options, and it is the cup that fixes the 110 mm OD and the 26 mm assembled width — quote the full JLM813049/JLM813010 pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-JLM813049/JLM813010; reverse the fit logic when the cup rotates.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the 110 mm cup with a press sleeve; at 888 g a cocked ring brinells the raceway directly.", "The J-prefixed JLM813049 code belongs to a metric-envelope inch family: its 70 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Inch and metric bores collide on paper — 70 mm is 2.756 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Replacing one half of an adjusted pair without resetting end play negates the 26 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Shaft and housing fillets must clear the ring chamfers of JLM813049 and JLM813010; use undercut shoulders so the rings seat on the face, not on a radius.", "The 108/150 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JLM813049/JLM813010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JLM813049/JLM813010?", "a": "4T-JLM813049/JLM813010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 70 mm bore (2.756 in), 110 mm outside diameter and 26 mm assembled width T (4.331 × 1.024 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 108 kN, C0 150 kN, grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 888 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JLM813049/JLM813010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JLM813049 cone or the JLM813010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 108/150 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JLM813049/JLM813010 and a metric ISO 355 tapered bearing?", "a": "4T-JLM813049/JLM813010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 70×110×26 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JLM813049/JLM813010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JLM813049/JLM813010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JLM813049/JLM813010 list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JLM813049/JLM813010 at 4,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JLM813049", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jlm813049-jlm813010", "4t-jlm813049-jlm813010", "jlm813049-jlm813010", "JLM813049-JLM813010", "4T-JLM813049-JLM813010" ], "locale_variants": {} }, { "sku": "JM612949-JM612910", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM612949/JM612910", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 115, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 138, "static_load_kN": 171, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 1120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JM612949/JM612910 is the NTN 4T catalogue entry for a 70×115×29 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Reading the designation: 4T-JM612949/JM612910 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the JM metric-envelope family lettering ties the pair to its boundary plan. Selection: C 138 kN against C0 171 kN gives a C0/C ratio of 1.24 for the 70 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for JM612910: within the JM metric-envelope family tables the JM612949 cone is listed against several cup options, and it is the cup that fixes the 115 mm OD and the 29 mm assembled width — quote the full JM612949/JM612910 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-JM612949/JM612910, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the 115 mm cup with a press sleeve; at 1120 g a cocked ring brinells the raceway directly.", "The J-prefixed JM612949 code belongs to a metric-envelope inch family: its 70 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Do not confuse T (29 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Inch and metric bores collide on paper — 70 mm is 2.756 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Shaft and housing fillets must clear the ring chamfers of JM612949 and JM612910; use undercut shoulders so the rings seat on the face, not on a radius.", "The 138/171 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM612949/JM612910; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM612949/JM612910?", "a": "4T-JM612949/JM612910 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 70 mm bore (2.756 in), 115 mm outside diameter and 29 mm assembled width T (4.528 × 1.142 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 138 kN, C0 171 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 1120 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM612949/JM612910 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM612949 cone or the JM612910 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 138/171 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM612949/JM612910 and a metric ISO 355 tapered bearing?", "a": "4T-JM612949/JM612910 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 70×115×29 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM612949/JM612910 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM612949/JM612910 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM612949/JM612910 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM612949/JM612910 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM612949", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=187", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm612949-jm612910", "4t-jm612949-jm612910", "jm612949-jm612910", "JM612949-JM612910", "4T-JM612949-JM612910" ], "locale_variants": {} }, { "sku": "484-472", "brand": "NTN", "manufacturer_designation": "NTN 4T-484/472", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 120, "B_mm": 29.794, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 142, "static_load_kN": 177, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 70 mm carrying combined radial and thrust load, NTN lists 4T-484/472, a single-row 4T tapered roller set of 142 kN C and 177 kN C0 inside the 120 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 484/472 without it. Catalogue mass of the 4T-484/472 cone-plus-cup set is 1330 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-484/472: press the 472 cup square into the 120 mm seat first, then bring the 484 cone (on its 70 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-484/472 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the 120 mm cup with a press sleeve; at 1330 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 70 mm bore (120×29.794 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 484/472 reference at purchase.", "An unloaded 4T-484/472 near 3,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Grease packs must leave free volume inside the 29.794 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,000 r/min raises temperature and destroys the setting.", "ABMA makes the 70×120 mm envelope interchangeable, not the ratings: NTN prints 142/177 kN for this execution and another make of the same number can differ in roller complement.", "The 142/177 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-484/472; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-484/472?", "a": "4T-484/472 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 70 mm bore (2.756 in), 120 mm outside diameter and 29.794 mm assembled width T (4.724 × 1.173 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 142 kN, C0 177 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1330 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-484/472 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 484 cone or the 472 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 142/177 kN ratings change with the cup." }, { "q": "What is the difference between 4T-484/472 and a metric ISO 355 tapered bearing?", "a": "4T-484/472 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 70×120×29.794 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-484/472 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 484/472 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-484/472 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-484/472 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "484", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-484-472", "484-472", "4T-484-472" ], "locale_variants": {} }, { "sku": "JH913848-JH913811", "brand": "NTN", "manufacturer_designation": "NTN 4T-JH913848/JH913811", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 70, "D_mm": 150, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 220, "static_load_kN": 234, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3090, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.756 in (70 mm) shaft position as 4T-JH913848/JH913811: cone JH913848, cup JH913811, profiled rollers and a pressed-steel cage, rated 220 kN basic dynamic and 234 kN static. Reading the designation: 4T-JH913848/JH913811 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the JH heavy metric-envelope family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 70×150×41.275 mm converts to 2.756 × 5.906 × 1.625 in; the ABMA envelope swaps with like-numbered inch parts but the 220/234 kN ratings are NTN-specific. Housing fitment sequence for 4T-JH913848/JH913811: press the JH913811 cup square into the 150 mm seat first, then bring the JH913848 cone (on its 70 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-JH913848/JH913811 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 70 mm cone by induction heating (max 120 °C) and the 150 mm cup with a press sleeve; at 3090 g a cocked ring brinells the raceway directly.", "The J-prefixed JH913848 code belongs to a metric-envelope inch family: its 70 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Do not confuse T (41.275 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-JH913848/JH913811 sets have no seals: a hub or gearbox needs external sealing or the 2,400 r/min grease figure is meaningless once water reaches the cone rib.", "Inch and metric bores collide on paper — 70 mm is 2.756 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 220/234 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JH913848/JH913811; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JH913848/JH913811?", "a": "4T-JH913848/JH913811 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 70 mm bore (2.756 in), 150 mm outside diameter and 41.275 mm assembled width T (5.906 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 220 kN, C0 234 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3090 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JH913848/JH913811 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JH913848 cone or the JH913811 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 220/234 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JH913848/JH913811 and a metric ISO 355 tapered bearing?", "a": "4T-JH913848/JH913811 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 70×150×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JH913848/JH913811 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JH913848/JH913811 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JH913848/JH913811 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JH913848/JH913811 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JH913848", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jh913848-jh913811", "4t-jh913848-jh913811", "jh913848-jh913811", "JH913848-JH913811", "4T-JH913848-JH913811" ], "locale_variants": {} }, { "sku": "33281-33462-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-33281/33462", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 71.438, "D_mm": 117.475, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 129, "static_load_kN": 175, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 71.438 mm carrying combined radial and thrust load, NTN lists 4T-33281/33462, a single-row 4T tapered roller set of 129 kN C and 175 kN C0 inside the 117.475 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 33281 identifies the cone of 71.438 mm (2.813 in) bore by catalogue lookup, and 33462 fixes the 117.475 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-33281/33462 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 33462: within the pure-numeric inch family tables the 33281 cone is listed against several cup options, and it is the cup that fixes the 117.475 mm OD and the 30.162 mm assembled width — quote the full 33281/33462 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 71.438 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 71.438 mm cone by induction heating (max 120 °C) and the 117.475 mm cup with a press sleeve; at 1240 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 71.438 mm bore (117.475×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 33281/33462 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 33281 and 33462; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 71.438 mm is 2.813 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 129/175 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-33281/33462; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-33281/33462?", "a": "4T-33281/33462 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 71.438 mm bore (2.813 in), 117.475 mm outside diameter and 30.162 mm assembled width T (4.625 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 129 kN, C0 175 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1240 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-33281/33462 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 33281 cone or the 33462 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 129/175 kN ratings change with the cup." }, { "q": "What is the difference between 4T-33281/33462 and a metric ISO 355 tapered bearing?", "a": "4T-33281/33462 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 71.438×117.475×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-33281/33462 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 33281/33462 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-33281/33462 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-33281/33462 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "33281-33462", "equiv_brand": "SKF", "level": "partial", "note": "Same 71.438×117.475×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-33281-33462", "33281-33462", "4T-33281-33462", "33281-33462-NTN" ], "locale_variants": {} }, { "sku": "47490-47420", "brand": "NTN", "manufacturer_designation": "NTN 4T-47490/47420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 71.438, "D_mm": 120, "B_mm": 32.545, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 163, "static_load_kN": 214, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-47490/47420 at 71.438 mm bore (2.813 in), 120 mm cup OD and 32.545 mm assembled T, with a grease limiting speed of 3,000 r/min and an oil ceiling of 4,000 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 47490/47420 without it. Imperial cross-check for the drawing: 71.438×120×32.545 mm converts to 2.813 × 4.724 × 1.281 in; the ABMA envelope swaps with like-numbered inch parts but the 163/214 kN ratings are NTN-specific. Housing fitment sequence for 4T-47490/47420: press the 47420 cup square into the 120 mm seat first, then bring the 47490 cone (on its 71.438 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-47490/47420 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 71.438 mm cone by induction heating (max 120 °C) and the 120 mm cup with a press sleeve; at 1420 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 71.438 mm bore (120×32.545 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 47490/47420 reference at purchase.", "Quote the full 47490/47420 pair at ordering: the 47490 cone also ships against sibling cups, and a cup from another reference changes the 32.545 mm assembled width and the rating.", "Grease packs must leave free volume inside the 32.545 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,000 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of 47490 and 47420; use undercut shoulders so the rings seat on the face, not on a radius.", "The 163/214 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-47490/47420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-47490/47420?", "a": "4T-47490/47420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 71.438 mm bore (2.813 in), 120 mm outside diameter and 32.545 mm assembled width T (4.724 × 1.281 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 163 kN, C0 214 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1420 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-47490/47420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 47490 cone or the 47420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 163/214 kN ratings change with the cup." }, { "q": "What is the difference between 4T-47490/47420 and a metric ISO 355 tapered bearing?", "a": "4T-47490/47420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 71.438×120×32.545 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-47490/47420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 47490/47420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-47490/47420 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-47490/47420 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "47490", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-47490-47420", "47490-47420", "4T-47490-47420" ], "locale_variants": {} }, { "sku": "567A-563", "brand": "NTN", "manufacturer_designation": "NTN 4T-567A/563", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 71.438, "D_mm": 127, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 181, "static_load_kN": 229, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 1870, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-567A/563 at 71.438 mm bore (2.813 in), 127 mm cup OD and 36.512 mm assembled T, with a grease limiting speed of 2,900 r/min and an oil ceiling of 3,800 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 567A/563 without it. Selection: C 181 kN against C0 229 kN gives a C0/C ratio of 1.27 for the 71.438 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 181/229 kN ratings belong to the assembled 567A+563 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-567A/563; reverse the fit logic when the cup rotates.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 71.438 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 1870 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 71.438 mm bore (127×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 567A/563 reference at purchase.", "ABMA makes the 71.438×127 mm envelope interchangeable, not the ratings: NTN prints 181/229 kN for this execution and another make of the same number can differ in roller complement.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-567A/563 sets have no seals: a hub or gearbox needs external sealing or the 2,900 r/min grease figure is meaningless once water reaches the cone rib.", "The 181/229 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-567A/563; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-567A/563?", "a": "4T-567A/563 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 71.438 mm bore (2.813 in), 127 mm outside diameter and 36.512 mm assembled width T (5 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 229 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 1870 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-567A/563 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 567A cone or the 563 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 181/229 kN ratings change with the cup." }, { "q": "What is the difference between 4T-567A/563 and a metric ISO 355 tapered bearing?", "a": "4T-567A/563 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 71.438×127×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-567A/563 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 567A/563 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-567A/563 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-567A/563 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "567A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-567a-563", "567a-563", "567A-563", "4T-567A-563" ], "locale_variants": {} }, { "sku": "644-632", "brand": "NTN", "manufacturer_designation": "NTN 4T-644/632", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 71.438, "D_mm": 136.525, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 215, "static_load_kN": 262, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3800, "weight_g": 2580, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-644/632 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 644 and cup 632 delivered as a matched, separable pair of 71.438 mm bore and 136.525 mm outside diameter. Cone and cup of 4T-644/632 are separately stocked parts: a worn 632 cup can be replaced against the existing 644 cone, provided the new cup carries the identical reference — pairing across references changes the 41.275 mm assembled width and the rating. Catalogue mass of the 4T-644/632 cone-plus-cup set is 2580 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 215/262 kN ratings belong to the assembled 644+632 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-644/632 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 71.438 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 2580 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 71.438 mm bore (136.525×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 644/632 reference at purchase.", "Do not confuse T (41.275 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 71.438 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (41.275 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 215/262 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-644/632; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-644/632?", "a": "4T-644/632 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 71.438 mm bore (2.813 in), 136.525 mm outside diameter and 41.275 mm assembled width T (5.375 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 215 kN, C0 262 kN, grease limiting speed 2,800 r/min, oil speed 3,800 r/min, mass about 2580 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-644/632 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 644 cone or the 632 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 215/262 kN ratings change with the cup." }, { "q": "What is the difference between 4T-644/632 and a metric ISO 355 tapered bearing?", "a": "4T-644/632 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 71.438×136.525×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-644/632 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 644/632 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-644/632 list two speeds, 2,800 and 3,800 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-644/632 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "644", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-644-632", "644-632", "4T-644-632" ], "locale_variants": {} }, { "sku": "H414249-H414210", "brand": "NTN", "manufacturer_designation": "NTN 4T-H414249/H414210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 71.438, "D_mm": 136.525, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 251, "static_load_kN": 293, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3700, "weight_g": 2580, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 71.438 mm carrying combined radial and thrust load, NTN lists 4T-H414249/H414210, a single-row 4T tapered roller set of 251 kN C and 293 kN C0 inside the 136.525 mm OD cup. Reading the designation: 4T-H414249/H414210 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the heavy H family lettering ties the pair to its boundary plan. The 3.5 kN of dynamic capacity per millimetre of bore summarises the 251 kN rating over the 71.438 mm bore — sanity-check any interchange candidate against this ratio and the 41.275 mm T. The printed 251/293 kN ratings belong to the assembled H414249+H414210 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-H414249/H414210 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 71.438 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 2580 g a cocked ring brinells the raceway directly.", "The heavy H family at 71.438 mm bore (136.525×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full H414249/H414210 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 71.438 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of H414249 and H414210; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 71.438 mm is 2.813 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 251/293 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-H414249/H414210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-H414249/H414210?", "a": "4T-H414249/H414210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 71.438 mm bore (2.813 in), 136.525 mm outside diameter and 41.275 mm assembled width T (5.375 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 251 kN, C0 293 kN, grease limiting speed 2,700 r/min, oil speed 3,700 r/min, mass about 2580 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-H414249/H414210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the H414249 cone or the H414210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 251/293 kN ratings change with the cup." }, { "q": "What is the difference between 4T-H414249/H414210 and a metric ISO 355 tapered bearing?", "a": "4T-H414249/H414210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 71.438×136.525×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-H414249/H414210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare H414249/H414210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-H414249/H414210 list two speeds, 2,700 and 3,700 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-H414249/H414210 at 3,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "H414249", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-h414249-h414210", "h414249-h414210", "H414249-H414210", "4T-H414249-H414210" ], "locale_variants": {} }, { "sku": "H715345-H715311", "brand": "NTN", "manufacturer_designation": "NTN 4T-H715345/H715311", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 71.438, "D_mm": 136.525, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 248, "static_load_kN": 355, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 3110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-H715345/H715311 belongs to the NTN inch 4T tapered roller range (heavy H family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote H715345/H715311 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 46.038 mm T of each 4T-H715345/H715311 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-H715345/H715311: press the H715311 cup square into the 136.525 mm seat first, then bring the H715345 cone (on its 71.438 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-H715345/H715311; reverse the fit logic when the cup rotates.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 71.438 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 3110 g a cocked ring brinells the raceway directly.", "The heavy H family at 71.438 mm bore (136.525×46.038 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full H715345/H715311 reference at purchase.", "An unloaded 4T-H715345/H715311 near 2,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Quote the full H715345/H715311 pair at ordering: the H715345 cone also ships against sibling cups, and a cup from another reference changes the 46.038 mm assembled width and the rating.", "Never drive the 136.525 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 248/355 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-H715345/H715311; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-H715345/H715311?", "a": "4T-H715345/H715311 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 71.438 mm bore (2.813 in), 136.525 mm outside diameter and 46.038 mm assembled width T (5.375 × 1.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 248 kN, C0 355 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 3110 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-H715345/H715311 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the H715345 cone or the H715311 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 248/355 kN ratings change with the cup." }, { "q": "What is the difference between 4T-H715345/H715311 and a metric ISO 355 tapered bearing?", "a": "4T-H715345/H715311 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 71.438×136.525×46.038 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-H715345/H715311 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare H715345/H715311 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-H715345/H715311 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-H715345/H715311 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "H715345-311", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-h715345-h715311", "h715345-h715311", "H715345-H715311", "4T-H715345-H715311" ], "locale_variants": {} }, { "sku": "29685-29620-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-29685/29620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 73.025, "D_mm": 112.712, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 106, "static_load_kN": 151, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 874, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-29685/29620 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 29685 sits in the pure-numeric inch family. Contact-angle geometry of the pure-numeric inch family gives 4T-29685/29620 its radial/axial load split — at 106/151 kN the static rating is about 1.42× C, typical of inch tapered sets proportioned for combined duty. The printed 106/151 kN ratings belong to the assembled 29685+29620 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-29685/29620; reverse the fit logic when the cup rotates.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 73.025 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 874 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 73.025 mm bore (112.712×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 29685/29620 reference at purchase.", "ABMA makes the 73.025×112.712 mm envelope interchangeable, not the ratings: NTN prints 106/151 kN for this execution and another make of the same number can differ in roller complement.", "Shaft and housing fillets must clear the ring chamfers of 29685 and 29620; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-29685/29620 near 3,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 106/151 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-29685/29620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-29685/29620?", "a": "4T-29685/29620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 73.025 mm bore (2.875 in), 112.712 mm outside diameter and 25.4 mm assembled width T (4.437 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 106 kN, C0 151 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 874 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-29685/29620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 29685 cone or the 29620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 106/151 kN ratings change with the cup." }, { "q": "What is the difference between 4T-29685/29620 and a metric ISO 355 tapered bearing?", "a": "4T-29685/29620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 73.025×112.712×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-29685/29620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 29685/29620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-29685/29620 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-29685/29620 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "29685-29620", "equiv_brand": "SKF", "level": "partial", "note": "Same 73.025×112.712×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-29685-29620", "29685-29620", "4T-29685-29620", "29685-29620-NTN" ], "locale_variants": {} }, { "sku": "33287-33462-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-33287/33462", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 73.025, "D_mm": 117.475, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 129, "static_load_kN": 175, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 1190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-33287/33462 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 73.025×117.475×30.162 mm (assembled width T), for a shaft of about 73.025 mm (2.875 in). Cone and cup of 4T-33287/33462 are separately stocked parts: a worn 33462 cup can be replaced against the existing 33287 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Imperial cross-check for the drawing: 73.025×117.475×30.162 mm converts to 2.875 × 4.625 × 1.187 in; the ABMA envelope swaps with like-numbered inch parts but the 129/175 kN ratings are NTN-specific. Housing fitment sequence for 4T-33287/33462: press the 33462 cup square into the 117.475 mm seat first, then bring the 33287 cone (on its 73.025 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 73.025 mm cone with an induction heater (max 120 °C) and press the 117.475 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 73.025 mm cone by induction heating (max 120 °C) and the 117.475 mm cup with a press sleeve; at 1190 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 73.025 mm bore (117.475×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 33287/33462 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 33287 and 33462; use undercut shoulders so the rings seat on the face, not on a radius.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 129/175 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-33287/33462; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-33287/33462?", "a": "4T-33287/33462 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 73.025 mm bore (2.875 in), 117.475 mm outside diameter and 30.162 mm assembled width T (4.625 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 129 kN, C0 175 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 1190 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-33287/33462 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 33287 cone or the 33462 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 129/175 kN ratings change with the cup." }, { "q": "What is the difference between 4T-33287/33462 and a metric ISO 355 tapered bearing?", "a": "4T-33287/33462 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 73.025×117.475×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-33287/33462 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 33287/33462 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-33287/33462 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-33287/33462 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "33287-33462", "equiv_brand": "SKF", "level": "partial", "note": "Same 73.025×117.475×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-33287-33462", "33287-33462", "4T-33287-33462", "33287-33462-NTN" ], "locale_variants": {} }, { "sku": "567-563-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-567/563", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 73.025, "D_mm": 127, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 181, "static_load_kN": 229, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 1820, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-567/563 at 73.025 mm bore (2.875 in), 127 mm cup OD and 36.512 mm assembled T, with a grease limiting speed of 2,900 r/min and an oil ceiling of 3,800 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 567 identifies the cone of 73.025 mm (2.875 in) bore by catalogue lookup, and 563 fixes the 127 mm OD. The 2.5 kN of dynamic capacity per millimetre of bore summarises the 181 kN rating over the 73.025 mm bore — sanity-check any interchange candidate against this ratio and the 36.512 mm T. Housing fitment sequence for 4T-567/563: press the 563 cup square into the 127 mm seat first, then bring the 567 cone (on its 73.025 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-567/563 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 73.025 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 1820 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 73.025 mm bore (127×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 567/563 reference at purchase.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Inch and metric bores collide on paper — 73.025 mm is 2.875 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Never drive the 127 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 181/229 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-567/563; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-567/563?", "a": "4T-567/563 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 73.025 mm bore (2.875 in), 127 mm outside diameter and 36.512 mm assembled width T (5 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 229 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 1820 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-567/563 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 567 cone or the 563 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 181/229 kN ratings change with the cup." }, { "q": "What is the difference between 4T-567/563 and a metric ISO 355 tapered bearing?", "a": "4T-567/563 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 73.025×127×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-567/563 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 567/563 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-567/563 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-567/563 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "567-563", "equiv_brand": "SKF", "level": "partial", "note": "Same 73.025×127×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-567-563", "567-563", "4T-567-563", "567-563-NTN" ], "locale_variants": {} }, { "sku": "576-572", "brand": "NTN", "manufacturer_designation": "NTN 4T-576/572", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 73.025, "D_mm": 139.992, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 197, "static_load_kN": 265, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3400, "weight_g": 2520, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-576/572 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 576 and cup 572 delivered as a matched, separable pair of 73.025 mm bore and 139.992 mm outside diameter. Reading the designation: 4T-576/572 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 2.7 kN of dynamic capacity per millimetre of bore summarises the 197 kN rating over the 73.025 mm bore — sanity-check any interchange candidate against this ratio and the 36.512 mm T. Housing fitment sequence for 4T-576/572: press the 572 cup square into the 139.992 mm seat first, then bring the 576 cone (on its 73.025 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-576/572 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 73.025 mm cone by induction heating (max 120 °C) and the 139.992 mm cup with a press sleeve; at 2520 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 73.025 mm bore (139.992×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 576/572 reference at purchase.", "ABMA makes the 73.025×139.992 mm envelope interchangeable, not the ratings: NTN prints 197/265 kN for this execution and another make of the same number can differ in roller complement.", "Inch and metric bores collide on paper — 73.025 mm is 2.875 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-576/572 sets have no seals: a hub or gearbox needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 197/265 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-576/572; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-576/572?", "a": "4T-576/572 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 73.025 mm bore (2.875 in), 139.992 mm outside diameter and 36.512 mm assembled width T (5.511 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 197 kN, C0 265 kN, grease limiting speed 2,600 r/min, oil speed 3,400 r/min, mass about 2520 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-576/572 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 576 cone or the 572 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 197/265 kN ratings change with the cup." }, { "q": "What is the difference between 4T-576/572 and a metric ISO 355 tapered bearing?", "a": "4T-576/572 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 73.025×139.992×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-576/572 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 576/572 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-576/572 list two speeds, 2,600 and 3,400 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-576/572 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "576", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-576-572", "576-572", "4T-576-572" ], "locale_variants": {} }, { "sku": "6460-6420", "brand": "NTN", "manufacturer_designation": "NTN 4T-6460/6420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 73.025, "D_mm": 149.225, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 320, "static_load_kN": 410, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3400, "weight_g": 4430, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 73.025 mm carrying combined radial and thrust load, NTN lists 4T-6460/6420, a single-row 4T tapered roller set of 320 kN C and 410 kN C0 inside the 149.225 mm OD cup. Cone and cup of 4T-6460/6420 are separately stocked parts: a worn 6420 cup can be replaced against the existing 6460 cone, provided the new cup carries the identical reference — pairing across references changes the 53.975 mm assembled width and the rating. Selection: C 320 kN against C0 410 kN gives a C0/C ratio of 1.28 for the 73.025 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 320/410 kN ratings belong to the assembled 6460+6420 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 73.025 mm cone with an induction heater (max 120 °C) and press the 149.225 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 73.025 mm cone by induction heating (max 120 °C) and the 149.225 mm cup with a press sleeve; at 4430 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 73.025 mm bore (149.225×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 6460/6420 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 6460 and 6420; use undercut shoulders so the rings seat on the face, not on a radius.", "ABMA makes the 73.025×149.225 mm envelope interchangeable, not the ratings: NTN prints 320/410 kN for this execution and another make of the same number can differ in roller complement.", "Inch and metric bores collide on paper — 73.025 mm is 2.875 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 320/410 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-6460/6420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-6460/6420?", "a": "4T-6460/6420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 73.025 mm bore (2.875 in), 149.225 mm outside diameter and 53.975 mm assembled width T (5.875 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 320 kN, C0 410 kN, grease limiting speed 2,500 r/min, oil speed 3,400 r/min, mass about 4430 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-6460/6420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 6460 cone or the 6420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 320/410 kN ratings change with the cup." }, { "q": "What is the difference between 4T-6460/6420 and a metric ISO 355 tapered bearing?", "a": "4T-6460/6420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 73.025×149.225×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-6460/6420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 6460/6420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-6460/6420 list two speeds, 2,500 and 3,400 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-6460/6420 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "6460", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-6460-6420", "6460-6420", "4T-6460-6420" ], "locale_variants": {} }, { "sku": "744-742", "brand": "NTN", "manufacturer_designation": "NTN 4T-744/742", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 73.025, "D_mm": 150.089, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 289, "static_load_kN": 360, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 73.025 mm carrying combined radial and thrust load, NTN lists 4T-744/742, a single-row 4T tapered roller set of 289 kN C and 360 kN C0 inside the 150.089 mm OD cup. Reading the designation: 4T-744/742 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Contact-angle geometry of the pure-numeric inch family gives 4T-744/742 its radial/axial load split — at 289/360 kN the static rating is about 1.25× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-744/742: press the 742 cup square into the 150.089 mm seat first, then bring the 744 cone (on its 73.025 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-744/742; reverse the fit logic when the cup rotates.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 73.025 mm cone by induction heating (max 120 °C) and the 150.089 mm cup with a press sleeve; at 3800 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 73.025 mm bore (150.089×44.45 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 744/742 reference at purchase.", "Inch and metric bores collide on paper — 73.025 mm is 2.875 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Inch and metric bores collide on paper — 73.025 mm is 2.875 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "ABMA makes the 73.025×150.089 mm envelope interchangeable, not the ratings: NTN prints 289/360 kN for this execution and another make of the same number can differ in roller complement.", "The 289/360 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-744/742; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-744/742?", "a": "4T-744/742 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 73.025 mm bore (2.875 in), 150.089 mm outside diameter and 44.45 mm assembled width T (5.909 × 1.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 289 kN, C0 360 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3800 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-744/742 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 744 cone or the 742 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 289/360 kN ratings change with the cup." }, { "q": "What is the difference between 4T-744/742 and a metric ISO 355 tapered bearing?", "a": "4T-744/742 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 73.025×150.089×44.45 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-744/742 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 744/742 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-744/742 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-744/742 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "744", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-744-742", "744-742", "4T-744-742" ], "locale_variants": {} }, { "sku": "29688-29620", "brand": "NTN", "manufacturer_designation": "NTN 4T-29688/29620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 73.817, "D_mm": 112.712, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 106, "static_load_kN": 151, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 862, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-29688/29620 at 73.817 mm bore (2.906 in), 112.712 mm cup OD and 25.4 mm assembled T, with a grease limiting speed of 3,100 r/min and an oil ceiling of 4,100 r/min. Cone and cup of 4T-29688/29620 are separately stocked parts: a worn 29620 cup can be replaced against the existing 29688 cone, provided the new cup carries the identical reference — pairing across references changes the 25.4 mm assembled width and the rating. Selection: C 106 kN against C0 151 kN gives a C0/C ratio of 1.42 for the 73.817 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-29688/29620: press the 29620 cup square into the 112.712 mm seat first, then bring the 29688 cone (on its 73.817 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-29688/29620 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 73.817 mm cone by induction heating (max 120 °C) and the 112.712 mm cup with a press sleeve; at 862 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 73.817 mm bore (112.712×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 29688/29620 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 25.4 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 73.817 mm is 2.906 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 73.817 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 106/151 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-29688/29620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-29688/29620?", "a": "4T-29688/29620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 73.817 mm bore (2.906 in), 112.712 mm outside diameter and 25.4 mm assembled width T (4.437 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 106 kN, C0 151 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 862 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-29688/29620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 29688 cone or the 29620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 106/151 kN ratings change with the cup." }, { "q": "What is the difference between 4T-29688/29620 and a metric ISO 355 tapered bearing?", "a": "4T-29688/29620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 73.817×112.712×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-29688/29620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 29688/29620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-29688/29620 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-29688/29620 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "29688", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-29688-29620", "29688-29620", "4T-29688-29620" ], "locale_variants": {} }, { "sku": "568-563", "brand": "NTN", "manufacturer_designation": "NTN 4T-568/563", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 73.817, "D_mm": 127, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 181, "static_load_kN": 229, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 1800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-568/563 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 568 and cup 563 delivered as a matched, separable pair of 73.817 mm bore and 127 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 568/563 without it. The 26.6 mm radial section over the 73.817 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-568/563: press the 563 cup square into the 127 mm seat first, then bring the 568 cone (on its 73.817 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-568/563 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 73.817 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 1800 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 73.817 mm bore (127×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 568/563 reference at purchase.", "Grease packs must leave free volume inside the 36.512 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,800 r/min raises temperature and destroys the setting.", "Open 4T-568/563 sets have no seals: a hub or gearbox needs external sealing or the 2,900 r/min grease figure is meaningless once water reaches the cone rib.", "Inch and metric bores collide on paper — 73.817 mm is 2.906 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 181/229 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-568/563; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-568/563?", "a": "4T-568/563 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 73.817 mm bore (2.906 in), 127 mm outside diameter and 36.512 mm assembled width T (5 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 229 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 1800 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-568/563 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 568 cone or the 563 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 181/229 kN ratings change with the cup." }, { "q": "What is the difference between 4T-568/563 and a metric ISO 355 tapered bearing?", "a": "4T-568/563 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 73.817×127×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-568/563 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 568/563 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-568/563 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-568/563 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "568", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-568-563", "568-563", "4T-568-563" ], "locale_variants": {} }, { "sku": "577-572", "brand": "NTN", "manufacturer_designation": "NTN 4T-577/572", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 74.612, "D_mm": 139.992, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 197, "static_load_kN": 265, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3400, "weight_g": 2470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 2.937 in (74.612 mm) shaft position as 4T-577/572: cone 577, cup 572, profiled rollers and a pressed-steel cage, rated 197 kN basic dynamic and 265 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 577/572 without it. Imperial cross-check for the drawing: 74.612×139.992×36.512 mm converts to 2.937 × 5.511 × 1.437 in; the ABMA envelope swaps with like-numbered inch parts but the 197/265 kN ratings are NTN-specific. Cup-side note for 572: within the pure-numeric inch family tables the 577 cone is listed against several cup options, and it is the cup that fixes the 139.992 mm OD and the 36.512 mm assembled width — quote the full 577/572 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-577/572 run near 2,600 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 74.612 mm cone by induction heating (max 120 °C) and the 139.992 mm cup with a press sleeve; at 2470 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 74.612 mm bore (139.992×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 577/572 reference at purchase.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Shaft and housing fillets must clear the ring chamfers of 577 and 572; use undercut shoulders so the rings seat on the face, not on a radius.", "Fit selection follows the rotating ring: a rotating cone on a 74.612 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 197/265 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-577/572; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-577/572?", "a": "4T-577/572 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 74.612 mm bore (2.937 in), 139.992 mm outside diameter and 36.512 mm assembled width T (5.511 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 197 kN, C0 265 kN, grease limiting speed 2,600 r/min, oil speed 3,400 r/min, mass about 2470 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-577/572 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 577 cone or the 572 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 197/265 kN ratings change with the cup." }, { "q": "What is the difference between 4T-577/572 and a metric ISO 355 tapered bearing?", "a": "4T-577/572 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 74.612×139.992×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-577/572 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 577/572 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-577/572 list two speeds, 2,600 and 3,400 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-577/572 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "577", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-577-572", "577-572", "4T-577-572" ], "locale_variants": {} }, { "sku": "JLM714149-JLM714110", "brand": "NTN", "manufacturer_designation": "NTN 4T-JLM714149/JLM714110", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 115, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 105, "static_load_kN": 143, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 880, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-JLM714149/JLM714110 at 75 mm bore (2.953 in), 115 mm cup OD and 25 mm assembled T, with a grease limiting speed of 3,000 r/min and an oil ceiling of 4,000 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: JLM714149 identifies the cone of 75 mm (2.953 in) bore by catalogue lookup, and JLM714110 fixes the 115 mm OD. The 1.4 kN of dynamic capacity per millimetre of bore summarises the 105 kN rating over the 75 mm bore — sanity-check any interchange candidate against this ratio and the 25 mm T. Cup-side note for JLM714110: within the JLM prefixed family tables the JLM714149 cone is listed against several cup options, and it is the cup that fixes the 115 mm OD and the 25 mm assembled width — quote the full JLM714149/JLM714110 pair, never the cone alone. Fillet radii must clear the chamfers of the JLM714149 cone and JLM714110 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the 115 mm cup with a press sleeve; at 880 g a cocked ring brinells the raceway directly.", "The J-prefixed JLM714149 code belongs to a metric-envelope inch family: its 75 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Never drive the 115 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Shaft and housing fillets must clear the ring chamfers of JLM714149 and JLM714110; use undercut shoulders so the rings seat on the face, not on a radius.", "Open 4T-JLM714149/JLM714110 sets have no seals: a hub or gearbox needs external sealing or the 3,000 r/min grease figure is meaningless once water reaches the cone rib.", "The 105/143 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JLM714149/JLM714110; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JLM714149/JLM714110?", "a": "4T-JLM714149/JLM714110 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 75 mm bore (2.953 in), 115 mm outside diameter and 25 mm assembled width T (4.528 × 0.984 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 105 kN, C0 143 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 880 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JLM714149/JLM714110 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JLM714149 cone or the JLM714110 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 105/143 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JLM714149/JLM714110 and a metric ISO 355 tapered bearing?", "a": "4T-JLM714149/JLM714110 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 75×115×25 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JLM714149/JLM714110 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JLM714149/JLM714110 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JLM714149/JLM714110 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JLM714149/JLM714110 at 4,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JLM714149", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jlm714149-jlm714110", "4t-jlm714149-jlm714110", "jlm714149-jlm714110", "JLM714149-JLM714110", "4T-JLM714149-JLM714110" ], "locale_variants": {} }, { "sku": "JM714249-JM714210", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM714249/JM714210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 120, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 145, "static_load_kN": 197, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3900, "weight_g": 1290, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JM714249/JM714210 belongs to the NTN inch 4T tapered roller range (JM metric-envelope family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote JM714249/JM714210 without it. Catalogue mass of the 4T-JM714249/JM714210 cone-plus-cup set is 1290 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 145/197 kN ratings belong to the assembled JM714249+JM714210 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 75 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the 120 mm cup with a press sleeve; at 1290 g a cocked ring brinells the raceway directly.", "The J-prefixed JM714249 code belongs to a metric-envelope inch family: its 75 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Quote the full JM714249/JM714210 pair at ordering: the JM714249 cone also ships against sibling cups, and a cup from another reference changes the 31 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of JM714249 and JM714210; use undercut shoulders so the rings seat on the face, not on a radius.", "Replacing one half of an adjusted pair without resetting end play negates the 31 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 145/197 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM714249/JM714210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM714249/JM714210?", "a": "4T-JM714249/JM714210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 75 mm bore (2.953 in), 120 mm outside diameter and 31 mm assembled width T (4.724 × 1.22 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 145 kN, C0 197 kN, grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 1290 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM714249/JM714210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM714249 cone or the JM714210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 145/197 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM714249/JM714210 and a metric ISO 355 tapered bearing?", "a": "4T-JM714249/JM714210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 75×120×31 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM714249/JM714210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM714249/JM714210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM714249/JM714210 list two speeds, 2,900 and 3,900 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM714249/JM714210 at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM714249", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm714249-jm714210", "4t-jm714249-jm714210", "jm714249-jm714210", "JM714249-JM714210", "4T-JM714249-JM714210" ], "locale_variants": {} }, { "sku": "JH415647-JH415610", "brand": "NTN", "manufacturer_designation": "NTN 4T-JH415647/JH415610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 75, "D_mm": 145, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 320, "static_load_kN": 410, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3400, "weight_g": 3820, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 75 mm carrying combined radial and thrust load, NTN lists 4T-JH415647/JH415610, a single-row 4T tapered roller set of 320 kN C and 410 kN C0 inside the 145 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — JH415647 sits in the JH heavy metric-envelope family. Contact-angle geometry of the JH heavy metric-envelope family gives 4T-JH415647/JH415610 its radial/axial load split — at 320/410 kN the static rating is about 1.28× C, typical of inch tapered sets proportioned for combined duty. The printed 320/410 kN ratings belong to the assembled JH415647+JH415610 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-JH415647/JH415610 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 75 mm cone by induction heating (max 120 °C) and the 145 mm cup with a press sleeve; at 3820 g a cocked ring brinells the raceway directly.", "The J-prefixed JH415647 code belongs to a metric-envelope inch family: its 75 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Quote the full JH415647/JH415610 pair at ordering: the JH415647 cone also ships against sibling cups, and a cup from another reference changes the 51 mm assembled width and the rating.", "Never drive the 145 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 75×145 mm envelope interchangeable, not the ratings: NTN prints 320/410 kN for this execution and another make of the same number can differ in roller complement.", "The 320/410 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JH415647/JH415610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JH415647/JH415610?", "a": "4T-JH415647/JH415610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 75 mm bore (2.953 in), 145 mm outside diameter and 51 mm assembled width T (5.709 × 2.008 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 320 kN, C0 410 kN, grease limiting speed 2,500 r/min, oil speed 3,400 r/min, mass about 3820 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JH415647/JH415610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JH415647 cone or the JH415610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 320/410 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JH415647/JH415610 and a metric ISO 355 tapered bearing?", "a": "4T-JH415647/JH415610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 75×145×51 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JH415647/JH415610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JH415647/JH415610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JH415647/JH415610 list two speeds, 2,500 and 3,400 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JH415647/JH415610 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JH415647", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jh415647-jh415610", "4t-jh415647-jh415610", "jh415647-jh415610", "JH415647-JH415610", "4T-JH415647-JH415610" ], "locale_variants": {} }, { "sku": "L814749-L814710", "brand": "NTN", "manufacturer_designation": "NTN 4T-L814749/L814710", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 109.538, "B_mm": 19.05, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 70, "static_load_kN": 115, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 579, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 76.2 mm carrying combined radial and thrust load, NTN lists 4T-L814749/L814710, a single-row 4T tapered roller set of 70 kN C and 115 kN C0 inside the 109.538 mm OD cup. Reading the designation: 4T-L814749/L814710 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the light L family lettering ties the pair to its boundary plan. The 16.7 mm radial section over the 76.2 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-L814749/L814710: press the L814710 cup square into the 109.538 mm seat first, then bring the L814749 cone (on its 76.2 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-L814749/L814710 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 109.538 mm cup with a press sleeve; at 579 g a cocked ring brinells the raceway directly.", "The light L family at 76.2 mm bore (109.538×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L814749/L814710 reference at purchase.", "Do not confuse T (19.05 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Grease packs must leave free volume inside the 19.05 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,100 r/min raises temperature and destroys the setting.", "Never drive the 109.538 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 70/115 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L814749/L814710; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L814749/L814710?", "a": "4T-L814749/L814710 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 109.538 mm outside diameter and 19.05 mm assembled width T (4.313 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 70 kN, C0 115 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 579 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L814749/L814710 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L814749 cone or the L814710 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 70/115 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L814749/L814710 and a metric ISO 355 tapered bearing?", "a": "4T-L814749/L814710 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×109.538×19.05 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L814749/L814710 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L814749/L814710 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L814749/L814710 list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L814749/L814710 at 4,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L814749-710", "equiv_brand": "SKF", "level": "partial", "note": "Same 76.2×109.538×19.05 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l814749-l814710", "l814749-l814710", "L814749-L814710", "4T-L814749-L814710" ], "locale_variants": {} }, { "sku": "34300-34478", "brand": "NTN", "manufacturer_designation": "NTN 4T-34300/34478", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 121.442, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 101, "static_load_kN": 127, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 978, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 76.2 mm carrying combined radial and thrust load, NTN lists 4T-34300/34478, a single-row 4T tapered roller set of 101 kN C and 127 kN C0 inside the 121.442 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 34300/34478 without it. Selection: C 101 kN against C0 127 kN gives a C0/C ratio of 1.26 for the 76.2 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-34300/34478: press the 34478 cup square into the 121.442 mm seat first, then bring the 34300 cone (on its 76.2 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Fillet radii must clear the chamfers of the 34300 cone and 34478 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 121.442 mm cup with a press sleeve; at 978 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (121.442×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 34300/34478 reference at purchase.", "Never drive the 121.442 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (24.608 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 76.2 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 101/127 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-34300/34478; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-34300/34478?", "a": "4T-34300/34478 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 121.442 mm outside diameter and 24.608 mm assembled width T (4.781 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 101 kN, C0 127 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 978 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-34300/34478 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 34300 cone or the 34478 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 101/127 kN ratings change with the cup." }, { "q": "What is the difference between 4T-34300/34478 and a metric ISO 355 tapered bearing?", "a": "4T-34300/34478 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×121.442×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-34300/34478 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 34300/34478 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-34300/34478 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-34300/34478 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "34300", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-34300-34478", "34300-34478", "4T-34300-34478" ], "locale_variants": {} }, { "sku": "34301-34478", "brand": "NTN", "manufacturer_designation": "NTN 4T-34301/34478", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 121.442, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 101, "static_load_kN": 127, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 976, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-34301/34478 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-34301/34478 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 2,900 r/min limiting speed targets the cone-rib contact; sustaining 3,800 r/min needs an oil supply directed at the large roller ends. Cup-side note for 34478: within the pure-numeric inch family tables the 34301 cone is listed against several cup options, and it is the cup that fixes the 121.442 mm OD and the 24.608 mm assembled width — quote the full 34301/34478 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-34301/34478 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 121.442 mm cup with a press sleeve; at 976 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (121.442×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 34301/34478 reference at purchase.", "Never drive the 121.442 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 76.2×121.442 mm envelope interchangeable, not the ratings: NTN prints 101/127 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-34301/34478 near 2,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 101/127 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-34301/34478; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-34301/34478?", "a": "4T-34301/34478 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 121.442 mm outside diameter and 24.608 mm assembled width T (4.781 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 101 kN, C0 127 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 976 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-34301/34478 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 34301 cone or the 34478 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 101/127 kN ratings change with the cup." }, { "q": "What is the difference between 4T-34301/34478 and a metric ISO 355 tapered bearing?", "a": "4T-34301/34478 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×121.442×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-34301/34478 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 34301/34478 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-34301/34478 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-34301/34478 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "34301", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-34301-34478", "34301-34478", "4T-34301-34478" ], "locale_variants": {} }, { "sku": "42687-42620-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-42687/42620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 127, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 150, "static_load_kN": 194, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3700, "weight_g": 1460, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-42687/42620 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 42687/42620 without it. Speed planning uses both catalogue columns: grease 2,800 r/min is the mechanical ceiling for 4T-42687/42620, oil 3,700 r/min with circulating oil — a 900 r/min margin at this size. Cup-side note for 42620: within the pure-numeric inch family tables the 42687 cone is listed against several cup options, and it is the cup that fixes the 127 mm OD and the 30.162 mm assembled width — quote the full 42687/42620 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-42687/42620 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 1460 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (127×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 42687/42620 reference at purchase.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,700 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 76.2 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,700 r/min raises temperature and destroys the setting.", "The 150/194 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-42687/42620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-42687/42620?", "a": "4T-42687/42620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 127 mm outside diameter and 30.162 mm assembled width T (5 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 150 kN, C0 194 kN, grease limiting speed 2,800 r/min, oil speed 3,700 r/min, mass about 1460 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-42687/42620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 42687 cone or the 42620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 150/194 kN ratings change with the cup." }, { "q": "What is the difference between 4T-42687/42620 and a metric ISO 355 tapered bearing?", "a": "4T-42687/42620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×127×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-42687/42620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 42687/42620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-42687/42620 list two speeds, 2,800 and 3,700 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-42687/42620 at 3,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "42687-42620", "equiv_brand": "SKF", "level": "partial", "note": "Same 76.2×127×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-42687-42620", "42687-42620", "4T-42687-42620", "42687-42620-NTN" ], "locale_variants": {} }, { "sku": "47678-47620-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-47678/47620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 133.35, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 170, "static_load_kN": 235, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1920, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3 in (76.2 mm) shaft position as 4T-47678/47620: cone 47678, cup 47620, profiled rollers and a pressed-steel cage, rated 170 kN basic dynamic and 235 kN static. Cone and cup of 4T-47678/47620 are separately stocked parts: a worn 47620 cup can be replaced against the existing 47678 cone, provided the new cup carries the identical reference — pairing across references changes the 33.338 mm assembled width and the rating. Grease relubrication at the 2,600 r/min limiting speed targets the cone-rib contact; sustaining 3,500 r/min needs an oil supply directed at the large roller ends. The printed 170/235 kN ratings belong to the assembled 47678+47620 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-47678/47620 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 133.35 mm cup with a press sleeve; at 1920 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (133.35×33.338 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 47678/47620 reference at purchase.", "Open 4T-47678/47620 sets have no seals: a hub or gearbox needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "Fit selection follows the rotating ring: a rotating cone on a 76.2 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 33.338 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,500 r/min raises temperature and destroys the setting.", "The 170/235 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-47678/47620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-47678/47620?", "a": "4T-47678/47620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 133.35 mm outside diameter and 33.338 mm assembled width T (5.25 × 1.313 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 170 kN, C0 235 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1920 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-47678/47620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 47678 cone or the 47620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 170/235 kN ratings change with the cup." }, { "q": "What is the difference between 4T-47678/47620 and a metric ISO 355 tapered bearing?", "a": "4T-47678/47620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×133.35×33.338 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-47678/47620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 47678/47620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-47678/47620 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-47678/47620 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "47678-47620", "equiv_brand": "SKF", "level": "partial", "note": "Same 76.2×133.35×33.338 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-47678-47620", "47678-47620", "4T-47678-47620", "47678-47620-NTN" ], "locale_variants": {} }, { "sku": "HM516442-HM516410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM516442/HM516410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 133.35, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 196, "static_load_kN": 305, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 2430, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM516442/HM516410 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 76.2×133.35×39.688 mm (assembled width T), for a shaft of about 76.2 mm (3 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HM516442 sits in the heavy-medium HM family. Speed planning uses both catalogue columns: grease 2,600 r/min is the mechanical ceiling for 4T-HM516442/HM516410, oil 3,500 r/min with circulating oil — a 900 r/min margin at this size. Cup-side note for HM516410: within the heavy-medium HM family tables the HM516442 cone is listed against several cup options, and it is the cup that fixes the 133.35 mm OD and the 39.688 mm assembled width — quote the full HM516442/HM516410 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-HM516442/HM516410 run near 2,600 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 133.35 mm cup with a press sleeve; at 2430 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 76.2 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Open 4T-HM516442/HM516410 sets have no seals: a hub or gearbox needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "Quote the full HM516442/HM516410 pair at ordering: the HM516442 cone also ships against sibling cups, and a cup from another reference changes the 39.688 mm assembled width and the rating.", "ABMA makes the 76.2×133.35 mm envelope interchangeable, not the ratings: NTN prints 196/305 kN for this execution and another make of the same number can differ in roller complement.", "The 196/305 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM516442/HM516410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM516442/HM516410?", "a": "4T-HM516442/HM516410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 133.35 mm outside diameter and 39.688 mm assembled width T (5.25 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 196 kN, C0 305 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 2430 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM516442/HM516410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM516442 cone or the HM516410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 196/305 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM516442/HM516410 and a metric ISO 355 tapered bearing?", "a": "4T-HM516442/HM516410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×133.35×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM516442/HM516410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM516442/HM516410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM516442/HM516410 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM516442/HM516410 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM516442", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm516442-hm516410", "hm516442-hm516410", "HM516442-HM516410", "4T-HM516442-HM516410" ], "locale_variants": {} }, { "sku": "5760-5735", "brand": "NTN", "manufacturer_designation": "NTN 4T-5760/5735", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 135.733, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 235, "static_load_kN": 330, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3500, "weight_g": 2750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-5760/5735 at 76.2 mm bore (3 in), 135.733 mm cup OD and 44.45 mm assembled T, with a grease limiting speed of 2,700 r/min and an oil ceiling of 3,500 r/min. Reading the designation: 4T-5760/5735 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 29.8 mm radial section over the 76.2 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 235/330 kN ratings belong to the assembled 5760+5735 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 76.2 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 135.733 mm cup with a press sleeve; at 2750 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (135.733×44.45 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 5760/5735 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 76.2 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Open 4T-5760/5735 sets have no seals: a hub or gearbox needs external sealing or the 2,700 r/min grease figure is meaningless once water reaches the cone rib.", "Fit selection follows the rotating ring: a rotating cone on a 76.2 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 235/330 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-5760/5735; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-5760/5735?", "a": "4T-5760/5735 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 135.733 mm outside diameter and 44.45 mm assembled width T (5.344 × 1.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 235 kN, C0 330 kN, grease limiting speed 2,700 r/min, oil speed 3,500 r/min, mass about 2750 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-5760/5735 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 5760 cone or the 5735 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 235/330 kN ratings change with the cup." }, { "q": "What is the difference between 4T-5760/5735 and a metric ISO 355 tapered bearing?", "a": "4T-5760/5735 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×135.733×44.45 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-5760/5735 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 5760/5735 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-5760/5735 list two speeds, 2,700 and 3,500 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-5760/5735 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "5760", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-5760-5735", "5760-5735", "4T-5760-5735" ], "locale_variants": {} }, { "sku": "495A-493", "brand": "NTN", "manufacturer_designation": "NTN 4T-495A/493", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 136.525, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 143, "static_load_kN": 189, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1830, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-495A/493 is the NTN 4T catalogue entry for a 76.2×136.525×30.162 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 495A sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-495A/493 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-495A/493: press the 493 cup square into the 136.525 mm seat first, then bring the 495A cone (on its 76.2 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-495A/493; reverse the fit logic when the cup rotates.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 1830 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (136.525×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 495A/493 reference at purchase.", "An unloaded 4T-495A/493 near 2,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Shaft and housing fillets must clear the ring chamfers of 495A and 493; use undercut shoulders so the rings seat on the face, not on a radius.", "The 143/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-495A/493; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-495A/493?", "a": "4T-495A/493 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 136.525 mm outside diameter and 30.162 mm assembled width T (5.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 143 kN, C0 189 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1830 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-495A/493 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 495A cone or the 493 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 143/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-495A/493 and a metric ISO 355 tapered bearing?", "a": "4T-495A/493 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×136.525×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-495A/493 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 495A/493 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-495A/493 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-495A/493 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "495A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "495a-493", "4t-495a-493", "495A-493", "4T-495A-493" ], "locale_variants": {} }, { "sku": "575-572-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-575/572", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 139.992, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 197, "static_load_kN": 265, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3400, "weight_g": 2420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-575/572 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 76.2×139.992×36.512 mm (assembled width T), for a shaft of about 76.2 mm (3 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 575/572 without it. Catalogue mass of the 4T-575/572 cone-plus-cup set is 2420 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-575/572: press the 572 cup square into the 139.992 mm seat first, then bring the 575 cone (on its 76.2 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-575/572 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 139.992 mm cup with a press sleeve; at 2420 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (139.992×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 575/572 reference at purchase.", "Grease packs must leave free volume inside the 36.512 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,400 r/min raises temperature and destroys the setting.", "ABMA makes the 76.2×139.992 mm envelope interchangeable, not the ratings: NTN prints 197/265 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 575/572 pair at ordering: the 575 cone also ships against sibling cups, and a cup from another reference changes the 36.512 mm assembled width and the rating.", "The 197/265 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-575/572; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-575/572?", "a": "4T-575/572 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 139.992 mm outside diameter and 36.512 mm assembled width T (5.511 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 197 kN, C0 265 kN, grease limiting speed 2,600 r/min, oil speed 3,400 r/min, mass about 2420 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-575/572 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 575 cone or the 572 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 197/265 kN ratings change with the cup." }, { "q": "What is the difference between 4T-575/572 and a metric ISO 355 tapered bearing?", "a": "4T-575/572 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×139.992×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-575/572 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 575/572 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-575/572 list two speeds, 2,600 and 3,400 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-575/572 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "575-572", "equiv_brand": "SKF", "level": "partial", "note": "Same 76.2×139.992×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-575-572", "575-572", "4T-575-572", "575-572-NTN" ], "locale_variants": {} }, { "sku": "575S-572", "brand": "NTN", "manufacturer_designation": "NTN 4T-575S/572", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 139.992, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 197, "static_load_kN": 265, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3400, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-575S/572 at 76.2 mm bore (3 in), 139.992 mm cup OD and 36.512 mm assembled T, with a grease limiting speed of 2,600 r/min and an oil ceiling of 3,400 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 575S sits in the pure-numeric inch family. The 31.9 mm radial section over the 76.2 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 572: within the pure-numeric inch family tables the 575S cone is listed against several cup options, and it is the cup that fixes the 139.992 mm OD and the 36.512 mm assembled width — quote the full 575S/572 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 76.2 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 139.992 mm cup with a press sleeve; at 2400 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (139.992×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 575S/572 reference at purchase.", "ABMA makes the 76.2×139.992 mm envelope interchangeable, not the ratings: NTN prints 197/265 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-575S/572 near 2,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Quote the full 575S/572 pair at ordering: the 575S cone also ships against sibling cups, and a cup from another reference changes the 36.512 mm assembled width and the rating.", "The 197/265 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-575S/572; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-575S/572?", "a": "4T-575S/572 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 139.992 mm outside diameter and 36.512 mm assembled width T (5.511 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 197 kN, C0 265 kN, grease limiting speed 2,600 r/min, oil speed 3,400 r/min, mass about 2400 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-575S/572 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 575S cone or the 572 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 197/265 kN ratings change with the cup." }, { "q": "What is the difference between 4T-575S/572 and a metric ISO 355 tapered bearing?", "a": "4T-575S/572 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×139.992×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-575S/572 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 575S/572 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-575S/572 list two speeds, 2,600 and 3,400 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-575S/572 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "575S", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-575s-572", "575s-572", "575S-572", "4T-575S-572" ], "locale_variants": {} }, { "sku": "659-653", "brand": "NTN", "manufacturer_designation": "NTN 4T-659/653", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 146.05, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 228, "static_load_kN": 295, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 3040, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-659/653 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 76.2×146.05×41.275 mm (assembled width T), for a shaft of about 76.2 mm (3 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 659 identifies the cone of 76.2 mm (3 in) bore by catalogue lookup, and 653 fixes the 146.05 mm OD. Contact-angle geometry of the pure-numeric inch family gives 4T-659/653 its radial/axial load split — at 228/295 kN the static rating is about 1.29× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-659/653: press the 653 cup square into the 146.05 mm seat first, then bring the 659 cone (on its 76.2 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 76.2 mm cone with an induction heater (max 120 °C) and press the 146.05 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 146.05 mm cup with a press sleeve; at 3040 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (146.05×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 659/653 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 659 and 653; use undercut shoulders so the rings seat on the face, not on a radius.", "Fit selection follows the rotating ring: a rotating cone on a 76.2 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 76.2×146.05 mm envelope interchangeable, not the ratings: NTN prints 228/295 kN for this execution and another make of the same number can differ in roller complement.", "The 228/295 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-659/653; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-659/653?", "a": "4T-659/653 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 146.05 mm outside diameter and 41.275 mm assembled width T (5.75 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 228 kN, C0 295 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 3040 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-659/653 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 659 cone or the 653 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 228/295 kN ratings change with the cup." }, { "q": "What is the difference between 4T-659/653 and a metric ISO 355 tapered bearing?", "a": "4T-659/653 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×146.05×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-659/653 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 659/653 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-659/653 list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-659/653 at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "659", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-659-653", "659-653", "4T-659-653" ], "locale_variants": {} }, { "sku": "6461-6420", "brand": "NTN", "manufacturer_designation": "NTN 4T-6461/6420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 149.225, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 320, "static_load_kN": 410, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3400, "weight_g": 4260, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-6461/6420 is the NTN 4T catalogue entry for a 76.2×149.225×53.975 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 6461 identifies the cone of 76.2 mm (3 in) bore by catalogue lookup, and 6420 fixes the 149.225 mm OD. Selection: C 320 kN against C0 410 kN gives a C0/C ratio of 1.28 for the 76.2 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 320/410 kN ratings belong to the assembled 6461+6420 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 6461 cone and 6420 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 149.225 mm cup with a press sleeve; at 4260 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (149.225×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 6461/6420 reference at purchase.", "Do not confuse T (53.975 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 76.2 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Replacing one half of an adjusted pair without resetting end play negates the 53.975 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 320/410 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-6461/6420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-6461/6420?", "a": "4T-6461/6420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 149.225 mm outside diameter and 53.975 mm assembled width T (5.875 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 320 kN, C0 410 kN, grease limiting speed 2,500 r/min, oil speed 3,400 r/min, mass about 4260 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-6461/6420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 6461 cone or the 6420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 320/410 kN ratings change with the cup." }, { "q": "What is the difference between 4T-6461/6420 and a metric ISO 355 tapered bearing?", "a": "4T-6461/6420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×149.225×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-6461/6420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 6461/6420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-6461/6420 list two speeds, 2,500 and 3,400 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-6461/6420 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "6461", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-6461-6420", "6461-6420", "4T-6461-6420" ], "locale_variants": {} }, { "sku": "6461A-6420", "brand": "NTN", "manufacturer_designation": "NTN 4T-6461A/6420", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 149.225, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 320, "static_load_kN": 410, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3400, "weight_g": 4240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-6461A/6420 at 76.2 mm bore (3 in), 149.225 mm cup OD and 53.975 mm assembled T, with a grease limiting speed of 2,500 r/min and an oil ceiling of 3,400 r/min. Reading the designation: 4T-6461A/6420 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Catalogue mass of the 4T-6461A/6420 cone-plus-cup set is 4240 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-6461A/6420: press the 6420 cup square into the 149.225 mm seat first, then bring the 6461A cone (on its 76.2 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-6461A/6420 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 149.225 mm cup with a press sleeve; at 4240 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (149.225×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 6461A/6420 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 53.975 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Quote the full 6461A/6420 pair at ordering: the 6461A cone also ships against sibling cups, and a cup from another reference changes the 53.975 mm assembled width and the rating.", "Quote the full 6461A/6420 pair at ordering: the 6461A cone also ships against sibling cups, and a cup from another reference changes the 53.975 mm assembled width and the rating.", "The 320/410 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-6461A/6420; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-6461A/6420?", "a": "4T-6461A/6420 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 149.225 mm outside diameter and 53.975 mm assembled width T (5.875 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 320 kN, C0 410 kN, grease limiting speed 2,500 r/min, oil speed 3,400 r/min, mass about 4240 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-6461A/6420 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 6461A cone or the 6420 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 320/410 kN ratings change with the cup." }, { "q": "What is the difference between 4T-6461A/6420 and a metric ISO 355 tapered bearing?", "a": "4T-6461A/6420 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×149.225×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-6461A/6420 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 6461A/6420 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-6461A/6420 list two speeds, 2,500 and 3,400 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-6461A/6420 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "6461A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-6461a-6420", "6461a-6420", "6461A-6420", "4T-6461A-6420" ], "locale_variants": {} }, { "sku": "748S-742", "brand": "NTN", "manufacturer_designation": "NTN 4T-748S/742", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 150.089, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 289, "static_load_kN": 360, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-748S/742 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 76.2×150.089×44.45 mm (assembled width T), for a shaft of about 76.2 mm (3 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 748S sits in the pure-numeric inch family. Grease relubrication at the 2,400 r/min limiting speed targets the cone-rib contact; sustaining 3,200 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-748S/742: press the 742 cup square into the 150.089 mm seat first, then bring the 748S cone (on its 76.2 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-748S/742 run near 2,400 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 150.089 mm cup with a press sleeve; at 3650 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (150.089×44.45 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 748S/742 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 748S and 742; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full 748S/742 pair at ordering: the 748S cone also ships against sibling cups, and a cup from another reference changes the 44.45 mm assembled width and the rating.", "ABMA makes the 76.2×150.089 mm envelope interchangeable, not the ratings: NTN prints 289/360 kN for this execution and another make of the same number can differ in roller complement.", "The 289/360 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-748S/742; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-748S/742?", "a": "4T-748S/742 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 150.089 mm outside diameter and 44.45 mm assembled width T (5.909 × 1.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 289 kN, C0 360 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3650 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-748S/742 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 748S cone or the 742 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 289/360 kN ratings change with the cup." }, { "q": "What is the difference between 4T-748S/742 and a metric ISO 355 tapered bearing?", "a": "4T-748S/742 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×150.089×44.45 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-748S/742 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 748S/742 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-748S/742 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-748S/742 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "748S", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=188", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-748s-742", "748s-742", "748S-742", "4T-748S-742" ], "locale_variants": {} }, { "sku": "6576-6535", "brand": "NTN", "manufacturer_designation": "NTN 4T-6576/6535", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 161.925, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 340, "static_load_kN": 460, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3000, "weight_g": 5430, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 76.2 mm carrying combined radial and thrust load, NTN lists 4T-6576/6535, a single-row 4T tapered roller set of 340 kN C and 460 kN C0 inside the 161.925 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 6576 sits in the pure-numeric inch family. Speed planning uses both catalogue columns: grease 2,300 r/min is the mechanical ceiling for 4T-6576/6535, oil 3,000 r/min with circulating oil — a 700 r/min margin at this size. The printed 340/460 kN ratings belong to the assembled 6576+6535 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-6576/6535 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 161.925 mm cup with a press sleeve; at 5430 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 76.2 mm bore (161.925×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 6576/6535 reference at purchase.", "Do not confuse T (53.975 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 53.975 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 53.975 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 340/460 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-6576/6535; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-6576/6535?", "a": "4T-6576/6535 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 161.925 mm outside diameter and 53.975 mm assembled width T (6.375 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 340 kN, C0 460 kN, grease limiting speed 2,300 r/min, oil speed 3,000 r/min, mass about 5430 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-6576/6535 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 6576 cone or the 6535 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 340/460 kN ratings change with the cup." }, { "q": "What is the difference between 4T-6576/6535 and a metric ISO 355 tapered bearing?", "a": "4T-6576/6535 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×161.925×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-6576/6535 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 6576/6535 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-6576/6535 list two speeds, 2,300 and 3,000 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-6576/6535 at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "6576", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-6576-6535", "6576-6535", "4T-6576-6535" ], "locale_variants": {} }, { "sku": "H917840-H917810", "brand": "NTN", "manufacturer_designation": "NTN 4T-H917840/H917810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 180.975, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 360, "static_load_kN": 415, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2600, "weight_g": 6570, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-H917840/H917810 denotes the heavy H family of NTN inch tapered roller bearings — cone H917840 and cup H917810 delivered as a matched, separable pair of 76.2 mm bore and 180.975 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: H917840 identifies the cone of 76.2 mm (3 in) bore by catalogue lookup, and H917810 fixes the 180.975 mm OD. The 4.7 kN of dynamic capacity per millimetre of bore summarises the 360 kN rating over the 76.2 mm bore — sanity-check any interchange candidate against this ratio and the 53.975 mm T. Housing fitment sequence for 4T-H917840/H917810: press the H917810 cup square into the 180.975 mm seat first, then bring the H917840 cone (on its 76.2 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-H917840/H917810 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 180.975 mm cup with a press sleeve; at 6570 g a cocked ring brinells the raceway directly.", "The heavy H family at 76.2 mm bore (180.975×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full H917840/H917810 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 53.975 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Quote the full H917840/H917810 pair at ordering: the H917840 cone also ships against sibling cups, and a cup from another reference changes the 53.975 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 76.2 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 360/415 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-H917840/H917810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-H917840/H917810?", "a": "4T-H917840/H917810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 180.975 mm outside diameter and 53.975 mm assembled width T (7.125 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 360 kN, C0 415 kN, grease limiting speed 1,900 r/min, oil speed 2,600 r/min, mass about 6570 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-H917840/H917810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the H917840 cone or the H917810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 360/415 kN ratings change with the cup." }, { "q": "What is the difference between 4T-H917840/H917810 and a metric ISO 355 tapered bearing?", "a": "4T-H917840/H917810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×180.975×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-H917840/H917810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare H917840/H917810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-H917840/H917810 list two speeds, 1,900 and 2,600 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-H917840/H917810 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "H917840", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-h917840-h917810", "h917840-h917810", "H917840-H917810", "4T-H917840-H917810" ], "locale_variants": {} }, { "sku": "HH221430-HH221410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HH221430/HH221410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 76.2, "D_mm": 190.5, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 490, "static_load_kN": 610, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2600, "weight_g": 8710, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3 in (76.2 mm) shaft position as 4T-HH221430/HH221410: cone HH221430, cup HH221410, profiled rollers and a pressed-steel cage, rated 490 kN basic dynamic and 610 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote HH221430/HH221410 without it. Imperial cross-check for the drawing: 76.2×190.5×57.15 mm converts to 3 × 7.5 × 2.25 in; the ABMA envelope swaps with like-numbered inch parts but the 490/610 kN ratings are NTN-specific. Housing fitment sequence for 4T-HH221430/HH221410: press the HH221410 cup square into the 190.5 mm seat first, then bring the HH221430 cone (on its 76.2 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 76.2 mm cone with an induction heater (max 120 °C) and press the 190.5 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 76.2 mm cone by induction heating (max 120 °C) and the 190.5 mm cup with a press sleeve; at 8710 g a cocked ring brinells the raceway directly.", "The extra-heavy HH family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 76.2 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Replacing one half of an adjusted pair without resetting end play negates the 57.15 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-HH221430/HH221410 sets have no seals: a hub or gearbox needs external sealing or the 1,900 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 57.15 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 490/610 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HH221430/HH221410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HH221430/HH221410?", "a": "4T-HH221430/HH221410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 76.2 mm bore (3 in), 190.5 mm outside diameter and 57.15 mm assembled width T (7.5 × 2.25 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 490 kN, C0 610 kN, grease limiting speed 1,900 r/min, oil speed 2,600 r/min, mass about 8710 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HH221430/HH221410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HH221430 cone or the HH221410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 490/610 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HH221430/HH221410 and a metric ISO 355 tapered bearing?", "a": "4T-HH221430/HH221410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 76.2×190.5×57.15 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HH221430/HH221410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HH221430/HH221410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HH221430/HH221410 list two speeds, 1,900 and 2,600 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HH221430/HH221410 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HH221430", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hh221430-hh221410", "hh221430-hh221410", "HH221430-HH221410", "4T-HH221430-HH221410" ], "locale_variants": {} }, { "sku": "LM814849-LM814810", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM814849/LM814810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 77.788, "D_mm": 117.475, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 110, "static_load_kN": 162, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3900, "weight_g": 929, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-LM814849/LM814810 at 77.788 mm bore (3.063 in), 117.475 mm cup OD and 25.4 mm assembled T, with a grease limiting speed of 2,900 r/min and an oil ceiling of 3,900 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: LM814849 identifies the cone of 77.788 mm (3.063 in) bore by catalogue lookup, and LM814810 fixes the 117.475 mm OD. Catalogue mass of the 4T-LM814849/LM814810 cone-plus-cup set is 929 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-LM814849/LM814810: press the LM814810 cup square into the 117.475 mm seat first, then bring the LM814849 cone (on its 77.788 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-LM814849/LM814810 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 77.788 mm cone by induction heating (max 120 °C) and the 117.475 mm cup with a press sleeve; at 929 g a cocked ring brinells the raceway directly.", "The light-medium LM family at 77.788 mm bore (117.475×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM814849/LM814810 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of LM814849 and LM814810; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-LM814849/LM814810 near 2,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 25.4 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 110/162 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM814849/LM814810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM814849/LM814810?", "a": "4T-LM814849/LM814810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 77.788 mm bore (3.063 in), 117.475 mm outside diameter and 25.4 mm assembled width T (4.625 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 110 kN, C0 162 kN, grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 929 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM814849/LM814810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM814849 cone or the LM814810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 110/162 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM814849/LM814810 and a metric ISO 355 tapered bearing?", "a": "4T-LM814849/LM814810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 77.788×117.475×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM814849/LM814810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM814849/LM814810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM814849/LM814810 list two speeds, 2,900 and 3,900 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM814849/LM814810 at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM814849", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm814849-lm814810", "lm814849-lm814810", "LM814849-LM814810", "4T-LM814849-LM814810" ], "locale_variants": {} }, { "sku": "34306-34478-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-34306/34478", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 77.788, "D_mm": 121.442, "B_mm": 24.608, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 101, "static_load_kN": 127, "limiting_speed_rpm": 2900, "max_rpm": 2900, "speed_oil_rpm": 3800, "weight_g": 940, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-34306/34478 at 77.788 mm bore (3.063 in), 121.442 mm cup OD and 24.608 mm assembled T, with a grease limiting speed of 2,900 r/min and an oil ceiling of 3,800 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 34306/34478 without it. Selection: C 101 kN against C0 127 kN gives a C0/C ratio of 1.26 for the 77.788 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-34306/34478: press the 34478 cup square into the 121.442 mm seat first, then bring the 34306 cone (on its 77.788 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 77.788 mm cone with an induction heater (max 120 °C) and press the 121.442 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 77.788 mm cone by induction heating (max 120 °C) and the 121.442 mm cup with a press sleeve; at 940 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 77.788 mm bore (121.442×24.608 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 34306/34478 reference at purchase.", "Quote the full 34306/34478 pair at ordering: the 34306 cone also ships against sibling cups, and a cup from another reference changes the 24.608 mm assembled width and the rating.", "Open 4T-34306/34478 sets have no seals: a hub or gearbox needs external sealing or the 2,900 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 24.608 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 101/127 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-34306/34478; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-34306/34478?", "a": "4T-34306/34478 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 77.788 mm bore (3.063 in), 121.442 mm outside diameter and 24.608 mm assembled width T (4.781 × 0.969 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 101 kN, C0 127 kN, grease limiting speed 2,900 r/min, oil speed 3,800 r/min, mass about 940 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-34306/34478 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 34306 cone or the 34478 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 101/127 kN ratings change with the cup." }, { "q": "What is the difference between 4T-34306/34478 and a metric ISO 355 tapered bearing?", "a": "4T-34306/34478 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 77.788×121.442×24.608 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-34306/34478 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 34306/34478 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-34306/34478 list two speeds, 2,900 and 3,800 r/min?", "a": "The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-34306/34478 at 3,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "34306-34478", "equiv_brand": "SKF", "level": "partial", "note": "Same 77.788×121.442×24.608 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-34306-34478", "34306-34478", "4T-34306-34478", "34306-34478-NTN" ], "locale_variants": {} }, { "sku": "42690-42620-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-42690/42620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 77.788, "D_mm": 127, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 150, "static_load_kN": 194, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3700, "weight_g": 1240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.063 in (77.788 mm) shaft position as 4T-42690/42620: cone 42690, cup 42620, profiled rollers and a pressed-steel cage, rated 150 kN basic dynamic and 194 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 42690 sits in the pure-numeric inch family. The 1.9 kN of dynamic capacity per millimetre of bore summarises the 150 kN rating over the 77.788 mm bore — sanity-check any interchange candidate against this ratio and the 30.162 mm T. The printed 150/194 kN ratings belong to the assembled 42690+42620 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-42690/42620 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 77.788 mm cone by induction heating (max 120 °C) and the 127 mm cup with a press sleeve; at 1240 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 77.788 mm bore (127×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 42690/42620 reference at purchase.", "Never drive the 127 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "An unloaded 4T-42690/42620 near 2,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 150/194 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-42690/42620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-42690/42620?", "a": "4T-42690/42620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 77.788 mm bore (3.063 in), 127 mm outside diameter and 30.162 mm assembled width T (5 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 150 kN, C0 194 kN, grease limiting speed 2,800 r/min, oil speed 3,700 r/min, mass about 1240 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-42690/42620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 42690 cone or the 42620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 150/194 kN ratings change with the cup." }, { "q": "What is the difference between 4T-42690/42620 and a metric ISO 355 tapered bearing?", "a": "4T-42690/42620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 77.788×127×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-42690/42620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 42690/42620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-42690/42620 list two speeds, 2,800 and 3,700 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-42690/42620 at 3,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "42690-42620", "equiv_brand": "SKF", "level": "partial", "note": "Same 77.788×127×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-42690-42620", "42690-42620", "4T-42690-42620", "42690-42620-NTN" ], "locale_variants": {} }, { "sku": "495AS-493", "brand": "NTN", "manufacturer_designation": "NTN 4T-495AS/493", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 77.788, "D_mm": 136.525, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 143, "static_load_kN": 189, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1780, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-495AS/493 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 495AS/493 without it. Grease relubrication at the 2,600 r/min limiting speed targets the cone-rib contact; sustaining 3,500 r/min needs an oil supply directed at the large roller ends. Cup-side note for 493: within the pure-numeric inch family tables the 495AS cone is listed against several cup options, and it is the cup that fixes the 136.525 mm OD and the 30.162 mm assembled width — quote the full 495AS/493 pair, never the cone alone. Mount the 77.788 mm cone with an induction heater (max 120 °C) and press the 136.525 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 77.788 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 1780 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 77.788 mm bore (136.525×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 495AS/493 reference at purchase.", "Open 4T-495AS/493 sets have no seals: a hub or gearbox needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 77.788×136.525 mm envelope interchangeable, not the ratings: NTN prints 143/189 kN for this execution and another make of the same number can differ in roller complement.", "Inch and metric bores collide on paper — 77.788 mm is 3.063 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 143/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-495AS/493; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-495AS/493?", "a": "4T-495AS/493 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 77.788 mm bore (3.063 in), 136.525 mm outside diameter and 30.162 mm assembled width T (5.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 143 kN, C0 189 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1780 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-495AS/493 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 495AS cone or the 493 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 143/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-495AS/493 and a metric ISO 355 tapered bearing?", "a": "4T-495AS/493 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 77.788×136.525×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-495AS/493 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 495AS/493 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-495AS/493 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-495AS/493 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "495AS", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "495as-493", "4t-495as-493", "495AS-493", "4T-495AS-493" ], "locale_variants": {} }, { "sku": "H715348-H715311", "brand": "NTN", "manufacturer_designation": "NTN 4T-H715348/H715311", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 77.788, "D_mm": 136.525, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 248, "static_load_kN": 355, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 2840, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-H715348/H715311 is the NTN 4T catalogue entry for a 77.788×136.525×46.038 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-H715348/H715311 are separately stocked parts: a worn H715311 cup can be replaced against the existing H715348 cone, provided the new cup carries the identical reference — pairing across references changes the 46.038 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 46.038 mm T of each 4T-H715348/H715311 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for H715311: within the heavy H family tables the H715348 cone is listed against several cup options, and it is the cup that fixes the 136.525 mm OD and the 46.038 mm assembled width — quote the full H715348/H715311 pair, never the cone alone. Running clearance of 4T-H715348/H715311 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 77.788 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 2840 g a cocked ring brinells the raceway directly.", "The heavy H family at 77.788 mm bore (136.525×46.038 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full H715348/H715311 reference at purchase.", "Do not confuse T (46.038 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-H715348/H715311 sets have no seals: a hub or gearbox needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "ABMA makes the 77.788×136.525 mm envelope interchangeable, not the ratings: NTN prints 248/355 kN for this execution and another make of the same number can differ in roller complement.", "The 248/355 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-H715348/H715311; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-H715348/H715311?", "a": "4T-H715348/H715311 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 77.788 mm bore (3.063 in), 136.525 mm outside diameter and 46.038 mm assembled width T (5.375 × 1.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 248 kN, C0 355 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 2840 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-H715348/H715311 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the H715348 cone or the H715311 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 248/355 kN ratings change with the cup." }, { "q": "What is the difference between 4T-H715348/H715311 and a metric ISO 355 tapered bearing?", "a": "4T-H715348/H715311 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 77.788×136.525×46.038 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-H715348/H715311 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare H715348/H715311 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-H715348/H715311 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-H715348/H715311 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "H715348", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-h715348-h715311", "h715348-h715311", "H715348-H715311", "4T-H715348-H715311" ], "locale_variants": {} }, { "sku": "661-653", "brand": "NTN", "manufacturer_designation": "NTN 4T-661/653", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 79.375, "D_mm": 146.05, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 228, "static_load_kN": 295, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 2920, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 79.375 mm carrying combined radial and thrust load, NTN lists 4T-661/653, a single-row 4T tapered roller set of 228 kN C and 295 kN C0 inside the 146.05 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 661/653 without it. The 33.3 mm radial section over the 79.375 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-661/653: press the 653 cup square into the 146.05 mm seat first, then bring the 661 cone (on its 79.375 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-661/653 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 79.375 mm cone by induction heating (max 120 °C) and the 146.05 mm cup with a press sleeve; at 2920 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 79.375 mm bore (146.05×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 661/653 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 661 and 653; use undercut shoulders so the rings seat on the face, not on a radius.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Open 4T-661/653 sets have no seals: a hub or gearbox needs external sealing or the 2,500 r/min grease figure is meaningless once water reaches the cone rib.", "The 228/295 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-661/653; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-661/653?", "a": "4T-661/653 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 79.375 mm bore (3.125 in), 146.05 mm outside diameter and 41.275 mm assembled width T (5.75 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 228 kN, C0 295 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 2920 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-661/653 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 661 cone or the 653 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 228/295 kN ratings change with the cup." }, { "q": "What is the difference between 4T-661/653 and a metric ISO 355 tapered bearing?", "a": "4T-661/653 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 79.375×146.05×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-661/653 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 661/653 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-661/653 list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-661/653 at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "661", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-661-653", "661-653", "4T-661-653" ], "locale_variants": {} }, { "sku": "756A-752", "brand": "NTN", "manufacturer_designation": "NTN 4T-756A/752", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 79.375, "D_mm": 161.925, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 299, "static_load_kN": 385, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 4550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.125 in (79.375 mm) shaft position as 4T-756A/752: cone 756A, cup 752, profiled rollers and a pressed-steel cage, rated 299 kN basic dynamic and 385 kN static. Reading the designation: 4T-756A/752 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Catalogue mass of the 4T-756A/752 cone-plus-cup set is 4550 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 752: within the pure-numeric inch family tables the 756A cone is listed against several cup options, and it is the cup that fixes the 161.925 mm OD and the 47.625 mm assembled width — quote the full 756A/752 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-756A/752 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 79.375 mm cone by induction heating (max 120 °C) and the 161.925 mm cup with a press sleeve; at 4550 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 79.375 mm bore (161.925×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 756A/752 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 79.375 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 756A/752 pair at ordering: the 756A cone also ships against sibling cups, and a cup from another reference changes the 47.625 mm assembled width and the rating.", "Open 4T-756A/752 sets have no seals: a hub or gearbox needs external sealing or the 2,300 r/min grease figure is meaningless once water reaches the cone rib.", "The 299/385 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-756A/752; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-756A/752?", "a": "4T-756A/752 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 79.375 mm bore (3.125 in), 161.925 mm outside diameter and 47.625 mm assembled width T (6.375 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 299 kN, C0 385 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 4550 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-756A/752 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 756A cone or the 752 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 299/385 kN ratings change with the cup." }, { "q": "What is the difference between 4T-756A/752 and a metric ISO 355 tapered bearing?", "a": "4T-756A/752 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 79.375×161.925×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-756A/752 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 756A/752 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-756A/752 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-756A/752 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "756A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-756a-752", "756a-752", "756A-752", "4T-756A-752" ], "locale_variants": {} }, { "sku": "HH221431-HH221410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HH221431/HH221410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 79.375, "D_mm": 190.5, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 490, "static_load_kN": 610, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2600, "weight_g": 8520, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HH221431/HH221410 belongs to the NTN inch 4T tapered roller range (extra-heavy HH family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HH221431 identifies the cone of 79.375 mm (3.125 in) bore by catalogue lookup, and HH221410 fixes the 190.5 mm OD. Catalogue mass of the 4T-HH221431/HH221410 cone-plus-cup set is 8520 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 490/610 kN ratings belong to the assembled HH221431+HH221410 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-HH221431/HH221410 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 79.375 mm cone by induction heating (max 120 °C) and the 190.5 mm cup with a press sleeve; at 8520 g a cocked ring brinells the raceway directly.", "The extra-heavy HH family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 79.375 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "An unloaded 4T-HH221431/HH221410 near 1,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 79.375 mm is 3.125 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Replacing one half of an adjusted pair without resetting end play negates the 57.15 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 490/610 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HH221431/HH221410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HH221431/HH221410?", "a": "4T-HH221431/HH221410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 79.375 mm bore (3.125 in), 190.5 mm outside diameter and 57.15 mm assembled width T (7.5 × 2.25 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 490 kN, C0 610 kN, grease limiting speed 1,900 r/min, oil speed 2,600 r/min, mass about 8520 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HH221431/HH221410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HH221431 cone or the HH221410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 490/610 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HH221431/HH221410 and a metric ISO 355 tapered bearing?", "a": "4T-HH221431/HH221410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 79.375×190.5×57.15 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HH221431/HH221410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HH221431/HH221410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HH221431/HH221410 list two speeds, 1,900 and 2,600 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HH221431/HH221410 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HH221431", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hh221431-hh221410", "hh221431-hh221410", "HH221431-HH221410", "4T-HH221431-HH221410" ], "locale_variants": {} }, { "sku": "JM515649-JM515610", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM515649/JM515610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 80, "D_mm": 130, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 184, "static_load_kN": 249, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 1740, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JM515649/JM515610 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 80×130×35 mm (assembled width T), for a shaft of about 80 mm (3.15 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote JM515649/JM515610 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 35 mm T of each 4T-JM515649/JM515610 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-JM515649/JM515610: press the JM515610 cup square into the 130 mm seat first, then bring the JM515649 cone (on its 80 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-JM515649/JM515610 run near 2,700 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 80 mm cone by induction heating (max 120 °C) and the 130 mm cup with a press sleeve; at 1740 g a cocked ring brinells the raceway directly.", "The J-prefixed JM515649 code belongs to a metric-envelope inch family: its 80 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Inch and metric bores collide on paper — 80 mm is 3.15 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Replacing one half of an adjusted pair without resetting end play negates the 35 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 80 mm is 3.15 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 184/249 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM515649/JM515610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM515649/JM515610?", "a": "4T-JM515649/JM515610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 80 mm bore (3.15 in), 130 mm outside diameter and 35 mm assembled width T (5.118 × 1.378 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 184 kN, C0 249 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 1740 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM515649/JM515610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM515649 cone or the JM515610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 184/249 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM515649/JM515610 and a metric ISO 355 tapered bearing?", "a": "4T-JM515649/JM515610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 80×130×35 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM515649/JM515610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM515649/JM515610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM515649/JM515610 list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM515649/JM515610 at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM515649", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm515649-jm515610", "4t-jm515649-jm515610", "jm515649-jm515610", "JM515649-JM515610", "4T-JM515649-JM515610" ], "locale_variants": {} }, { "sku": "47681-47620", "brand": "NTN", "manufacturer_designation": "NTN 4T-47681/47620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 80.962, "D_mm": 133.35, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 170, "static_load_kN": 235, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1780, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-47681/47620 at 80.962 mm bore (3.187 in), 133.35 mm cup OD and 33.338 mm assembled T, with a grease limiting speed of 2,600 r/min and an oil ceiling of 3,500 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 47681/47620 without it. Imperial cross-check for the drawing: 80.962×133.35×33.338 mm converts to 3.187 × 5.25 × 1.313 in; the ABMA envelope swaps with like-numbered inch parts but the 170/235 kN ratings are NTN-specific. Housing fitment sequence for 4T-47681/47620: press the 47620 cup square into the 133.35 mm seat first, then bring the 47681 cone (on its 80.962 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Fillet radii must clear the chamfers of the 47681 cone and 47620 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 80.962 mm cone by induction heating (max 120 °C) and the 133.35 mm cup with a press sleeve; at 1780 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 80.962 mm bore (133.35×33.338 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 47681/47620 reference at purchase.", "An unloaded 4T-47681/47620 near 2,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (33.338 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Fit selection follows the rotating ring: a rotating cone on a 80.962 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 170/235 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-47681/47620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-47681/47620?", "a": "4T-47681/47620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 80.962 mm bore (3.187 in), 133.35 mm outside diameter and 33.338 mm assembled width T (5.25 × 1.313 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 170 kN, C0 235 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1780 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-47681/47620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 47681 cone or the 47620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 170/235 kN ratings change with the cup." }, { "q": "What is the difference between 4T-47681/47620 and a metric ISO 355 tapered bearing?", "a": "4T-47681/47620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 80.962×133.35×33.338 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-47681/47620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 47681/47620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-47681/47620 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-47681/47620 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "47681", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-47681-47620", "47681-47620", "4T-47681-47620" ], "locale_variants": {} }, { "sku": "496-493", "brand": "NTN", "manufacturer_designation": "NTN 4T-496/493", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 80.962, "D_mm": 136.525, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 143, "static_load_kN": 189, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 80.962 mm carrying combined radial and thrust load, NTN lists 4T-496/493, a single-row 4T tapered roller set of 143 kN C and 189 kN C0 inside the 136.525 mm OD cup. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 496/493 without it. Speed planning uses both catalogue columns: grease 2,600 r/min is the mechanical ceiling for 4T-496/493, oil 3,500 r/min with circulating oil — a 900 r/min margin at this size. The printed 143/189 kN ratings belong to the assembled 496+493 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 80.962 mm cone with an induction heater (max 120 °C) and press the 136.525 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 80.962 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 1690 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 80.962 mm bore (136.525×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 496/493 reference at purchase.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,500 r/min raises temperature and destroys the setting.", "Replacing one half of an adjusted pair without resetting end play negates the 30.162 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 143/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-496/493; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-496/493?", "a": "4T-496/493 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 80.962 mm bore (3.187 in), 136.525 mm outside diameter and 30.162 mm assembled width T (5.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 143 kN, C0 189 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1690 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-496/493 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 496 cone or the 493 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 143/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-496/493 and a metric ISO 355 tapered bearing?", "a": "4T-496/493 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 80.962×136.525×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-496/493 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 496/493 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-496/493 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-496/493 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "496", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-496-493", "496-493", "4T-496-493" ], "locale_variants": {} }, { "sku": "581-572", "brand": "NTN", "manufacturer_designation": "NTN 4T-581/572", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 80.962, "D_mm": 139.992, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 197, "static_load_kN": 265, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3400, "weight_g": 2250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-581/572 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 80.962×139.992×36.512 mm (assembled width T), for a shaft of about 80.962 mm (3.187 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 581/572 without it. Selection: C 197 kN against C0 265 kN gives a C0/C ratio of 1.35 for the 80.962 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 197/265 kN ratings belong to the assembled 581+572 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-581/572 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 80.962 mm cone by induction heating (max 120 °C) and the 139.992 mm cup with a press sleeve; at 2250 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 80.962 mm bore (139.992×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 581/572 reference at purchase.", "Open 4T-581/572 sets have no seals: a hub or gearbox needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "Shaft and housing fillets must clear the ring chamfers of 581 and 572; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 80.962 mm is 3.187 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 197/265 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-581/572; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-581/572?", "a": "4T-581/572 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 80.962 mm bore (3.187 in), 139.992 mm outside diameter and 36.512 mm assembled width T (5.511 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 197 kN, C0 265 kN, grease limiting speed 2,600 r/min, oil speed 3,400 r/min, mass about 2250 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-581/572 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 581 cone or the 572 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 197/265 kN ratings change with the cup." }, { "q": "What is the difference between 4T-581/572 and a metric ISO 355 tapered bearing?", "a": "4T-581/572 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 80.962×139.992×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-581/572 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 581/572 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-581/572 list two speeds, 2,600 and 3,400 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-581/572 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "581", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-581-572", "581-572", "4T-581-572" ], "locale_variants": {} }, { "sku": "740-742", "brand": "NTN", "manufacturer_designation": "NTN 4T-740/742", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 80.962, "D_mm": 150.089, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 289, "static_load_kN": 360, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 80.962 mm carrying combined radial and thrust load, NTN lists 4T-740/742, a single-row 4T tapered roller set of 289 kN C and 360 kN C0 inside the 150.089 mm OD cup. Cone and cup of 4T-740/742 are separately stocked parts: a worn 742 cup can be replaced against the existing 740 cone, provided the new cup carries the identical reference — pairing across references changes the 44.45 mm assembled width and the rating. The 34.6 mm radial section over the 80.962 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-740/742: press the 742 cup square into the 150.089 mm seat first, then bring the 740 cone (on its 80.962 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 80.962 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 80.962 mm cone by induction heating (max 120 °C) and the 150.089 mm cup with a press sleeve; at 3440 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 80.962 mm bore (150.089×44.45 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 740/742 reference at purchase.", "Open 4T-740/742 sets have no seals: a hub or gearbox needs external sealing or the 2,400 r/min grease figure is meaningless once water reaches the cone rib.", "Never drive the 150.089 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "An unloaded 4T-740/742 near 2,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 289/360 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-740/742; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-740/742?", "a": "4T-740/742 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 80.962 mm bore (3.187 in), 150.089 mm outside diameter and 44.45 mm assembled width T (5.909 × 1.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 289 kN, C0 360 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3440 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-740/742 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 740 cone or the 742 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 289/360 kN ratings change with the cup." }, { "q": "What is the difference between 4T-740/742 and a metric ISO 355 tapered bearing?", "a": "4T-740/742 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 80.962×150.089×44.45 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-740/742 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 740/742 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-740/742 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-740/742 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "740", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-740-742", "740-742", "4T-740-742" ], "locale_variants": {} }, { "sku": "27687-27620", "brand": "NTN", "manufacturer_designation": "NTN 4T-27687/27620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 125.412, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 163, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-27687/27620 at 82.55 mm bore (3.25 in), 125.412 mm cup OD and 25.4 mm assembled T, with a grease limiting speed of 2,700 r/min and an oil ceiling of 3,600 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 27687/27620 without it. Selection: C 113 kN against C0 163 kN gives a C0/C ratio of 1.44 for the 82.55 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 113/163 kN ratings belong to the assembled 27687+27620 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 82.55 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 125.412 mm cup with a press sleeve; at 1050 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (125.412×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 27687/27620 reference at purchase.", "An unloaded 4T-27687/27620 near 2,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Grease packs must leave free volume inside the 25.4 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,600 r/min raises temperature and destroys the setting.", "Open 4T-27687/27620 sets have no seals: a hub or gearbox needs external sealing or the 2,700 r/min grease figure is meaningless once water reaches the cone rib.", "The 113/163 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-27687/27620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-27687/27620?", "a": "4T-27687/27620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 125.412 mm outside diameter and 25.4 mm assembled width T (4.937 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 163 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 1050 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-27687/27620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 27687 cone or the 27620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/163 kN ratings change with the cup." }, { "q": "What is the difference between 4T-27687/27620 and a metric ISO 355 tapered bearing?", "a": "4T-27687/27620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×125.412×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-27687/27620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 27687/27620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-27687/27620 list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-27687/27620 at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "27687", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-27687-27620", "27687-27620", "4T-27687-27620" ], "locale_variants": {} }, { "sku": "47686-47620", "brand": "NTN", "manufacturer_designation": "NTN 4T-47686/47620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 133.35, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 170, "static_load_kN": 235, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1720, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 82.55 mm carrying combined radial and thrust load, NTN lists 4T-47686/47620, a single-row 4T tapered roller set of 170 kN C and 235 kN C0 inside the 133.35 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 47686 sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 33.338 mm T of each 4T-47686/47620 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-47686/47620: press the 47620 cup square into the 133.35 mm seat first, then bring the 47686 cone (on its 82.55 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-47686/47620 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 133.35 mm cup with a press sleeve; at 1720 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (133.35×33.338 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 47686/47620 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 47686 and 47620; use undercut shoulders so the rings seat on the face, not on a radius.", "Fit selection follows the rotating ring: a rotating cone on a 82.55 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (33.338 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 170/235 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-47686/47620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-47686/47620?", "a": "4T-47686/47620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 133.35 mm outside diameter and 33.338 mm assembled width T (5.25 × 1.313 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 170 kN, C0 235 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1720 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-47686/47620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 47686 cone or the 47620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 170/235 kN ratings change with the cup." }, { "q": "What is the difference between 4T-47686/47620 and a metric ISO 355 tapered bearing?", "a": "4T-47686/47620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×133.35×33.338 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-47686/47620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 47686/47620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-47686/47620 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-47686/47620 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "47686", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-47686-47620", "47686-47620", "4T-47686-47620" ], "locale_variants": {} }, { "sku": "HM516448-HM516410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM516448/HM516410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 133.35, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 196, "static_load_kN": 305, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 2160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM516448/HM516410 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-HM516448/HM516410 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the heavy-medium HM family lettering ties the pair to its boundary plan. Selection: C 196 kN against C0 305 kN gives a C0/C ratio of 1.56 for the 82.55 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for HM516410: within the heavy-medium HM family tables the HM516448 cone is listed against several cup options, and it is the cup that fixes the 133.35 mm OD and the 39.688 mm assembled width — quote the full HM516448/HM516410 pair, never the cone alone. Fillet radii must clear the chamfers of the HM516448 cone and HM516410 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 133.35 mm cup with a press sleeve; at 2160 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 82.55 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Shaft and housing fillets must clear the ring chamfers of HM516448 and HM516410; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full HM516448/HM516410 pair at ordering: the HM516448 cone also ships against sibling cups, and a cup from another reference changes the 39.688 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of HM516448 and HM516410; use undercut shoulders so the rings seat on the face, not on a radius.", "The 196/305 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM516448/HM516410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM516448/HM516410?", "a": "4T-HM516448/HM516410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 133.35 mm outside diameter and 39.688 mm assembled width T (5.25 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 196 kN, C0 305 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 2160 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM516448/HM516410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM516448 cone or the HM516410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 196/305 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM516448/HM516410 and a metric ISO 355 tapered bearing?", "a": "4T-HM516448/HM516410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×133.35×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM516448/HM516410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM516448/HM516410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM516448/HM516410 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM516448/HM516410 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM516448", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm516448-hm516410", "hm516448-hm516410", "HM516448-HM516410", "4T-HM516448-HM516410" ], "locale_variants": {} }, { "sku": "495-493", "brand": "NTN", "manufacturer_designation": "NTN 4T-495/493", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 136.525, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 143, "static_load_kN": 189, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1640, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-495/493 at 82.55 mm bore (3.25 in), 136.525 mm cup OD and 30.162 mm assembled T, with a grease limiting speed of 2,600 r/min and an oil ceiling of 3,500 r/min. Reading the designation: 4T-495/493 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Selection: C 143 kN against C0 189 kN gives a C0/C ratio of 1.32 for the 82.55 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 493: within the pure-numeric inch family tables the 495 cone is listed against several cup options, and it is the cup that fixes the 136.525 mm OD and the 30.162 mm assembled width — quote the full 495/493 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-495/493 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 1640 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (136.525×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 495/493 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 495 and 493; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of 495 and 493; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 30.162 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,500 r/min raises temperature and destroys the setting.", "The 143/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-495/493; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-495/493?", "a": "4T-495/493 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 136.525 mm outside diameter and 30.162 mm assembled width T (5.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 143 kN, C0 189 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1640 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-495/493 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 495 cone or the 493 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 143/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-495/493 and a metric ISO 355 tapered bearing?", "a": "4T-495/493 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×136.525×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-495/493 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 495/493 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-495/493 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-495/493 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "495", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-495-493", "495-493", "4T-495-493" ], "locale_variants": {} }, { "sku": "580-572-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-580/572", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 139.992, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 197, "static_load_kN": 265, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3400, "weight_g": 2190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-580/572 is the NTN 4T catalogue entry for a 82.55×139.992×36.512 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 580 sits in the pure-numeric inch family. Contact-angle geometry of the pure-numeric inch family gives 4T-580/572 its radial/axial load split — at 197/265 kN the static rating is about 1.35× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-580/572: press the 572 cup square into the 139.992 mm seat first, then bring the 580 cone (on its 82.55 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-580/572; reverse the fit logic when the cup rotates.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 139.992 mm cup with a press sleeve; at 2190 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (139.992×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 580/572 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 580 and 572; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of 580 and 572; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-580/572 near 2,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 197/265 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-580/572; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-580/572?", "a": "4T-580/572 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 139.992 mm outside diameter and 36.512 mm assembled width T (5.511 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 197 kN, C0 265 kN, grease limiting speed 2,600 r/min, oil speed 3,400 r/min, mass about 2190 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-580/572 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 580 cone or the 572 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 197/265 kN ratings change with the cup." }, { "q": "What is the difference between 4T-580/572 and a metric ISO 355 tapered bearing?", "a": "4T-580/572 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×139.992×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-580/572 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 580/572 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-580/572 list two speeds, 2,600 and 3,400 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-580/572 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "580-572", "equiv_brand": "SKF", "level": "partial", "note": "Same 82.55×139.992×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-580-572", "580-572", "4T-580-572", "580-572-NTN" ], "locale_variants": {} }, { "sku": "582-572", "brand": "NTN", "manufacturer_designation": "NTN 4T-582/572", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 139.992, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 197, "static_load_kN": 265, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3400, "weight_g": 2180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-582/572 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 582 sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 36.512 mm T of each 4T-582/572 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 572: within the pure-numeric inch family tables the 582 cone is listed against several cup options, and it is the cup that fixes the 139.992 mm OD and the 36.512 mm assembled width — quote the full 582/572 pair, never the cone alone. Mount the 82.55 mm cone with an induction heater (max 120 °C) and press the 139.992 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 139.992 mm cup with a press sleeve; at 2180 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (139.992×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 582/572 reference at purchase.", "Grease packs must leave free volume inside the 36.512 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,400 r/min raises temperature and destroys the setting.", "Replacing one half of an adjusted pair without resetting end play negates the 36.512 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 197/265 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-582/572; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-582/572?", "a": "4T-582/572 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 139.992 mm outside diameter and 36.512 mm assembled width T (5.511 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 197 kN, C0 265 kN, grease limiting speed 2,600 r/min, oil speed 3,400 r/min, mass about 2180 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-582/572 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 582 cone or the 572 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 197/265 kN ratings change with the cup." }, { "q": "What is the difference between 4T-582/572 and a metric ISO 355 tapered bearing?", "a": "4T-582/572 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×139.992×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-582/572 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 582/572 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-582/572 list two speeds, 2,600 and 3,400 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-582/572 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "582", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-582-572", "582-572", "4T-582-572" ], "locale_variants": {} }, { "sku": "663-653-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-663/653", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 146.05, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 228, "static_load_kN": 295, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 2790, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-663/653 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-663/653 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Speed planning uses both catalogue columns: grease 2,500 r/min is the mechanical ceiling for 4T-663/653, oil 3,300 r/min with circulating oil — a 800 r/min margin at this size. Housing fitment sequence for 4T-663/653: press the 653 cup square into the 146.05 mm seat first, then bring the 663 cone (on its 82.55 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Contact-pattern check with marking blue: a pattern biased to one roller end means the 82.55 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 146.05 mm cup with a press sleeve; at 2790 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (146.05×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 663/653 reference at purchase.", "Inch and metric bores collide on paper — 82.55 mm is 3.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Shaft and housing fillets must clear the ring chamfers of 663 and 653; use undercut shoulders so the rings seat on the face, not on a radius.", "Shaft and housing fillets must clear the ring chamfers of 663 and 653; use undercut shoulders so the rings seat on the face, not on a radius.", "The 228/295 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-663/653; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-663/653?", "a": "4T-663/653 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 146.05 mm outside diameter and 41.275 mm assembled width T (5.75 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 228 kN, C0 295 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 2790 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-663/653 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 663 cone or the 653 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 228/295 kN ratings change with the cup." }, { "q": "What is the difference between 4T-663/653 and a metric ISO 355 tapered bearing?", "a": "4T-663/653 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×146.05×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-663/653 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 663/653 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-663/653 list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-663/653 at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "663-653", "equiv_brand": "SKF", "level": "partial", "note": "Same 82.55×146.05×41.275 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "663-652", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-663 paired with a different cup (652): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-663-653", "663-653", "4T-663-653", "663-653-NTN" ], "locale_variants": {} }, { "sku": "749A-742-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-749A/742", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 150.089, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 289, "static_load_kN": 360, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-749A/742 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 82.55×150.089×44.45 mm (assembled width T), for a shaft of about 82.55 mm (3.25 in). Cone and cup of 4T-749A/742 are separately stocked parts: a worn 742 cup can be replaced against the existing 749A cone, provided the new cup carries the identical reference — pairing across references changes the 44.45 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 44.45 mm T of each 4T-749A/742 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-749A/742: press the 742 cup square into the 150.089 mm seat first, then bring the 749A cone (on its 82.55 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 82.55 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 150.089 mm cup with a press sleeve; at 3370 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (150.089×44.45 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 749A/742 reference at purchase.", "Inch and metric bores collide on paper — 82.55 mm is 3.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Never drive the 150.089 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "An unloaded 4T-749A/742 near 2,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 289/360 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-749A/742; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-749A/742?", "a": "4T-749A/742 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 150.089 mm outside diameter and 44.45 mm assembled width T (5.909 × 1.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 289 kN, C0 360 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3370 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-749A/742 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 749A cone or the 742 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 289/360 kN ratings change with the cup." }, { "q": "What is the difference between 4T-749A/742 and a metric ISO 355 tapered bearing?", "a": "4T-749A/742 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×150.089×44.45 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-749A/742 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 749A/742 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-749A/742 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-749A/742 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "749A-742", "equiv_brand": "SKF", "level": "partial", "note": "Same 82.55×150.089×44.45 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-749a-742", "749a-742", "749A-742", "4T-749A-742", "749A-742-NTN" ], "locale_variants": {} }, { "sku": "595-592A", "brand": "NTN", "manufacturer_designation": "NTN 4T-595/592A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 152.4, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 199, "static_load_kN": 279, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 3020, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-595/592A at 82.55 mm bore (3.25 in), 152.4 mm cup OD and 39.688 mm assembled T, with a grease limiting speed of 2,300 r/min and an oil ceiling of 3,100 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 595/592A without it. The 34.9 mm radial section over the 82.55 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-595/592A: press the 592A cup square into the 152.4 mm seat first, then bring the 595 cone (on its 82.55 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-595/592A run near 2,300 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 152.4 mm cup with a press sleeve; at 3020 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (152.4×39.688 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 595/592A reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 39.688 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Grease packs must leave free volume inside the 39.688 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,100 r/min raises temperature and destroys the setting.", "An unloaded 4T-595/592A near 2,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 199/279 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-595/592A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-595/592A?", "a": "4T-595/592A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 152.4 mm outside diameter and 39.688 mm assembled width T (6 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 199 kN, C0 279 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 3020 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-595/592A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 595 cone or the 592A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 199/279 kN ratings change with the cup." }, { "q": "What is the difference between 4T-595/592A and a metric ISO 355 tapered bearing?", "a": "4T-595/592A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×152.4×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-595/592A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 595/592A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-595/592A list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-595/592A at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "595", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-595-592a", "595-592a", "595-592A", "4T-595-592A" ], "locale_variants": {} }, { "sku": "663-652", "brand": "NTN", "manufacturer_designation": "NTN 4T-663/652", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 152.4, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 228, "static_load_kN": 295, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 3160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-663/652 at 82.55 mm bore (3.25 in), 152.4 mm cup OD and 41.275 mm assembled T, with a grease limiting speed of 2,500 r/min and an oil ceiling of 3,300 r/min. Cone and cup of 4T-663/652 are separately stocked parts: a worn 652 cup can be replaced against the existing 663 cone, provided the new cup carries the identical reference — pairing across references changes the 41.275 mm assembled width and the rating. The 34.9 mm radial section over the 82.55 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-663/652: press the 652 cup square into the 152.4 mm seat first, then bring the 663 cone (on its 82.55 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Fillet radii must clear the chamfers of the 663 cone and 652 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 152.4 mm cup with a press sleeve; at 3160 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (152.4×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 663/652 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 82.55 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 228/295 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-663/652; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-663/652?", "a": "4T-663/652 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 152.4 mm outside diameter and 41.275 mm assembled width T (6 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 228 kN, C0 295 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 3160 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-663/652 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 663 cone or the 652 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 228/295 kN ratings change with the cup." }, { "q": "What is the difference between 4T-663/652 and a metric ISO 355 tapered bearing?", "a": "4T-663/652 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×152.4×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-663/652 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 663/652 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-663/652 list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-663/652 at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "663-653", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "663-653-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same NTN cone 4T-663 paired with a different cup (653): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-663-652", "663-652", "4T-663-652" ], "locale_variants": {} }, { "sku": "6559C-6535", "brand": "NTN", "manufacturer_designation": "NTN 4T-6559C/6535", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 161.925, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 340, "static_load_kN": 460, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3000, "weight_g": 5100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.25 in (82.55 mm) shaft position as 4T-6559C/6535: cone 6559C, cup 6535, profiled rollers and a pressed-steel cage, rated 340 kN basic dynamic and 460 kN static. Cone and cup of 4T-6559C/6535 are separately stocked parts: a worn 6535 cup can be replaced against the existing 6559C cone, provided the new cup carries the identical reference — pairing across references changes the 53.975 mm assembled width and the rating. Grease relubrication at the 2,300 r/min limiting speed targets the cone-rib contact; sustaining 3,000 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-6559C/6535: press the 6535 cup square into the 161.925 mm seat first, then bring the 6559C cone (on its 82.55 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-6559C/6535 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 161.925 mm cup with a press sleeve; at 5100 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (161.925×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 6559C/6535 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 82.55 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (53.975 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Grease packs must leave free volume inside the 53.975 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,000 r/min raises temperature and destroys the setting.", "The 340/460 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-6559C/6535; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-6559C/6535?", "a": "4T-6559C/6535 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 161.925 mm outside diameter and 53.975 mm assembled width T (6.375 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 340 kN, C0 460 kN, grease limiting speed 2,300 r/min, oil speed 3,000 r/min, mass about 5100 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-6559C/6535 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 6559C cone or the 6535 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 340/460 kN ratings change with the cup." }, { "q": "What is the difference between 4T-6559C/6535 and a metric ISO 355 tapered bearing?", "a": "4T-6559C/6535 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×161.925×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-6559C/6535 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 6559C/6535 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-6559C/6535 list two speeds, 2,300 and 3,000 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-6559C/6535 at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "6559C", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-6559c-6535", "6559c-6535", "6559C-6535", "4T-6559C-6535" ], "locale_variants": {} }, { "sku": "757-752", "brand": "NTN", "manufacturer_designation": "NTN 4T-757/752", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 161.925, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 299, "static_load_kN": 385, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 4420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.25 in (82.55 mm) shaft position as 4T-757/752: cone 757, cup 752, profiled rollers and a pressed-steel cage, rated 299 kN basic dynamic and 385 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 757/752 without it. The 3.6 kN of dynamic capacity per millimetre of bore summarises the 299 kN rating over the 82.55 mm bore — sanity-check any interchange candidate against this ratio and the 47.625 mm T. Housing fitment sequence for 4T-757/752: press the 752 cup square into the 161.925 mm seat first, then bring the 757 cone (on its 82.55 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-757/752; reverse the fit logic when the cup rotates.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 161.925 mm cup with a press sleeve; at 4420 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (161.925×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 757/752 reference at purchase.", "Grease packs must leave free volume inside the 47.625 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,100 r/min raises temperature and destroys the setting.", "An unloaded 4T-757/752 near 2,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 82.55 mm is 3.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 299/385 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-757/752; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-757/752?", "a": "4T-757/752 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 161.925 mm outside diameter and 47.625 mm assembled width T (6.375 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 299 kN, C0 385 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 4420 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-757/752 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 757 cone or the 752 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 299/385 kN ratings change with the cup." }, { "q": "What is the difference between 4T-757/752 and a metric ISO 355 tapered bearing?", "a": "4T-757/752 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×161.925×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-757/752 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 757/752 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-757/752 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-757/752 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "757", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-757-752", "757-752", "4T-757-752" ], "locale_variants": {} }, { "sku": "842-832", "brand": "NTN", "manufacturer_designation": "NTN 4T-842/832", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 82.55, "D_mm": 168.275, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 375, "static_load_kN": 460, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 3000, "weight_g": 5470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 82.55 mm carrying combined radial and thrust load, NTN lists 4T-842/832, a single-row 4T tapered roller set of 375 kN C and 460 kN C0 inside the 168.275 mm OD cup. Cone and cup of 4T-842/832 are separately stocked parts: a worn 832 cup can be replaced against the existing 842 cone, provided the new cup carries the identical reference — pairing across references changes the 53.975 mm assembled width and the rating. Grease relubrication at the 2,200 r/min limiting speed targets the cone-rib contact; sustaining 3,000 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-842/832: press the 832 cup square into the 168.275 mm seat first, then bring the 842 cone (on its 82.55 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-842/832 run near 2,200 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 82.55 mm cone by induction heating (max 120 °C) and the 168.275 mm cup with a press sleeve; at 5470 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 82.55 mm bore (168.275×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 842/832 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 82.55 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 842/832 pair at ordering: the 842 cone also ships against sibling cups, and a cup from another reference changes the 53.975 mm assembled width and the rating.", "ABMA makes the 82.55×168.275 mm envelope interchangeable, not the ratings: NTN prints 375/460 kN for this execution and another make of the same number can differ in roller complement.", "The 375/460 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-842/832; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-842/832?", "a": "4T-842/832 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 82.55 mm bore (3.25 in), 168.275 mm outside diameter and 53.975 mm assembled width T (6.625 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 375 kN, C0 460 kN, grease limiting speed 2,200 r/min, oil speed 3,000 r/min, mass about 5470 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-842/832 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 842 cone or the 832 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 375/460 kN ratings change with the cup." }, { "q": "What is the difference between 4T-842/832 and a metric ISO 355 tapered bearing?", "a": "4T-842/832 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 82.55×168.275×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-842/832 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 842/832 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-842/832 list two speeds, 2,200 and 3,000 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-842/832 at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "842", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-842-832", "842-832", "4T-842-832" ], "locale_variants": {} }, { "sku": "27689-27620", "brand": "NTN", "manufacturer_designation": "NTN 4T-27689/27620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 83.345, "D_mm": 125.412, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 163, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 1060, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-27689/27620 at 83.345 mm bore (3.281 in), 125.412 mm cup OD and 25.4 mm assembled T, with a grease limiting speed of 2,700 r/min and an oil ceiling of 3,600 r/min. Cone and cup of 4T-27689/27620 are separately stocked parts: a worn 27620 cup can be replaced against the existing 27689 cone, provided the new cup carries the identical reference — pairing across references changes the 25.4 mm assembled width and the rating. Catalogue mass of the 4T-27689/27620 cone-plus-cup set is 1060 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 27620: within the pure-numeric inch family tables the 27689 cone is listed against several cup options, and it is the cup that fixes the 125.412 mm OD and the 25.4 mm assembled width — quote the full 27689/27620 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-27689/27620 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 83.345 mm cone by induction heating (max 120 °C) and the 125.412 mm cup with a press sleeve; at 1060 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 83.345 mm bore (125.412×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 27689/27620 reference at purchase.", "Grease packs must leave free volume inside the 25.4 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,600 r/min raises temperature and destroys the setting.", "Quote the full 27689/27620 pair at ordering: the 27689 cone also ships against sibling cups, and a cup from another reference changes the 25.4 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 83.345 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 113/163 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-27689/27620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-27689/27620?", "a": "4T-27689/27620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 83.345 mm bore (3.281 in), 125.412 mm outside diameter and 25.4 mm assembled width T (4.937 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 163 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 1060 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-27689/27620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 27689 cone or the 27620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/163 kN ratings change with the cup." }, { "q": "What is the difference between 4T-27689/27620 and a metric ISO 355 tapered bearing?", "a": "4T-27689/27620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 83.345×125.412×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-27689/27620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 27689/27620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-27689/27620 list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-27689/27620 at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "27689", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-27689-27620", "27689-27620", "4T-27689-27620" ], "locale_variants": {} }, { "sku": "27690-27620", "brand": "NTN", "manufacturer_designation": "NTN 4T-27690/27620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 83.345, "D_mm": 125.412, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 163, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 1030, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-27690/27620 is the NTN 4T catalogue entry for a 83.345×125.412×25.4 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 27690 identifies the cone of 83.345 mm (3.281 in) bore by catalogue lookup, and 27620 fixes the 125.412 mm OD. Catalogue mass of the 4T-27690/27620 cone-plus-cup set is 1030 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 27620: within the pure-numeric inch family tables the 27690 cone is listed against several cup options, and it is the cup that fixes the 125.412 mm OD and the 25.4 mm assembled width — quote the full 27690/27620 pair, never the cone alone. Mount the 83.345 mm cone with an induction heater (max 120 °C) and press the 125.412 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 83.345 mm cone by induction heating (max 120 °C) and the 125.412 mm cup with a press sleeve; at 1030 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 83.345 mm bore (125.412×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 27690/27620 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 83.345 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Fit selection follows the rotating ring: a rotating cone on a 83.345 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 83.345×125.412 mm envelope interchangeable, not the ratings: NTN prints 113/163 kN for this execution and another make of the same number can differ in roller complement.", "The 113/163 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-27690/27620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-27690/27620?", "a": "4T-27690/27620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 83.345 mm bore (3.281 in), 125.412 mm outside diameter and 25.4 mm assembled width T (4.937 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 163 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 1030 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-27690/27620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 27690 cone or the 27620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/163 kN ratings change with the cup." }, { "q": "What is the difference between 4T-27690/27620 and a metric ISO 355 tapered bearing?", "a": "4T-27690/27620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 83.345×125.412×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-27690/27620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 27690/27620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-27690/27620 list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-27690/27620 at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "27690", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-27690-27620", "27690-27620", "4T-27690-27620" ], "locale_variants": {} }, { "sku": "27691-27620", "brand": "NTN", "manufacturer_designation": "NTN 4T-27691/27620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 83.345, "D_mm": 125.412, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 113, "static_load_kN": 163, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 1040, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-27691/27620 at 83.345 mm bore (3.281 in), 125.412 mm cup OD and 25.4 mm assembled T, with a grease limiting speed of 2,700 r/min and an oil ceiling of 3,600 r/min. Cone and cup of 4T-27691/27620 are separately stocked parts: a worn 27620 cup can be replaced against the existing 27691 cone, provided the new cup carries the identical reference — pairing across references changes the 25.4 mm assembled width and the rating. The 1.4 kN of dynamic capacity per millimetre of bore summarises the 113 kN rating over the 83.345 mm bore — sanity-check any interchange candidate against this ratio and the 25.4 mm T. The printed 113/163 kN ratings belong to the assembled 27691+27620 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-27691/27620; reverse the fit logic when the cup rotates.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 83.345 mm cone by induction heating (max 120 °C) and the 125.412 mm cup with a press sleeve; at 1040 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 83.345 mm bore (125.412×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 27691/27620 reference at purchase.", "ABMA makes the 83.345×125.412 mm envelope interchangeable, not the ratings: NTN prints 113/163 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 27691/27620 pair at ordering: the 27691 cone also ships against sibling cups, and a cup from another reference changes the 25.4 mm assembled width and the rating.", "Never drive the 125.412 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 113/163 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-27691/27620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-27691/27620?", "a": "4T-27691/27620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 83.345 mm bore (3.281 in), 125.412 mm outside diameter and 25.4 mm assembled width T (4.937 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 113 kN, C0 163 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 1040 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-27691/27620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 27691 cone or the 27620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 113/163 kN ratings change with the cup." }, { "q": "What is the difference between 4T-27691/27620 and a metric ISO 355 tapered bearing?", "a": "4T-27691/27620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 83.345×125.412×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-27691/27620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 27691/27620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-27691/27620 list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-27691/27620 at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "27691", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=189", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-27691-27620", "27691-27620", "4T-27691-27620" ], "locale_variants": {} }, { "sku": "498-493", "brand": "NTN", "manufacturer_designation": "NTN 4T-498/493", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 84.138, "D_mm": 136.525, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 143, "static_load_kN": 189, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 84.138 mm carrying combined radial and thrust load, NTN lists 4T-498/493, a single-row 4T tapered roller set of 143 kN C and 189 kN C0 inside the 136.525 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 498 identifies the cone of 84.138 mm (3.313 in) bore by catalogue lookup, and 493 fixes the 136.525 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 30.162 mm T of each 4T-498/493 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 143/189 kN ratings belong to the assembled 498+493 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-498/493 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 84.138 mm cone by induction heating (max 120 °C) and the 136.525 mm cup with a press sleeve; at 1600 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 84.138 mm bore (136.525×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 498/493 reference at purchase.", "An unloaded 4T-498/493 near 2,600 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Quote the full 498/493 pair at ordering: the 498 cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "Open 4T-498/493 sets have no seals: a hub or gearbox needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 143/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-498/493; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-498/493?", "a": "4T-498/493 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 84.138 mm bore (3.313 in), 136.525 mm outside diameter and 30.162 mm assembled width T (5.375 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 143 kN, C0 189 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1600 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-498/493 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 498 cone or the 493 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 143/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-498/493 and a metric ISO 355 tapered bearing?", "a": "4T-498/493 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 84.138×136.525×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-498/493 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 498/493 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-498/493 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-498/493 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "498", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-498-493", "498-493", "4T-498-493" ], "locale_variants": {} }, { "sku": "JM716648-JM716610", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM716648/JM716610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 130, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 149, "static_load_kN": 214, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.346 in (85 mm) shaft position as 4T-JM716648/JM716610: cone JM716648, cup JM716610, profiled rollers and a pressed-steel cage, rated 149 kN basic dynamic and 214 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — JM716648 sits in the JM metric-envelope family. Catalogue mass of the 4T-JM716648/JM716610 cone-plus-cup set is 1370 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for JM716610: within the JM metric-envelope family tables the JM716648 cone is listed against several cup options, and it is the cup that fixes the 130 mm OD and the 30 mm assembled width — quote the full JM716648/JM716610 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-JM716648/JM716610 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the 130 mm cup with a press sleeve; at 1370 g a cocked ring brinells the raceway directly.", "The J-prefixed JM716648 code belongs to a metric-envelope inch family: its 85 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Open 4T-JM716648/JM716610 sets have no seals: a hub or gearbox needs external sealing or the 2,600 r/min grease figure is meaningless once water reaches the cone rib.", "Shaft and housing fillets must clear the ring chamfers of JM716648 and JM716610; use undercut shoulders so the rings seat on the face, not on a radius.", "ABMA makes the 85×130 mm envelope interchangeable, not the ratings: NTN prints 149/214 kN for this execution and another make of the same number can differ in roller complement.", "The 149/214 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM716648/JM716610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM716648/JM716610?", "a": "4T-JM716648/JM716610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 85 mm bore (3.346 in), 130 mm outside diameter and 30 mm assembled width T (5.118 × 1.181 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 149 kN, C0 214 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1370 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM716648/JM716610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM716648 cone or the JM716610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 149/214 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM716648/JM716610 and a metric ISO 355 tapered bearing?", "a": "4T-JM716648/JM716610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 85×130×30 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM716648/JM716610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM716648/JM716610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM716648/JM716610 list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM716648/JM716610 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM716648", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm716648-jm716610", "4t-jm716648-jm716610", "jm716648-jm716610", "JM716648-JM716610", "4T-JM716648-JM716610" ], "locale_variants": {} }, { "sku": "JHM516849-JHM516810", "brand": "NTN", "manufacturer_designation": "NTN 4T-JHM516849/JHM516810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 85, "D_mm": 140, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 218, "static_load_kN": 297, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3400, "weight_g": 2300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JHM516849/JHM516810 belongs to the NTN inch 4T tapered roller range (JHM heavy metric-envelope family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: JHM516849 identifies the cone of 85 mm (3.346 in) bore by catalogue lookup, and JHM516810 fixes the 140 mm OD. The 27.5 mm radial section over the 85 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for JHM516810: within the JHM heavy metric-envelope family tables the JHM516849 cone is listed against several cup options, and it is the cup that fixes the 140 mm OD and the 39 mm assembled width — quote the full JHM516849/JHM516810 pair, never the cone alone. Mount the 85 mm cone with an induction heater (max 120 °C) and press the 140 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 85 mm cone by induction heating (max 120 °C) and the 140 mm cup with a press sleeve; at 2300 g a cocked ring brinells the raceway directly.", "The J-prefixed JHM516849 code belongs to a metric-envelope inch family: its 85 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "ABMA makes the 85×140 mm envelope interchangeable, not the ratings: NTN prints 218/297 kN for this execution and another make of the same number can differ in roller complement.", "Grease packs must leave free volume inside the 39 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,400 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 85 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 218/297 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JHM516849/JHM516810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JHM516849/JHM516810?", "a": "4T-JHM516849/JHM516810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 85 mm bore (3.346 in), 140 mm outside diameter and 39 mm assembled width T (5.512 × 1.535 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 218 kN, C0 297 kN, grease limiting speed 2,500 r/min, oil speed 3,400 r/min, mass about 2300 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JHM516849/JHM516810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JHM516849 cone or the JHM516810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 218/297 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JHM516849/JHM516810 and a metric ISO 355 tapered bearing?", "a": "4T-JHM516849/JHM516810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 85×140×39 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JHM516849/JHM516810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JHM516849/JHM516810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JHM516849/JHM516810 list two speeds, 2,500 and 3,400 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JHM516849/JHM516810 at 3,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JHM516849", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jhm516849-jhm516810", "4t-jhm516849-jhm516810", "jhm516849-jhm516810", "JHM516849-JHM516810", "4T-JHM516849-JHM516810" ], "locale_variants": {} }, { "sku": "749-742", "brand": "NTN", "manufacturer_designation": "NTN 4T-749/742", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 85.026, "D_mm": 150.089, "B_mm": 44.45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 289, "static_load_kN": 360, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 3240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-749/742 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-749/742 are separately stocked parts: a worn 742 cup can be replaced against the existing 749 cone, provided the new cup carries the identical reference — pairing across references changes the 44.45 mm assembled width and the rating. Grease relubrication at the 2,400 r/min limiting speed targets the cone-rib contact; sustaining 3,200 r/min needs an oil supply directed at the large roller ends. Cup-side note for 742: within the pure-numeric inch family tables the 749 cone is listed against several cup options, and it is the cup that fixes the 150.089 mm OD and the 44.45 mm assembled width — quote the full 749/742 pair, never the cone alone. Mount the 85.026 mm cone with an induction heater (max 120 °C) and press the 150.089 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 85.026 mm cone by induction heating (max 120 °C) and the 150.089 mm cup with a press sleeve; at 3240 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 85.026 mm bore (150.089×44.45 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 749/742 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 749 and 742; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 44.45 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,200 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 85.026 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 289/360 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-749/742; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-749/742?", "a": "4T-749/742 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 85.026 mm bore (3.347 in), 150.089 mm outside diameter and 44.45 mm assembled width T (5.909 × 1.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 289 kN, C0 360 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 3240 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-749/742 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 749 cone or the 742 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 289/360 kN ratings change with the cup." }, { "q": "What is the difference between 4T-749/742 and a metric ISO 355 tapered bearing?", "a": "4T-749/742 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 85.026×150.089×44.45 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-749/742 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 749/742 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-749/742 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-749/742 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "749", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-749-742", "749-742", "4T-749-742" ], "locale_variants": {} }, { "sku": "497-492A-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-497/492A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 85.725, "D_mm": 133.35, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 143, "static_load_kN": 189, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 1430, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 85.725 mm carrying combined radial and thrust load, NTN lists 4T-497/492A, a single-row 4T tapered roller set of 143 kN C and 189 kN C0 inside the 133.35 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 497 identifies the cone of 85.725 mm (3.375 in) bore by catalogue lookup, and 492A fixes the 133.35 mm OD. Selection: C 143 kN against C0 189 kN gives a C0/C ratio of 1.32 for the 85.725 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 492A: within the pure-numeric inch family tables the 497 cone is listed against several cup options, and it is the cup that fixes the 133.35 mm OD and the 30.162 mm assembled width — quote the full 497/492A pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 85.725 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 85.725 mm cone by induction heating (max 120 °C) and the 133.35 mm cup with a press sleeve; at 1430 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 85.725 mm bore (133.35×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 497/492A reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 85.725 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 497/492A pair at ordering: the 497 cone also ships against sibling cups, and a cup from another reference changes the 30.162 mm assembled width and the rating.", "Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 143/189 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-497/492A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-497/492A?", "a": "4T-497/492A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 85.725 mm bore (3.375 in), 133.35 mm outside diameter and 30.162 mm assembled width T (5.25 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 143 kN, C0 189 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 1430 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-497/492A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 497 cone or the 492A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 143/189 kN ratings change with the cup." }, { "q": "What is the difference between 4T-497/492A and a metric ISO 355 tapered bearing?", "a": "4T-497/492A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 85.725×133.35×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-497/492A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 497/492A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-497/492A list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-497/492A at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "497-492A", "equiv_brand": "SKF", "level": "partial", "note": "Same 85.725×133.35×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "497-492a", "4t-497-492a", "497-492A", "4T-497-492A", "497-492A-NTN" ], "locale_variants": {} }, { "sku": "HM617049-HM617010", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM617049/HM617010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 85.725, "D_mm": 142.138, "B_mm": 42.862, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 240, "static_load_kN": 350, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 2710, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 85.725 mm carrying combined radial and thrust load, NTN lists 4T-HM617049/HM617010, a single-row 4T tapered roller set of 240 kN C and 350 kN C0 inside the 142.138 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HM617049 identifies the cone of 85.725 mm (3.375 in) bore by catalogue lookup, and HM617010 fixes the 142.138 mm OD. Catalogue mass of the 4T-HM617049/HM617010 cone-plus-cup set is 2710 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-HM617049/HM617010: press the HM617010 cup square into the 142.138 mm seat first, then bring the HM617049 cone (on its 85.725 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-HM617049/HM617010 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 85.725 mm cone by induction heating (max 120 °C) and the 142.138 mm cup with a press sleeve; at 2710 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 85.725 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Fit selection follows the rotating ring: a rotating cone on a 85.725 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of HM617049 and HM617010; use undercut shoulders so the rings seat on the face, not on a radius.", "Inch and metric bores collide on paper — 85.725 mm is 3.375 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 240/350 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM617049/HM617010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM617049/HM617010?", "a": "4T-HM617049/HM617010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 85.725 mm bore (3.375 in), 142.138 mm outside diameter and 42.862 mm assembled width T (5.596 × 1.687 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 240 kN, C0 350 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 2710 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM617049/HM617010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM617049 cone or the HM617010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 240/350 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM617049/HM617010 and a metric ISO 355 tapered bearing?", "a": "4T-HM617049/HM617010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 85.725×142.138×42.862 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM617049/HM617010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM617049/HM617010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM617049/HM617010 list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM617049/HM617010 at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM617049", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm617049-hm617010", "hm617049-hm617010", "HM617049-HM617010", "4T-HM617049-HM617010" ], "locale_variants": {} }, { "sku": "665-653-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-665/653", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 85.725, "D_mm": 146.05, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 228, "static_load_kN": 295, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 2650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-665/653 is the NTN 4T catalogue entry for a 85.725×146.05×41.275 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-665/653 are separately stocked parts: a worn 653 cup can be replaced against the existing 665 cone, provided the new cup carries the identical reference — pairing across references changes the 41.275 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 2,500 r/min is the mechanical ceiling for 4T-665/653, oil 3,300 r/min with circulating oil — a 800 r/min margin at this size. Cup-side note for 653: within the pure-numeric inch family tables the 665 cone is listed against several cup options, and it is the cup that fixes the 146.05 mm OD and the 41.275 mm assembled width — quote the full 665/653 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-665/653 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 85.725 mm cone by induction heating (max 120 °C) and the 146.05 mm cup with a press sleeve; at 2650 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 85.725 mm bore (146.05×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 665/653 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 85.725 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Quote the full 665/653 pair at ordering: the 665 cone also ships against sibling cups, and a cup from another reference changes the 41.275 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 85.725 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 228/295 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-665/653; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-665/653?", "a": "4T-665/653 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 85.725 mm bore (3.375 in), 146.05 mm outside diameter and 41.275 mm assembled width T (5.75 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 228 kN, C0 295 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 2650 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-665/653 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 665 cone or the 653 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 228/295 kN ratings change with the cup." }, { "q": "What is the difference between 4T-665/653 and a metric ISO 355 tapered bearing?", "a": "4T-665/653 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 85.725×146.05×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-665/653 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 665/653 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-665/653 list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-665/653 at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "665-653", "equiv_brand": "SKF", "level": "partial", "note": "Same 85.725×146.05×41.275 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-665-653", "665-653", "4T-665-653", "665-653-NTN" ], "locale_variants": {} }, { "sku": "596-592A", "brand": "NTN", "manufacturer_designation": "NTN 4T-596/592A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 85.725, "D_mm": 152.4, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 199, "static_load_kN": 279, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 2900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.375 in (85.725 mm) shaft position as 4T-596/592A: cone 596, cup 592A, profiled rollers and a pressed-steel cage, rated 199 kN basic dynamic and 279 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 596 identifies the cone of 85.725 mm (3.375 in) bore by catalogue lookup, and 592A fixes the 152.4 mm OD. Speed planning uses both catalogue columns: grease 2,300 r/min is the mechanical ceiling for 4T-596/592A, oil 3,100 r/min with circulating oil — a 800 r/min margin at this size. Cup-side note for 592A: within the pure-numeric inch family tables the 596 cone is listed against several cup options, and it is the cup that fixes the 152.4 mm OD and the 39.688 mm assembled width — quote the full 596/592A pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-596/592A pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 85.725 mm cone by induction heating (max 120 °C) and the 152.4 mm cup with a press sleeve; at 2900 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 85.725 mm bore (152.4×39.688 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 596/592A reference at purchase.", "An unloaded 4T-596/592A near 2,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 85.725 mm is 3.375 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Replacing one half of an adjusted pair without resetting end play negates the 39.688 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 199/279 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-596/592A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-596/592A?", "a": "4T-596/592A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 85.725 mm bore (3.375 in), 152.4 mm outside diameter and 39.688 mm assembled width T (6 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 199 kN, C0 279 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 2900 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-596/592A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 596 cone or the 592A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 199/279 kN ratings change with the cup." }, { "q": "What is the difference between 4T-596/592A and a metric ISO 355 tapered bearing?", "a": "4T-596/592A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 85.725×152.4×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-596/592A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 596/592A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-596/592A list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-596/592A at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "596", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-596-592a", "596-592a", "596-592A", "4T-596-592A" ], "locale_variants": {} }, { "sku": "758-752", "brand": "NTN", "manufacturer_designation": "NTN 4T-758/752", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 85.725, "D_mm": 161.925, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 299, "static_load_kN": 385, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 4260, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-758/752 is the NTN 4T catalogue entry for a 85.725×161.925×47.625 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 758 sits in the pure-numeric inch family. Grease relubrication at the 2,300 r/min limiting speed targets the cone-rib contact; sustaining 3,100 r/min needs an oil supply directed at the large roller ends. Cup-side note for 752: within the pure-numeric inch family tables the 758 cone is listed against several cup options, and it is the cup that fixes the 161.925 mm OD and the 47.625 mm assembled width — quote the full 758/752 pair, never the cone alone. Running clearance of 4T-758/752 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 85.725 mm cone by induction heating (max 120 °C) and the 161.925 mm cup with a press sleeve; at 4260 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 85.725 mm bore (161.925×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 758/752 reference at purchase.", "Never drive the 161.925 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (47.625 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Grease packs must leave free volume inside the 47.625 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,100 r/min raises temperature and destroys the setting.", "The 299/385 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-758/752; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-758/752?", "a": "4T-758/752 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 85.725 mm bore (3.375 in), 161.925 mm outside diameter and 47.625 mm assembled width T (6.375 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 299 kN, C0 385 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 4260 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-758/752 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 758 cone or the 752 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 299/385 kN ratings change with the cup." }, { "q": "What is the difference between 4T-758/752 and a metric ISO 355 tapered bearing?", "a": "4T-758/752 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 85.725×161.925×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-758/752 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 758/752 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-758/752 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-758/752 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "758", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-758-752", "758-752", "4T-758-752" ], "locale_variants": {} }, { "sku": "42346-42584", "brand": "NTN", "manufacturer_designation": "NTN 4T-42346/42584", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 87.96, "D_mm": 148.43, "B_mm": 28.575, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 215, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 1980, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.463 in (87.96 mm) shaft position as 4T-42346/42584: cone 42346, cup 42584, profiled rollers and a pressed-steel cage, rated 153 kN basic dynamic and 215 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 42346 identifies the cone of 87.96 mm (3.463 in) bore by catalogue lookup, and 42584 fixes the 148.43 mm OD. Catalogue mass of the 4T-42346/42584 cone-plus-cup set is 1980 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 153/215 kN ratings belong to the assembled 42346+42584 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-42346/42584 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 87.96 mm cone by induction heating (max 120 °C) and the 148.43 mm cup with a press sleeve; at 1980 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 87.96 mm bore (148.43×28.575 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 42346/42584 reference at purchase.", "Inch and metric bores collide on paper — 87.96 mm is 3.463 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "ABMA makes the 87.96×148.43 mm envelope interchangeable, not the ratings: NTN prints 153/215 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-42346/42584 near 2,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 153/215 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-42346/42584; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-42346/42584?", "a": "4T-42346/42584 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 87.96 mm bore (3.463 in), 148.43 mm outside diameter and 28.575 mm assembled width T (5.844 × 1.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 215 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 1980 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-42346/42584 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 42346 cone or the 42584 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/215 kN ratings change with the cup." }, { "q": "What is the difference between 4T-42346/42584 and a metric ISO 355 tapered bearing?", "a": "4T-42346/42584 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 87.96×148.43×28.575 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-42346/42584 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 42346/42584 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-42346/42584 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-42346/42584 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "42346", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-42346-42584", "42346-42584", "4T-42346-42584" ], "locale_variants": {} }, { "sku": "LL217849-LL217810", "brand": "NTN", "manufacturer_designation": "NTN 4T-LL217849/LL217810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 88.9, "D_mm": 121.442, "B_mm": 15.083, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 63, "static_load_kN": 88, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3600, "weight_g": 452, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-LL217849/LL217810 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 88.9×121.442×15.083 mm (assembled width T), for a shaft of about 88.9 mm (3.5 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: LL217849 identifies the cone of 88.9 mm (3.5 in) bore by catalogue lookup, and LL217810 fixes the 121.442 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 15.083 mm T of each 4T-LL217849/LL217810 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 63/88 kN ratings belong to the assembled LL217849+LL217810 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-LL217849/LL217810 run near 2,700 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 88.9 mm cone by induction heating (max 120 °C) and the 121.442 mm cup with a press sleeve; at 452 g a cocked ring brinells the raceway directly.", "The extra-light LL family at 88.9 mm bore (121.442×15.083 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LL217849/LL217810 reference at purchase.", "Inch and metric bores collide on paper — 88.9 mm is 3.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-LL217849/LL217810 sets have no seals: a hub or gearbox needs external sealing or the 2,700 r/min grease figure is meaningless once water reaches the cone rib.", "Open 4T-LL217849/LL217810 sets have no seals: a hub or gearbox needs external sealing or the 2,700 r/min grease figure is meaningless once water reaches the cone rib.", "The 63/88 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LL217849/LL217810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LL217849/LL217810?", "a": "4T-LL217849/LL217810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 88.9 mm bore (3.5 in), 121.442 mm outside diameter and 15.083 mm assembled width T (4.781 × 0.594 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 63 kN, C0 88 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 452 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LL217849/LL217810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LL217849 cone or the LL217810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 63/88 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LL217849/LL217810 and a metric ISO 355 tapered bearing?", "a": "4T-LL217849/LL217810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 88.9×121.442×15.083 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LL217849/LL217810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LL217849/LL217810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LL217849/LL217810 list two speeds, 2,700 and 3,600 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LL217849/LL217810 at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LL217849", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-ll217849-ll217810", "ll217849-ll217810", "LL217849-LL217810", "4T-LL217849-LL217810" ], "locale_variants": {} }, { "sku": "L217849-L217810", "brand": "NTN", "manufacturer_designation": "NTN 4T-L217849/L217810", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 88.9, "D_mm": 123.825, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 89, "static_load_kN": 141, "limiting_speed_rpm": 2700, "max_rpm": 2700, "speed_oil_rpm": 3500, "weight_g": 737, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 88.9 mm carrying combined radial and thrust load, NTN lists 4T-L217849/L217810, a single-row 4T tapered roller set of 89 kN C and 141 kN C0 inside the 123.825 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — L217849 sits in the light L family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 20.638 mm T of each 4T-L217849/L217810 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-L217849/L217810: press the L217810 cup square into the 123.825 mm seat first, then bring the L217849 cone (on its 88.9 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Contact-pattern check with marking blue: a pattern biased to one roller end means the 88.9 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 88.9 mm cone by induction heating (max 120 °C) and the 123.825 mm cup with a press sleeve; at 737 g a cocked ring brinells the raceway directly.", "The light L family at 88.9 mm bore (123.825×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L217849/L217810 reference at purchase.", "Grease packs must leave free volume inside the 20.638 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,500 r/min raises temperature and destroys the setting.", "ABMA makes the 88.9×123.825 mm envelope interchangeable, not the ratings: NTN prints 89/141 kN for this execution and another make of the same number can differ in roller complement.", "Grease packs must leave free volume inside the 20.638 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,500 r/min raises temperature and destroys the setting.", "The 89/141 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L217849/L217810; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L217849/L217810?", "a": "4T-L217849/L217810 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 88.9 mm bore (3.5 in), 123.825 mm outside diameter and 20.638 mm assembled width T (4.875 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 89 kN, C0 141 kN, grease limiting speed 2,700 r/min, oil speed 3,500 r/min, mass about 737 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L217849/L217810 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L217849 cone or the L217810 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 89/141 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L217849/L217810 and a metric ISO 355 tapered bearing?", "a": "4T-L217849/L217810 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 88.9×123.825×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L217849/L217810 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L217849/L217810 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L217849/L217810 list two speeds, 2,700 and 3,500 r/min?", "a": "The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L217849/L217810 at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L217849", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l217849-l217810", "l217849-l217810", "L217849-L217810", "4T-L217849-L217810" ], "locale_variants": {} }, { "sku": "42350-42584", "brand": "NTN", "manufacturer_designation": "NTN 4T-42350/42584", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 88.9, "D_mm": 148.43, "B_mm": 28.575, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 215, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.5 in (88.9 mm) shaft position as 4T-42350/42584: cone 42350, cup 42584, profiled rollers and a pressed-steel cage, rated 153 kN basic dynamic and 215 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 42350 sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 28.575 mm T of each 4T-42350/42584 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 153/215 kN ratings belong to the assembled 42350+42584 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 88.9 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 88.9 mm cone by induction heating (max 120 °C) and the 148.43 mm cup with a press sleeve; at 1950 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 88.9 mm bore (148.43×28.575 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 42350/42584 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 88.9 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Grease packs must leave free volume inside the 28.575 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,100 r/min raises temperature and destroys the setting.", "Replacing one half of an adjusted pair without resetting end play negates the 28.575 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 153/215 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-42350/42584; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-42350/42584?", "a": "4T-42350/42584 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 88.9 mm bore (3.5 in), 148.43 mm outside diameter and 28.575 mm assembled width T (5.844 × 1.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 215 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 1950 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-42350/42584 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 42350 cone or the 42584 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/215 kN ratings change with the cup." }, { "q": "What is the difference between 4T-42350/42584 and a metric ISO 355 tapered bearing?", "a": "4T-42350/42584 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 88.9×148.43×28.575 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-42350/42584 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 42350/42584 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-42350/42584 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-42350/42584 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "42350", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-42350-42584", "42350-42584", "4T-42350-42584" ], "locale_variants": {} }, { "sku": "593-592A-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-593/592A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 88.9, "D_mm": 152.4, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 199, "static_load_kN": 279, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 2770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-593/592A belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 593 identifies the cone of 88.9 mm (3.5 in) bore by catalogue lookup, and 592A fixes the 152.4 mm OD. Imperial cross-check for the drawing: 88.9×152.4×39.688 mm converts to 3.5 × 6 × 1.563 in; the ABMA envelope swaps with like-numbered inch parts but the 199/279 kN ratings are NTN-specific. Housing fitment sequence for 4T-593/592A: press the 592A cup square into the 152.4 mm seat first, then bring the 593 cone (on its 88.9 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-593/592A pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 88.9 mm cone by induction heating (max 120 °C) and the 152.4 mm cup with a press sleeve; at 2770 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 88.9 mm bore (152.4×39.688 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 593/592A reference at purchase.", "ABMA makes the 88.9×152.4 mm envelope interchangeable, not the ratings: NTN prints 199/279 kN for this execution and another make of the same number can differ in roller complement.", "Open 4T-593/592A sets have no seals: a hub or gearbox needs external sealing or the 2,300 r/min grease figure is meaningless once water reaches the cone rib.", "Inch and metric bores collide on paper — 88.9 mm is 3.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 199/279 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-593/592A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-593/592A?", "a": "4T-593/592A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 88.9 mm bore (3.5 in), 152.4 mm outside diameter and 39.688 mm assembled width T (6 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 199 kN, C0 279 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 2770 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-593/592A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 593 cone or the 592A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 199/279 kN ratings change with the cup." }, { "q": "What is the difference between 4T-593/592A and a metric ISO 355 tapered bearing?", "a": "4T-593/592A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 88.9×152.4×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-593/592A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 593/592A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-593/592A list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-593/592A at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "593-592A", "equiv_brand": "SKF", "level": "partial", "note": "Same 88.9×152.4×39.688 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-593-592a", "593-592a", "593-592A", "4T-593-592A", "593-592A-NTN" ], "locale_variants": {} }, { "sku": "6580-6535-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-6580/6535", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 88.9, "D_mm": 161.925, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 340, "static_load_kN": 460, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3000, "weight_g": 4720, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-6580/6535 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 88.9×161.925×53.975 mm (assembled width T), for a shaft of about 88.9 mm (3.5 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 6580 identifies the cone of 88.9 mm (3.5 in) bore by catalogue lookup, and 6535 fixes the 161.925 mm OD. Speed planning uses both catalogue columns: grease 2,300 r/min is the mechanical ceiling for 4T-6580/6535, oil 3,000 r/min with circulating oil — a 700 r/min margin at this size. Housing fitment sequence for 4T-6580/6535: press the 6535 cup square into the 161.925 mm seat first, then bring the 6580 cone (on its 88.9 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 88.9 mm cone with an induction heater (max 120 °C) and press the 161.925 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 88.9 mm cone by induction heating (max 120 °C) and the 161.925 mm cup with a press sleeve; at 4720 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 88.9 mm bore (161.925×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 6580/6535 reference at purchase.", "ABMA makes the 88.9×161.925 mm envelope interchangeable, not the ratings: NTN prints 340/460 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 88.9×161.925 mm envelope interchangeable, not the ratings: NTN prints 340/460 kN for this execution and another make of the same number can differ in roller complement.", "Inch and metric bores collide on paper — 88.9 mm is 3.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 340/460 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-6580/6535; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-6580/6535?", "a": "4T-6580/6535 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 88.9 mm bore (3.5 in), 161.925 mm outside diameter and 53.975 mm assembled width T (6.375 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 340 kN, C0 460 kN, grease limiting speed 2,300 r/min, oil speed 3,000 r/min, mass about 4720 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-6580/6535 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 6580 cone or the 6535 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 340/460 kN ratings change with the cup." }, { "q": "What is the difference between 4T-6580/6535 and a metric ISO 355 tapered bearing?", "a": "4T-6580/6535 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 88.9×161.925×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-6580/6535 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 6580/6535 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-6580/6535 list two speeds, 2,300 and 3,000 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-6580/6535 at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "6580-6535", "equiv_brand": "SKF", "level": "partial", "note": "Same 88.9×161.925×53.975 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-6580-6535", "6580-6535", "4T-6580-6535", "6580-6535-NTN" ], "locale_variants": {} }, { "sku": "759-752", "brand": "NTN", "manufacturer_designation": "NTN 4T-759/752", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 88.9, "D_mm": 161.925, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 299, "static_load_kN": 385, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 4100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.5 in (88.9 mm) shaft position as 4T-759/752: cone 759, cup 752, profiled rollers and a pressed-steel cage, rated 299 kN basic dynamic and 385 kN static. Reading the designation: 4T-759/752 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 3.4 kN of dynamic capacity per millimetre of bore summarises the 299 kN rating over the 88.9 mm bore — sanity-check any interchange candidate against this ratio and the 47.625 mm T. Housing fitment sequence for 4T-759/752: press the 752 cup square into the 161.925 mm seat first, then bring the 759 cone (on its 88.9 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 88.9 mm cone with an induction heater (max 120 °C) and press the 161.925 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 88.9 mm cone by induction heating (max 120 °C) and the 161.925 mm cup with a press sleeve; at 4100 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 88.9 mm bore (161.925×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 759/752 reference at purchase.", "Inch and metric bores collide on paper — 88.9 mm is 3.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Inch and metric bores collide on paper — 88.9 mm is 3.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Quote the full 759/752 pair at ordering: the 759 cone also ships against sibling cups, and a cup from another reference changes the 47.625 mm assembled width and the rating.", "The 299/385 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-759/752; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-759/752?", "a": "4T-759/752 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 88.9 mm bore (3.5 in), 161.925 mm outside diameter and 47.625 mm assembled width T (6.375 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 299 kN, C0 385 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 4100 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-759/752 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 759 cone or the 752 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 299/385 kN ratings change with the cup." }, { "q": "What is the difference between 4T-759/752 and a metric ISO 355 tapered bearing?", "a": "4T-759/752 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 88.9×161.925×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-759/752 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 759/752 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-759/752 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-759/752 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "759", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-759-752", "759-752", "4T-759-752" ], "locale_variants": {} }, { "sku": "850-832", "brand": "NTN", "manufacturer_designation": "NTN 4T-850/832", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 88.9, "D_mm": 168.275, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 375, "static_load_kN": 460, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 3000, "weight_g": 5090, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-850/832 is the NTN 4T catalogue entry for a 88.9×168.275×53.975 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-850/832 are separately stocked parts: a worn 832 cup can be replaced against the existing 850 cone, provided the new cup carries the identical reference — pairing across references changes the 53.975 mm assembled width and the rating. The 4.2 kN of dynamic capacity per millimetre of bore summarises the 375 kN rating over the 88.9 mm bore — sanity-check any interchange candidate against this ratio and the 53.975 mm T. Cup-side note for 832: within the pure-numeric inch family tables the 850 cone is listed against several cup options, and it is the cup that fixes the 168.275 mm OD and the 53.975 mm assembled width — quote the full 850/832 pair, never the cone alone. Mount the 88.9 mm cone with an induction heater (max 120 °C) and press the 168.275 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 88.9 mm cone by induction heating (max 120 °C) and the 168.275 mm cup with a press sleeve; at 5090 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 88.9 mm bore (168.275×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 850/832 reference at purchase.", "Inch and metric bores collide on paper — 88.9 mm is 3.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 88.9 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 88.9×168.275 mm envelope interchangeable, not the ratings: NTN prints 375/460 kN for this execution and another make of the same number can differ in roller complement.", "The 375/460 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-850/832; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-850/832?", "a": "4T-850/832 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 88.9 mm bore (3.5 in), 168.275 mm outside diameter and 53.975 mm assembled width T (6.625 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 375 kN, C0 460 kN, grease limiting speed 2,200 r/min, oil speed 3,000 r/min, mass about 5090 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-850/832 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 850 cone or the 832 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 375/460 kN ratings change with the cup." }, { "q": "What is the difference between 4T-850/832 and a metric ISO 355 tapered bearing?", "a": "4T-850/832 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 88.9×168.275×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-850/832 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 850/832 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-850/832 list two speeds, 2,200 and 3,000 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-850/832 at 3,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "850", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-850-832", "850-832", "4T-850-832" ], "locale_variants": {} }, { "sku": "HM218248-HM218210", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM218248/HM218210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 89.974, "D_mm": 146.975, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 252, "static_load_kN": 340, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM218248/HM218210 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-HM218248/HM218210 are separately stocked parts: a worn HM218210 cup can be replaced against the existing HM218248 cone, provided the new cup carries the identical reference — pairing across references changes the 40 mm assembled width and the rating. Grease relubrication at the 2,400 r/min limiting speed targets the cone-rib contact; sustaining 3,200 r/min needs an oil supply directed at the large roller ends. Cup-side note for HM218210: within the heavy-medium HM family tables the HM218248 cone is listed against several cup options, and it is the cup that fixes the 146.975 mm OD and the 40 mm assembled width — quote the full HM218248/HM218210 pair, never the cone alone. Fillet radii must clear the chamfers of the HM218248 cone and HM218210 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 89.974 mm cone by induction heating (max 120 °C) and the 146.975 mm cup with a press sleeve; at 2550 g a cocked ring brinells the raceway directly.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 89.974 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Inch and metric bores collide on paper — 89.974 mm is 3.542 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Quote the full HM218248/HM218210 pair at ordering: the HM218248 cone also ships against sibling cups, and a cup from another reference changes the 40 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of HM218248 and HM218210; use undercut shoulders so the rings seat on the face, not on a radius.", "The 252/340 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM218248/HM218210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM218248/HM218210?", "a": "4T-HM218248/HM218210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 89.974 mm bore (3.542 in), 146.975 mm outside diameter and 40 mm assembled width T (5.786 × 1.575 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 252 kN, C0 340 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 2550 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM218248/HM218210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM218248 cone or the HM218210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 252/340 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM218248/HM218210 and a metric ISO 355 tapered bearing?", "a": "4T-HM218248/HM218210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 89.974×146.975×40 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM218248/HM218210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM218248/HM218210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM218248/HM218210 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM218248/HM218210 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM218248-210", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm218248-hm218210", "hm218248-hm218210", "HM218248-HM218210", "4T-HM218248-HM218210" ], "locale_variants": {} }, { "sku": "JM718149-JM718110", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM718149/JM718110", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 145, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 210, "static_load_kN": 279, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3200, "weight_g": 2140, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JM718149/JM718110 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 90×145×35 mm (assembled width T), for a shaft of about 90 mm (3.543 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: JM718149 identifies the cone of 90 mm (3.543 in) bore by catalogue lookup, and JM718110 fixes the 145 mm OD. Catalogue mass of the 4T-JM718149/JM718110 cone-plus-cup set is 2140 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-JM718149/JM718110: press the JM718110 cup square into the 145 mm seat first, then bring the JM718149 cone (on its 90 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-JM718149/JM718110 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the 145 mm cup with a press sleeve; at 2140 g a cocked ring brinells the raceway directly.", "The J-prefixed JM718149 code belongs to a metric-envelope inch family: its 90 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Do not confuse T (35 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Shaft and housing fillets must clear the ring chamfers of JM718149 and JM718110; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 35 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,200 r/min raises temperature and destroys the setting.", "The 210/279 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM718149/JM718110; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM718149/JM718110?", "a": "4T-JM718149/JM718110 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 90 mm bore (3.543 in), 145 mm outside diameter and 35 mm assembled width T (5.709 × 1.378 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 210 kN, C0 279 kN, grease limiting speed 2,400 r/min, oil speed 3,200 r/min, mass about 2140 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM718149/JM718110 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM718149 cone or the JM718110 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 210/279 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM718149/JM718110 and a metric ISO 355 tapered bearing?", "a": "4T-JM718149/JM718110 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 90×145×35 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM718149/JM718110 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM718149/JM718110 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM718149/JM718110 list two speeds, 2,400 and 3,200 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM718149/JM718110 at 3,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM718149", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm718149-jm718110", "4t-jm718149-jm718110", "jm718149-jm718110", "JM718149-JM718110", "4T-JM718149-JM718110" ], "locale_variants": {} }, { "sku": "JHM318448-JHM318410", "brand": "NTN", "manufacturer_designation": "NTN 4T-JHM318448/JHM318410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 155, "B_mm": 44, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 299, "static_load_kN": 385, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 3330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.543 in (90 mm) shaft position as 4T-JHM318448/JHM318410: cone JHM318448, cup JHM318410, profiled rollers and a pressed-steel cage, rated 299 kN basic dynamic and 385 kN static. Reading the designation: 4T-JHM318448/JHM318410 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the JHM heavy metric-envelope family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 90×155×44 mm converts to 3.543 × 6.102 × 1.732 in; the ABMA envelope swaps with like-numbered inch parts but the 299/385 kN ratings are NTN-specific. The printed 299/385 kN ratings belong to the assembled JHM318448+JHM318410 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-JHM318448/JHM318410 run near 2,300 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the 155 mm cup with a press sleeve; at 3330 g a cocked ring brinells the raceway directly.", "The J-prefixed JHM318448 code belongs to a metric-envelope inch family: its 90 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Open 4T-JHM318448/JHM318410 sets have no seals: a hub or gearbox needs external sealing or the 2,300 r/min grease figure is meaningless once water reaches the cone rib.", "Do not confuse T (44 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 44 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 299/385 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JHM318448/JHM318410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JHM318448/JHM318410?", "a": "4T-JHM318448/JHM318410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 90 mm bore (3.543 in), 155 mm outside diameter and 44 mm assembled width T (6.102 × 1.732 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 299 kN, C0 385 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 3330 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JHM318448/JHM318410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JHM318448 cone or the JHM318410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 299/385 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JHM318448/JHM318410 and a metric ISO 355 tapered bearing?", "a": "4T-JHM318448/JHM318410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 90×155×44 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JHM318448/JHM318410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JHM318448/JHM318410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JHM318448/JHM318410 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JHM318448/JHM318410 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JHM318448", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jhm318448-jhm318410", "4t-jhm318448-jhm318410", "jhm318448-jhm318410", "JHM318448-JHM318410", "4T-JHM318448-JHM318410" ], "locale_variants": {} }, { "sku": "J90354-J90748", "brand": "NTN", "manufacturer_designation": "NTN 4T-J90354/J90748", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 90, "D_mm": 190, "B_mm": 50.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 310, "static_load_kN": 365, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 6320, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.543 in (90 mm) shaft position as 4T-J90354/J90748: cone J90354, cup J90748, profiled rollers and a pressed-steel cage, rated 310 kN basic dynamic and 365 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: J90354 identifies the cone of 90 mm (3.543 in) bore by catalogue lookup, and J90748 fixes the 190 mm OD. Selection: C 310 kN against C0 365 kN gives a C0/C ratio of 1.18 for the 90 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for J90748: within the J prefixed family tables the J90354 cone is listed against several cup options, and it is the cup that fixes the 190 mm OD and the 50.8 mm assembled width — quote the full J90354/J90748 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 90 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 90 mm cone by induction heating (max 120 °C) and the 190 mm cup with a press sleeve; at 6320 g a cocked ring brinells the raceway directly.", "The J-prefixed J90354 code belongs to a metric-envelope inch family: its 90 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Inch and metric bores collide on paper — 90 mm is 3.543 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Replacing one half of an adjusted pair without resetting end play negates the 50.8 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Quote the full J90354/J90748 pair at ordering: the J90354 cone also ships against sibling cups, and a cup from another reference changes the 50.8 mm assembled width and the rating.", "The 310/365 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-J90354/J90748; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-J90354/J90748?", "a": "4T-J90354/J90748 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 90 mm bore (3.543 in), 190 mm outside diameter and 50.8 mm assembled width T (7.48 × 2 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 310 kN, C0 365 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 6320 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-J90354/J90748 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the J90354 cone or the J90748 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 310/365 kN ratings change with the cup." }, { "q": "What is the difference between 4T-J90354/J90748 and a metric ISO 355 tapered bearing?", "a": "4T-J90354/J90748 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 90×190×50.8 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-J90354/J90748 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare J90354/J90748 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-J90354/J90748 list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-J90354/J90748 at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "J90354", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-j90354-j90748", "4t-j90354-j90748", "j90354-j90748", "J90354-J90748", "4T-J90354-J90748" ], "locale_variants": {} }, { "sku": "760-752", "brand": "NTN", "manufacturer_designation": "NTN 4T-760/752", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 90.488, "D_mm": 161.925, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 299, "static_load_kN": 385, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 4010, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-760/752 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 760/752 without it. The 35.7 mm radial section over the 90.488 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-760/752: press the 752 cup square into the 161.925 mm seat first, then bring the 760 cone (on its 90.488 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-760/752 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 90.488 mm cone by induction heating (max 120 °C) and the 161.925 mm cup with a press sleeve; at 4010 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 90.488 mm bore (161.925×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 760/752 reference at purchase.", "An unloaded 4T-760/752 near 2,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Fit selection follows the rotating ring: a rotating cone on a 90.488 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "An unloaded 4T-760/752 near 2,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 299/385 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-760/752; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-760/752?", "a": "4T-760/752 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 90.488 mm bore (3.563 in), 161.925 mm outside diameter and 47.625 mm assembled width T (6.375 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 299 kN, C0 385 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 4010 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-760/752 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 760 cone or the 752 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 299/385 kN ratings change with the cup." }, { "q": "What is the difference between 4T-760/752 and a metric ISO 355 tapered bearing?", "a": "4T-760/752 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 90.488×161.925×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-760/752 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 760/752 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-760/752 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-760/752 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "760", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-760-752", "760-752", "4T-760-752" ], "locale_variants": {} }, { "sku": "47890-47820-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-47890/47820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 92.075, "D_mm": 146.05, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 181, "static_load_kN": 266, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3100, "weight_g": 2080, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-47890/47820 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 47890 and cup 47820 delivered as a matched, separable pair of 92.075 mm bore and 146.05 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 47890/47820 without it. The 2.0 kN of dynamic capacity per millimetre of bore summarises the 181 kN rating over the 92.075 mm bore — sanity-check any interchange candidate against this ratio and the 33.338 mm T. The printed 181/266 kN ratings belong to the assembled 47890+47820 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 92.075 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 92.075 mm cone by induction heating (max 120 °C) and the 146.05 mm cup with a press sleeve; at 2080 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 92.075 mm bore (146.05×33.338 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 47890/47820 reference at purchase.", "Do not confuse T (33.338 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Do not confuse T (33.338 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Never drive the 146.05 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 181/266 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-47890/47820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-47890/47820?", "a": "4T-47890/47820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 92.075 mm bore (3.625 in), 146.05 mm outside diameter and 33.338 mm assembled width T (5.75 × 1.313 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 266 kN, grease limiting speed 2,400 r/min, oil speed 3,100 r/min, mass about 2080 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-47890/47820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 47890 cone or the 47820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 181/266 kN ratings change with the cup." }, { "q": "What is the difference between 4T-47890/47820 and a metric ISO 355 tapered bearing?", "a": "4T-47890/47820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 92.075×146.05×33.338 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-47890/47820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 47890/47820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-47890/47820 list two speeds, 2,400 and 3,100 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-47890/47820 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "47890-47820", "equiv_brand": "SKF", "level": "partial", "note": "Same 92.075×146.05×33.338 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-47890-47820", "47890-47820", "4T-47890-47820", "47890-47820-NTN" ], "locale_variants": {} }, { "sku": "598A-592A", "brand": "NTN", "manufacturer_designation": "NTN 4T-598A/592A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 92.075, "D_mm": 152.4, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 199, "static_load_kN": 279, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 2630, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.625 in (92.075 mm) shaft position as 4T-598A/592A: cone 598A, cup 592A, profiled rollers and a pressed-steel cage, rated 199 kN basic dynamic and 279 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 598A sits in the pure-numeric inch family. Selection: C 199 kN against C0 279 kN gives a C0/C ratio of 1.40 for the 92.075 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-598A/592A: press the 592A cup square into the 152.4 mm seat first, then bring the 598A cone (on its 92.075 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-598A/592A sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 92.075 mm cone by induction heating (max 120 °C) and the 152.4 mm cup with a press sleeve; at 2630 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 92.075 mm bore (152.4×39.688 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 598A/592A reference at purchase.", "Inch and metric bores collide on paper — 92.075 mm is 3.625 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Quote the full 598A/592A pair at ordering: the 598A cone also ships against sibling cups, and a cup from another reference changes the 39.688 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 92.075 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 199/279 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-598A/592A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-598A/592A?", "a": "4T-598A/592A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 92.075 mm bore (3.625 in), 152.4 mm outside diameter and 39.688 mm assembled width T (6 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 199 kN, C0 279 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 2630 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-598A/592A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 598A cone or the 592A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 199/279 kN ratings change with the cup." }, { "q": "What is the difference between 4T-598A/592A and a metric ISO 355 tapered bearing?", "a": "4T-598A/592A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 92.075×152.4×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-598A/592A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 598A/592A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-598A/592A list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-598A/592A at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "598A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-598a-592a", "598a-592a", "598A-592A", "4T-598A-592A" ], "locale_variants": {} }, { "sku": "681-672", "brand": "NTN", "manufacturer_designation": "NTN 4T-681/672", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 92.075, "D_mm": 168.275, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 247, "static_load_kN": 340, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 3870, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-681/672 is the NTN 4T catalogue entry for a 92.075×168.275×41.275 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-681/672 are separately stocked parts: a worn 672 cup can be replaced against the existing 681 cone, provided the new cup carries the identical reference — pairing across references changes the 41.275 mm assembled width and the rating. The 2.7 kN of dynamic capacity per millimetre of bore summarises the 247 kN rating over the 92.075 mm bore — sanity-check any interchange candidate against this ratio and the 41.275 mm T. The printed 247/340 kN ratings belong to the assembled 681+672 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-681/672 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 92.075 mm cone by induction heating (max 120 °C) and the 168.275 mm cup with a press sleeve; at 3870 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 92.075 mm bore (168.275×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 681/672 reference at purchase.", "Grease packs must leave free volume inside the 41.275 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,800 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 92.075 mm is 3.625 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-681/672 sets have no seals: a hub or gearbox needs external sealing or the 2,100 r/min grease figure is meaningless once water reaches the cone rib.", "The 247/340 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-681/672; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-681/672?", "a": "4T-681/672 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 92.075 mm bore (3.625 in), 168.275 mm outside diameter and 41.275 mm assembled width T (6.625 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 247 kN, C0 340 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 3870 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-681/672 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 681 cone or the 672 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 247/340 kN ratings change with the cup." }, { "q": "What is the difference between 4T-681/672 and a metric ISO 355 tapered bearing?", "a": "4T-681/672 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 92.075×168.275×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-681/672 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 681/672 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-681/672 list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-681/672 at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "681", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-681-672", "681-672", "4T-681-672" ], "locale_variants": {} }, { "sku": "42368-42584", "brand": "NTN", "manufacturer_designation": "NTN 4T-42368/42584", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 93.662, "D_mm": 148.43, "B_mm": 28.575, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 215, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 1800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-42368/42584 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-42368/42584 are separately stocked parts: a worn 42584 cup can be replaced against the existing 42368 cone, provided the new cup carries the identical reference — pairing across references changes the 28.575 mm assembled width and the rating. Catalogue mass of the 4T-42368/42584 cone-plus-cup set is 1800 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 153/215 kN ratings belong to the assembled 42368+42584 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 93.662 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 93.662 mm cone by induction heating (max 120 °C) and the 148.43 mm cup with a press sleeve; at 1800 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 93.662 mm bore (148.43×28.575 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 42368/42584 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 42368 and 42584; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-42368/42584 near 2,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Quote the full 42368/42584 pair at ordering: the 42368 cone also ships against sibling cups, and a cup from another reference changes the 28.575 mm assembled width and the rating.", "The 153/215 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-42368/42584; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-42368/42584?", "a": "4T-42368/42584 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 93.662 mm bore (3.687 in), 148.43 mm outside diameter and 28.575 mm assembled width T (5.844 × 1.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 215 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 1800 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-42368/42584 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 42368 cone or the 42584 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/215 kN ratings change with the cup." }, { "q": "What is the difference between 4T-42368/42584 and a metric ISO 355 tapered bearing?", "a": "4T-42368/42584 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 93.662×148.43×28.575 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-42368/42584 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 42368/42584 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-42368/42584 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-42368/42584 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "42368", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-42368-42584", "42368-42584", "4T-42368-42584" ], "locale_variants": {} }, { "sku": "JM719149-JM719113", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM719149/JM719113", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 95, "D_mm": 150, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 199, "static_load_kN": 279, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 2190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 95 mm carrying combined radial and thrust load, NTN lists 4T-JM719149/JM719113, a single-row 4T tapered roller set of 199 kN C and 279 kN C0 inside the 150 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — JM719149 sits in the JM metric-envelope family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 35 mm T of each 4T-JM719149/JM719113 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-JM719149/JM719113: press the JM719113 cup square into the 150 mm seat first, then bring the JM719149 cone (on its 95 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Contact-pattern check with marking blue: a pattern biased to one roller end means the 95 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 95 mm cone by induction heating (max 120 °C) and the 150 mm cup with a press sleeve; at 2190 g a cocked ring brinells the raceway directly.", "The J-prefixed JM719149 code belongs to a metric-envelope inch family: its 95 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Shaft and housing fillets must clear the ring chamfers of JM719149 and JM719113; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full JM719149/JM719113 pair at ordering: the JM719149 cone also ships against sibling cups, and a cup from another reference changes the 35 mm assembled width and the rating.", "Do not confuse T (35 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 199/279 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM719149/JM719113; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM719149/JM719113?", "a": "4T-JM719149/JM719113 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 95 mm bore (3.74 in), 150 mm outside diameter and 35 mm assembled width T (5.906 × 1.378 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 199 kN, C0 279 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 2190 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM719149/JM719113 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM719149 cone or the JM719113 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 199/279 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM719149/JM719113 and a metric ISO 355 tapered bearing?", "a": "4T-JM719149/JM719113 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 95×150×35 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM719149/JM719113 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM719149/JM719113 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM719149/JM719113 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM719149/JM719113 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM719149", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=190", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm719149-jm719113", "4t-jm719149-jm719113", "jm719149-jm719113", "JM719149-JM719113", "4T-JM719149-JM719113" ], "locale_variants": {} }, { "sku": "L319249-L319210", "brand": "NTN", "manufacturer_designation": "NTN 4T-L319249/L319210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 95.25, "D_mm": 130.175, "B_mm": 20.638, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 90, "static_load_kN": 147, "limiting_speed_rpm": 2500, "max_rpm": 2500, "speed_oil_rpm": 3300, "weight_g": 786, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-L319249/L319210 at 95.25 mm bore (3.75 in), 130.175 mm cup OD and 20.638 mm assembled T, with a grease limiting speed of 2,500 r/min and an oil ceiling of 3,300 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote L319249/L319210 without it. Grease relubrication at the 2,500 r/min limiting speed targets the cone-rib contact; sustaining 3,300 r/min needs an oil supply directed at the large roller ends. The printed 90/147 kN ratings belong to the assembled L319249+L319210 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-L319249/L319210 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 95.25 mm cone by induction heating (max 120 °C) and the 130.175 mm cup with a press sleeve; at 786 g a cocked ring brinells the raceway directly.", "The light L family at 95.25 mm bore (130.175×20.638 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L319249/L319210 reference at purchase.", "Do not confuse T (20.638 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "ABMA makes the 95.25×130.175 mm envelope interchangeable, not the ratings: NTN prints 90/147 kN for this execution and another make of the same number can differ in roller complement.", "Open 4T-L319249/L319210 sets have no seals: a hub or gearbox needs external sealing or the 2,500 r/min grease figure is meaningless once water reaches the cone rib.", "The 90/147 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L319249/L319210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L319249/L319210?", "a": "4T-L319249/L319210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 95.25 mm bore (3.75 in), 130.175 mm outside diameter and 20.638 mm assembled width T (5.125 × 0.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 90 kN, C0 147 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 786 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L319249/L319210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L319249 cone or the L319210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 90/147 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L319249/L319210 and a metric ISO 355 tapered bearing?", "a": "4T-L319249/L319210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 95.25×130.175×20.638 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L319249/L319210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L319249/L319210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L319249/L319210 list two speeds, 2,500 and 3,300 r/min?", "a": "The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L319249/L319210 at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L319249", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l319249-l319210", "l319249-l319210", "L319249-L319210", "4T-L319249-L319210" ], "locale_variants": {} }, { "sku": "47896-47820-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-47896/47820", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 95.25, "D_mm": 146.05, "B_mm": 33.338, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 181, "static_load_kN": 266, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3100, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 95.25 mm carrying combined radial and thrust load, NTN lists 4T-47896/47820, a single-row 4T tapered roller set of 181 kN C and 266 kN C0 inside the 146.05 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 47896 identifies the cone of 95.25 mm (3.75 in) bore by catalogue lookup, and 47820 fixes the 146.05 mm OD. Catalogue mass of the 4T-47896/47820 cone-plus-cup set is 1950 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-47896/47820: press the 47820 cup square into the 146.05 mm seat first, then bring the 47896 cone (on its 95.25 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 95.25 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 95.25 mm cone by induction heating (max 120 °C) and the 146.05 mm cup with a press sleeve; at 1950 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 95.25 mm bore (146.05×33.338 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 47896/47820 reference at purchase.", "Do not confuse T (33.338 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Shaft and housing fillets must clear the ring chamfers of 47896 and 47820; use undercut shoulders so the rings seat on the face, not on a radius.", "Replacing one half of an adjusted pair without resetting end play negates the 33.338 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 181/266 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-47896/47820; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-47896/47820?", "a": "4T-47896/47820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 95.25 mm bore (3.75 in), 146.05 mm outside diameter and 33.338 mm assembled width T (5.75 × 1.313 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 181 kN, C0 266 kN, grease limiting speed 2,400 r/min, oil speed 3,100 r/min, mass about 1950 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-47896/47820 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 47896 cone or the 47820 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 181/266 kN ratings change with the cup." }, { "q": "What is the difference between 4T-47896/47820 and a metric ISO 355 tapered bearing?", "a": "4T-47896/47820 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 95.25×146.05×33.338 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-47896/47820 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 47896/47820 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-47896/47820 list two speeds, 2,400 and 3,100 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-47896/47820 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "47896-47820", "equiv_brand": "SKF", "level": "partial", "note": "Same 95.25×146.05×33.338 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-47896-47820", "47896-47820", "4T-47896-47820", "47896-47820-NTN" ], "locale_variants": {} }, { "sku": "594A-592XE", "brand": "NTN", "manufacturer_designation": "NTN 4T-594A/592XE", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 95.25, "D_mm": 147.638, "B_mm": 35.717, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 199, "static_load_kN": 279, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 2090, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-594A/592XE is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 95.25×147.638×35.717 mm (assembled width T), for a shaft of about 95.25 mm (3.75 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 594A/592XE without it. Contact-angle geometry of the pure-numeric inch family gives 4T-594A/592XE its radial/axial load split — at 199/279 kN the static rating is about 1.40× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-594A/592XE: press the 592XE cup square into the 147.638 mm seat first, then bring the 594A cone (on its 95.25 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-594A/592XE run near 2,300 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 95.25 mm cone by induction heating (max 120 °C) and the 147.638 mm cup with a press sleeve; at 2090 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 95.25 mm bore (147.638×35.717 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 594A/592XE reference at purchase.", "An unloaded 4T-594A/592XE near 2,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 35.717 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 95.25 mm is 3.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 199/279 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-594A/592XE; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-594A/592XE?", "a": "4T-594A/592XE is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 95.25 mm bore (3.75 in), 147.638 mm outside diameter and 35.717 mm assembled width T (5.813 × 1.406 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 199 kN, C0 279 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 2090 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-594A/592XE interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 594A cone or the 592XE cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 199/279 kN ratings change with the cup." }, { "q": "What is the difference between 4T-594A/592XE and a metric ISO 355 tapered bearing?", "a": "4T-594A/592XE follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 95.25×147.638×35.717 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-594A/592XE mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 594A/592XE references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-594A/592XE list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-594A/592XE at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "594A-592A", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-594a-592xe", "594a-592xe", "594A-592XE", "4T-594A-592XE" ], "locale_variants": {} }, { "sku": "42375-42584", "brand": "NTN", "manufacturer_designation": "NTN 4T-42375/42584", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 95.25, "D_mm": 148.43, "B_mm": 28.575, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 215, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 1740, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-42375/42584 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 95.25×148.43×28.575 mm (assembled width T), for a shaft of about 95.25 mm (3.75 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 42375/42584 without it. Imperial cross-check for the drawing: 95.25×148.43×28.575 mm converts to 3.75 × 5.844 × 1.125 in; the ABMA envelope swaps with like-numbered inch parts but the 153/215 kN ratings are NTN-specific. The printed 153/215 kN ratings belong to the assembled 42375+42584 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-42375/42584 run near 2,300 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 95.25 mm cone by induction heating (max 120 °C) and the 148.43 mm cup with a press sleeve; at 1740 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 95.25 mm bore (148.43×28.575 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 42375/42584 reference at purchase.", "Grease packs must leave free volume inside the 28.575 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,100 r/min raises temperature and destroys the setting.", "Open 4T-42375/42584 sets have no seals: a hub or gearbox needs external sealing or the 2,300 r/min grease figure is meaningless once water reaches the cone rib.", "Open 4T-42375/42584 sets have no seals: a hub or gearbox needs external sealing or the 2,300 r/min grease figure is meaningless once water reaches the cone rib.", "The 153/215 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-42375/42584; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-42375/42584?", "a": "4T-42375/42584 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 95.25 mm bore (3.75 in), 148.43 mm outside diameter and 28.575 mm assembled width T (5.844 × 1.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 215 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 1740 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-42375/42584 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 42375 cone or the 42584 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/215 kN ratings change with the cup." }, { "q": "What is the difference between 4T-42375/42584 and a metric ISO 355 tapered bearing?", "a": "4T-42375/42584 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 95.25×148.43×28.575 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-42375/42584 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 42375/42584 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-42375/42584 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-42375/42584 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "42375", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-42375-42584", "42375-42584", "4T-42375-42584" ], "locale_variants": {} }, { "sku": "594-592A-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-594/592A", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 95.25, "D_mm": 152.4, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 199, "static_load_kN": 279, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 2510, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 95.25 mm carrying combined radial and thrust load, NTN lists 4T-594/592A, a single-row 4T tapered roller set of 199 kN C and 279 kN C0 inside the 152.4 mm OD cup. Cone and cup of 4T-594/592A are separately stocked parts: a worn 592A cup can be replaced against the existing 594 cone, provided the new cup carries the identical reference — pairing across references changes the 39.688 mm assembled width and the rating. Catalogue mass of the 4T-594/592A cone-plus-cup set is 2510 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 592A: within the pure-numeric inch family tables the 594 cone is listed against several cup options, and it is the cup that fixes the 152.4 mm OD and the 39.688 mm assembled width — quote the full 594/592A pair, never the cone alone. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-594/592A; reverse the fit logic when the cup rotates.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 95.25 mm cone by induction heating (max 120 °C) and the 152.4 mm cup with a press sleeve; at 2510 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 95.25 mm bore (152.4×39.688 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 594/592A reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 39.688 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 95.25 mm is 3.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "ABMA makes the 95.25×152.4 mm envelope interchangeable, not the ratings: NTN prints 199/279 kN for this execution and another make of the same number can differ in roller complement.", "The 199/279 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-594/592A; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-594/592A?", "a": "4T-594/592A is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 95.25 mm bore (3.75 in), 152.4 mm outside diameter and 39.688 mm assembled width T (6 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 199 kN, C0 279 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 2510 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-594/592A interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 594 cone or the 592A cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 199/279 kN ratings change with the cup." }, { "q": "What is the difference between 4T-594/592A and a metric ISO 355 tapered bearing?", "a": "4T-594/592A follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 95.25×152.4×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-594/592A mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 594/592A references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-594/592A list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-594/592A at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "594-592A", "equiv_brand": "SKF", "level": "partial", "note": "Same 95.25×152.4×39.688 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-594-592a", "594-592a", "594-592A", "4T-594-592A", "594-592A-NTN" ], "locale_variants": {} }, { "sku": "52375-52618", "brand": "NTN", "manufacturer_designation": "NTN 4T-52375/52618", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 95.25, "D_mm": 157.162, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 208, "static_load_kN": 305, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 2900, "weight_g": 2760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-52375/52618 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 95.25×157.162×36.512 mm (assembled width T), for a shaft of about 95.25 mm (3.75 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 52375 sits in the pure-numeric inch family. Grease relubrication at the 2,200 r/min limiting speed targets the cone-rib contact; sustaining 2,900 r/min needs an oil supply directed at the large roller ends. Cup-side note for 52618: within the pure-numeric inch family tables the 52375 cone is listed against several cup options, and it is the cup that fixes the 157.162 mm OD and the 36.512 mm assembled width — quote the full 52375/52618 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 95.25 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 95.25 mm cone by induction heating (max 120 °C) and the 157.162 mm cup with a press sleeve; at 2760 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 95.25 mm bore (157.162×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 52375/52618 reference at purchase.", "An unloaded 4T-52375/52618 near 2,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 36.512 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Quote the full 52375/52618 pair at ordering: the 52375 cone also ships against sibling cups, and a cup from another reference changes the 36.512 mm assembled width and the rating.", "The 208/305 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-52375/52618; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-52375/52618?", "a": "4T-52375/52618 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 95.25 mm bore (3.75 in), 157.162 mm outside diameter and 36.512 mm assembled width T (6.187 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 208 kN, C0 305 kN, grease limiting speed 2,200 r/min, oil speed 2,900 r/min, mass about 2760 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-52375/52618 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 52375 cone or the 52618 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 208/305 kN ratings change with the cup." }, { "q": "What is the difference between 4T-52375/52618 and a metric ISO 355 tapered bearing?", "a": "4T-52375/52618 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 95.25×157.162×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-52375/52618 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 52375/52618 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-52375/52618 list two speeds, 2,200 and 2,900 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-52375/52618 at 2,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "52375", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-52375-52618", "52375-52618", "4T-52375-52618" ], "locale_variants": {} }, { "sku": "683-672-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-683/672", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 95.25, "D_mm": 168.275, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 247, "static_load_kN": 340, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 3720, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-683/672 is the NTN 4T catalogue entry for a 95.25×168.275×41.275 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 683 sits in the pure-numeric inch family. Catalogue mass of the 4T-683/672 cone-plus-cup set is 3720 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 247/340 kN ratings belong to the assembled 683+672 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-683/672 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 95.25 mm cone by induction heating (max 120 °C) and the 168.275 mm cup with a press sleeve; at 3720 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 95.25 mm bore (168.275×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 683/672 reference at purchase.", "ABMA makes the 95.25×168.275 mm envelope interchangeable, not the ratings: NTN prints 247/340 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-683/672 near 2,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 247/340 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-683/672; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-683/672?", "a": "4T-683/672 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 95.25 mm bore (3.75 in), 168.275 mm outside diameter and 41.275 mm assembled width T (6.625 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 247 kN, C0 340 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 3720 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-683/672 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 683 cone or the 672 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 247/340 kN ratings change with the cup." }, { "q": "What is the difference between 4T-683/672 and a metric ISO 355 tapered bearing?", "a": "4T-683/672 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 95.25×168.275×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-683/672 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 683/672 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-683/672 list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-683/672 at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "683-672", "equiv_brand": "SKF", "level": "partial", "note": "Same 95.25×168.275×41.275 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-683-672", "683-672", "4T-683-672", "683-672-NTN" ], "locale_variants": {} }, { "sku": "42381-42584", "brand": "NTN", "manufacturer_designation": "NTN 4T-42381/42584", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 96.838, "D_mm": 148.43, "B_mm": 28.575, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 153, "static_load_kN": 215, "limiting_speed_rpm": 2300, "max_rpm": 2300, "speed_oil_rpm": 3100, "weight_g": 1690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.813 in (96.838 mm) shaft position as 4T-42381/42584: cone 42381, cup 42584, profiled rollers and a pressed-steel cage, rated 153 kN basic dynamic and 215 kN static. Reading the designation: 4T-42381/42584 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 96.838×148.43×28.575 mm converts to 3.813 × 5.844 × 1.125 in; the ABMA envelope swaps with like-numbered inch parts but the 153/215 kN ratings are NTN-specific. Cup-side note for 42584: within the pure-numeric inch family tables the 42381 cone is listed against several cup options, and it is the cup that fixes the 148.43 mm OD and the 28.575 mm assembled width — quote the full 42381/42584 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-42381/42584 run near 2,300 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 96.838 mm cone by induction heating (max 120 °C) and the 148.43 mm cup with a press sleeve; at 1690 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 96.838 mm bore (148.43×28.575 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 42381/42584 reference at purchase.", "An unloaded 4T-42381/42584 near 2,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Grease packs must leave free volume inside the 28.575 mm-wide set; over-greasing a pair churning near the oil-band speed of 3,100 r/min raises temperature and destroys the setting.", "An unloaded 4T-42381/42584 near 2,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 153/215 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-42381/42584; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-42381/42584?", "a": "4T-42381/42584 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 96.838 mm bore (3.813 in), 148.43 mm outside diameter and 28.575 mm assembled width T (5.844 × 1.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 153 kN, C0 215 kN, grease limiting speed 2,300 r/min, oil speed 3,100 r/min, mass about 1690 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-42381/42584 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 42381 cone or the 42584 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 153/215 kN ratings change with the cup." }, { "q": "What is the difference between 4T-42381/42584 and a metric ISO 355 tapered bearing?", "a": "4T-42381/42584 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 96.838×148.43×28.575 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-42381/42584 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 42381/42584 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-42381/42584 list two speeds, 2,300 and 3,100 r/min?", "a": "The lower figure, 2,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-42381/42584 at 3,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "42381", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-42381-42584", "42381-42584", "4T-42381-42584" ], "locale_variants": {} }, { "sku": "52387-52618", "brand": "NTN", "manufacturer_designation": "NTN 4T-52387/52618", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 96.838, "D_mm": 157.162, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 208, "static_load_kN": 305, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 2900, "weight_g": 2620, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-52387/52618 at 96.838 mm bore (3.813 in), 157.162 mm cup OD and 36.512 mm assembled T, with a grease limiting speed of 2,200 r/min and an oil ceiling of 2,900 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 52387 sits in the pure-numeric inch family. The 2.1 kN of dynamic capacity per millimetre of bore summarises the 208 kN rating over the 96.838 mm bore — sanity-check any interchange candidate against this ratio and the 36.512 mm T. Housing fitment sequence for 4T-52387/52618: press the 52618 cup square into the 157.162 mm seat first, then bring the 52387 cone (on its 96.838 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-52387/52618 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 96.838 mm cone by induction heating (max 120 °C) and the 157.162 mm cup with a press sleeve; at 2620 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 96.838 mm bore (157.162×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 52387/52618 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 52387 and 52618; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 36.512 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,900 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 96.838 mm is 3.813 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 208/305 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-52387/52618; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-52387/52618?", "a": "4T-52387/52618 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 96.838 mm bore (3.813 in), 157.162 mm outside diameter and 36.512 mm assembled width T (6.187 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 208 kN, C0 305 kN, grease limiting speed 2,200 r/min, oil speed 2,900 r/min, mass about 2620 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-52387/52618 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 52387 cone or the 52618 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 208/305 kN ratings change with the cup." }, { "q": "What is the difference between 4T-52387/52618 and a metric ISO 355 tapered bearing?", "a": "4T-52387/52618 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 96.838×157.162×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-52387/52618 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 52387/52618 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-52387/52618 list two speeds, 2,200 and 2,900 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-52387/52618 at 2,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "52387", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-52387-52618", "52387-52618", "4T-52387-52618" ], "locale_variants": {} }, { "sku": "90381-90744-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-90381/90744", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 96.838, "D_mm": 188.912, "B_mm": 50.8, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 310, "static_load_kN": 365, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 5460, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 96.838 mm carrying combined radial and thrust load, NTN lists 4T-90381/90744, a single-row 4T tapered roller set of 310 kN C and 365 kN C0 inside the 188.912 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 90381 sits in the pure-numeric inch family. Grease relubrication at the 1,800 r/min limiting speed targets the cone-rib contact; sustaining 2,400 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-90381/90744: press the 90744 cup square into the 188.912 mm seat first, then bring the 90381 cone (on its 96.838 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-90381/90744; reverse the fit logic when the cup rotates.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "Mount the 96.838 mm cone by induction heating (max 120 °C) and the 188.912 mm cup with a press sleeve; at 5460 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 96.838 mm bore (188.912×50.8 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 90381/90744 reference at purchase.", "Grease packs must leave free volume inside the 50.8 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,400 r/min raises temperature and destroys the setting.", "Grease packs must leave free volume inside the 50.8 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,400 r/min raises temperature and destroys the setting.", "Do not confuse T (50.8 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 310/365 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-90381/90744; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-90381/90744?", "a": "4T-90381/90744 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 96.838 mm bore (3.813 in), 188.912 mm outside diameter and 50.8 mm assembled width T (7.437 × 2 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 310 kN, C0 365 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 5460 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-90381/90744 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 90381 cone or the 90744 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 310/365 kN ratings change with the cup." }, { "q": "What is the difference between 4T-90381/90744 and a metric ISO 355 tapered bearing?", "a": "4T-90381/90744 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 96.838×188.912×50.8 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-90381/90744 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 90381/90744 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-90381/90744 list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-90381/90744 at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "90381-90744", "equiv_brand": "SKF", "level": "partial", "note": "Same 96.838×188.912×50.8 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-90381-90744", "90381-90744", "4T-90381-90744", "90381-90744-NTN" ], "locale_variants": {} }, { "sku": "HH221440-HH221410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HH221440/HH221410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 96.838, "D_mm": 190.5, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 490, "static_load_kN": 610, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2600, "weight_g": 7500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.813 in (96.838 mm) shaft position as 4T-HH221440/HH221410: cone HH221440, cup HH221410, profiled rollers and a pressed-steel cage, rated 490 kN basic dynamic and 610 kN static. Reading the designation: 4T-HH221440/HH221410 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the extra-heavy HH family lettering ties the pair to its boundary plan. Contact-angle geometry of the extra-heavy HH family gives 4T-HH221440/HH221410 its radial/axial load split — at 490/610 kN the static rating is about 1.24× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for HH221410: within the extra-heavy HH family tables the HH221440 cone is listed against several cup options, and it is the cup that fixes the 190.5 mm OD and the 57.15 mm assembled width — quote the full HH221440/HH221410 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-HH221440/HH221410 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 96.838 mm cone by induction heating (max 120 °C) and the 190.5 mm cup with a press sleeve; at 7500 g a cocked ring brinells the raceway directly.", "The extra-heavy HH family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 96.838 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "ABMA makes the 96.838×190.5 mm envelope interchangeable, not the ratings: NTN prints 490/610 kN for this execution and another make of the same number can differ in roller complement.", "Grease packs must leave free volume inside the 57.15 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,600 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 96.838 mm is 3.813 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 490/610 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HH221440/HH221410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HH221440/HH221410?", "a": "4T-HH221440/HH221410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 96.838 mm bore (3.813 in), 190.5 mm outside diameter and 57.15 mm assembled width T (7.5 × 2.25 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 490 kN, C0 610 kN, grease limiting speed 1,900 r/min, oil speed 2,600 r/min, mass about 7500 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HH221440/HH221410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HH221440 cone or the HH221410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 490/610 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HH221440/HH221410 and a metric ISO 355 tapered bearing?", "a": "4T-HH221440/HH221410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 96.838×190.5×57.15 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HH221440/HH221410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HH221440/HH221410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HH221440/HH221410 list two speeds, 1,900 and 2,600 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HH221440/HH221410 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HH221440", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hh221440-hh221410", "hh221440-hh221410", "HH221440-HH221410", "4T-HH221440-HH221410" ], "locale_variants": {} }, { "sku": "685-672", "brand": "NTN", "manufacturer_designation": "NTN 4T-685/672", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 98.425, "D_mm": 168.275, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 247, "static_load_kN": 340, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 3570, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-685/672 is the NTN 4T catalogue entry for a 98.425×168.275×41.275 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-685/672 are separately stocked parts: a worn 672 cup can be replaced against the existing 685 cone, provided the new cup carries the identical reference — pairing across references changes the 41.275 mm assembled width and the rating. Catalogue mass of the 4T-685/672 cone-plus-cup set is 3570 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 247/340 kN ratings belong to the assembled 685+672 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 98.425 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 98.425 mm cone by induction heating (max 120 °C) and the 168.275 mm cup with a press sleeve; at 3570 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 98.425 mm bore (168.275×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 685/672 reference at purchase.", "Quote the full 685/672 pair at ordering: the 685 cone also ships against sibling cups, and a cup from another reference changes the 41.275 mm assembled width and the rating.", "Quote the full 685/672 pair at ordering: the 685 cone also ships against sibling cups, and a cup from another reference changes the 41.275 mm assembled width and the rating.", "Inch and metric bores collide on paper — 98.425 mm is 3.875 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 247/340 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-685/672; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-685/672?", "a": "4T-685/672 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 98.425 mm bore (3.875 in), 168.275 mm outside diameter and 41.275 mm assembled width T (6.625 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 247 kN, C0 340 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 3570 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-685/672 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 685 cone or the 672 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 247/340 kN ratings change with the cup." }, { "q": "What is the difference between 4T-685/672 and a metric ISO 355 tapered bearing?", "a": "4T-685/672 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 98.425×168.275×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-685/672 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 685/672 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-685/672 list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-685/672 at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "685", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-685-672", "685-672", "4T-685-672" ], "locale_variants": {} }, { "sku": "HH224334-HH224310", "brand": "NTN", "manufacturer_designation": "NTN 4T-HH224334/HH224310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 99.974, "D_mm": 212.725, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 635, "static_load_kN": 810, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2300, "weight_g": 11500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HH224334/HH224310 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 99.974×212.725×66.675 mm (assembled width T), for a shaft of about 99.974 mm (3.936 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote HH224334/HH224310 without it. Speed planning uses both catalogue columns: grease 1,700 r/min is the mechanical ceiling for 4T-HH224334/HH224310, oil 2,300 r/min with circulating oil — a 600 r/min margin at this size. Cup-side note for HH224310: within the extra-heavy HH family tables the HH224334 cone is listed against several cup options, and it is the cup that fixes the 212.725 mm OD and the 66.675 mm assembled width — quote the full HH224334/HH224310 pair, never the cone alone. Fillet radii must clear the chamfers of the HH224334 cone and HH224310 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 99.974 mm cone by induction heating (max 120 °C) and the 212.725 mm cup with a press sleeve; at 11500 g a cocked ring brinells the raceway directly.", "The extra-heavy HH family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 99.974 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Do not confuse T (66.675 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "An unloaded 4T-HH224334/HH224310 near 1,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Grease packs must leave free volume inside the 66.675 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,300 r/min raises temperature and destroys the setting.", "The 635/810 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HH224334/HH224310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HH224334/HH224310?", "a": "4T-HH224334/HH224310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 99.974 mm bore (3.936 in), 212.725 mm outside diameter and 66.675 mm assembled width T (8.375 × 2.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 635 kN, C0 810 kN, grease limiting speed 1,700 r/min, oil speed 2,300 r/min, mass about 11500 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HH224334/HH224310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HH224334 cone or the HH224310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 635/810 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HH224334/HH224310 and a metric ISO 355 tapered bearing?", "a": "4T-HH224334/HH224310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 99.974×212.725×66.675 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HH224334/HH224310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HH224334/HH224310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HH224334/HH224310 list two speeds, 1,700 and 2,300 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HH224334/HH224310 at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HH224334-310", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hh224334-hh224310", "hh224334-hh224310", "HH224334-HH224310", "4T-HH224334-HH224310" ], "locale_variants": {} }, { "sku": "JM720249-JM720210", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM720249/JM720210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 100, "D_mm": 155, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 213, "static_load_kN": 310, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 2900, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 3.937 in (100 mm) shaft position as 4T-JM720249/JM720210: cone JM720249, cup JM720210, profiled rollers and a pressed-steel cage, rated 213 kN basic dynamic and 310 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote JM720249/JM720210 without it. Grease relubrication at the 2,200 r/min limiting speed targets the cone-rib contact; sustaining 2,900 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-JM720249/JM720210: press the JM720210 cup square into the 155 mm seat first, then bring the JM720249 cone (on its 100 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-JM720249/JM720210; reverse the fit logic when the cup rotates.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 100 mm cone by induction heating (max 120 °C) and the 155 mm cup with a press sleeve; at 2400 g a cocked ring brinells the raceway directly.", "The J-prefixed JM720249 code belongs to a metric-envelope inch family: its 100 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Quote the full JM720249/JM720210 pair at ordering: the JM720249 cone also ships against sibling cups, and a cup from another reference changes the 36 mm assembled width and the rating.", "Quote the full JM720249/JM720210 pair at ordering: the JM720249 cone also ships against sibling cups, and a cup from another reference changes the 36 mm assembled width and the rating.", "Never drive the 155 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 213/310 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM720249/JM720210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM720249/JM720210?", "a": "4T-JM720249/JM720210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 100 mm bore (3.937 in), 155 mm outside diameter and 36 mm assembled width T (6.102 × 1.417 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 213 kN, C0 310 kN, grease limiting speed 2,200 r/min, oil speed 2,900 r/min, mass about 2400 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM720249/JM720210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM720249 cone or the JM720210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 213/310 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM720249/JM720210 and a metric ISO 355 tapered bearing?", "a": "4T-JM720249/JM720210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 100×155×36 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM720249/JM720210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM720249/JM720210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM720249/JM720210 list two speeds, 2,200 and 2,900 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM720249/JM720210 at 2,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM720249", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm720249-jm720210", "4t-jm720249-jm720210", "jm720249-jm720210", "JM720249-JM720210", "4T-JM720249-JM720210" ], "locale_variants": {} }, { "sku": "52393-52618", "brand": "NTN", "manufacturer_designation": "NTN 4T-52393/52618", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 100.012, "D_mm": 157.162, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 208, "static_load_kN": 305, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 2900, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-52393/52618 at 100.012 mm bore (3.937 in), 157.162 mm cup OD and 36.512 mm assembled T, with a grease limiting speed of 2,200 r/min and an oil ceiling of 2,900 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 52393/52618 without it. Contact-angle geometry of the pure-numeric inch family gives 4T-52393/52618 its radial/axial load split — at 208/305 kN the static rating is about 1.47× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-52393/52618: press the 52618 cup square into the 157.162 mm seat first, then bring the 52393 cone (on its 100.012 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-52393/52618, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 100.012 mm cone by induction heating (max 120 °C) and the 157.162 mm cup with a press sleeve; at 2550 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 100.012 mm bore (157.162×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 52393/52618 reference at purchase.", "Never drive the 157.162 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Never drive the 157.162 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Inch and metric bores collide on paper — 100.012 mm is 3.937 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 208/305 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-52393/52618; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-52393/52618?", "a": "4T-52393/52618 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 100.012 mm bore (3.937 in), 157.162 mm outside diameter and 36.512 mm assembled width T (6.187 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 208 kN, C0 305 kN, grease limiting speed 2,200 r/min, oil speed 2,900 r/min, mass about 2550 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-52393/52618 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 52393 cone or the 52618 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 208/305 kN ratings change with the cup." }, { "q": "What is the difference between 4T-52393/52618 and a metric ISO 355 tapered bearing?", "a": "4T-52393/52618 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 100.012×157.162×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-52393/52618 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 52393/52618 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-52393/52618 list two speeds, 2,200 and 2,900 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-52393/52618 at 2,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "52393", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-52393-52618", "52393-52618", "4T-52393-52618" ], "locale_variants": {} }, { "sku": "52400-52618", "brand": "NTN", "manufacturer_designation": "NTN 4T-52400/52618", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 101.6, "D_mm": 157.162, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 208, "static_load_kN": 305, "limiting_speed_rpm": 2200, "max_rpm": 2200, "speed_oil_rpm": 2900, "weight_g": 2480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-52400/52618 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 52400 and cup 52618 delivered as a matched, separable pair of 101.6 mm bore and 157.162 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 52400 identifies the cone of 101.6 mm (4 in) bore by catalogue lookup, and 52618 fixes the 157.162 mm OD. Catalogue mass of the 4T-52400/52618 cone-plus-cup set is 2480 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-52400/52618: press the 52618 cup square into the 157.162 mm seat first, then bring the 52400 cone (on its 101.6 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a m6/n6 cone seat and an easy-push cup seat are typical practice for 4T-52400/52618; reverse the fit logic when the cup rotates.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 101.6 mm cone by induction heating (max 120 °C) and the 157.162 mm cup with a press sleeve; at 2480 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 101.6 mm bore (157.162×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 52400/52618 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 101.6 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Open 4T-52400/52618 sets have no seals: a hub or gearbox needs external sealing or the 2,200 r/min grease figure is meaningless once water reaches the cone rib.", "The 208/305 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-52400/52618; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-52400/52618?", "a": "4T-52400/52618 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 101.6 mm bore (4 in), 157.162 mm outside diameter and 36.512 mm assembled width T (6.187 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 208 kN, C0 305 kN, grease limiting speed 2,200 r/min, oil speed 2,900 r/min, mass about 2480 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-52400/52618 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 52400 cone or the 52618 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 208/305 kN ratings change with the cup." }, { "q": "What is the difference between 4T-52400/52618 and a metric ISO 355 tapered bearing?", "a": "4T-52400/52618 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 101.6×157.162×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-52400/52618 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 52400/52618 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-52400/52618 list two speeds, 2,200 and 2,900 r/min?", "a": "The lower figure, 2,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-52400/52618 at 2,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "52400", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-52400-52618", "52400-52618", "4T-52400-52618" ], "locale_variants": {} }, { "sku": "687-672-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-687/672", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 101.6, "D_mm": 168.275, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 247, "static_load_kN": 340, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 3400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 4 in (101.6 mm) shaft position as 4T-687/672: cone 687, cup 672, profiled rollers and a pressed-steel cage, rated 247 kN basic dynamic and 340 kN static. Reading the designation: 4T-687/672 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 2,100 r/min limiting speed targets the cone-rib contact; sustaining 2,800 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-687/672: press the 672 cup square into the 168.275 mm seat first, then bring the 687 cone (on its 101.6 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 101.6 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "Mount the 101.6 mm cone by induction heating (max 120 °C) and the 168.275 mm cup with a press sleeve; at 3400 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 101.6 mm bore (168.275×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 687/672 reference at purchase.", "Inch and metric bores collide on paper — 101.6 mm is 4 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 101.6 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of 687 and 672; use undercut shoulders so the rings seat on the face, not on a radius.", "The 247/340 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-687/672; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-687/672?", "a": "4T-687/672 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 101.6 mm bore (4 in), 168.275 mm outside diameter and 41.275 mm assembled width T (6.625 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 247 kN, C0 340 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 3400 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-687/672 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 687 cone or the 672 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 247/340 kN ratings change with the cup." }, { "q": "What is the difference between 4T-687/672 and a metric ISO 355 tapered bearing?", "a": "4T-687/672 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 101.6×168.275×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-687/672 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 687/672 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-687/672 list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-687/672 at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "687-672", "equiv_brand": "SKF", "level": "partial", "note": "Same 101.6×168.275×41.275 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-687-672", "687-672", "4T-687-672", "687-672-NTN" ], "locale_variants": {} }, { "sku": "780-772", "brand": "NTN", "manufacturer_designation": "NTN 4T-780/772", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 101.6, "D_mm": 180.975, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 315, "static_load_kN": 430, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2700, "weight_g": 5120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 101.6 mm carrying combined radial and thrust load, NTN lists 4T-780/772, a single-row 4T tapered roller set of 315 kN C and 430 kN C0 inside the 180.975 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 780 identifies the cone of 101.6 mm (4 in) bore by catalogue lookup, and 772 fixes the 180.975 mm OD. The 39.7 mm radial section over the 101.6 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 772: within the pure-numeric inch family tables the 780 cone is listed against several cup options, and it is the cup that fixes the 180.975 mm OD and the 47.625 mm assembled width — quote the full 780/772 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-780/772 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 101.6 mm cone by induction heating (max 120 °C) and the 180.975 mm cup with a press sleeve; at 5120 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 101.6 mm bore (180.975×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 780/772 reference at purchase.", "Grease packs must leave free volume inside the 47.625 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,700 r/min raises temperature and destroys the setting.", "An unloaded 4T-780/772 near 2,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of 780 and 772; use undercut shoulders so the rings seat on the face, not on a radius.", "The 315/430 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-780/772; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-780/772?", "a": "4T-780/772 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 101.6 mm bore (4 in), 180.975 mm outside diameter and 47.625 mm assembled width T (7.125 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 315 kN, C0 430 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 5120 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-780/772 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 780 cone or the 772 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 315/430 kN ratings change with the cup." }, { "q": "What is the difference between 4T-780/772 and a metric ISO 355 tapered bearing?", "a": "4T-780/772 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 101.6×180.975×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-780/772 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 780/772 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-780/772 list two speeds, 2,000 and 2,700 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-780/772 at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "780", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-780-772", "780-772", "4T-780-772" ], "locale_variants": {} }, { "sku": "861-854", "brand": "NTN", "manufacturer_designation": "NTN 4T-861/854", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 101.6, "D_mm": 190.5, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 420, "static_load_kN": 555, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2600, "weight_g": 7000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 101.6 mm carrying combined radial and thrust load, NTN lists 4T-861/854, a single-row 4T tapered roller set of 420 kN C and 555 kN C0 inside the 190.5 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 861 sits in the pure-numeric inch family. The 44.5 mm radial section over the 101.6 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for 854: within the pure-numeric inch family tables the 861 cone is listed against several cup options, and it is the cup that fixes the 190.5 mm OD and the 57.15 mm assembled width — quote the full 861/854 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-861/854 run near 2,000 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 101.6 mm cone by induction heating (max 120 °C) and the 190.5 mm cup with a press sleeve; at 7000 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 101.6 mm bore (190.5×57.15 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 861/854 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 101.6 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Inch and metric bores collide on paper — 101.6 mm is 4 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 57.15 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,600 r/min raises temperature and destroys the setting.", "The 420/555 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-861/854; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-861/854?", "a": "4T-861/854 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 101.6 mm bore (4 in), 190.5 mm outside diameter and 57.15 mm assembled width T (7.5 × 2.25 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 420 kN, C0 555 kN, grease limiting speed 2,000 r/min, oil speed 2,600 r/min, mass about 7000 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-861/854 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 861 cone or the 854 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 420/555 kN ratings change with the cup." }, { "q": "What is the difference between 4T-861/854 and a metric ISO 355 tapered bearing?", "a": "4T-861/854 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 101.6×190.5×57.15 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-861/854 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 861/854 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-861/854 list two speeds, 2,000 and 2,600 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-861/854 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "861", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-861-854", "861-854", "4T-861-854" ], "locale_variants": {} }, { "sku": "HH221449-HH221410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HH221449/HH221410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 101.6, "D_mm": 190.5, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 490, "static_load_kN": 610, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2600, "weight_g": 7070, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-HH221449/HH221410 denotes the extra-heavy HH family of NTN inch tapered roller bearings — cone HH221449 and cup HH221410 delivered as a matched, separable pair of 101.6 mm bore and 190.5 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HH221449 sits in the extra-heavy HH family. Contact-angle geometry of the extra-heavy HH family gives 4T-HH221449/HH221410 its radial/axial load split — at 490/610 kN the static rating is about 1.24× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for HH221410: within the extra-heavy HH family tables the HH221449 cone is listed against several cup options, and it is the cup that fixes the 190.5 mm OD and the 57.15 mm assembled width — quote the full HH221449/HH221410 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-HH221449/HH221410 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 101.6 mm cone by induction heating (max 120 °C) and the 190.5 mm cup with a press sleeve; at 7070 g a cocked ring brinells the raceway directly.", "The extra-heavy HH family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 101.6 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Open 4T-HH221449/HH221410 sets have no seals: a hub or gearbox needs external sealing or the 1,900 r/min grease figure is meaningless once water reaches the cone rib.", "Inch and metric bores collide on paper — 101.6 mm is 4 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Open 4T-HH221449/HH221410 sets have no seals: a hub or gearbox needs external sealing or the 1,900 r/min grease figure is meaningless once water reaches the cone rib.", "The 490/610 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HH221449/HH221410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HH221449/HH221410?", "a": "4T-HH221449/HH221410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 101.6 mm bore (4 in), 190.5 mm outside diameter and 57.15 mm assembled width T (7.5 × 2.25 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 490 kN, C0 610 kN, grease limiting speed 1,900 r/min, oil speed 2,600 r/min, mass about 7070 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HH221449/HH221410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HH221449 cone or the HH221410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 490/610 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HH221449/HH221410 and a metric ISO 355 tapered bearing?", "a": "4T-HH221449/HH221410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 101.6×190.5×57.15 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HH221449/HH221410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HH221449/HH221410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HH221449/HH221410 list two speeds, 1,900 and 2,600 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HH221449/HH221410 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HH221449-410", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hh221449-hh221410", "hh221449-hh221410", "HH221449-HH221410", "4T-HH221449-HH221410" ], "locale_variants": {} }, { "sku": "HH221449A-HH221410", "brand": "NTN", "manufacturer_designation": "NTN 4T-HH221449A/HH221410", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 101.6, "D_mm": 190.5, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 490, "static_load_kN": 610, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2600, "weight_g": 7060, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 4 in (101.6 mm) shaft position as 4T-HH221449A/HH221410: cone HH221449A, cup HH221410, profiled rollers and a pressed-steel cage, rated 490 kN basic dynamic and 610 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HH221449A identifies the cone of 101.6 mm (4 in) bore by catalogue lookup, and HH221410 fixes the 190.5 mm OD. Contact-angle geometry of the extra-heavy HH family gives 4T-HH221449A/HH221410 its radial/axial load split — at 490/610 kN the static rating is about 1.24× C, typical of inch tapered sets proportioned for combined duty. The printed 490/610 kN ratings belong to the assembled HH221449A+HH221410 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-HH221449A/HH221410 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 101.6 mm cone by induction heating (max 120 °C) and the 190.5 mm cup with a press sleeve; at 7060 g a cocked ring brinells the raceway directly.", "The extra-heavy HH family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 101.6 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Quote the full HH221449A/HH221410 pair at ordering: the HH221449A cone also ships against sibling cups, and a cup from another reference changes the 57.15 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of HH221449A and HH221410; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 57.15 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,600 r/min raises temperature and destroys the setting.", "The 490/610 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HH221449A/HH221410; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HH221449A/HH221410?", "a": "4T-HH221449A/HH221410 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 101.6 mm bore (4 in), 190.5 mm outside diameter and 57.15 mm assembled width T (7.5 × 2.25 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 490 kN, C0 610 kN, grease limiting speed 1,900 r/min, oil speed 2,600 r/min, mass about 7060 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HH221449A/HH221410 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HH221449A cone or the HH221410 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 490/610 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HH221449A/HH221410 and a metric ISO 355 tapered bearing?", "a": "4T-HH221449A/HH221410 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 101.6×190.5×57.15 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HH221449A/HH221410 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HH221449A/HH221410 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HH221449A/HH221410 list two speeds, 1,900 and 2,600 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HH221449A/HH221410 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HH221449A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hh221449a-hh221410", "hh221449a-hh221410", "HH221449A-HH221410", "4T-HH221449A-HH221410" ], "locale_variants": {} }, { "sku": "941-932", "brand": "NTN", "manufacturer_designation": "NTN 4T-941/932", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 101.6, "D_mm": 212.725, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 525, "static_load_kN": 695, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2300, "weight_g": 11200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-941/932 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 101.6×212.725×66.675 mm (assembled width T), for a shaft of about 101.6 mm (4 in). Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 941 sits in the pure-numeric inch family. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 66.675 mm T of each 4T-941/932 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. The printed 525/695 kN ratings belong to the assembled 941+932 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 101.6 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 101.6 mm cone by induction heating (max 120 °C) and the 212.725 mm cup with a press sleeve; at 11200 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 101.6 mm bore (212.725×66.675 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 941/932 reference at purchase.", "ABMA makes the 101.6×212.725 mm envelope interchangeable, not the ratings: NTN prints 525/695 kN for this execution and another make of the same number can differ in roller complement.", "Replacing one half of an adjusted pair without resetting end play negates the 66.675 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Quote the full 941/932 pair at ordering: the 941 cone also ships against sibling cups, and a cup from another reference changes the 66.675 mm assembled width and the rating.", "The 525/695 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-941/932; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-941/932?", "a": "4T-941/932 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 101.6 mm bore (4 in), 212.725 mm outside diameter and 66.675 mm assembled width T (8.375 × 2.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 525 kN, C0 695 kN, grease limiting speed 1,800 r/min, oil speed 2,300 r/min, mass about 11200 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-941/932 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 941 cone or the 932 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 525/695 kN ratings change with the cup." }, { "q": "What is the difference between 4T-941/932 and a metric ISO 355 tapered bearing?", "a": "4T-941/932 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 101.6×212.725×66.675 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-941/932 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 941/932 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-941/932 list two speeds, 1,800 and 2,300 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-941/932 at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "941", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-941-932", "941-932", "4T-941-932" ], "locale_variants": {} }, { "sku": "HH224335-HH224310", "brand": "NTN", "manufacturer_designation": "NTN 4T-HH224335/HH224310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 101.6, "D_mm": 212.725, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 635, "static_load_kN": 810, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2300, "weight_g": 11300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HH224335/HH224310 belongs to the NTN inch 4T tapered roller range (extra-heavy HH family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HH224335 identifies the cone of 101.6 mm (4 in) bore by catalogue lookup, and HH224310 fixes the 212.725 mm OD. Contact-angle geometry of the extra-heavy HH family gives 4T-HH224335/HH224310 its radial/axial load split — at 635/810 kN the static rating is about 1.28× C, typical of inch tapered sets proportioned for combined duty. The printed 635/810 kN ratings belong to the assembled HH224335+HH224310 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Mount the 101.6 mm cone with an induction heater (max 120 °C) and press the 212.725 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 101.6 mm cone by induction heating (max 120 °C) and the 212.725 mm cup with a press sleeve; at 11300 g a cocked ring brinells the raceway directly.", "The extra-heavy HH family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 101.6 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "ABMA makes the 101.6×212.725 mm envelope interchangeable, not the ratings: NTN prints 635/810 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 101.6×212.725 mm envelope interchangeable, not the ratings: NTN prints 635/810 kN for this execution and another make of the same number can differ in roller complement.", "Inch and metric bores collide on paper — 101.6 mm is 4 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 635/810 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HH224335/HH224310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HH224335/HH224310?", "a": "4T-HH224335/HH224310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 101.6 mm bore (4 in), 212.725 mm outside diameter and 66.675 mm assembled width T (8.375 × 2.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 635 kN, C0 810 kN, grease limiting speed 1,700 r/min, oil speed 2,300 r/min, mass about 11300 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HH224335/HH224310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HH224335 cone or the HH224310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 635/810 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HH224335/HH224310 and a metric ISO 355 tapered bearing?", "a": "4T-HH224335/HH224310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 101.6×212.725×66.675 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HH224335/HH224310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HH224335/HH224310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HH224335/HH224310 list two speeds, 1,700 and 2,300 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HH224335/HH224310 at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HH224335-310", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hh224335-hh224310", "hh224335-hh224310", "HH224335-HH224310", "4T-HH224335-HH224310" ], "locale_variants": {} }, { "sku": "782-772", "brand": "NTN", "manufacturer_designation": "NTN 4T-782/772", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 104.775, "D_mm": 180.975, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 315, "static_load_kN": 430, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2700, "weight_g": 4920, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 104.775 mm carrying combined radial and thrust load, NTN lists 4T-782/772, a single-row 4T tapered roller set of 315 kN C and 430 kN C0 inside the 180.975 mm OD cup. Cone and cup of 4T-782/772 are separately stocked parts: a worn 772 cup can be replaced against the existing 782 cone, provided the new cup carries the identical reference — pairing across references changes the 47.625 mm assembled width and the rating. Selection: C 315 kN against C0 430 kN gives a C0/C ratio of 1.37 for the 104.775 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 772: within the pure-numeric inch family tables the 782 cone is listed against several cup options, and it is the cup that fixes the 180.975 mm OD and the 47.625 mm assembled width — quote the full 782/772 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-782/772 run near 2,000 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 104.775 mm cone by induction heating (max 120 °C) and the 180.975 mm cup with a press sleeve; at 4920 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 104.775 mm bore (180.975×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 782/772 reference at purchase.", "An unloaded 4T-782/772 near 2,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 104.775 mm is 4.125 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 47.625 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,700 r/min raises temperature and destroys the setting.", "The 315/430 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-782/772; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-782/772?", "a": "4T-782/772 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 104.775 mm bore (4.125 in), 180.975 mm outside diameter and 47.625 mm assembled width T (7.125 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 315 kN, C0 430 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 4920 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-782/772 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 782 cone or the 772 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 315/430 kN ratings change with the cup." }, { "q": "What is the difference between 4T-782/772 and a metric ISO 355 tapered bearing?", "a": "4T-782/772 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 104.775×180.975×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-782/772 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 782/772 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-782/772 list two speeds, 2,000 and 2,700 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-782/772 at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "782", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-782-772", "782-772", "4T-782-772" ], "locale_variants": {} }, { "sku": "37425-37625-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-37425/37625", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 107.95, "D_mm": 158.75, "B_mm": 23.02, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 114, "static_load_kN": 166, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 1370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 4.25 in (107.95 mm) shaft position as 4T-37425/37625: cone 37425, cup 37625, profiled rollers and a pressed-steel cage, rated 114 kN basic dynamic and 166 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 37425 identifies the cone of 107.95 mm (4.25 in) bore by catalogue lookup, and 37625 fixes the 158.75 mm OD. Contact-angle geometry of the pure-numeric inch family gives 4T-37425/37625 its radial/axial load split — at 114/166 kN the static rating is about 1.46× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 37625: within the pure-numeric inch family tables the 37425 cone is listed against several cup options, and it is the cup that fixes the 158.75 mm OD and the 23.02 mm assembled width — quote the full 37425/37625 pair, never the cone alone. With a rotating shaft a m6/n6 cone seat and an easy-push cup seat are typical practice for 4T-37425/37625; reverse the fit logic when the cup rotates.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 107.95 mm cone by induction heating (max 120 °C) and the 158.75 mm cup with a press sleeve; at 1370 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 107.95 mm bore (158.75×23.02 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 37425/37625 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 107.95 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Open 4T-37425/37625 sets have no seals: a hub or gearbox needs external sealing or the 2,100 r/min grease figure is meaningless once water reaches the cone rib.", "Quote the full 37425/37625 pair at ordering: the 37425 cone also ships against sibling cups, and a cup from another reference changes the 23.02 mm assembled width and the rating.", "The 114/166 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-37425/37625; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-37425/37625?", "a": "4T-37425/37625 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 107.95 mm bore (4.25 in), 158.75 mm outside diameter and 23.02 mm assembled width T (6.25 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 114 kN, C0 166 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 1370 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-37425/37625 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 37425 cone or the 37625 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 114/166 kN ratings change with the cup." }, { "q": "What is the difference between 4T-37425/37625 and a metric ISO 355 tapered bearing?", "a": "4T-37425/37625 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 107.95×158.75×23.02 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-37425/37625 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 37425/37625 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-37425/37625 list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-37425/37625 at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "37425-37625", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-37425-37625", "37425-37625", "4T-37425-37625", "37425-37625-NTN" ], "locale_variants": {} }, { "sku": "LM522546-LM522510", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM522546/LM522510", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 107.95, "D_mm": 159.987, "B_mm": 34.925, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 186, "static_load_kN": 320, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 2370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-LM522546/LM522510 denotes the light-medium LM family of NTN inch tapered roller bearings — cone LM522546 and cup LM522510 delivered as a matched, separable pair of 107.95 mm bore and 159.987 mm outside diameter. Reading the designation: 4T-LM522546/LM522510 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the light-medium LM family lettering ties the pair to its boundary plan. Selection: C 186 kN against C0 320 kN gives a C0/C ratio of 1.72 for the 107.95 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 186/320 kN ratings belong to the assembled LM522546+LM522510 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-LM522546/LM522510 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 107.95 mm cone by induction heating (max 120 °C) and the 159.987 mm cup with a press sleeve; at 2370 g a cocked ring brinells the raceway directly.", "The light-medium LM family at 107.95 mm bore (159.987×34.925 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM522546/LM522510 reference at purchase.", "Inch and metric bores collide on paper — 107.95 mm is 4.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Replacing one half of an adjusted pair without resetting end play negates the 34.925 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 107.95 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 186/320 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM522546/LM522510; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM522546/LM522510?", "a": "4T-LM522546/LM522510 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 107.95 mm bore (4.25 in), 159.987 mm outside diameter and 34.925 mm assembled width T (6.299 × 1.375 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 186 kN, C0 320 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 2370 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM522546/LM522510 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM522546 cone or the LM522510 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 186/320 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM522546/LM522510 and a metric ISO 355 tapered bearing?", "a": "4T-LM522546/LM522510 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 107.95×159.987×34.925 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM522546/LM522510 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM522546/LM522510 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM522546/LM522510 list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM522546/LM522510 at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM522546", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm522546-lm522510", "lm522546-lm522510", "LM522546-LM522510", "4T-LM522546-LM522510" ], "locale_variants": {} }, { "sku": "56425-56650-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-56425/56650", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 107.95, "D_mm": 165.1, "B_mm": 36.512, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 212, "static_load_kN": 315, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2700, "weight_g": 2690, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 4.25 in (107.95 mm) shaft position as 4T-56425/56650: cone 56425, cup 56650, profiled rollers and a pressed-steel cage, rated 212 kN basic dynamic and 315 kN static. Cone and cup of 4T-56425/56650 are separately stocked parts: a worn 56650 cup can be replaced against the existing 56425 cone, provided the new cup carries the identical reference — pairing across references changes the 36.512 mm assembled width and the rating. Grease relubrication at the 2,100 r/min limiting speed targets the cone-rib contact; sustaining 2,700 r/min needs an oil supply directed at the large roller ends. Cup-side note for 56650: within the pure-numeric inch family tables the 56425 cone is listed against several cup options, and it is the cup that fixes the 165.1 mm OD and the 36.512 mm assembled width — quote the full 56425/56650 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 107.95 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 107.95 mm cone by induction heating (max 120 °C) and the 165.1 mm cup with a press sleeve; at 2690 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 107.95 mm bore (165.1×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 56425/56650 reference at purchase.", "Inch and metric bores collide on paper — 107.95 mm is 4.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Never drive the 165.1 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 212/315 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-56425/56650; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-56425/56650?", "a": "4T-56425/56650 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 107.95 mm bore (4.25 in), 165.1 mm outside diameter and 36.512 mm assembled width T (6.5 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 212 kN, C0 315 kN, grease limiting speed 2,100 r/min, oil speed 2,700 r/min, mass about 2690 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-56425/56650 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 56425 cone or the 56650 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 212/315 kN ratings change with the cup." }, { "q": "What is the difference between 4T-56425/56650 and a metric ISO 355 tapered bearing?", "a": "4T-56425/56650 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 107.95×165.1×36.512 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-56425/56650 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 56425/56650 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-56425/56650 list two speeds, 2,100 and 2,700 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-56425/56650 at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "56425-56650", "equiv_brand": "SKF", "level": "partial", "note": "Same 107.95×165.1×36.512 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-56425-56650", "56425-56650", "4T-56425-56650", "56425-56650-NTN" ], "locale_variants": {} }, { "sku": "936-932", "brand": "NTN", "manufacturer_designation": "NTN 4T-936/932", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 107.95, "D_mm": 212.725, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 525, "static_load_kN": 695, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2300, "weight_g": 10700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-936/932 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 936 and cup 932 delivered as a matched, separable pair of 107.95 mm bore and 212.725 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 936/932 without it. Contact-angle geometry of the pure-numeric inch family gives 4T-936/932 its radial/axial load split — at 525/695 kN the static rating is about 1.32× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 932: within the pure-numeric inch family tables the 936 cone is listed against several cup options, and it is the cup that fixes the 212.725 mm OD and the 66.675 mm assembled width — quote the full 936/932 pair, never the cone alone. Minimum load matters at speed: an unloaded 4T-936/932 run near 1,800 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Mount the 107.95 mm cone by induction heating (max 120 °C) and the 212.725 mm cup with a press sleeve; at 10700 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 107.95 mm bore (212.725×66.675 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 936/932 reference at purchase.", "Inch and metric bores collide on paper — 107.95 mm is 4.25 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 66.675 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,300 r/min raises temperature and destroys the setting.", "An unloaded 4T-936/932 near 1,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 525/695 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-936/932; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-936/932?", "a": "4T-936/932 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 107.95 mm bore (4.25 in), 212.725 mm outside diameter and 66.675 mm assembled width T (8.375 × 2.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 525 kN, C0 695 kN, grease limiting speed 1,800 r/min, oil speed 2,300 r/min, mass about 10700 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-936/932 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 936 cone or the 932 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 525/695 kN ratings change with the cup." }, { "q": "What is the difference between 4T-936/932 and a metric ISO 355 tapered bearing?", "a": "4T-936/932 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 107.95×212.725×66.675 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-936/932 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 936/932 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-936/932 list two speeds, 1,800 and 2,300 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-936/932 at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "936", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-936-932", "936-932", "4T-936-932" ], "locale_variants": {} }, { "sku": "37431-37625", "brand": "NTN", "manufacturer_designation": "NTN 4T-37431/37625", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 109.538, "D_mm": 158.75, "B_mm": 23.02, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 114, "static_load_kN": 166, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 1320, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-37431/37625 is the NTN 4T catalogue entry for a 109.538×158.75×23.02 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Reading the designation: 4T-37431/37625 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 2,100 r/min limiting speed targets the cone-rib contact; sustaining 2,800 r/min needs an oil supply directed at the large roller ends. The printed 114/166 kN ratings belong to the assembled 37431+37625 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-37431/37625 run near 2,100 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Mount the 109.538 mm cone by induction heating (max 120 °C) and the 158.75 mm cup with a press sleeve; at 1320 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 109.538 mm bore (158.75×23.02 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 37431/37625 reference at purchase.", "Quote the full 37431/37625 pair at ordering: the 37431 cone also ships against sibling cups, and a cup from another reference changes the 23.02 mm assembled width and the rating.", "Grease packs must leave free volume inside the 23.02 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,800 r/min raises temperature and destroys the setting.", "An unloaded 4T-37431/37625 near 2,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 114/166 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-37431/37625; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-37431/37625?", "a": "4T-37431/37625 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 109.538 mm bore (4.313 in), 158.75 mm outside diameter and 23.02 mm assembled width T (6.25 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 114 kN, C0 166 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 1320 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-37431/37625 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 37431 cone or the 37625 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 114/166 kN ratings change with the cup." }, { "q": "What is the difference between 4T-37431/37625 and a metric ISO 355 tapered bearing?", "a": "4T-37431/37625 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 109.538×158.75×23.02 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-37431/37625 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 37431/37625 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-37431/37625 list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-37431/37625 at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "37431", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=191", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-37431-37625", "37431-37625", "4T-37431-37625" ], "locale_variants": {} }, { "sku": "LM522548-LM522510", "brand": "NTN", "manufacturer_designation": "NTN 4T-LM522548/LM522510", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 109.987, "D_mm": 159.987, "B_mm": 34.925, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 186, "static_load_kN": 320, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2800, "weight_g": 2240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-LM522548/LM522510 belongs to the NTN inch 4T tapered roller range (light-medium LM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: LM522548 identifies the cone of 109.987 mm (4.33 in) bore by catalogue lookup, and LM522510 fixes the 159.987 mm OD. Catalogue mass of the 4T-LM522548/LM522510 cone-plus-cup set is 2240 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for LM522510: within the light-medium LM family tables the LM522548 cone is listed against several cup options, and it is the cup that fixes the 159.987 mm OD and the 34.925 mm assembled width — quote the full LM522548/LM522510 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 109.987 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "off-highway and forestry machine axles", "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "Mount the 109.987 mm cone by induction heating (max 120 °C) and the 159.987 mm cup with a press sleeve; at 2240 g a cocked ring brinells the raceway directly.", "The light-medium LM family at 109.987 mm bore (159.987×34.925 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM522548/LM522510 reference at purchase.", "Open 4T-LM522548/LM522510 sets have no seals: a hub or gearbox needs external sealing or the 2,100 r/min grease figure is meaningless once water reaches the cone rib.", "Never drive the 159.987 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "An unloaded 4T-LM522548/LM522510 near 2,100 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 186/320 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM522548/LM522510; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LM522548/LM522510?", "a": "4T-LM522548/LM522510 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 109.987 mm bore (4.33 in), 159.987 mm outside diameter and 34.925 mm assembled width T (6.299 × 1.375 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 186 kN, C0 320 kN, grease limiting speed 2,100 r/min, oil speed 2,800 r/min, mass about 2240 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LM522548/LM522510 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LM522548 cone or the LM522510 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 186/320 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LM522548/LM522510 and a metric ISO 355 tapered bearing?", "a": "4T-LM522548/LM522510 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 109.987×159.987×34.925 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LM522548/LM522510 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LM522548/LM522510 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LM522548/LM522510 list two speeds, 2,100 and 2,800 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LM522548/LM522510 at 2,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LM522548", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-lm522548-lm522510", "lm522548-lm522510", "LM522548-LM522510", "4T-LM522548-LM522510" ], "locale_variants": {} }, { "sku": "64433-64700", "brand": "NTN", "manufacturer_designation": "NTN 4T-64433/64700", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 109.992, "D_mm": 177.8, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 257, "static_load_kN": 375, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2600, "weight_g": 3770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-64433/64700 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 64433 sits in the pure-numeric inch family. The 2.3 kN of dynamic capacity per millimetre of bore summarises the 257 kN rating over the 109.992 mm bore — sanity-check any interchange candidate against this ratio and the 41.275 mm T. The printed 257/375 kN ratings belong to the assembled 64433+64700 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-64433/64700 run near 1,900 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "plant gearboxes on inch-dimensioned shaft lines", "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 109.992 mm cone by induction heating (max 120 °C) and the 177.8 mm cup with a press sleeve; at 3770 g a cocked ring brinells the raceway directly.", "The pure-numeric inch family at 109.992 mm bore (177.8×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 64433/64700 reference at purchase.", "Never drive the 177.8 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (41.275 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Replacing one half of an adjusted pair without resetting end play negates the 41.275 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 257/375 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-64433/64700; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-64433/64700?", "a": "4T-64433/64700 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 109.992 mm bore (4.33 in), 177.8 mm outside diameter and 41.275 mm assembled width T (7 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 257 kN, C0 375 kN, grease limiting speed 1,900 r/min, oil speed 2,600 r/min, mass about 3770 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-64433/64700 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 64433 cone or the 64700 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 257/375 kN ratings change with the cup." }, { "q": "What is the difference between 4T-64433/64700 and a metric ISO 355 tapered bearing?", "a": "4T-64433/64700 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 109.992×177.8×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-64433/64700 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 64433/64700 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-64433/64700 list two speeds, 1,900 and 2,600 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-64433/64700 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "64433", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-64433-64700", "64433-64700", "4T-64433-64700" ], "locale_variants": {} }, { "sku": "JM822049-JM822010", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM822049/JM822010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 165, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 212, "static_load_kN": 315, "limiting_speed_rpm": 2100, "max_rpm": 2100, "speed_oil_rpm": 2700, "weight_g": 2520, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JM822049/JM822010 is the NTN 4T catalogue entry for a 110×165×35 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: JM822049 identifies the cone of 110 mm (4.331 in) bore by catalogue lookup, and JM822010 fixes the 165 mm OD. The 1.9 kN of dynamic capacity per millimetre of bore summarises the 212 kN rating over the 110 mm bore — sanity-check any interchange candidate against this ratio and the 35 mm T. The printed 212/315 kN ratings belong to the assembled JM822049+JM822010 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-JM822049/JM822010 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "large conveyor head pulleys in bulk-handling plant", "paper-machine and calender roll supports", "off-highway and forestry machine axles", "marine winch and deck-machinery shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 110 mm cone by induction heating (max 120 °C) and the 165 mm cup with a press sleeve; at 2520 g a cocked ring brinells the raceway directly.", "The J-prefixed JM822049 code belongs to a metric-envelope inch family: its 110 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Quote the full JM822049/JM822010 pair at ordering: the JM822049 cone also ships against sibling cups, and a cup from another reference changes the 35 mm assembled width and the rating.", "ABMA makes the 110×165 mm envelope interchangeable, not the ratings: NTN prints 212/315 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full JM822049/JM822010 pair at ordering: the JM822049 cone also ships against sibling cups, and a cup from another reference changes the 35 mm assembled width and the rating.", "The 212/315 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM822049/JM822010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM822049/JM822010?", "a": "4T-JM822049/JM822010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 110 mm bore (4.331 in), 165 mm outside diameter and 35 mm assembled width T (6.496 × 1.378 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 212 kN, C0 315 kN, grease limiting speed 2,100 r/min, oil speed 2,700 r/min, mass about 2520 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM822049/JM822010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM822049 cone or the JM822010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 212/315 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM822049/JM822010 and a metric ISO 355 tapered bearing?", "a": "4T-JM822049/JM822010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 110×165×35 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM822049/JM822010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM822049/JM822010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM822049/JM822010 list two speeds, 2,100 and 2,700 r/min?", "a": "The lower figure, 2,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM822049/JM822010 at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM822049", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm822049-jm822010", "4t-jm822049-jm822010", "jm822049-jm822010", "JM822049-JM822010", "4T-JM822049-JM822010" ], "locale_variants": {} }, { "sku": "JHM522649-JHM522610", "brand": "NTN", "manufacturer_designation": "NTN 4T-JHM522649/JHM522610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 110, "D_mm": 180, "B_mm": 47, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 340, "static_load_kN": 480, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2600, "weight_g": 4610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JHM522649/JHM522610 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 110×180×47 mm (assembled width T), for a shaft of about 110 mm (4.331 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: JHM522649 identifies the cone of 110 mm (4.331 in) bore by catalogue lookup, and JHM522610 fixes the 180 mm OD. Imperial cross-check for the drawing: 110×180×47 mm converts to 4.331 × 7.087 × 1.85 in; the ABMA envelope swaps with like-numbered inch parts but the 340/480 kN ratings are NTN-specific. The printed 340/480 kN ratings belong to the assembled JHM522649+JHM522610 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-JHM522649/JHM522610, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "marine winch and deck-machinery shafts", "crusher and screening-plant eccentric shafts", "heavy truck and bus drive-axle differentials", "plant gearboxes on inch-dimensioned shaft lines" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "Mount the 110 mm cone by induction heating (max 120 °C) and the 180 mm cup with a press sleeve; at 4610 g a cocked ring brinells the raceway directly.", "The J-prefixed JHM522649 code belongs to a metric-envelope inch family: its 110 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Grease packs must leave free volume inside the 47 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,600 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 110 mm is 4.331 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Shaft and housing fillets must clear the ring chamfers of JHM522649 and JHM522610; use undercut shoulders so the rings seat on the face, not on a radius.", "The 340/480 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JHM522649/JHM522610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JHM522649/JHM522610?", "a": "4T-JHM522649/JHM522610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 110 mm bore (4.331 in), 180 mm outside diameter and 47 mm assembled width T (7.087 × 1.85 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 340 kN, C0 480 kN, grease limiting speed 1,900 r/min, oil speed 2,600 r/min, mass about 4610 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JHM522649/JHM522610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JHM522649 cone or the JHM522610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 340/480 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JHM522649/JHM522610 and a metric ISO 355 tapered bearing?", "a": "4T-JHM522649/JHM522610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 110×180×47 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JHM522649/JHM522610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JHM522649/JHM522610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JHM522649/JHM522610 list two speeds, 1,900 and 2,600 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JHM522649/JHM522610 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JHM522649", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jhm522649-jhm522610", "4t-jhm522649-jhm522610", "jhm522649-jhm522610", "JHM522649-JHM522610", "4T-JHM522649-JHM522610" ], "locale_variants": {} }, { "sku": "H924045-H924010", "brand": "NTN", "manufacturer_designation": "NTN 4T-H924045/H924010", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 111.125, "D_mm": 214.312, "B_mm": 55.562, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 450, "static_load_kN": 560, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 8470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 111.125 mm carrying combined radial and thrust load, NTN lists 4T-H924045/H924010, a single-row 4T tapered roller set of 450 kN C and 560 kN C0 inside the 214.312 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — H924045 sits in the heavy H family. The 4.0 kN of dynamic capacity per millimetre of bore summarises the 450 kN rating over the 111.125 mm bore — sanity-check any interchange candidate against this ratio and the 55.562 mm T. The printed 450/560 kN ratings belong to the assembled H924045+H924010 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-H924045/H924010, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 111.125 mm bore the 4T-H924045/H924010 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 450 kN C level.", "The heavy H family at 111.125 mm bore (214.312×55.562 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full H924045/H924010 reference at purchase.", "Do not confuse T (55.562 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Grease packs must leave free volume inside the 55.562 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,000 r/min raises temperature and destroys the setting.", "Grease packs must leave free volume inside the 55.562 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,000 r/min raises temperature and destroys the setting.", "The 450/560 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-H924045/H924010; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-H924045/H924010?", "a": "4T-H924045/H924010 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 111.125 mm bore (4.375 in), 214.312 mm outside diameter and 55.562 mm assembled width T (8.437 × 2.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 450 kN, C0 560 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 8470 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-H924045/H924010 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the H924045 cone or the H924010 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 450/560 kN ratings change with the cup." }, { "q": "What is the difference between 4T-H924045/H924010 and a metric ISO 355 tapered bearing?", "a": "4T-H924045/H924010 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 111.125×214.312×55.562 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-H924045/H924010 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare H924045/H924010 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-H924045/H924010 list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-H924045/H924010 at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "H924045", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-h924045-h924010", "h924045-h924010", "H924045-H924010", "4T-H924045-H924010" ], "locale_variants": {} }, { "sku": "64450-64700-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-64450/64700", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 114.3, "D_mm": 177.8, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 257, "static_load_kN": 375, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2600, "weight_g": 3520, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-64450/64700 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 64450 and cup 64700 delivered as a matched, separable pair of 114.3 mm bore and 177.8 mm outside diameter. Cone and cup of 4T-64450/64700 are separately stocked parts: a worn 64700 cup can be replaced against the existing 64450 cone, provided the new cup carries the identical reference — pairing across references changes the 41.275 mm assembled width and the rating. Contact-angle geometry of the pure-numeric inch family gives 4T-64450/64700 its radial/axial load split — at 257/375 kN the static rating is about 1.46× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-64450/64700: press the 64700 cup square into the 177.8 mm seat first, then bring the 64450 cone (on its 114.3 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-64450/64700 run near 1,900 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 114.3 mm bore the 4T-64450/64700 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 257 kN C level.", "The pure-numeric inch family at 114.3 mm bore (177.8×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 64450/64700 reference at purchase.", "Never drive the 177.8 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Shaft and housing fillets must clear the ring chamfers of 64450 and 64700; use undercut shoulders so the rings seat on the face, not on a radius.", "Fit selection follows the rotating ring: a rotating cone on a 114.3 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 257/375 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-64450/64700; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-64450/64700?", "a": "4T-64450/64700 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 114.3 mm bore (4.5 in), 177.8 mm outside diameter and 41.275 mm assembled width T (7 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 257 kN, C0 375 kN, grease limiting speed 1,900 r/min, oil speed 2,600 r/min, mass about 3520 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-64450/64700 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 64450 cone or the 64700 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 257/375 kN ratings change with the cup." }, { "q": "What is the difference between 4T-64450/64700 and a metric ISO 355 tapered bearing?", "a": "4T-64450/64700 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 114.3×177.8×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-64450/64700 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 64450/64700 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-64450/64700 list two speeds, 1,900 and 2,600 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-64450/64700 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "64450-64700", "equiv_brand": "SKF", "level": "partial", "note": "Same 114.3×177.8×41.275 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-64450-64700", "64450-64700", "4T-64450-64700", "64450-64700-NTN" ], "locale_variants": {} }, { "sku": "68450-68712-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-68450/68712", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 114.3, "D_mm": 180.975, "B_mm": 34.925, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 187, "static_load_kN": 245, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2500, "weight_g": 2930, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-68450/68712 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 68450 identifies the cone of 114.3 mm (4.5 in) bore by catalogue lookup, and 68712 fixes the 180.975 mm OD. Grease relubrication at the 1,900 r/min limiting speed targets the cone-rib contact; sustaining 2,500 r/min needs an oil supply directed at the large roller ends. Cup-side note for 68712: within the pure-numeric inch family tables the 68450 cone is listed against several cup options, and it is the cup that fixes the 180.975 mm OD and the 34.925 mm assembled width — quote the full 68450/68712 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 114.3 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 114.3 mm bore the 4T-68450/68712 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 187 kN C level.", "The pure-numeric inch family at 114.3 mm bore (180.975×34.925 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 68450/68712 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 68450 and 68712; use undercut shoulders so the rings seat on the face, not on a radius.", "Fit selection follows the rotating ring: a rotating cone on a 114.3 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of 68450 and 68712; use undercut shoulders so the rings seat on the face, not on a radius.", "The 187/245 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-68450/68712; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-68450/68712?", "a": "4T-68450/68712 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 114.3 mm bore (4.5 in), 180.975 mm outside diameter and 34.925 mm assembled width T (7.125 × 1.375 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 187 kN, C0 245 kN, grease limiting speed 1,900 r/min, oil speed 2,500 r/min, mass about 2930 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-68450/68712 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 68450 cone or the 68712 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 187/245 kN ratings change with the cup." }, { "q": "What is the difference between 4T-68450/68712 and a metric ISO 355 tapered bearing?", "a": "4T-68450/68712 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 114.3×180.975×34.925 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-68450/68712 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 68450/68712 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-68450/68712 list two speeds, 1,900 and 2,500 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-68450/68712 at 2,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "68450-68712", "equiv_brand": "SKF", "level": "partial", "note": "Same 114.3×180.975×34.925 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-68450-68712", "68450-68712", "4T-68450-68712", "68450-68712-NTN" ], "locale_variants": {} }, { "sku": "938-932-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-938/932", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 114.3, "D_mm": 212.725, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 525, "static_load_kN": 695, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2300, "weight_g": 10100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 4.5 in (114.3 mm) shaft position as 4T-938/932: cone 938, cup 932, profiled rollers and a pressed-steel cage, rated 525 kN basic dynamic and 695 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 938 sits in the pure-numeric inch family. Grease relubrication at the 1,800 r/min limiting speed targets the cone-rib contact; sustaining 2,300 r/min needs an oil supply directed at the large roller ends. Cup-side note for 932: within the pure-numeric inch family tables the 938 cone is listed against several cup options, and it is the cup that fixes the 212.725 mm OD and the 66.675 mm assembled width — quote the full 938/932 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-938/932 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "At 114.3 mm bore the 4T-938/932 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 525 kN C level.", "The pure-numeric inch family at 114.3 mm bore (212.725×66.675 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 938/932 reference at purchase.", "An unloaded 4T-938/932 near 1,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of 938 and 932; use undercut shoulders so the rings seat on the face, not on a radius.", "Do not confuse T (66.675 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 525/695 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-938/932; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-938/932?", "a": "4T-938/932 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 114.3 mm bore (4.5 in), 212.725 mm outside diameter and 66.675 mm assembled width T (8.375 × 2.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 525 kN, C0 695 kN, grease limiting speed 1,800 r/min, oil speed 2,300 r/min, mass about 10100 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-938/932 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 938 cone or the 932 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 525/695 kN ratings change with the cup." }, { "q": "What is the difference between 4T-938/932 and a metric ISO 355 tapered bearing?", "a": "4T-938/932 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 114.3×212.725×66.675 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-938/932 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 938/932 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-938/932 list two speeds, 1,800 and 2,300 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-938/932 at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "938-932", "equiv_brand": "SKF", "level": "partial", "note": "Same 114.3×212.725×66.675 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-938-932", "938-932", "4T-938-932", "938-932-NTN" ], "locale_variants": {} }, { "sku": "HH224346-HH224310", "brand": "NTN", "manufacturer_designation": "NTN 4T-HH224346/HH224310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 114.3, "D_mm": 212.725, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 635, "static_load_kN": 810, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2300, "weight_g": 10100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 114.3 mm carrying combined radial and thrust load, NTN lists 4T-HH224346/HH224310, a single-row 4T tapered roller set of 635 kN C and 810 kN C0 inside the 212.725 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HH224346 identifies the cone of 114.3 mm (4.5 in) bore by catalogue lookup, and HH224310 fixes the 212.725 mm OD. Imperial cross-check for the drawing: 114.3×212.725×66.675 mm converts to 4.5 × 8.375 × 2.625 in; the ABMA envelope swaps with like-numbered inch parts but the 635/810 kN ratings are NTN-specific. The printed 635/810 kN ratings belong to the assembled HH224346+HH224310 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-HH224346/HH224310, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 114.3 mm bore the 4T-HH224346/HH224310 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 635 kN C level.", "The extra-heavy HH family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 114.3 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "ABMA makes the 114.3×212.725 mm envelope interchangeable, not the ratings: NTN prints 635/810 kN for this execution and another make of the same number can differ in roller complement.", "An unloaded 4T-HH224346/HH224310 near 1,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "ABMA makes the 114.3×212.725 mm envelope interchangeable, not the ratings: NTN prints 635/810 kN for this execution and another make of the same number can differ in roller complement.", "The 635/810 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HH224346/HH224310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HH224346/HH224310?", "a": "4T-HH224346/HH224310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 114.3 mm bore (4.5 in), 212.725 mm outside diameter and 66.675 mm assembled width T (8.375 × 2.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 635 kN, C0 810 kN, grease limiting speed 1,700 r/min, oil speed 2,300 r/min, mass about 10100 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HH224346/HH224310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HH224346 cone or the HH224310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 635/810 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HH224346/HH224310 and a metric ISO 355 tapered bearing?", "a": "4T-HH224346/HH224310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 114.3×212.725×66.675 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HH224346/HH224310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HH224346/HH224310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HH224346/HH224310 list two speeds, 1,700 and 2,300 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HH224346/HH224310 at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HH224346-310", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hh224346-hh224310", "hh224346-hh224310", "HH224346-HH224310", "4T-HH224346-HH224310" ], "locale_variants": {} }, { "sku": "HM926740-HM926710", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM926740/HM926710", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 114.3, "D_mm": 228.6, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 475, "static_load_kN": 620, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1900, "weight_g": 9760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM926740/HM926710 is the NTN 4T catalogue entry for a 114.3×228.6×53.975 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HM926740 identifies the cone of 114.3 mm (4.5 in) bore by catalogue lookup, and HM926710 fixes the 228.6 mm OD. Contact-angle geometry of the heavy-medium HM family gives 4T-HM926740/HM926710 its radial/axial load split — at 475/620 kN the static rating is about 1.31× C, typical of inch tapered sets proportioned for combined duty. Housing fitment sequence for 4T-HM926740/HM926710: press the HM926710 cup square into the 228.6 mm seat first, then bring the HM926740 cone (on its 114.3 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-HM926740/HM926710 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 114.3 mm bore the 4T-HM926740/HM926710 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 475 kN C level.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 114.3 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Open 4T-HM926740/HM926710 sets have no seals: a hub or gearbox needs external sealing or the 1,400 r/min grease figure is meaningless once water reaches the cone rib.", "Shaft and housing fillets must clear the ring chamfers of HM926740 and HM926710; use undercut shoulders so the rings seat on the face, not on a radius.", "Grease packs must leave free volume inside the 53.975 mm-wide set; over-greasing a pair churning near the oil-band speed of 1,900 r/min raises temperature and destroys the setting.", "The 475/620 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM926740/HM926710; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM926740/HM926710?", "a": "4T-HM926740/HM926710 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 114.3 mm bore (4.5 in), 228.6 mm outside diameter and 53.975 mm assembled width T (9 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 475 kN, C0 620 kN, grease limiting speed 1,400 r/min, oil speed 1,900 r/min, mass about 9760 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM926740/HM926710 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM926740 cone or the HM926710 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 475/620 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM926740/HM926710 and a metric ISO 355 tapered bearing?", "a": "4T-HM926740/HM926710 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 114.3×228.6×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM926740/HM926710 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM926740/HM926710 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM926740/HM926710 list two speeds, 1,400 and 1,900 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM926740/HM926710 at 1,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM926740", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm926740-hm926710", "hm926740-hm926710", "HM926740-HM926710", "4T-HM926740-HM926710" ], "locale_variants": {} }, { "sku": "71453-71750", "brand": "NTN", "manufacturer_designation": "NTN 4T-71453/71750", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 115.087, "D_mm": 190.5, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 335, "static_load_kN": 475, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2500, "weight_g": 5110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 4.531 in (115.087 mm) shaft position as 4T-71453/71750: cone 71453, cup 71750, profiled rollers and a pressed-steel cage, rated 335 kN basic dynamic and 475 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 71453/71750 without it. Selection: C 335 kN against C0 475 kN gives a C0/C ratio of 1.42 for the 115.087 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-71453/71750: press the 71750 cup square into the 190.5 mm seat first, then bring the 71453 cone (on its 115.087 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-71453/71750 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 115.087 mm bore the 4T-71453/71750 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 335 kN C level.", "The pure-numeric inch family at 115.087 mm bore (190.5×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 71453/71750 reference at purchase.", "Open 4T-71453/71750 sets have no seals: a hub or gearbox needs external sealing or the 1,800 r/min grease figure is meaningless once water reaches the cone rib.", "Never drive the 190.5 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Shaft and housing fillets must clear the ring chamfers of 71453 and 71750; use undercut shoulders so the rings seat on the face, not on a radius.", "The 335/475 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-71453/71750; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-71453/71750?", "a": "4T-71453/71750 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 115.087 mm bore (4.531 in), 190.5 mm outside diameter and 47.625 mm assembled width T (7.5 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 335 kN, C0 475 kN, grease limiting speed 1,800 r/min, oil speed 2,500 r/min, mass about 5110 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-71453/71750 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 71453 cone or the 71750 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 335/475 kN ratings change with the cup." }, { "q": "What is the difference between 4T-71453/71750 and a metric ISO 355 tapered bearing?", "a": "4T-71453/71750 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 115.087×190.5×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-71453/71750 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 71453/71750 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-71453/71750 list two speeds, 1,800 and 2,500 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-71453/71750 at 2,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "71453", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-71453-71750", "71453-71750", "4T-71453-71750" ], "locale_variants": {} }, { "sku": "68462-68712", "brand": "NTN", "manufacturer_designation": "NTN 4T-68462/68712", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 117.475, "D_mm": 180.975, "B_mm": 34.925, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 187, "static_load_kN": 245, "limiting_speed_rpm": 1900, "max_rpm": 1900, "speed_oil_rpm": 2500, "weight_g": 2780, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 4.625 in (117.475 mm) shaft position as 4T-68462/68712: cone 68462, cup 68712, profiled rollers and a pressed-steel cage, rated 187 kN basic dynamic and 245 kN static. Cone and cup of 4T-68462/68712 are separately stocked parts: a worn 68712 cup can be replaced against the existing 68462 cone, provided the new cup carries the identical reference — pairing across references changes the 34.925 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 1,900 r/min is the mechanical ceiling for 4T-68462/68712, oil 2,500 r/min with circulating oil — a 600 r/min margin at this size. Housing fitment sequence for 4T-68462/68712: press the 68712 cup square into the 180.975 mm seat first, then bring the 68462 cone (on its 117.475 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-68462/68712 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 117.475 mm bore the 4T-68462/68712 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 187 kN C level.", "The pure-numeric inch family at 117.475 mm bore (180.975×34.925 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 68462/68712 reference at purchase.", "Never drive the 180.975 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "An unloaded 4T-68462/68712 near 1,900 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Shaft and housing fillets must clear the ring chamfers of 68462 and 68712; use undercut shoulders so the rings seat on the face, not on a radius.", "The 187/245 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-68462/68712; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-68462/68712?", "a": "4T-68462/68712 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 117.475 mm bore (4.625 in), 180.975 mm outside diameter and 34.925 mm assembled width T (7.125 × 1.375 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 187 kN, C0 245 kN, grease limiting speed 1,900 r/min, oil speed 2,500 r/min, mass about 2780 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-68462/68712 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 68462 cone or the 68712 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 187/245 kN ratings change with the cup." }, { "q": "What is the difference between 4T-68462/68712 and a metric ISO 355 tapered bearing?", "a": "4T-68462/68712 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 117.475×180.975×34.925 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-68462/68712 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 68462/68712 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-68462/68712 list two speeds, 1,900 and 2,500 r/min?", "a": "The lower figure, 1,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-68462/68712 at 2,500 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "68462", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-68462-68712", "68462-68712", "4T-68462-68712" ], "locale_variants": {} }, { "sku": "JL724348-JL724314", "brand": "NTN", "manufacturer_designation": "NTN 4T-JL724348/JL724314", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 120, "D_mm": 170, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 141, "static_load_kN": 210, "limiting_speed_rpm": 2000, "max_rpm": 2000, "speed_oil_rpm": 2600, "weight_g": 1670, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-JL724348/JL724314 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 120×170×25.4 mm (assembled width T), for a shaft of about 120 mm (4.724 in). Reading the designation: 4T-JL724348/JL724314 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the JL prefixed family lettering ties the pair to its boundary plan. The 25.0 mm radial section over the 120 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 141/210 kN ratings belong to the assembled JL724348+JL724314 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-JL724348/JL724314 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 120 mm bore the 4T-JL724348/JL724314 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 141 kN C level.", "The J-prefixed JL724348 code belongs to a metric-envelope inch family: its 120 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "An unloaded 4T-JL724348/JL724314 near 2,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "ABMA makes the 120×170 mm envelope interchangeable, not the ratings: NTN prints 141/210 kN for this execution and another make of the same number can differ in roller complement.", "Open 4T-JL724348/JL724314 sets have no seals: a hub or gearbox needs external sealing or the 2,000 r/min grease figure is meaningless once water reaches the cone rib.", "The 141/210 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JL724348/JL724314; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JL724348/JL724314?", "a": "4T-JL724348/JL724314 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 120 mm bore (4.724 in), 170 mm outside diameter and 25.4 mm assembled width T (6.693 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 141 kN, C0 210 kN, grease limiting speed 2,000 r/min, oil speed 2,600 r/min, mass about 1670 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JL724348/JL724314 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JL724348 cone or the JL724314 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 141/210 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JL724348/JL724314 and a metric ISO 355 tapered bearing?", "a": "4T-JL724348/JL724314 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 120×170×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JL724348/JL724314 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JL724348/JL724314 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JL724348/JL724314 list two speeds, 2,000 and 2,600 r/min?", "a": "The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JL724348/JL724314 at 2,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JL724348", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jl724348-jl724314", "4t-jl724348-jl724314", "jl724348-jl724314", "JL724348-JL724314", "4T-JL724348-JL724314" ], "locale_variants": {} }, { "sku": "95475-95925", "brand": "NTN", "manufacturer_designation": "NTN 4T-95475/95925", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 120.65, "D_mm": 234.95, "B_mm": 63.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 580, "static_load_kN": 825, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 12600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-95475/95925 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 95475 and cup 95925 delivered as a matched, separable pair of 120.65 mm bore and 234.95 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 95475/95925 without it. The 57.1 mm radial section over the 120.65 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 580/825 kN ratings belong to the assembled 95475+95925 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Fillet radii must clear the chamfers of the 95475 cone and 95925 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 120.65 mm bore the 4T-95475/95925 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 580 kN C level.", "The pure-numeric inch family at 120.65 mm bore (234.95×63.5 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 95475/95925 reference at purchase.", "Quote the full 95475/95925 pair at ordering: the 95475 cone also ships against sibling cups, and a cup from another reference changes the 63.5 mm assembled width and the rating.", "Quote the full 95475/95925 pair at ordering: the 95475 cone also ships against sibling cups, and a cup from another reference changes the 63.5 mm assembled width and the rating.", "Shaft and housing fillets must clear the ring chamfers of 95475 and 95925; use undercut shoulders so the rings seat on the face, not on a radius.", "The 580/825 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-95475/95925; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-95475/95925?", "a": "4T-95475/95925 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 120.65 mm bore (4.75 in), 234.95 mm outside diameter and 63.5 mm assembled width T (9.25 × 2.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 580 kN, C0 825 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 12600 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-95475/95925 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 95475 cone or the 95925 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 580/825 kN ratings change with the cup." }, { "q": "What is the difference between 4T-95475/95925 and a metric ISO 355 tapered bearing?", "a": "4T-95475/95925 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 120.65×234.95×63.5 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-95475/95925 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 95475/95925 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-95475/95925 list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-95475/95925 at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "95475", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-95475-95925", "95475-95925", "4T-95475-95925" ], "locale_variants": {} }, { "sku": "48286-48220", "brand": "NTN", "manufacturer_designation": "NTN 4T-48286/48220", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 123.825, "D_mm": 182.562, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 249, "static_load_kN": 435, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 3520, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-48286/48220 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 123.825×182.562×39.688 mm (assembled width T), for a shaft of about 123.825 mm (4.875 in). Reading the designation: 4T-48286/48220 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 1,800 r/min limiting speed targets the cone-rib contact; sustaining 2,400 r/min needs an oil supply directed at the large roller ends. Cup-side note for 48220: within the pure-numeric inch family tables the 48286 cone is listed against several cup options, and it is the cup that fixes the 182.562 mm OD and the 39.688 mm assembled width — quote the full 48286/48220 pair, never the cone alone. With a rotating shaft a m6/n6 cone seat and an easy-push cup seat are typical practice for 4T-48286/48220; reverse the fit logic when the cup rotates.", "applications": [ "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 123.825 mm bore the 4T-48286/48220 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 249 kN C level.", "The pure-numeric inch family at 123.825 mm bore (182.562×39.688 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 48286/48220 reference at purchase.", "Never drive the 182.562 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "An unloaded 4T-48286/48220 near 1,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 123.825 mm is 4.875 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 249/435 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-48286/48220; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-48286/48220?", "a": "4T-48286/48220 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 123.825 mm bore (4.875 in), 182.562 mm outside diameter and 39.688 mm assembled width T (7.187 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 249 kN, C0 435 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 3520 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-48286/48220 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 48286 cone or the 48220 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 249/435 kN ratings change with the cup." }, { "q": "What is the difference between 4T-48286/48220 and a metric ISO 355 tapered bearing?", "a": "4T-48286/48220 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 123.825×182.562×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-48286/48220 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 48286/48220 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-48286/48220 list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-48286/48220 at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "48286", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-48286-48220", "48286-48220", "4T-48286-48220" ], "locale_variants": {} }, { "sku": "48290-48220-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-48290/48220", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 127, "D_mm": 182.562, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 249, "static_load_kN": 435, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 3330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-48290/48220 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 48290 and cup 48220 delivered as a matched, separable pair of 127 mm bore and 182.562 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 48290 sits in the pure-numeric inch family. Catalogue mass of the 4T-48290/48220 cone-plus-cup set is 3330 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 249/435 kN ratings belong to the assembled 48290+48220 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-48290/48220 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 127 mm bore the 4T-48290/48220 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 249 kN C level.", "The pure-numeric inch family at 127 mm bore (182.562×39.688 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 48290/48220 reference at purchase.", "Quote the full 48290/48220 pair at ordering: the 48290 cone also ships against sibling cups, and a cup from another reference changes the 39.688 mm assembled width and the rating.", "Fit selection follows the rotating ring: a rotating cone on a 127 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "An unloaded 4T-48290/48220 near 1,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 249/435 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-48290/48220; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-48290/48220?", "a": "4T-48290/48220 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 127 mm bore (5 in), 182.562 mm outside diameter and 39.688 mm assembled width T (7.187 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 249 kN, C0 435 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 3330 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-48290/48220 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 48290 cone or the 48220 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 249/435 kN ratings change with the cup." }, { "q": "What is the difference between 4T-48290/48220 and a metric ISO 355 tapered bearing?", "a": "4T-48290/48220 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 127×182.562×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-48290/48220 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 48290/48220 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-48290/48220 list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-48290/48220 at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "48290-48220", "equiv_brand": "SKF", "level": "partial", "note": "Same 127×182.562×39.688 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-48290-48220", "48290-48220", "4T-48290-48220", "48290-48220-NTN" ], "locale_variants": {} }, { "sku": "67388-67322-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-67388/67322", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 127, "D_mm": 196.85, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 340, "static_load_kN": 550, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 5100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-67388/67322 at 127 mm bore (5 in), 196.85 mm cup OD and 46.038 mm assembled T, with a grease limiting speed of 1,700 r/min and an oil ceiling of 2,200 r/min. Reading the designation: 4T-67388/67322 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 1,700 r/min limiting speed targets the cone-rib contact; sustaining 2,200 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-67388/67322: press the 67322 cup square into the 196.85 mm seat first, then bring the 67388 cone (on its 127 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. A single-row tapered bearing reacts thrust in one direction only; 4T-67388/67322 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 127 mm bore the 4T-67388/67322 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 340 kN C level.", "The pure-numeric inch family at 127 mm bore (196.85×46.038 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 67388/67322 reference at purchase.", "ABMA makes the 127×196.85 mm envelope interchangeable, not the ratings: NTN prints 340/550 kN for this execution and another make of the same number can differ in roller complement.", "Grease packs must leave free volume inside the 46.038 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,200 r/min raises temperature and destroys the setting.", "Never drive the 196.85 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 340/550 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-67388/67322; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-67388/67322?", "a": "4T-67388/67322 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 127 mm bore (5 in), 196.85 mm outside diameter and 46.038 mm assembled width T (7.75 × 1.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 340 kN, C0 550 kN, grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 5100 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-67388/67322 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 67388 cone or the 67322 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 340/550 kN ratings change with the cup." }, { "q": "What is the difference between 4T-67388/67322 and a metric ISO 355 tapered bearing?", "a": "4T-67388/67322 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 127×196.85×46.038 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-67388/67322 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 67388/67322 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-67388/67322 list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-67388/67322 at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "67388-67322", "equiv_brand": "SKF", "level": "partial", "note": "Same 127×196.85×46.038 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-67388-67322", "67388-67322", "4T-67388-67322", "67388-67322-NTN" ], "locale_variants": {} }, { "sku": "74500-74850", "brand": "NTN", "manufacturer_designation": "NTN 4T-74500/74850", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 127, "D_mm": 215.9, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 355, "static_load_kN": 540, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2100, "weight_g": 7040, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 127 mm carrying combined radial and thrust load, NTN lists 4T-74500/74850, a single-row 4T tapered roller set of 355 kN C and 540 kN C0 inside the 215.9 mm OD cup. Cone and cup of 4T-74500/74850 are separately stocked parts: a worn 74850 cup can be replaced against the existing 74500 cone, provided the new cup carries the identical reference — pairing across references changes the 47.625 mm assembled width and the rating. Catalogue mass of the 4T-74500/74850 cone-plus-cup set is 7040 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Cup-side note for 74850: within the pure-numeric inch family tables the 74500 cone is listed against several cup options, and it is the cup that fixes the 215.9 mm OD and the 47.625 mm assembled width — quote the full 74500/74850 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 127 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 127 mm bore the 4T-74500/74850 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 355 kN C level.", "The pure-numeric inch family at 127 mm bore (215.9×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 74500/74850 reference at purchase.", "Never drive the 215.9 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Inch and metric bores collide on paper — 127 mm is 5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Do not confuse T (47.625 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 355/540 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-74500/74850; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-74500/74850?", "a": "4T-74500/74850 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 127 mm bore (5 in), 215.9 mm outside diameter and 47.625 mm assembled width T (8.5 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 355 kN, C0 540 kN, grease limiting speed 1,600 r/min, oil speed 2,100 r/min, mass about 7040 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-74500/74850 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 74500 cone or the 74850 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 355/540 kN ratings change with the cup." }, { "q": "What is the difference between 4T-74500/74850 and a metric ISO 355 tapered bearing?", "a": "4T-74500/74850 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 127×215.9×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-74500/74850 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 74500/74850 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-74500/74850 list two speeds, 1,600 and 2,100 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-74500/74850 at 2,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "74500", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-74500-74850", "74500-74850", "4T-74500-74850" ], "locale_variants": {} }, { "sku": "97500-97900", "brand": "NTN", "manufacturer_designation": "NTN 4T-97500/97900", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 127, "D_mm": 228.6, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 355, "static_load_kN": 445, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1900, "weight_g": 8430, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-97500/97900 at 127 mm bore (5 in), 228.6 mm cup OD and 53.975 mm assembled T, with a grease limiting speed of 1,400 r/min and an oil ceiling of 1,900 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 97500 sits in the pure-numeric inch family. Contact-angle geometry of the pure-numeric inch family gives 4T-97500/97900 its radial/axial load split — at 355/445 kN the static rating is about 1.25× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for 97900: within the pure-numeric inch family tables the 97500 cone is listed against several cup options, and it is the cup that fixes the 228.6 mm OD and the 53.975 mm assembled width — quote the full 97500/97900 pair, never the cone alone. Fillet radii must clear the chamfers of the 97500 cone and 97900 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 127 mm bore the 4T-97500/97900 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 355 kN C level.", "The pure-numeric inch family at 127 mm bore (228.6×53.975 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 97500/97900 reference at purchase.", "Open 4T-97500/97900 sets have no seals: a hub or gearbox needs external sealing or the 1,400 r/min grease figure is meaningless once water reaches the cone rib.", "Shaft and housing fillets must clear the ring chamfers of 97500 and 97900; use undercut shoulders so the rings seat on the face, not on a radius.", "Open 4T-97500/97900 sets have no seals: a hub or gearbox needs external sealing or the 1,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 355/445 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-97500/97900; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-97500/97900?", "a": "4T-97500/97900 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 127 mm bore (5 in), 228.6 mm outside diameter and 53.975 mm assembled width T (9 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 355 kN, C0 445 kN, grease limiting speed 1,400 r/min, oil speed 1,900 r/min, mass about 8430 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-97500/97900 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 97500 cone or the 97900 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 355/445 kN ratings change with the cup." }, { "q": "What is the difference between 4T-97500/97900 and a metric ISO 355 tapered bearing?", "a": "4T-97500/97900 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 127×228.6×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-97500/97900 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 97500/97900 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-97500/97900 list two speeds, 1,400 and 1,900 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-97500/97900 at 1,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "97500", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-97500-97900", "97500-97900", "4T-97500-97900" ], "locale_variants": {} }, { "sku": "HM926747-HM926710", "brand": "NTN", "manufacturer_designation": "NTN 4T-HM926747/HM926710", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 127, "D_mm": 228.6, "B_mm": 53.975, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 475, "static_load_kN": 620, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1900, "weight_g": 8830, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HM926747/HM926710 belongs to the NTN inch 4T tapered roller range (heavy-medium HM family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — HM926747 sits in the heavy-medium HM family. Catalogue mass of the 4T-HM926747/HM926710 cone-plus-cup set is 8830 g; shaft and housing shoulders must carry that mass square to the axis during fitting. The printed 475/620 kN ratings belong to the assembled HM926747+HM926710 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. With a rotating shaft a m6/n6 cone seat and an easy-push cup seat are typical practice for 4T-HM926747/HM926710; reverse the fit logic when the cup rotates.", "applications": [ "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 127 mm bore the 4T-HM926747/HM926710 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 475 kN C level.", "The heavy-medium HM family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 127 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Fit selection follows the rotating ring: a rotating cone on a 127 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "An unloaded 4T-HM926747/HM926710 near 1,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Inch and metric bores collide on paper — 127 mm is 5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 475/620 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HM926747/HM926710; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HM926747/HM926710?", "a": "4T-HM926747/HM926710 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 127 mm bore (5 in), 228.6 mm outside diameter and 53.975 mm assembled width T (9 × 2.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 475 kN, C0 620 kN, grease limiting speed 1,400 r/min, oil speed 1,900 r/min, mass about 8830 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HM926747/HM926710 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HM926747 cone or the HM926710 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 475/620 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HM926747/HM926710 and a metric ISO 355 tapered bearing?", "a": "4T-HM926747/HM926710 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 127×228.6×53.975 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HM926747/HM926710 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HM926747/HM926710 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HM926747/HM926710 list two speeds, 1,400 and 1,900 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HM926747/HM926710 at 1,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HM926747", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hm926747-hm926710", "hm926747-hm926710", "HM926747-HM926710", "4T-HM926747-HM926710" ], "locale_variants": {} }, { "sku": "95500-95905", "brand": "NTN", "manufacturer_designation": "NTN 4T-95500/95905", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 127, "D_mm": 230, "B_mm": 63.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 580, "static_load_kN": 825, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 12900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-95500/95905 is the NTN 4T catalogue entry for a 127×230×63.5 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-95500/95905 are separately stocked parts: a worn 95905 cup can be replaced against the existing 95500 cone, provided the new cup carries the identical reference — pairing across references changes the 63.5 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 63.5 mm T of each 4T-95500/95905 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for 95905: within the pure-numeric inch family tables the 95500 cone is listed against several cup options, and it is the cup that fixes the 230 mm OD and the 63.5 mm assembled width — quote the full 95500/95905 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-95500/95905, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "At 127 mm bore the 4T-95500/95905 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 580 kN C level.", "The pure-numeric inch family at 127 mm bore (230×63.5 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 95500/95905 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 95500 and 95905; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full 95500/95905 pair at ordering: the 95500 cone also ships against sibling cups, and a cup from another reference changes the 63.5 mm assembled width and the rating.", "Replacing one half of an adjusted pair without resetting end play negates the 63.5 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 580/825 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-95500/95905; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-95500/95905?", "a": "4T-95500/95905 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 127 mm bore (5 in), 230 mm outside diameter and 63.5 mm assembled width T (9.055 × 2.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 580 kN, C0 825 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 12900 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-95500/95905 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 95500 cone or the 95905 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 580/825 kN ratings change with the cup." }, { "q": "What is the difference between 4T-95500/95905 and a metric ISO 355 tapered bearing?", "a": "4T-95500/95905 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 127×230×63.5 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-95500/95905 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 95500/95905 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-95500/95905 list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-95500/95905 at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "95500", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-95500-95905", "95500-95905", "4T-95500-95905" ], "locale_variants": {} }, { "sku": "HH228349-HH228310", "brand": "NTN", "manufacturer_designation": "NTN 4T-HH228349/HH228310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 127, "D_mm": 254, "B_mm": 77.788, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 8201, "static_load_kN": 70, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1900, "weight_g": 18000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-HH228349/HH228310 is the NTN 4T catalogue entry for a 127×254×77.788 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: HH228349 identifies the cone of 127 mm (5 in) bore by catalogue lookup, and HH228310 fixes the 254 mm OD. The 63.5 mm radial section over the 127 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for HH228310: within the extra-heavy HH family tables the HH228349 cone is listed against several cup options, and it is the cup that fixes the 254 mm OD and the 77.788 mm assembled width — quote the full HH228349/HH228310 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-HH228349/HH228310, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 127 mm bore the 4T-HH228349/HH228310 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 8201 kN C level.", "The extra-heavy HH family is proportioned for a high thrust share; swapping to a lighter LM or pure-numeric series at the same 127 mm bore cuts axial capacity even when the envelope fits — re-verify the load split before downgrading.", "Fit selection follows the rotating ring: a rotating cone on a 127 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of HH228349 and HH228310; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full HH228349/HH228310 pair at ordering: the HH228349 cone also ships against sibling cups, and a cup from another reference changes the 77.788 mm assembled width and the rating.", "The 8201/70 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-HH228349/HH228310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-HH228349/HH228310?", "a": "4T-HH228349/HH228310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 127 mm bore (5 in), 254 mm outside diameter and 77.788 mm assembled width T (10 × 3.063 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 8201 kN, C0 70 kN, grease limiting speed 1,400 r/min, oil speed 1,900 r/min, mass about 18000 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-HH228349/HH228310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the HH228349 cone or the HH228310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 8201/70 kN ratings change with the cup." }, { "q": "What is the difference between 4T-HH228349/HH228310 and a metric ISO 355 tapered bearing?", "a": "4T-HH228349/HH228310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 127×254×77.788 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-HH228349/HH228310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare HH228349/HH228310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-HH228349/HH228310 list two speeds, 1,400 and 1,900 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-HH228349/HH228310 at 1,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "HH228349", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-hh228349-hh228310", "hh228349-hh228310", "HH228349-HH228310", "4T-HH228349-HH228310" ], "locale_variants": {} }, { "sku": "799-792", "brand": "NTN", "manufacturer_designation": "NTN 4T-799/792", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 128.588, "D_mm": 206.375, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 350, "static_load_kN": 520, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 5770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 128.588 mm carrying combined radial and thrust load, NTN lists 4T-799/792, a single-row 4T tapered roller set of 350 kN C and 520 kN C0 inside the 206.375 mm OD cup. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 799 sits in the pure-numeric inch family. Grease relubrication at the 1,700 r/min limiting speed targets the cone-rib contact; sustaining 2,200 r/min needs an oil supply directed at the large roller ends. Cup-side note for 792: within the pure-numeric inch family tables the 799 cone is listed against several cup options, and it is the cup that fixes the 206.375 mm OD and the 47.625 mm assembled width — quote the full 799/792 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 128.588 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "At 128.588 mm bore the 4T-799/792 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 350 kN C level.", "The pure-numeric inch family at 128.588 mm bore (206.375×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 799/792 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 799 and 792; use undercut shoulders so the rings seat on the face, not on a radius.", "ABMA makes the 128.588×206.375 mm envelope interchangeable, not the ratings: NTN prints 350/520 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 128.588×206.375 mm envelope interchangeable, not the ratings: NTN prints 350/520 kN for this execution and another make of the same number can differ in roller complement.", "The 350/520 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-799/792; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-799/792?", "a": "4T-799/792 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 128.588 mm bore (5.063 in), 206.375 mm outside diameter and 47.625 mm assembled width T (8.125 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 350 kN, C0 520 kN, grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 5770 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-799/792 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 799 cone or the 792 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 350/520 kN ratings change with the cup." }, { "q": "What is the difference between 4T-799/792 and a metric ISO 355 tapered bearing?", "a": "4T-799/792 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 128.588×206.375×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-799/792 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 799/792 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-799/792 list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-799/792 at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "799", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-799-792", "799-792", "4T-799-792" ], "locale_variants": {} }, { "sku": "67389-67322", "brand": "NTN", "manufacturer_designation": "NTN 4T-67389/67322", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 130.175, "D_mm": 196.85, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 340, "static_load_kN": 550, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 4870, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 130.175 mm carrying combined radial and thrust load, NTN lists 4T-67389/67322, a single-row 4T tapered roller set of 340 kN C and 550 kN C0 inside the 196.85 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 67389 identifies the cone of 130.175 mm (5.125 in) bore by catalogue lookup, and 67322 fixes the 196.85 mm OD. Speed planning uses both catalogue columns: grease 1,700 r/min is the mechanical ceiling for 4T-67389/67322, oil 2,200 r/min with circulating oil — a 500 r/min margin at this size. Housing fitment sequence for 4T-67389/67322: press the 67322 cup square into the 196.85 mm seat first, then bring the 67389 cone (on its 130.175 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Running clearance of 4T-67389/67322 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 130.175 mm bore the 4T-67389/67322 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 340 kN C level.", "The pure-numeric inch family at 130.175 mm bore (196.85×46.038 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 67389/67322 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 46.038 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Inch and metric bores collide on paper — 130.175 mm is 5.125 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Fit selection follows the rotating ring: a rotating cone on a 130.175 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 340/550 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-67389/67322; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-67389/67322?", "a": "4T-67389/67322 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 130.175 mm bore (5.125 in), 196.85 mm outside diameter and 46.038 mm assembled width T (7.75 × 1.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 340 kN, C0 550 kN, grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 4870 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-67389/67322 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 67389 cone or the 67322 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 340/550 kN ratings change with the cup." }, { "q": "What is the difference between 4T-67389/67322 and a metric ISO 355 tapered bearing?", "a": "4T-67389/67322 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 130.175×196.85×46.038 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-67389/67322 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 67389/67322 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-67389/67322 list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-67389/67322 at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "67389", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-67389-67322", "67389-67322", "4T-67389-67322" ], "locale_variants": {} }, { "sku": "799A-792", "brand": "NTN", "manufacturer_designation": "NTN 4T-799A/792", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 130.175, "D_mm": 206.375, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 350, "static_load_kN": 520, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 5650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 130.175 mm carrying combined radial and thrust load, NTN lists 4T-799A/792, a single-row 4T tapered roller set of 350 kN C and 520 kN C0 inside the 206.375 mm OD cup. Reading the designation: 4T-799A/792 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 1,700 r/min limiting speed targets the cone-rib contact; sustaining 2,200 r/min needs an oil supply directed at the large roller ends. The printed 350/520 kN ratings belong to the assembled 799A+792 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-799A/792, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 130.175 mm bore the 4T-799A/792 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 350 kN C level.", "The pure-numeric inch family at 130.175 mm bore (206.375×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 799A/792 reference at purchase.", "Never drive the 206.375 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Do not confuse T (47.625 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "An unloaded 4T-799A/792 near 1,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 350/520 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-799A/792; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-799A/792?", "a": "4T-799A/792 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 130.175 mm bore (5.125 in), 206.375 mm outside diameter and 47.625 mm assembled width T (8.125 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 350 kN, C0 520 kN, grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 5650 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-799A/792 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 799A cone or the 792 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 350/520 kN ratings change with the cup." }, { "q": "What is the difference between 4T-799A/792 and a metric ISO 355 tapered bearing?", "a": "4T-799A/792 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 130.175×206.375×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-799A/792 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 799A/792 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-799A/792 list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-799A/792 at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "799A", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-799a-792", "799a-792", "799A-792", "4T-799A-792" ], "locale_variants": {} }, { "sku": "L327249-L327210", "brand": "NTN", "manufacturer_designation": "NTN 4T-L327249/L327210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 133.35, "D_mm": 177.008, "B_mm": 25.4, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 140, "static_load_kN": 259, "limiting_speed_rpm": 1800, "max_rpm": 1800, "speed_oil_rpm": 2400, "weight_g": 1700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-L327249/L327210 belongs to the NTN inch 4T tapered roller range (light L family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — L327249 sits in the light L family. Contact-angle geometry of the light L family gives 4T-L327249/L327210 its radial/axial load split — at 140/259 kN the static rating is about 1.85× C, typical of inch tapered sets proportioned for combined duty. Cup-side note for L327210: within the light L family tables the L327249 cone is listed against several cup options, and it is the cup that fixes the 177.008 mm OD and the 25.4 mm assembled width — quote the full L327249/L327210 pair, never the cone alone. Fillet radii must clear the chamfers of the L327249 cone and L327210 cup; undercut shoulders seat the rings fully instead of bridging on a radius.", "applications": [ "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "At 133.35 mm bore the 4T-L327249/L327210 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 140 kN C level.", "The light L family at 133.35 mm bore (177.008×25.4 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L327249/L327210 reference at purchase.", "Open 4T-L327249/L327210 sets have no seals: a hub or gearbox needs external sealing or the 1,800 r/min grease figure is meaningless once water reaches the cone rib.", "Replacing one half of an adjusted pair without resetting end play negates the 25.4 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "ABMA makes the 133.35×177.008 mm envelope interchangeable, not the ratings: NTN prints 140/259 kN for this execution and another make of the same number can differ in roller complement.", "The 140/259 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L327249/L327210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L327249/L327210?", "a": "4T-L327249/L327210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 133.35 mm bore (5.25 in), 177.008 mm outside diameter and 25.4 mm assembled width T (6.969 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 140 kN, C0 259 kN, grease limiting speed 1,800 r/min, oil speed 2,400 r/min, mass about 1700 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L327249/L327210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L327249 cone or the L327210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 140/259 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L327249/L327210 and a metric ISO 355 tapered bearing?", "a": "4T-L327249/L327210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 133.35×177.008×25.4 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L327249/L327210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L327249/L327210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L327249/L327210 list two speeds, 1,800 and 2,400 r/min?", "a": "The lower figure, 1,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L327249/L327210 at 2,400 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L327249-210", "equiv_brand": "SKF", "level": "partial", "note": "Same 133.35×177.008×25.4 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=192", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l327249-l327210", "l327249-l327210", "L327249-L327210", "4T-L327249-L327210" ], "locale_variants": {} }, { "sku": "48385-48320", "brand": "NTN", "manufacturer_designation": "NTN 4T-48385/48320", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 133.35, "D_mm": 190.5, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 262, "static_load_kN": 475, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2300, "weight_g": 3640, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-48385/48320 is the NTN 4T catalogue entry for a 133.35×190.5×39.688 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 48385/48320 without it. Grease relubrication at the 1,700 r/min limiting speed targets the cone-rib contact; sustaining 2,300 r/min needs an oil supply directed at the large roller ends. The printed 262/475 kN ratings belong to the assembled 48385+48320 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-48385/48320 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 133.35 mm bore the 4T-48385/48320 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 262 kN C level.", "The pure-numeric inch family at 133.35 mm bore (190.5×39.688 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 48385/48320 reference at purchase.", "Quote the full 48385/48320 pair at ordering: the 48385 cone also ships against sibling cups, and a cup from another reference changes the 39.688 mm assembled width and the rating.", "Grease packs must leave free volume inside the 39.688 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,300 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of 48385 and 48320; use undercut shoulders so the rings seat on the face, not on a radius.", "The 262/475 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-48385/48320; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-48385/48320?", "a": "4T-48385/48320 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 133.35 mm bore (5.25 in), 190.5 mm outside diameter and 39.688 mm assembled width T (7.5 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 262 kN, C0 475 kN, grease limiting speed 1,700 r/min, oil speed 2,300 r/min, mass about 3640 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-48385/48320 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 48385 cone or the 48320 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 262/475 kN ratings change with the cup." }, { "q": "What is the difference between 4T-48385/48320 and a metric ISO 355 tapered bearing?", "a": "4T-48385/48320 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 133.35×190.5×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-48385/48320 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 48385/48320 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-48385/48320 list two speeds, 1,700 and 2,300 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-48385/48320 at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "48385", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-48385-48320", "48385-48320", "4T-48385-48320" ], "locale_variants": {} }, { "sku": "67390-67322", "brand": "NTN", "manufacturer_designation": "NTN 4T-67390/67322", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 133.35, "D_mm": 196.85, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 340, "static_load_kN": 550, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 4630, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-67390/67322 at 133.35 mm bore (5.25 in), 196.85 mm cup OD and 46.038 mm assembled T, with a grease limiting speed of 1,700 r/min and an oil ceiling of 2,200 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 67390/67322 without it. Speed planning uses both catalogue columns: grease 1,700 r/min is the mechanical ceiling for 4T-67390/67322, oil 2,200 r/min with circulating oil — a 500 r/min margin at this size. Housing fitment sequence for 4T-67390/67322: press the 67322 cup square into the 196.85 mm seat first, then bring the 67390 cone (on its 133.35 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-67390/67322 run near 1,700 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 133.35 mm bore the 4T-67390/67322 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 340 kN C level.", "The pure-numeric inch family at 133.35 mm bore (196.85×46.038 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 67390/67322 reference at purchase.", "Grease packs must leave free volume inside the 46.038 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,200 r/min raises temperature and destroys the setting.", "Quote the full 67390/67322 pair at ordering: the 67390 cone also ships against sibling cups, and a cup from another reference changes the 46.038 mm assembled width and the rating.", "ABMA makes the 133.35×196.85 mm envelope interchangeable, not the ratings: NTN prints 340/550 kN for this execution and another make of the same number can differ in roller complement.", "The 340/550 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-67390/67322; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-67390/67322?", "a": "4T-67390/67322 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 133.35 mm bore (5.25 in), 196.85 mm outside diameter and 46.038 mm assembled width T (7.75 × 1.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 340 kN, C0 550 kN, grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 4630 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-67390/67322 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 67390 cone or the 67322 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 340/550 kN ratings change with the cup." }, { "q": "What is the difference between 4T-67390/67322 and a metric ISO 355 tapered bearing?", "a": "4T-67390/67322 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 133.35×196.85×46.038 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-67390/67322 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 67390/67322 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-67390/67322 list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-67390/67322 at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "67390", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-67390-67322", "67390-67322", "4T-67390-67322" ], "locale_variants": {} }, { "sku": "67391-67322-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-67391/67322", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 133.35, "D_mm": 196.85, "B_mm": 46.038, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 340, "static_load_kN": 550, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2200, "weight_g": 4590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 5.25 in (133.35 mm) shaft position as 4T-67391/67322: cone 67391, cup 67322, profiled rollers and a pressed-steel cage, rated 340 kN basic dynamic and 550 kN static. Cone and cup of 4T-67391/67322 are separately stocked parts: a worn 67322 cup can be replaced against the existing 67391 cone, provided the new cup carries the identical reference — pairing across references changes the 46.038 mm assembled width and the rating. Contact-angle geometry of the pure-numeric inch family gives 4T-67391/67322 its radial/axial load split — at 340/550 kN the static rating is about 1.62× C, typical of inch tapered sets proportioned for combined duty. The printed 340/550 kN ratings belong to the assembled 67391+67322 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. After bedding-in, re-check the end play of the adjusted 4T-67391/67322 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 133.35 mm bore the 4T-67391/67322 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 340 kN C level.", "The pure-numeric inch family at 133.35 mm bore (196.85×46.038 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 67391/67322 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 133.35 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Replacing one half of an adjusted pair without resetting end play negates the 46.038 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 133.35 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 340/550 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-67391/67322; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-67391/67322?", "a": "4T-67391/67322 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 133.35 mm bore (5.25 in), 196.85 mm outside diameter and 46.038 mm assembled width T (7.75 × 1.813 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 340 kN, C0 550 kN, grease limiting speed 1,700 r/min, oil speed 2,200 r/min, mass about 4590 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-67391/67322 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 67391 cone or the 67322 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 340/550 kN ratings change with the cup." }, { "q": "What is the difference between 4T-67391/67322 and a metric ISO 355 tapered bearing?", "a": "4T-67391/67322 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 133.35×196.85×46.038 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-67391/67322 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 67391/67322 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-67391/67322 list two speeds, 1,700 and 2,200 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-67391/67322 at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "67391-67322", "equiv_brand": "SKF", "level": "partial", "note": "Same 133.35×196.85×46.038 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-67391-67322", "67391-67322", "4T-67391-67322", "67391-67322-NTN" ], "locale_variants": {} }, { "sku": "74525-74850", "brand": "NTN", "manufacturer_designation": "NTN 4T-74525/74850", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 133.35, "D_mm": 215.9, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 355, "static_load_kN": 540, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2100, "weight_g": 6560, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 133.35 mm carrying combined radial and thrust load, NTN lists 4T-74525/74850, a single-row 4T tapered roller set of 355 kN C and 540 kN C0 inside the 215.9 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 74525 identifies the cone of 133.35 mm (5.25 in) bore by catalogue lookup, and 74850 fixes the 215.9 mm OD. Selection: C 355 kN against C0 540 kN gives a C0/C ratio of 1.52 for the 133.35 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for 74850: within the pure-numeric inch family tables the 74525 cone is listed against several cup options, and it is the cup that fixes the 215.9 mm OD and the 47.625 mm assembled width — quote the full 74525/74850 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-74525/74850 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "At 133.35 mm bore the 4T-74525/74850 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 355 kN C level.", "The pure-numeric inch family at 133.35 mm bore (215.9×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 74525/74850 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 47.625 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Replacing one half of an adjusted pair without resetting end play negates the 47.625 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 133.35 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "The 355/540 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-74525/74850; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-74525/74850?", "a": "4T-74525/74850 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 133.35 mm bore (5.25 in), 215.9 mm outside diameter and 47.625 mm assembled width T (8.5 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 355 kN, C0 540 kN, grease limiting speed 1,600 r/min, oil speed 2,100 r/min, mass about 6560 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-74525/74850 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 74525 cone or the 74850 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 355/540 kN ratings change with the cup." }, { "q": "What is the difference between 4T-74525/74850 and a metric ISO 355 tapered bearing?", "a": "4T-74525/74850 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 133.35×215.9×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-74525/74850 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 74525/74850 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-74525/74850 list two speeds, 1,600 and 2,100 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-74525/74850 at 2,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "74525", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-74525-74850", "74525-74850", "4T-74525-74850" ], "locale_variants": {} }, { "sku": "48393-48320", "brand": "NTN", "manufacturer_designation": "NTN 4T-48393/48320", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 136.525, "D_mm": 190.5, "B_mm": 39.688, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 262, "static_load_kN": 475, "limiting_speed_rpm": 1700, "max_rpm": 1700, "speed_oil_rpm": 2300, "weight_g": 3430, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 136.525 mm carrying combined radial and thrust load, NTN lists 4T-48393/48320, a single-row 4T tapered roller set of 262 kN C and 475 kN C0 inside the 190.5 mm OD cup. Reading the designation: 4T-48393/48320 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Selection: C 262 kN against C0 475 kN gives a C0/C ratio of 1.81 for the 136.525 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-48393/48320: press the 48320 cup square into the 190.5 mm seat first, then bring the 48393 cone (on its 136.525 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Minimum load matters at speed: an unloaded 4T-48393/48320 run near 1,700 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 136.525 mm bore the 4T-48393/48320 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 262 kN C level.", "The pure-numeric inch family at 136.525 mm bore (190.5×39.688 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 48393/48320 reference at purchase.", "ABMA makes the 136.525×190.5 mm envelope interchangeable, not the ratings: NTN prints 262/475 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 136.525×190.5 mm envelope interchangeable, not the ratings: NTN prints 262/475 kN for this execution and another make of the same number can differ in roller complement.", "Shaft and housing fillets must clear the ring chamfers of 48393 and 48320; use undercut shoulders so the rings seat on the face, not on a radius.", "The 262/475 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-48393/48320; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-48393/48320?", "a": "4T-48393/48320 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 136.525 mm bore (5.375 in), 190.5 mm outside diameter and 39.688 mm assembled width T (7.5 × 1.563 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 262 kN, C0 475 kN, grease limiting speed 1,700 r/min, oil speed 2,300 r/min, mass about 3430 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-48393/48320 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 48393 cone or the 48320 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 262/475 kN ratings change with the cup." }, { "q": "What is the difference between 4T-48393/48320 and a metric ISO 355 tapered bearing?", "a": "4T-48393/48320 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 136.525×190.5×39.688 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-48393/48320 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 48393/48320 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-48393/48320 list two speeds, 1,700 and 2,300 r/min?", "a": "The lower figure, 1,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-48393/48320 at 2,300 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "48393", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-48393-48320", "48393-48320", "4T-48393-48320" ], "locale_variants": {} }, { "sku": "74550-74850", "brand": "NTN", "manufacturer_designation": "NTN 4T-74550/74850", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 136.525, "D_mm": 215.9, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 355, "static_load_kN": 540, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2100, "weight_g": 6050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-74550/74850 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 74550 and cup 74850 delivered as a matched, separable pair of 136.525 mm bore and 215.9 mm outside diameter. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 74550 sits in the pure-numeric inch family. Catalogue mass of the 4T-74550/74850 cone-plus-cup set is 6050 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-74550/74850: press the 74850 cup square into the 215.9 mm seat first, then bring the 74550 cone (on its 136.525 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 136.525 mm cone with an induction heater (max 120 °C) and press the 215.9 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.", "applications": [ "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 136.525 mm bore the 4T-74550/74850 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 355 kN C level.", "The pure-numeric inch family at 136.525 mm bore (215.9×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 74550/74850 reference at purchase.", "Replacing one half of an adjusted pair without resetting end play negates the 47.625 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "Fit selection follows the rotating ring: a rotating cone on a 136.525 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 136.525×215.9 mm envelope interchangeable, not the ratings: NTN prints 355/540 kN for this execution and another make of the same number can differ in roller complement.", "The 355/540 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-74550/74850; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-74550/74850?", "a": "4T-74550/74850 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 136.525 mm bore (5.375 in), 215.9 mm outside diameter and 47.625 mm assembled width T (8.5 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 355 kN, C0 540 kN, grease limiting speed 1,600 r/min, oil speed 2,100 r/min, mass about 6050 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-74550/74850 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 74550 cone or the 74850 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 355/540 kN ratings change with the cup." }, { "q": "What is the difference between 4T-74550/74850 and a metric ISO 355 tapered bearing?", "a": "4T-74550/74850 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 136.525×215.9×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-74550/74850 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 74550/74850 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-74550/74850 list two speeds, 1,600 and 2,100 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-74550/74850 at 2,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "74550", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-74550-74850", "74550-74850", "4T-74550-74850" ], "locale_variants": {} }, { "sku": "896-892", "brand": "NTN", "manufacturer_designation": "NTN 4T-896/892", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 136.525, "D_mm": 228.6, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 495, "static_load_kN": 735, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 9120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-896/892 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 136.525×228.6×57.15 mm (assembled width T), for a shaft of about 136.525 mm (5.375 in). Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 896 identifies the cone of 136.525 mm (5.375 in) bore by catalogue lookup, and 892 fixes the 228.6 mm OD. Grease relubrication at the 1,500 r/min limiting speed targets the cone-rib contact; sustaining 2,000 r/min needs an oil supply directed at the large roller ends. Cup-side note for 892: within the pure-numeric inch family tables the 896 cone is listed against several cup options, and it is the cup that fixes the 228.6 mm OD and the 57.15 mm assembled width — quote the full 896/892 pair, never the cone alone. With a rotating shaft a m6/n6 cone seat and an easy-push cup seat are typical practice for 4T-896/892; reverse the fit logic when the cup rotates.", "applications": [ "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 136.525 mm bore the 4T-896/892 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 495 kN C level.", "The pure-numeric inch family at 136.525 mm bore (228.6×57.15 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 896/892 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 136.525 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "ABMA makes the 136.525×228.6 mm envelope interchangeable, not the ratings: NTN prints 495/735 kN for this execution and another make of the same number can differ in roller complement.", "Replacing one half of an adjusted pair without resetting end play negates the 57.15 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.", "The 495/735 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-896/892; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-896/892?", "a": "4T-896/892 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 136.525 mm bore (5.375 in), 228.6 mm outside diameter and 57.15 mm assembled width T (9 × 2.25 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 495 kN, C0 735 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 9120 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-896/892 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 896 cone or the 892 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 495/735 kN ratings change with the cup." }, { "q": "What is the difference between 4T-896/892 and a metric ISO 355 tapered bearing?", "a": "4T-896/892 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 136.525×228.6×57.15 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-896/892 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 896/892 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-896/892 list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-896/892 at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "896", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-896-892", "896-892", "4T-896-892" ], "locale_variants": {} }, { "sku": "95525-95925-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-95525/95925", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 136.525, "D_mm": 234.95, "B_mm": 63.5, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 580, "static_load_kN": 825, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 11300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-95525/95925 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 136.525×234.95×63.5 mm (assembled width T), for a shaft of about 136.525 mm (5.375 in). Cone and cup of 4T-95525/95925 are separately stocked parts: a worn 95925 cup can be replaced against the existing 95525 cone, provided the new cup carries the identical reference — pairing across references changes the 63.5 mm assembled width and the rating. Catalogue mass of the 4T-95525/95925 cone-plus-cup set is 11300 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-95525/95925: press the 95925 cup square into the 234.95 mm seat first, then bring the 95525 cone (on its 136.525 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Contact-pattern check with marking blue: a pattern biased to one roller end means the 136.525 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 136.525 mm bore the 4T-95525/95925 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 580 kN C level.", "The pure-numeric inch family at 136.525 mm bore (234.95×63.5 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 95525/95925 reference at purchase.", "Shaft and housing fillets must clear the ring chamfers of 95525 and 95925; use undercut shoulders so the rings seat on the face, not on a radius.", "Open 4T-95525/95925 sets have no seals: a hub or gearbox needs external sealing or the 1,500 r/min grease figure is meaningless once water reaches the cone rib.", "Never drive the 234.95 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "The 580/825 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-95525/95925; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-95525/95925?", "a": "4T-95525/95925 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 136.525 mm bore (5.375 in), 234.95 mm outside diameter and 63.5 mm assembled width T (9.25 × 2.5 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 580 kN, C0 825 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 11300 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-95525/95925 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 95525 cone or the 95925 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 580/825 kN ratings change with the cup." }, { "q": "What is the difference between 4T-95525/95925 and a metric ISO 355 tapered bearing?", "a": "4T-95525/95925 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 136.525×234.95×63.5 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-95525/95925 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 95525/95925 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-95525/95925 list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-95525/95925 at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "95525-95925", "equiv_brand": "SKF", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-95525-95925", "95525-95925", "4T-95525-95925", "95525-95925-NTN" ], "locale_variants": {} }, { "sku": "898-892-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-898/892", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 139.7, "D_mm": 228.6, "B_mm": 57.15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 495, "static_load_kN": 735, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 8810, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-898/892 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 898 and cup 892 delivered as a matched, separable pair of 139.7 mm bore and 228.6 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 898 identifies the cone of 139.7 mm (5.5 in) bore by catalogue lookup, and 892 fixes the 228.6 mm OD. Grease relubrication at the 1,500 r/min limiting speed targets the cone-rib contact; sustaining 2,000 r/min needs an oil supply directed at the large roller ends. The printed 495/735 kN ratings belong to the assembled 898+892 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-898/892 run near 1,500 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 139.7 mm bore the 4T-898/892 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 495 kN C level.", "The pure-numeric inch family at 139.7 mm bore (228.6×57.15 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 898/892 reference at purchase.", "Never drive the 228.6 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume inside the 57.15 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,000 r/min raises temperature and destroys the setting.", "An unloaded 4T-898/892 near 1,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 495/735 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-898/892; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-898/892?", "a": "4T-898/892 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 139.7 mm bore (5.5 in), 228.6 mm outside diameter and 57.15 mm assembled width T (9 × 2.25 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 495 kN, C0 735 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 8810 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-898/892 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 898 cone or the 892 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 495/735 kN ratings change with the cup." }, { "q": "What is the difference between 4T-898/892 and a metric ISO 355 tapered bearing?", "a": "4T-898/892 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 139.7×228.6×57.15 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-898/892 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 898/892 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-898/892 list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-898/892 at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "898-892", "equiv_brand": "SKF", "level": "partial", "note": "Same 139.7×228.6×57.15 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-898-892", "898-892", "4T-898-892", "898-892-NTN" ], "locale_variants": {} }, { "sku": "36690-36620", "brand": "NTN", "manufacturer_designation": "NTN 4T-36690/36620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 142.875, "D_mm": 193.675, "B_mm": 28.575, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 183, "static_load_kN": 340, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2200, "weight_g": 2260, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-36690/36620 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 142.875×193.675×28.575 mm (assembled width T), for a shaft of about 142.875 mm (5.625 in). The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 36690/36620 without it. Grease relubrication at the 1,600 r/min limiting speed targets the cone-rib contact; sustaining 2,200 r/min needs an oil supply directed at the large roller ends. The printed 183/340 kN ratings belong to the assembled 36690+36620 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Running clearance of 4T-36690/36620 is set at mounting by axial displacement of cone or cup — the catalogue does not ship a preloaded set, so the drawing must state end play or preload.", "applications": [ "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 142.875 mm bore the 4T-36690/36620 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 183 kN C level.", "The pure-numeric inch family at 142.875 mm bore (193.675×28.575 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 36690/36620 reference at purchase.", "Inch and metric bores collide on paper — 142.875 mm is 5.625 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "ABMA makes the 142.875×193.675 mm envelope interchangeable, not the ratings: NTN prints 183/340 kN for this execution and another make of the same number can differ in roller complement.", "Quote the full 36690/36620 pair at ordering: the 36690 cone also ships against sibling cups, and a cup from another reference changes the 28.575 mm assembled width and the rating.", "The 183/340 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-36690/36620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-36690/36620?", "a": "4T-36690/36620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 142.875 mm bore (5.625 in), 193.675 mm outside diameter and 28.575 mm assembled width T (7.625 × 1.125 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 183 kN, C0 340 kN, grease limiting speed 1,600 r/min, oil speed 2,200 r/min, mass about 2260 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-36690/36620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 36690 cone or the 36620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 183/340 kN ratings change with the cup." }, { "q": "What is the difference between 4T-36690/36620 and a metric ISO 355 tapered bearing?", "a": "4T-36690/36620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 142.875×193.675×28.575 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-36690/36620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 36690/36620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-36690/36620 list two speeds, 1,600 and 2,200 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-36690/36620 at 2,200 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "36690", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-36690-36620", "36690-36620", "4T-36690-36620" ], "locale_variants": {} }, { "sku": "48684-48620", "brand": "NTN", "manufacturer_designation": "NTN 4T-48684/48620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 142.875, "D_mm": 200.025, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 265, "static_load_kN": 490, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2100, "weight_g": 3850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-48684/48620 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 142.875×200.025×41.275 mm (assembled width T), for a shaft of about 142.875 mm (5.625 in). Reading the designation: 4T-48684/48620 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Grease relubrication at the 1,600 r/min limiting speed targets the cone-rib contact; sustaining 2,100 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-48684/48620: press the 48620 cup square into the 200.025 mm seat first, then bring the 48684 cone (on its 142.875 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a m6/n6 cone seat and an easy-push cup seat are typical practice for 4T-48684/48620; reverse the fit logic when the cup rotates.", "applications": [ "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 142.875 mm bore the 4T-48684/48620 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 265 kN C level.", "The pure-numeric inch family at 142.875 mm bore (200.025×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 48684/48620 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 142.875 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Open 4T-48684/48620 sets have no seals: a hub or gearbox needs external sealing or the 1,600 r/min grease figure is meaningless once water reaches the cone rib.", "Quote the full 48684/48620 pair at ordering: the 48684 cone also ships against sibling cups, and a cup from another reference changes the 41.275 mm assembled width and the rating.", "The 265/490 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-48684/48620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-48684/48620?", "a": "4T-48684/48620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 142.875 mm bore (5.625 in), 200.025 mm outside diameter and 41.275 mm assembled width T (7.875 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 265 kN, C0 490 kN, grease limiting speed 1,600 r/min, oil speed 2,100 r/min, mass about 3850 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-48684/48620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 48684 cone or the 48620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 265/490 kN ratings change with the cup." }, { "q": "What is the difference between 4T-48684/48620 and a metric ISO 355 tapered bearing?", "a": "4T-48684/48620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 142.875×200.025×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-48684/48620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 48684/48620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-48684/48620 list two speeds, 1,600 and 2,100 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-48684/48620 at 2,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "48684", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-48684-48620", "48684-48620", "4T-48684-48620" ], "locale_variants": {} }, { "sku": "48685-48620", "brand": "NTN", "manufacturer_designation": "NTN 4T-48685/48620", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 142.875, "D_mm": 200.025, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 265, "static_load_kN": 490, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2100, "weight_g": 3890, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-48685/48620 denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 48685 and cup 48620 delivered as a matched, separable pair of 142.875 mm bore and 200.025 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 48685/48620 without it. The 1.9 kN of dynamic capacity per millimetre of bore summarises the 265 kN rating over the 142.875 mm bore — sanity-check any interchange candidate against this ratio and the 41.275 mm T. Housing fitment sequence for 4T-48685/48620: press the 48620 cup square into the 200.025 mm seat first, then bring the 48685 cone (on its 142.875 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-48685/48620 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 142.875 mm bore the 4T-48685/48620 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 265 kN C level.", "The pure-numeric inch family at 142.875 mm bore (200.025×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 48685/48620 reference at purchase.", "ABMA makes the 142.875×200.025 mm envelope interchangeable, not the ratings: NTN prints 265/490 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 142.875×200.025 mm envelope interchangeable, not the ratings: NTN prints 265/490 kN for this execution and another make of the same number can differ in roller complement.", "Open 4T-48685/48620 sets have no seals: a hub or gearbox needs external sealing or the 1,600 r/min grease figure is meaningless once water reaches the cone rib.", "The 265/490 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-48685/48620; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-48685/48620?", "a": "4T-48685/48620 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 142.875 mm bore (5.625 in), 200.025 mm outside diameter and 41.275 mm assembled width T (7.875 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 265 kN, C0 490 kN, grease limiting speed 1,600 r/min, oil speed 2,100 r/min, mass about 3890 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-48685/48620 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 48685 cone or the 48620 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 265/490 kN ratings change with the cup." }, { "q": "What is the difference between 4T-48685/48620 and a metric ISO 355 tapered bearing?", "a": "4T-48685/48620 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 142.875×200.025×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-48685/48620 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 48685/48620 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-48685/48620 list two speeds, 1,600 and 2,100 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-48685/48620 at 2,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "48685", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-48685-48620", "48685-48620", "4T-48685-48620" ], "locale_variants": {} }, { "sku": "99550-99100", "brand": "NTN", "manufacturer_designation": "NTN 4T-99550/99100", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 142.875, "D_mm": 254, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 610, "static_load_kN": 910, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1800, "weight_g": 14300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-99550/99100 at 142.875 mm bore (5.625 in), 254 mm cup OD and 66.675 mm assembled T, with a grease limiting speed of 1,400 r/min and an oil ceiling of 1,800 r/min. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 99550 identifies the cone of 142.875 mm (5.625 in) bore by catalogue lookup, and 99100 fixes the 254 mm OD. The 55.6 mm radial section over the 142.875 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 610/910 kN ratings belong to the assembled 99550+99100 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 142.875 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 142.875 mm bore the 4T-99550/99100 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 610 kN C level.", "The pure-numeric inch family at 142.875 mm bore (254×66.675 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 99550/99100 reference at purchase.", "Inch and metric bores collide on paper — 142.875 mm is 5.625 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "Grease packs must leave free volume inside the 66.675 mm-wide set; over-greasing a pair churning near the oil-band speed of 1,800 r/min raises temperature and destroys the setting.", "Open 4T-99550/99100 sets have no seals: a hub or gearbox needs external sealing or the 1,400 r/min grease figure is meaningless once water reaches the cone rib.", "The 610/910 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-99550/99100; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-99550/99100?", "a": "4T-99550/99100 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 142.875 mm bore (5.625 in), 254 mm outside diameter and 66.675 mm assembled width T (10 × 2.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 610 kN, C0 910 kN, grease limiting speed 1,400 r/min, oil speed 1,800 r/min, mass about 14300 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-99550/99100 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 99550 cone or the 99100 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 610/910 kN ratings change with the cup." }, { "q": "What is the difference between 4T-99550/99100 and a metric ISO 355 tapered bearing?", "a": "4T-99550/99100 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 142.875×254×66.675 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-99550/99100 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 99550/99100 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-99550/99100 list two speeds, 1,400 and 1,800 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-99550/99100 at 1,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "99550", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-99550-99100", "99550-99100", "4T-99550-99100" ], "locale_variants": {} }, { "sku": "99575-99100", "brand": "NTN", "manufacturer_designation": "NTN 4T-99575/99100", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 146.05, "D_mm": 254, "B_mm": 66.675, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 610, "static_load_kN": 910, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1800, "weight_g": 13600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 5.75 in (146.05 mm) shaft position as 4T-99575/99100: cone 99575, cup 99100, profiled rollers and a pressed-steel cage, rated 610 kN basic dynamic and 910 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 99575/99100 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 66.675 mm T of each 4T-99575/99100 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-99575/99100: press the 99100 cup square into the 254 mm seat first, then bring the 99575 cone (on its 146.05 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-99575/99100 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 146.05 mm bore the 4T-99575/99100 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 610 kN C level.", "The pure-numeric inch family at 146.05 mm bore (254×66.675 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 99575/99100 reference at purchase.", "ABMA makes the 146.05×254 mm envelope interchangeable, not the ratings: NTN prints 610/910 kN for this execution and another make of the same number can differ in roller complement.", "Never drive the 254 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 146.05×254 mm envelope interchangeable, not the ratings: NTN prints 610/910 kN for this execution and another make of the same number can differ in roller complement.", "The 610/910 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-99575/99100; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-99575/99100?", "a": "4T-99575/99100 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 146.05 mm bore (5.75 in), 254 mm outside diameter and 66.675 mm assembled width T (10 × 2.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 610 kN, C0 910 kN, grease limiting speed 1,400 r/min, oil speed 1,800 r/min, mass about 13600 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-99575/99100 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 99575 cone or the 99100 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 610/910 kN ratings change with the cup." }, { "q": "What is the difference between 4T-99575/99100 and a metric ISO 355 tapered bearing?", "a": "4T-99575/99100 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 146.05×254×66.675 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-99575/99100 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 99575/99100 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-99575/99100 list two speeds, 1,400 and 1,800 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-99575/99100 at 1,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "99575", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-99575-99100", "99575-99100", "4T-99575-99100" ], "locale_variants": {} }, { "sku": "L630349-L630310", "brand": "NTN", "manufacturer_designation": "NTN 4T-L630349/L630310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 152.4, "D_mm": 192.088, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 144, "static_load_kN": 261, "limiting_speed_rpm": 1600, "max_rpm": 1600, "speed_oil_rpm": 2100, "weight_g": 1570, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-L630349/L630310 is the NTN 4T catalogue entry for a 152.4×192.088×25 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: L630349 identifies the cone of 152.4 mm (6 in) bore by catalogue lookup, and L630310 fixes the 192.088 mm OD. Imperial cross-check for the drawing: 152.4×192.088×25 mm converts to 6 × 7.563 × 0.984 in; the ABMA envelope swaps with like-numbered inch parts but the 144/261 kN ratings are NTN-specific. Cup-side note for L630310: within the light L family tables the L630349 cone is listed against several cup options, and it is the cup that fixes the 192.088 mm OD and the 25 mm assembled width — quote the full L630349/L630310 pair, never the cone alone. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-L630349/L630310, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "pressed-steel cage pocket wear from roller skid at light radial load and high speed", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 152.4 mm bore the 4T-L630349/L630310 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 144 kN C level.", "The light L family at 152.4 mm bore (192.088×25 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L630349/L630310 reference at purchase.", "Never drive the 192.088 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume inside the 25 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,100 r/min raises temperature and destroys the setting.", "Grease packs must leave free volume inside the 25 mm-wide set; over-greasing a pair churning near the oil-band speed of 2,100 r/min raises temperature and destroys the setting.", "The 144/261 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L630349/L630310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L630349/L630310?", "a": "4T-L630349/L630310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 152.4 mm bore (6 in), 192.088 mm outside diameter and 25 mm assembled width T (7.563 × 0.984 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 144 kN, C0 261 kN, grease limiting speed 1,600 r/min, oil speed 2,100 r/min, mass about 1570 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L630349/L630310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L630349 cone or the L630310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 144/261 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L630349/L630310 and a metric ISO 355 tapered bearing?", "a": "4T-L630349/L630310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 152.4×192.088×25 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L630349/L630310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L630349/L630310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L630349/L630310 list two speeds, 1,600 and 2,100 r/min?", "a": "The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L630349/L630310 at 2,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L630349", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l630349-l630310", "l630349-l630310", "L630349-L630310", "4T-L630349-L630310" ], "locale_variants": {} }, { "sku": "M231648-M231610", "brand": "NTN", "manufacturer_designation": "NTN 4T-M231648/M231610", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 152.4, "D_mm": 222.25, "B_mm": 46.83, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 350, "static_load_kN": 585, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 5700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 6 in (152.4 mm) shaft position as 4T-M231648/M231610: cone M231648, cup M231610, profiled rollers and a pressed-steel cage, rated 350 kN basic dynamic and 585 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote M231648/M231610 without it. The 34.9 mm radial section over the 152.4 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 350/585 kN ratings belong to the assembled M231648+M231610 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-M231648/M231610 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 152.4 mm bore the 4T-M231648/M231610 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 350 kN C level.", "The medium M family at 152.4 mm bore (222.25×46.83 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full M231648/M231610 reference at purchase.", "Never drive the 222.25 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "ABMA makes the 152.4×222.25 mm envelope interchangeable, not the ratings: NTN prints 350/585 kN for this execution and another make of the same number can differ in roller complement.", "Open 4T-M231648/M231610 sets have no seals: a hub or gearbox needs external sealing or the 1,500 r/min grease figure is meaningless once water reaches the cone rib.", "The 350/585 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-M231648/M231610; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-M231648/M231610?", "a": "4T-M231648/M231610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 152.4 mm bore (6 in), 222.25 mm outside diameter and 46.83 mm assembled width T (8.75 × 1.844 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 350 kN, C0 585 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 5700 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-M231648/M231610 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the M231648 cone or the M231610 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 350/585 kN ratings change with the cup." }, { "q": "What is the difference between 4T-M231648/M231610 and a metric ISO 355 tapered bearing?", "a": "4T-M231648/M231610 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 152.4×222.25×46.83 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-M231648/M231610 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare M231648/M231610 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-M231648/M231610 list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-M231648/M231610 at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "M231648", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-m231648-m231610", "m231648-m231610", "M231648-M231610", "4T-M231648-M231610" ], "locale_variants": {} }, { "sku": "L432349-L432310", "brand": "NTN", "manufacturer_designation": "NTN 4T-L432349/L432310", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 158.75, "D_mm": 205.583, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 140, "static_load_kN": 247, "limiting_speed_rpm": 1500, "max_rpm": 1500, "speed_oil_rpm": 2000, "weight_g": 1890, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 158.75 mm carrying combined radial and thrust load, NTN lists 4T-L432349/L432310, a single-row 4T tapered roller set of 140 kN C and 247 kN C0 inside the 205.583 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: L432349 identifies the cone of 158.75 mm (6.25 in) bore by catalogue lookup, and L432310 fixes the 205.583 mm OD. The 0.9 kN of dynamic capacity per millimetre of bore summarises the 140 kN rating over the 158.75 mm bore — sanity-check any interchange candidate against this ratio and the 23.812 mm T. The printed 140/247 kN ratings belong to the assembled L432349+L432310 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. A single-row tapered bearing reacts thrust in one direction only; 4T-L432349/L432310 is adjusted against a second bearing so the shaft is located in both directions.", "applications": [ "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 158.75 mm bore the 4T-L432349/L432310 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 140 kN C level.", "The light L family at 158.75 mm bore (205.583×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L432349/L432310 reference at purchase.", "ABMA makes the 158.75×205.583 mm envelope interchangeable, not the ratings: NTN prints 140/247 kN for this execution and another make of the same number can differ in roller complement.", "ABMA makes the 158.75×205.583 mm envelope interchangeable, not the ratings: NTN prints 140/247 kN for this execution and another make of the same number can differ in roller complement.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 140/247 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L432349/L432310; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-L432349/L432310?", "a": "4T-L432349/L432310 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 158.75 mm bore (6.25 in), 205.583 mm outside diameter and 23.812 mm assembled width T (8.094 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 140 kN, C0 247 kN, grease limiting speed 1,500 r/min, oil speed 2,000 r/min, mass about 1890 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-L432349/L432310 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the L432349 cone or the L432310 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 140/247 kN ratings change with the cup." }, { "q": "What is the difference between 4T-L432349/L432310 and a metric ISO 355 tapered bearing?", "a": "4T-L432349/L432310 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 158.75×205.583×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-L432349/L432310 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L432349/L432310 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-L432349/L432310 list two speeds, 1,500 and 2,000 r/min?", "a": "The lower figure, 1,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L432349/L432310 at 2,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "L432349-310", "equiv_brand": "SKF", "level": "partial", "note": "Same 158.75×205.583×23.812 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-l432349-l432310", "l432349-l432310", "L432349-L432310", "4T-L432349-L432310" ], "locale_variants": {} }, { "sku": "46780-46720", "brand": "NTN", "manufacturer_designation": "NTN 4T-46780/46720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 158.75, "D_mm": 225.425, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 282, "static_load_kN": 555, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1900, "weight_g": 5190, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-46780/46720 is the NTN 4T catalogue entry for a 158.75×225.425×41.275 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 46780 identifies the cone of 158.75 mm (6.25 in) bore by catalogue lookup, and 46720 fixes the 225.425 mm OD. Selection: C 282 kN against C0 555 kN gives a C0/C ratio of 1.97 for the 158.75 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Housing fitment sequence for 4T-46780/46720: press the 46720 cup square into the 225.425 mm seat first, then bring the 46780 cone (on its 158.75 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. The rollers run with their large ends against the cone's guide rib; lubricant must reach that rib face of 4T-46780/46720, not only the raceway, or the pair smears on the first overloaded start.", "applications": [ "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 158.75 mm bore the 4T-46780/46720 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 282 kN C level.", "The pure-numeric inch family at 158.75 mm bore (225.425×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 46780/46720 reference at purchase.", "Grease packs must leave free volume inside the 41.275 mm-wide set; over-greasing a pair churning near the oil-band speed of 1,900 r/min raises temperature and destroys the setting.", "Shaft and housing fillets must clear the ring chamfers of 46780 and 46720; use undercut shoulders so the rings seat on the face, not on a radius.", "Quote the full 46780/46720 pair at ordering: the 46780 cone also ships against sibling cups, and a cup from another reference changes the 41.275 mm assembled width and the rating.", "The 282/555 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-46780/46720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-46780/46720?", "a": "4T-46780/46720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 158.75 mm bore (6.25 in), 225.425 mm outside diameter and 41.275 mm assembled width T (8.875 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 282 kN, C0 555 kN, grease limiting speed 1,400 r/min, oil speed 1,900 r/min, mass about 5190 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-46780/46720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 46780 cone or the 46720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 282/555 kN ratings change with the cup." }, { "q": "What is the difference between 4T-46780/46720 and a metric ISO 355 tapered bearing?", "a": "4T-46780/46720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 158.75×225.425×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-46780/46720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 46780/46720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-46780/46720 list two speeds, 1,400 and 1,900 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-46780/46720 at 1,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "46780", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-46780-46720", "46780-46720", "4T-46780-46720" ], "locale_variants": {} }, { "sku": "46790-46720", "brand": "NTN", "manufacturer_designation": "NTN 4T-46790/46720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 165.1, "D_mm": 225.425, "B_mm": 41.275, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 282, "static_load_kN": 555, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1900, "weight_g": 4680, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 165.1 mm carrying combined radial and thrust load, NTN lists 4T-46790/46720, a single-row 4T tapered roller set of 282 kN C and 555 kN C0 inside the 225.425 mm OD cup. Cone and cup of 4T-46790/46720 are separately stocked parts: a worn 46720 cup can be replaced against the existing 46790 cone, provided the new cup carries the identical reference — pairing across references changes the 41.275 mm assembled width and the rating. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 41.275 mm T of each 4T-46790/46720 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-46790/46720: press the 46720 cup square into the 225.425 mm seat first, then bring the 46790 cone (on its 165.1 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a m6/n6 cone seat and an easy-push cup seat are typical practice for 4T-46790/46720; reverse the fit logic when the cup rotates.", "applications": [ "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "fretting corrosion on a loose cone seat that creeps under rotating load" ], "pitfalls": [ "At 165.1 mm bore the 4T-46790/46720 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 282 kN C level.", "The pure-numeric inch family at 165.1 mm bore (225.425×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 46790/46720 reference at purchase.", "Open 4T-46790/46720 sets have no seals: a hub or gearbox needs external sealing or the 1,400 r/min grease figure is meaningless once water reaches the cone rib.", "Shaft and housing fillets must clear the ring chamfers of 46790 and 46720; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-46790/46720 near 1,400 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 282/555 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-46790/46720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-46790/46720?", "a": "4T-46790/46720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 165.1 mm bore (6.5 in), 225.425 mm outside diameter and 41.275 mm assembled width T (8.875 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 282 kN, C0 555 kN, grease limiting speed 1,400 r/min, oil speed 1,900 r/min, mass about 4680 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-46790/46720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 46790 cone or the 46720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 282/555 kN ratings change with the cup." }, { "q": "What is the difference between 4T-46790/46720 and a metric ISO 355 tapered bearing?", "a": "4T-46790/46720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 165.1×225.425×41.275 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-46790/46720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 46790/46720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-46790/46720 list two speeds, 1,400 and 1,900 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-46790/46720 at 1,900 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "46790", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-46790-46720", "46790-46720", "4T-46790-46720" ], "locale_variants": {} }, { "sku": "JHM534149-JHM534110", "brand": "NTN", "manufacturer_designation": "NTN 4T-JHM534149/JHM534110", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 170, "D_mm": 230, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 310, "static_load_kN": 520, "limiting_speed_rpm": 1400, "max_rpm": 1400, "speed_oil_rpm": 1800, "weight_g": 4370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 6.693 in (170 mm) shaft position as 4T-JHM534149/JHM534110: cone JHM534149, cup JHM534110, profiled rollers and a pressed-steel cage, rated 310 kN basic dynamic and 520 kN static. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote JHM534149/JHM534110 without it. Selection: C 310 kN against C0 520 kN gives a C0/C ratio of 1.68 for the 170 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. The printed 310/520 kN ratings belong to the assembled JHM534149+JHM534110 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 170 mm pair is misadjusted and the set will edge-load in service.", "applications": [ "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries", "mine hoist and dragline drum shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "water-induced pitting when the open bearing sees washdown without external seals" ], "pitfalls": [ "At 170 mm bore the 4T-JHM534149/JHM534110 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 310 kN C level.", "The J-prefixed JHM534149 code belongs to a metric-envelope inch family: its 170 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Grease packs must leave free volume inside the 39 mm-wide set; over-greasing a pair churning near the oil-band speed of 1,800 r/min raises temperature and destroys the setting.", "Fit selection follows the rotating ring: a rotating cone on a 170 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Inch and metric bores collide on paper — 170 mm is 6.693 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 310/520 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JHM534149/JHM534110; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JHM534149/JHM534110?", "a": "4T-JHM534149/JHM534110 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 170 mm bore (6.693 in), 230 mm outside diameter and 39 mm assembled width T (9.055 × 1.535 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 310 kN, C0 520 kN, grease limiting speed 1,400 r/min, oil speed 1,800 r/min, mass about 4370 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JHM534149/JHM534110 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JHM534149 cone or the JHM534110 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 310/520 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JHM534149/JHM534110 and a metric ISO 355 tapered bearing?", "a": "4T-JHM534149/JHM534110 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 170×230×39 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JHM534149/JHM534110 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JHM534149/JHM534110 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JHM534149/JHM534110 list two speeds, 1,400 and 1,800 r/min?", "a": "The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JHM534149/JHM534110 at 1,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JHM534149", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jhm534149-jhm534110", "4t-jhm534149-jhm534110", "jhm534149-jhm534110", "JHM534149-JHM534110", "4T-JHM534149-JHM534110" ], "locale_variants": {} }, { "sku": "36990-36920-NTN", "brand": "NTN", "manufacturer_designation": "NTN 4T-36990/36920", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 177.8, "D_mm": 227.012, "B_mm": 30.162, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 201, "static_load_kN": 415, "limiting_speed_rpm": 1300, "max_rpm": 1300, "speed_oil_rpm": 1800, "weight_g": 2910, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-36990/36920 is the NTN 4T catalogue entry for a 177.8×227.012×30.162 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-36990/36920 are separately stocked parts: a worn 36920 cup can be replaced against the existing 36990 cone, provided the new cup carries the identical reference — pairing across references changes the 30.162 mm assembled width and the rating. Grease relubrication at the 1,300 r/min limiting speed targets the cone-rib contact; sustaining 1,800 r/min needs an oil supply directed at the large roller ends. Cup-side note for 36920: within the pure-numeric inch family tables the 36990 cone is listed against several cup options, and it is the cup that fixes the 227.012 mm OD and the 30.162 mm assembled width — quote the full 36990/36920 pair, never the cone alone. With a rotating shaft a m6/n6 cone seat and an easy-push cup seat are typical practice for 4T-36990/36920; reverse the fit logic when the cup rotates.", "applications": [ "mine hoist and dragline drum shafts", "heavy press and forging-machine drive shafts", "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 177.8 mm bore the 4T-36990/36920 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 201 kN C level.", "The pure-numeric inch family at 177.8 mm bore (227.012×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 36990/36920 reference at purchase.", "Fit selection follows the rotating ring: a rotating cone on a 177.8 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "Shaft and housing fillets must clear the ring chamfers of 36990 and 36920; use undercut shoulders so the rings seat on the face, not on a radius.", "An unloaded 4T-36990/36920 near 1,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "The 201/415 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-36990/36920; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-36990/36920?", "a": "4T-36990/36920 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 177.8 mm bore (7 in), 227.012 mm outside diameter and 30.162 mm assembled width T (8.937 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 201 kN, C0 415 kN, grease limiting speed 1,300 r/min, oil speed 1,800 r/min, mass about 2910 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-36990/36920 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 36990 cone or the 36920 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 201/415 kN ratings change with the cup." }, { "q": "What is the difference between 4T-36990/36920 and a metric ISO 355 tapered bearing?", "a": "4T-36990/36920 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 177.8×227.012×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-36990/36920 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 36990/36920 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-36990/36920 list two speeds, 1,300 and 1,800 r/min?", "a": "The lower figure, 1,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-36990/36920 at 1,800 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "36990-36920", "equiv_brand": "SKF", "level": "partial", "note": "Same 177.8×227.012×30.162 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-36990-36920", "36990-36920", "4T-36990-36920", "36990-36920-NTN" ], "locale_variants": {} }, { "sku": "67790-67720", "brand": "NTN", "manufacturer_designation": "NTN 4T-67790/67720", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 177.8, "D_mm": 247.65, "B_mm": 47.625, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 380, "static_load_kN": 690, "limiting_speed_rpm": 1300, "max_rpm": 1300, "speed_oil_rpm": 1700, "weight_g": 6720, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-67790/67720 at 177.8 mm bore (7 in), 247.65 mm cup OD and 47.625 mm assembled T, with a grease limiting speed of 1,300 r/min and an oil ceiling of 1,700 r/min. Reading the designation: 4T-67790/67720 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 47.625 mm T of each 4T-67790/67720 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Housing fitment sequence for 4T-67790/67720: press the 67720 cup square into the 247.65 mm seat first, then bring the 67790 cone (on its 177.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-67790/67720 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.", "applications": [ "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cage damage from a mounting blow transmitted through the roller complement", "edge loading when shaft deflection exceeds the few arc-minutes an adjusted pair tolerates" ], "pitfalls": [ "At 177.8 mm bore the 4T-67790/67720 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 380 kN C level.", "The pure-numeric inch family at 177.8 mm bore (247.65×47.625 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 67790/67720 reference at purchase.", "Never drive the 247.65 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Grease packs must leave free volume inside the 47.625 mm-wide set; over-greasing a pair churning near the oil-band speed of 1,700 r/min raises temperature and destroys the setting.", "Inch and metric bores collide on paper — 177.8 mm is 7 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.", "The 380/690 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-67790/67720; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-67790/67720?", "a": "4T-67790/67720 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 177.8 mm bore (7 in), 247.65 mm outside diameter and 47.625 mm assembled width T (9.75 × 1.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 380 kN, C0 690 kN, grease limiting speed 1,300 r/min, oil speed 1,700 r/min, mass about 6720 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-67790/67720 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the 67790 cone or the 67720 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 380/690 kN ratings change with the cup." }, { "q": "What is the difference between 4T-67790/67720 and a metric ISO 355 tapered bearing?", "a": "4T-67790/67720 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 177.8×247.65×47.625 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-67790/67720 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 67790/67720 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-67790/67720 list two speeds, 1,300 and 1,700 r/min?", "a": "The lower figure, 1,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-67790/67720 at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "67790", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-67790-67720", "67790-67720", "4T-67790-67720" ], "locale_variants": {} }, { "sku": "JM736149-JM736110", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM736149/JM736110", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 180, "D_mm": 250, "B_mm": 47, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 410, "static_load_kN": 710, "limiting_speed_rpm": 1300, "max_rpm": 1300, "speed_oil_rpm": 1700, "weight_g": 6740, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E inch table prints 4T-JM736149/JM736110 at 180 mm bore (7.087 in), 250 mm cup OD and 47 mm assembled T, with a grease limiting speed of 1,300 r/min and an oil ceiling of 1,700 r/min. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote JM736149/JM736110 without it. Grease relubrication at the 1,300 r/min limiting speed targets the cone-rib contact; sustaining 1,700 r/min needs an oil supply directed at the large roller ends. The printed 410/710 kN ratings belong to the assembled JM736149+JM736110 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Minimum load matters at speed: an unloaded 4T-JM736149/JM736110 run near 1,300 r/min lets the rollers skid; lightly spring-preload high-speed pair arrangements.", "applications": [ "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "false brinelling on a stationary pair exposed to vibration during transport or standby", "cage damage from a mounting blow transmitted through the roller complement", "indentation of the raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "At 180 mm bore the 4T-JM736149/JM736110 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 410 kN C level.", "The J-prefixed JM736149 code belongs to a metric-envelope inch family: its 180 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Fit selection follows the rotating ring: a rotating cone on a 180 mm shaft takes a m6/n6 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.", "An unloaded 4T-JM736149/JM736110 near 1,300 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.", "Do not confuse T (47 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "The 410/710 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM736149/JM736110; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM736149/JM736110?", "a": "4T-JM736149/JM736110 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 180 mm bore (7.087 in), 250 mm outside diameter and 47 mm assembled width T (9.843 × 1.85 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 410 kN, C0 710 kN, grease limiting speed 1,300 r/min, oil speed 1,700 r/min, mass about 6740 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM736149/JM736110 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM736149 cone or the JM736110 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 410/710 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM736149/JM736110 and a metric ISO 355 tapered bearing?", "a": "4T-JM736149/JM736110 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 180×250×47 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM736149/JM736110 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM736149/JM736110 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM736149/JM736110 list two speeds, 1,300 and 1,700 r/min?", "a": "The lower figure, 1,300 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM736149/JM736110 at 1,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM736149", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm736149-jm736110", "4t-jm736149-jm736110", "jm736149-jm736110", "JM736149-JM736110", "4T-JM736149-JM736110" ], "locale_variants": {} }, { "sku": "JM738249-JM738210", "brand": "NTN", "manufacturer_designation": "NTN 4T-JM738249/JM738210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 190, "D_mm": 260, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 405, "static_load_kN": 720, "limiting_speed_rpm": 1200, "max_rpm": 1200, "speed_oil_rpm": 1600, "weight_g": 6840, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For an inch shaft of 190 mm carrying combined radial and thrust load, NTN lists 4T-JM738249/JM738210, a single-row 4T tapered roller set of 405 kN C and 720 kN C0 inside the 260 mm OD cup. Reading the designation: 4T-JM738249/JM738210 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the JM metric-envelope family lettering ties the pair to its boundary plan. Imperial cross-check for the drawing: 190×260×46 mm converts to 7.48 × 10.236 × 1.811 in; the ABMA envelope swaps with like-numbered inch parts but the 405/720 kN ratings are NTN-specific. Cup-side note for JM738210: within the JM metric-envelope family tables the JM738249 cone is listed against several cup options, and it is the cup that fixes the 260 mm OD and the 46 mm assembled width — quote the full JM738249/JM738210 pair, never the cone alone. After bedding-in, re-check the end play of the adjusted 4T-JM738249/JM738210 pair — initial seating of the ring faces relaxes the setting slightly.", "applications": [ "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts", "rolling-mill pinion stands and roll-neck auxiliaries" ], "failure_modes": [ "cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film", "false brinelling on a stationary pair exposed to vibration during transport or standby", "preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play", "cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling", "brinell marks on cone and cup raceways from impact during handling or hammer fitting" ], "pitfalls": [ "At 190 mm bore the 4T-JM738249/JM738210 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 405 kN C level.", "The J-prefixed JM738249 code belongs to a metric-envelope inch family: its 190 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.", "Quote the full JM738249/JM738210 pair at ordering: the JM738249 cone also ships against sibling cups, and a cup from another reference changes the 46 mm assembled width and the rating.", "Never drive the 260 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.", "Shaft and housing fillets must clear the ring chamfers of JM738249 and JM738210; use undercut shoulders so the rings seat on the face, not on a radius.", "The 405/720 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JM738249/JM738210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-JM738249/JM738210?", "a": "4T-JM738249/JM738210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 190 mm bore (7.48 in), 260 mm outside diameter and 46 mm assembled width T (10.236 × 1.811 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 405 kN, C0 720 kN, grease limiting speed 1,200 r/min, oil speed 1,600 r/min, mass about 6840 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-JM738249/JM738210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the JM738249 cone or the JM738210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 405/720 kN ratings change with the cup." }, { "q": "What is the difference between 4T-JM738249/JM738210 and a metric ISO 355 tapered bearing?", "a": "4T-JM738249/JM738210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 190×260×46 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-JM738249/JM738210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare JM738249/JM738210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-JM738249/JM738210 list two speeds, 1,200 and 1,600 r/min?", "a": "The lower figure, 1,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-JM738249/JM738210 at 1,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "JM738249", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "#4t-jm738249-jm738210", "4t-jm738249-jm738210", "jm738249-jm738210", "JM738249-JM738210", "4T-JM738249-JM738210" ], "locale_variants": {} }, { "sku": "LL639249-LL639210", "brand": "NTN", "manufacturer_designation": "NTN 4T-LL639249/LL639210", "series": "4t-inch-series", "type": "tapered_roller", "d_mm": 196.85, "D_mm": 241.3, "B_mm": 23.812, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 177, "static_load_kN": 330, "limiting_speed_rpm": 1200, "max_rpm": 1200, "speed_oil_rpm": 1600, "weight_g": 2070, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-LL639249/LL639210 denotes the extra-light LL family of NTN inch tapered roller bearings — cone LL639249 and cup LL639210 delivered as a matched, separable pair of 196.85 mm bore and 241.3 mm outside diameter. Reading the designation: 4T-LL639249/LL639210 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the extra-light LL family lettering ties the pair to its boundary plan. Selection: C 177 kN against C0 330 kN gives a C0/C ratio of 1.86 for the 196.85 mm bore; the pair is counted as one adjusted unit when checking L10 at the equivalent combined load. Cup-side note for LL639210: within the extra-light LL family tables the LL639249 cone is listed against several cup options, and it is the cup that fixes the 241.3 mm OD and the 23.812 mm assembled width — quote the full LL639249/LL639210 pair, never the cone alone. NTN grades inch 4T bearings as open bearings without integral seals; at 196.85 mm bore the application supplies sealing and the grease fill or oil feed.", "applications": [ "port-crane travel and hoist gearboxes", "cement-plant mill and kiln drive trains", "large shredder and recycler main shafts", "power-plant coal-mill and fan shafts" ], "failure_modes": [ "rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries", "flaking on one cone only when a bent shaft loads the O/X pair unevenly", "cup creep and housing fretting when the cup seat is cut too loose for the rotating load", "cage damage from a mounting blow transmitted through the roller complement", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "At 196.85 mm bore the 4T-LL639249/LL639210 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 177 kN C level.", "The extra-light LL family at 196.85 mm bore (241.3×23.812 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LL639249/LL639210 reference at purchase.", "Do not confuse T (23.812 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.", "Grease packs must leave free volume inside the 23.812 mm-wide set; over-greasing a pair churning near the oil-band speed of 1,600 r/min raises temperature and destroys the setting.", "Open 4T-LL639249/LL639210 sets have no seals: a hub or gearbox needs external sealing or the 1,200 r/min grease figure is meaningless once water reaches the cone rib.", "The 177/330 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LL639249/LL639210; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-LL639249/LL639210?", "a": "4T-LL639249/LL639210 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 196.85 mm bore (7.75 in), 241.3 mm outside diameter and 23.812 mm assembled width T (9.5 × 0.937 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 177 kN, C0 330 kN, grease limiting speed 1,200 r/min, oil speed 1,600 r/min, mass about 2070 g. It is an open, separable cone/cup set with a pressed-steel cage." }, { "q": "Are the cone and cup of 4T-LL639249/LL639210 interchangeable separately?", "a": "Yes — ABMA inch parts are individually interchangeable: the LL639249 cone or the LL639210 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 177/330 kN ratings change with the cup." }, { "q": "What is the difference between 4T-LL639249/LL639210 and a metric ISO 355 tapered bearing?", "a": "4T-LL639249/LL639210 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 196.85×241.3×23.812 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting." }, { "q": "What does the 4T prefix on 4T-LL639249/LL639210 mean?", "a": "4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare LL639249/LL639210 references; the 4T spelling is retained among this page's search aliases." }, { "q": "Why does 4T-LL639249/LL639210 list two speeds, 1,200 and 1,600 r/min?", "a": "The lower figure, 1,200 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-LL639249/LL639210 at 1,600 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling." } ], "cross_ref": [ { "equiv_sku": "LL639249-210", "equiv_brand": "SKF", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=193", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-ll639249-ll639210", "ll639249-ll639210", "LL639249-LL639210", "4T-LL639249-LL639210" ], "locale_variants": {} }, { "sku": "430208X", "brand": "NTN", "manufacturer_designation": "NTN 4T-430208X", "series": "4t-430-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 116, "static_load_kN": 134, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 956, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 40 mm shaft position as 4T-430208X: a factory-adjusted double-row tapered roller bearing whose two roller rows share one double cup, overall width 45 mm. Unlike a pair of single-row bearings, the TDO unit of 4T-430208X integrates both rows in one article: the 45 mm overall width and the internal clearance are ground and set by NTN, so there is no field adjustment dimension. Double-row capacity is not twice a single-row bearing: the printed 116 kN C already accounts for load sharing between the two rows of 4T-430208X, so apply it directly in the L10 calculation. Because the unit is preset, mounting 4T-430208X resembles mounting a double-row spherical or cylindrical bearing: seat the unit, clamp axially to the stated end cover torque, and verify rotation — no end-play measurement is required. Induction heating to max 120 °C is the standard fitting method at this 40 mm bore; driving the unit home through the rollers brinells both rows at once.", "applications": [ "crane travel and hoist drum shafts", "mining conveyor drive and head pulleys", "paper-machine roll and press supports", "extruder and mixer drive shafts" ], "failure_modes": [ "roller large-end smearing against the cone ribs when one row of the unit runs starved of lubricant", "preload loss and hammering noise when the cup clamping loosens and the unit gains axial float", "brinelling of both rows from a mounting blow transmitted through the roller complements", "cage damage when the unit is lifted by one cone instead of the double cup during fitting", "thermal distress when the oil supply sized for one row starves the second row" ], "pitfalls": [ "Gearbox positions of this 40 mm class rely on the preset clearance of 4T-430208X; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 430 light plan keeps 4T-430208X narrower and faster than the 432 heavy execution of the same 40 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.", "Grease packs must leave free volume across the 45 mm width; over-greasing a unit churning near the 5,500 r/min oil-band speed raises temperature and expels the grease.", "The 116 kN C already includes two-row load sharing — do not double it when pairing the unit with a floating bearing in the L10 calculation.", "The internal clearance of 4T-430208X is factory-set: no end-play adjustment exists at mounting, and any attempt to set preload with a shaft nut overloads one row.", "The 116/134 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430208X; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-430208X?", "a": "4T-430208X is a double-row tapered roller bearing of TDO (back-to-back) construction: 40 mm bore, 80 mm outside diameter and 45 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 116 kN, C0 134 kN (2203E prints a dash for Cu on this size), grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 956 g. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 40 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-430208X belongs to the light-duty 430-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-430208X be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 45 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 430208X mean?", "a": "Suffix reading on 430208X: X marks the boundary-dimension revision of the base number (D and width differ from the plain number of the same bore); suffixed variants are separate order numbers and are not interchangeable articles." }, { "q": "Why does 4T-430208X list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430208X at 5,500 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "430208X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "430208x", "4t-430208x", "430208X", "4T-430208X" ], "locale_variants": {} }, { "sku": "432208X", "brand": "NTN", "manufacturer_designation": "NTN 4T-432208X", "series": "4t-432-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 80, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 151, "static_load_kN": 187, "limiting_speed_rpm": 4100, "max_rpm": 4100, "speed_oil_rpm": 5500, "weight_g": 1180, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "NTN supplies this 40 mm shaft position as 4T-432208X: a factory-adjusted double-row tapered roller bearing whose two roller rows share one double cup, overall width 55 mm. Reading the designation: the last two digits 08 are the bore code, ×5 = 40 mm (codes 00–03 use the 10/12/15/17 exception table); the leading digits place the bearing in the heavy-duty 432-family TDO double-row series. Catalogue mass of 4T-432208X is 1.18 kg; lifting and fitting tackle must be rated for the whole preset unit, not for single-ring handling. Because the unit is preset, mounting 4T-432208X resembles mounting a double-row spherical or cylindrical bearing: seat the unit, clamp axially to the stated end cover torque, and verify rotation — no end-play measurement is required. Fillet radii and shoulder heights must follow the 2203E mounting table for 4T-432208X; the double cup must seat square across its full 55 mm width.", "applications": [ "construction-equipment swing and pivot shafts", "industrial gearbox shafts in a single locating position", "rolling-mill work-roll and backup auxiliary positions", "crane travel and hoist drum shafts" ], "failure_modes": [ "roller large-end smearing against the cone ribs when one row of the unit runs starved of lubricant", "one-row flaking when a bent shaft concentrates the combined load on a single row of the pair", "overheated running after a field attempt to \"tighten up\" the factory-set internal clearance", "cage damage when the unit is lifted by one cone instead of the double cup during fitting", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Gearbox positions of this 40 mm class rely on the preset clearance of 4T-432208X; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 432 heavy plan gives 4T-432208X its 55 mm width and 151 kN rating at the 40 mm bore; do not downgrade to a 430-family unit of the same bore without re-checking C, C0.", "An unloaded 4T-432208X near 4,100 r/min lets rollers skid; ensure a minimum load or light spring preload on high-speed positions.", "Grease packs must leave free volume across the 55 mm width; over-greasing a unit churning near the 5,500 r/min oil-band speed raises temperature and expels the grease.", "Grease packs must leave free volume across the 55 mm width; over-greasing a unit churning near the 5,500 r/min oil-band speed raises temperature and expels the grease.", "The 151/187 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-432208X; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-432208X?", "a": "4T-432208X is a double-row tapered roller bearing of TDO (back-to-back) construction: 40 mm bore, 80 mm outside diameter and 55 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 151 kN, C0 187 kN (2203E prints a dash for Cu on this size), grease limiting speed 4,100 r/min, oil speed 5,500 r/min, mass about 1.18 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 40 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-432208X belongs to the heavy-duty 432-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-432208X be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 55 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 432208X mean?", "a": "Suffix reading on 432208X: X marks the boundary-dimension revision of the base number (D and width differ from the plain number of the same bore); suffixed variants are separate order numbers and are not interchangeable articles." }, { "q": "Why does 4T-432208X list two speeds, 4,100 and 5,500 r/min?", "a": "The lower figure, 4,100 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-432208X at 5,500 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "432208X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "432208x", "4t-432208x", "432208X", "4T-432208X" ], "locale_variants": {} }, { "sku": "430308", "brand": "NTN", "manufacturer_designation": "NTN 4T-430308", "series": "4t-430-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 90, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 174, "static_load_kN": 204, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 1700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For a 40 mm shaft needing a compact two-direction thrust location, NTN lists 4T-430308, a TDO double-row 4T unit of 174 kN C and 204 kN C0 in the light-duty 430-family TDO double-row series. Unlike a pair of single-row bearings, the TDO unit of 4T-430308 integrates both rows in one article: the 56 mm overall width and the internal clearance are ground and set by NTN, so there is no field adjustment dimension. Grease relubrication at the 3,700 r/min limiting speed must reach both roller rows; sustaining 4,900 r/min needs an oil supply with defined flow through the double cup. The internal clearance of 4T-430308 is set at the factory by the double cup and spacer-less grinding; do not attempt to re-adjust it with shaft nuts — the 56 mm overall width is the finished dimension. The preset clearance suits the standard temperature range; unusual thermal gradients between shaft and housing call for a clearance review against the 40 mm size before ordering 4T-430308.", "applications": [ "paper-machine roll and press supports", "extruder and mixer drive shafts", "construction-equipment swing and pivot shafts", "industrial gearbox shafts in a single locating position" ], "failure_modes": [ "edge loading on one row when the housing seats the double cup cocked across its width", "preload loss and hammering noise when the cup clamping loosens and the unit gains axial float", "brinelling of both rows from a mounting blow transmitted through the roller complements", "cage damage when the unit is lifted by one cone instead of the double cup during fitting", "indentation of both raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Gearbox positions of this 40 mm class rely on the preset clearance of 4T-430308; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 430 light plan keeps 4T-430308 narrower and faster than the 432 heavy execution of the same 40 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.", "Order by the full 430308 code including suffixes — U, X, DX, E1 and UTG variants share the 40 mm bore but are different articles with different internal geometry.", "Lubricant must reach both rows: a housing groove aligned to the cup mid-width of 4T-430308 feeds the two roller complements evenly; a single-side feed starves the far row.", "The 174 kN C already includes two-row load sharing — do not double it when pairing the unit with a floating bearing in the L10 calculation.", "The 174/204 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430308; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-430308?", "a": "4T-430308 is a double-row tapered roller bearing of TDO (back-to-back) construction: 40 mm bore, 90 mm outside diameter and 56 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 174 kN, C0 204 kN (2203E prints a dash for Cu on this size), grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 1.7 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 40 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-430308 belongs to the light-duty 430-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-430308 be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 56 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 430308 mean?", "a": "With no letter suffix, 430308 is the basic open double-row execution: steel cages, factory-set internal clearance, no feature suffix in the order code." }, { "q": "Why does 4T-430308 list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430308 at 4,900 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "430308", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-430308", "430308", "4T-430308" ], "locale_variants": {} }, { "sku": "430308DX", "brand": "NTN", "manufacturer_designation": "NTN 4T-430308DX", "series": "4t-430-series", "type": "tapered_roller", "d_mm": 40, "D_mm": 90, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 147, "static_load_kN": 171, "limiting_speed_rpm": 3200, "max_rpm": 3200, "speed_oil_rpm": 4200, "weight_g": 1590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For a 40 mm shaft needing a compact two-direction thrust location, NTN lists 4T-430308DX, a TDO double-row 4T unit of 147 kN C and 171 kN C0 in the light-duty 430-family TDO double-row series. Unlike a pair of single-row bearings, the TDO unit of 4T-430308DX integrates both rows in one article: the 56 mm overall width and the internal clearance are ground and set by NTN, so there is no field adjustment dimension. The 25.0 mm radial section over the 40 mm bore carries two roller rows across the 56 mm width; abutment shoulders must clear both cone bores and the double-cup OD. TDO construction means the two cone assemblies of 4T-430308DX face away from each other inside one double cup: the load lines diverge outward, giving a wide effective spread and high moment stiffness for the 40 mm shaft. Do not separate the cones from the double cup at inspection unless re-matching is guaranteed — the rows of 4T-430308DX are ground as a unit.", "applications": [ "extruder and mixer drive shafts", "construction-equipment swing and pivot shafts", "industrial gearbox shafts in a single locating position", "rolling-mill work-roll and backup auxiliary positions" ], "failure_modes": [ "roller large-end smearing against the cone ribs when one row of the unit runs starved of lubricant", "preload loss and hammering noise when the cup clamping loosens and the unit gains axial float", "brinelling of both rows from a mounting blow transmitted through the roller complements", "pressed-steel cage pocket wear from roller skid at light load and high speed", "water-induced pitting when washdown reaches the open unit without external seals" ], "pitfalls": [ "Gearbox positions of this 40 mm class rely on the preset clearance of 4T-430308DX; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 430 light plan keeps 4T-430308DX narrower and faster than the 432 heavy execution of the same 40 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.", "The 147 kN C already includes two-row load sharing — do not double it when pairing the unit with a floating bearing in the L10 calculation.", "The 25.0 mm section leaves little room for oversized shaft fillets; follow the 2203E chamfer table for 4T-430308DX or the cones bottom out on the radius.", "Order by the full 430308DX code including suffixes — U, X, DX, E1 and UTG variants share the 40 mm bore but are different articles with different internal geometry.", "The 147/171 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430308DX; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-430308DX?", "a": "4T-430308DX is a double-row tapered roller bearing of TDO (back-to-back) construction: 40 mm bore, 90 mm outside diameter and 56 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 147 kN, C0 171 kN (2203E prints a dash for Cu on this size), grease limiting speed 3,200 r/min, oil speed 4,200 r/min, mass about 1.59 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 40 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-430308DX belongs to the light-duty 430-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-430308DX be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 56 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 430308DX mean?", "a": "Suffix reading on 430308DX: X marks the boundary-dimension revision of the base number (D and width differ from the plain number of the same bore); suffixed variants are separate order numbers and are not interchangeable articles." }, { "q": "Why does 4T-430308DX list two speeds, 3,200 and 4,200 r/min?", "a": "The lower figure, 3,200 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430308DX at 4,200 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "430308DX", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "430308dx", "4t-430308dx", "430308DX", "4T-430308DX" ], "locale_variants": {} }, { "sku": "430209", "brand": "NTN", "manufacturer_designation": "NTN 4T-430209", "series": "4t-430-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 85, "B_mm": 47, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 129, "static_load_kN": 157, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 1080, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E double-row table prints 4T-430209 at 45 mm bore, 85 mm OD and 47 mm overall width, with a grease limiting speed of 3,700 r/min and an oil ceiling of 4,900 r/min. Large sizes continue the plans under different leading digits: 4130/4131 and 4230/4231 belong to the 430-family dimension plan, while 3230/3231 continue the 432 heavy plan — 430209 reads accordingly. 2203E prints no Cu fatigue load limit for 4T-430209 (the dash in the Cu column); life work for this size uses the 129/157 kN C/C0 pair directly. The internal clearance of 4T-430209 is set at the factory by the double cup and spacer-less grinding; do not attempt to re-adjust it with shaft nuts — the 47 mm overall width is the finished dimension. With a rotating shaft a k5/m5 seat on the 45 mm journal and a located cup in the housing are typical practice for 4T-430209.", "applications": [ "industrial gearbox shafts in a single locating position", "rolling-mill work-roll and backup auxiliary positions", "crane travel and hoist drum shafts", "mining conveyor drive and head pulleys" ], "failure_modes": [ "edge loading on one row when the housing seats the double cup cocked across its width", "preload loss and hammering noise when the cup clamping loosens and the unit gains axial float", "brinelling of both rows from a mounting blow transmitted through the roller complements", "cage damage when the unit is lifted by one cone instead of the double cup during fitting", "indentation of both raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Gearbox positions of this 45 mm class rely on the preset clearance of 4T-430209; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 430 light plan keeps 4T-430209 narrower and faster than the 432 heavy execution of the same 45 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.", "Lubricant must reach both rows: a housing groove aligned to the cup mid-width of 4T-430209 feeds the two roller complements evenly; a single-side feed starves the far row.", "Lubricant must reach both rows: a housing groove aligned to the cup mid-width of 4T-430209 feeds the two roller complements evenly; a single-side feed starves the far row.", "Never interchange a TDO double-row unit with two single-row bearings of similar size: the 47 mm width, load spread and clearance logic of 4T-430209 are unit-specific.", "The 129/157 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430209; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-430209?", "a": "4T-430209 is a double-row tapered roller bearing of TDO (back-to-back) construction: 45 mm bore, 85 mm outside diameter and 47 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 129 kN, C0 157 kN (2203E prints a dash for Cu on this size), grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 1.08 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 45 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-430209 belongs to the light-duty 430-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-430209 be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 47 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 430209 mean?", "a": "With no letter suffix, 430209 is the basic open double-row execution: steel cages, factory-set internal clearance, no feature suffix in the order code." }, { "q": "Why does 4T-430209 list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430209 at 4,900 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "430209", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-430209", "430209", "4T-430209" ], "locale_variants": {} }, { "sku": "432209", "brand": "NTN", "manufacturer_designation": "NTN 4T-432209", "series": "4t-432-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 85, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 156, "static_load_kN": 200, "limiting_speed_rpm": 3700, "max_rpm": 3700, "speed_oil_rpm": 4900, "weight_g": 1270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-432209 is an NTN double-row tapered roller bearing of TDO (back-to-back) construction: two cone assemblies against one double cup, supplied as a preset unit of 45×85×55 mm. The 4T- prefix is NTN's tapered roller quality mark; 430 numbers the light TDO plan and 432 the heavy TDO plan — at the same 45 mm bore the 432 execution carries a wider, heavier section than the 430. Double-row capacity is not twice a single-row bearing: the printed 156 kN C already accounts for load sharing between the two rows of 4T-432209, so apply it directly in the L10 calculation. TDO construction means the two cone assemblies of 4T-432209 face away from each other inside one double cup: the load lines diverge outward, giving a wide effective spread and high moment stiffness for the 45 mm shaft. Axial clamping of the double cup must be uniform around the 85 mm OD; a cocked end cover pinches one row and destroys the factory clearance setting.", "applications": [ "construction-equipment swing and pivot shafts", "industrial gearbox shafts in a single locating position", "rolling-mill work-roll and backup auxiliary positions", "crane travel and hoist drum shafts" ], "failure_modes": [ "edge loading on one row when the housing seats the double cup cocked across its width", "preload loss and hammering noise when the cup clamping loosens and the unit gains axial float", "brinelling of both rows from a mounting blow transmitted through the roller complements", "pressed-steel cage pocket wear from roller skid at light load and high speed", "water-induced pitting when washdown reaches the open unit without external seals" ], "pitfalls": [ "Gearbox positions of this 45 mm class rely on the preset clearance of 4T-432209; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 432 heavy plan gives 4T-432209 its 55 mm width and 156 kN rating at the 45 mm bore; do not downgrade to a 430-family unit of the same bore without re-checking C, C0.", "Clamping the double cup with a cocked end cover pinches one row: tighten the 85 mm OD clamping uniformly around the circumference.", "Grease packs must leave free volume across the 55 mm width; over-greasing a unit churning near the 4,900 r/min oil-band speed raises temperature and expels the grease.", "Never interchange a TDO double-row unit with two single-row bearings of similar size: the 55 mm width, load spread and clearance logic of 4T-432209 are unit-specific.", "The 156/200 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-432209; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-432209?", "a": "4T-432209 is a double-row tapered roller bearing of TDO (back-to-back) construction: 45 mm bore, 85 mm outside diameter and 55 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 156 kN, C0 200 kN (2203E prints a dash for Cu on this size), grease limiting speed 3,700 r/min, oil speed 4,900 r/min, mass about 1.27 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 45 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-432209 belongs to the heavy-duty 432-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-432209 be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 55 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 432209 mean?", "a": "With no letter suffix, 432209 is the basic open double-row execution: steel cages, factory-set internal clearance, no feature suffix in the order code." }, { "q": "Why does 4T-432209 list two speeds, 3,700 and 4,900 r/min?", "a": "The lower figure, 3,700 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-432209 at 4,900 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "432209", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-432209", "432209", "4T-432209" ], "locale_variants": {} }, { "sku": "430309", "brand": "NTN", "manufacturer_designation": "NTN 4T-430309", "series": "4t-430-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 100, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 212, "static_load_kN": 251, "limiting_speed_rpm": 3300, "max_rpm": 3300, "speed_oil_rpm": 4400, "weight_g": 2170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-430309 belongs to the light-duty 430-family TDO double-row series of NTN double-row tapered roller bearings; the unit is mounted as one article and its internal clearance is set at the factory, not on the shaft. With no letter suffix, 430309 is the basic open double-row execution: steel cages, factory-set internal clearance, no feature suffix in the order code. The 4.7 kN of dynamic capacity per millimetre of bore summarises the 212 kN rating over the 45 mm bore — compare substitution candidates on this ratio and on the 60 mm width. The internal clearance of 4T-430309 is set at the factory by the double cup and spacer-less grinding; do not attempt to re-adjust it with shaft nuts — the 60 mm overall width is the finished dimension. Re-lubrication holes and grooves of the housing should line up with the cup's mid-width so fresh grease reaches both roller rows of 4T-430309.", "applications": [ "construction-equipment swing and pivot shafts", "industrial gearbox shafts in a single locating position", "rolling-mill work-roll and backup auxiliary positions", "crane travel and hoist drum shafts" ], "failure_modes": [ "roller large-end smearing against the cone ribs when one row of the unit runs starved of lubricant", "one-row flaking when a bent shaft concentrates the combined load on a single row of the pair", "overheated running after a field attempt to \"tighten up\" the factory-set internal clearance", "pressed-steel cage pocket wear from roller skid at light load and high speed", "indentation of both raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Gearbox positions of this 45 mm class rely on the preset clearance of 4T-430309; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 430 light plan keeps 4T-430309 narrower and faster than the 432 heavy execution of the same 45 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.", "Open 4T-430309 units have no seals: the housing must seal both rows or the 3,300 r/min grease figure is meaningless once contamination enters.", "The 212 kN C already includes two-row load sharing — do not double it when pairing the unit with a floating bearing in the L10 calculation.", "Order by the full 430309 code including suffixes — U, X, DX, E1 and UTG variants share the 45 mm bore but are different articles with different internal geometry.", "The 212/251 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430309; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-430309?", "a": "4T-430309 is a double-row tapered roller bearing of TDO (back-to-back) construction: 45 mm bore, 100 mm outside diameter and 60 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 212 kN, C0 251 kN (2203E prints a dash for Cu on this size), grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 2.17 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 45 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-430309 belongs to the light-duty 430-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-430309 be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 60 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 430309 mean?", "a": "With no letter suffix, 430309 is the basic open double-row execution: steel cages, factory-set internal clearance, no feature suffix in the order code." }, { "q": "Why does 4T-430309 list two speeds, 3,300 and 4,400 r/min?", "a": "The lower figure, 3,300 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430309 at 4,400 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "430309", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-430309", "430309", "4T-430309" ], "locale_variants": {} }, { "sku": "430309DX", "brand": "NTN", "manufacturer_designation": "NTN 4T-430309DX", "series": "4t-430-series", "type": "tapered_roller", "d_mm": 45, "D_mm": 100, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 183, "static_load_kN": 218, "limiting_speed_rpm": 2800, "max_rpm": 2800, "speed_oil_rpm": 3800, "weight_g": 2110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-430309DX is an NTN double-row tapered roller bearing of TDO (back-to-back) construction: two cone assemblies against one double cup, supplied as a preset unit of 45×100×60 mm. Large sizes continue the plans under different leading digits: 4130/4131 and 4230/4231 belong to the 430-family dimension plan, while 3230/3231 continue the 432 heavy plan — 430309DX reads accordingly. Catalogue mass of 4T-430309DX is 2.11 kg; lifting and fitting tackle must be rated for the whole preset unit, not for single-ring handling. The internal clearance of 4T-430309DX is set at the factory by the double cup and spacer-less grinding; do not attempt to re-adjust it with shaft nuts — the 60 mm overall width is the finished dimension. At 183 kN C the unit offers about 4.1 kN per millimetre of the 45 mm bore — heavy-section TDO rows of this class run warm, so confirm oil availability before working near 3,800 r/min.", "applications": [ "crane travel and hoist drum shafts", "mining conveyor drive and head pulleys", "paper-machine roll and press supports", "extruder and mixer drive shafts" ], "failure_modes": [ "roller large-end smearing against the cone ribs when one row of the unit runs starved of lubricant", "one-row flaking when a bent shaft concentrates the combined load on a single row of the pair", "overheated running after a field attempt to \"tighten up\" the factory-set internal clearance", "cage damage when the unit is lifted by one cone instead of the double cup during fitting", "indentation of both raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Gearbox positions of this 45 mm class rely on the preset clearance of 4T-430309DX; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 430 light plan keeps 4T-430309DX narrower and faster than the 432 heavy execution of the same 45 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.", "Grease packs must leave free volume across the 60 mm width; over-greasing a unit churning near the 3,800 r/min oil-band speed raises temperature and expels the grease.", "Grease packs must leave free volume across the 60 mm width; over-greasing a unit churning near the 3,800 r/min oil-band speed raises temperature and expels the grease.", "Clamping the double cup with a cocked end cover pinches one row: tighten the 100 mm OD clamping uniformly around the circumference.", "The 183/218 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430309DX; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-430309DX?", "a": "4T-430309DX is a double-row tapered roller bearing of TDO (back-to-back) construction: 45 mm bore, 100 mm outside diameter and 60 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 183 kN, C0 218 kN (2203E prints a dash for Cu on this size), grease limiting speed 2,800 r/min, oil speed 3,800 r/min, mass about 2.11 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 45 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-430309DX belongs to the light-duty 430-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-430309DX be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 60 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 430309DX mean?", "a": "Suffix reading on 430309DX: X marks the boundary-dimension revision of the base number (D and width differ from the plain number of the same bore); suffixed variants are separate order numbers and are not interchangeable articles." }, { "q": "Why does 4T-430309DX list two speeds, 2,800 and 3,800 r/min?", "a": "The lower figure, 2,800 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430309DX at 3,800 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "430309DX", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "430309dx", "4t-430309dx", "430309DX", "4T-430309DX" ], "locale_variants": {} }, { "sku": "430210", "brand": "NTN", "manufacturer_designation": "NTN 4T-430210", "series": "4t-430-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 90, "B_mm": 49, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 147, "static_load_kN": 186, "limiting_speed_rpm": 3400, "max_rpm": 3400, "speed_oil_rpm": 4500, "weight_g": 1230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For a 50 mm shaft needing a compact two-direction thrust location, NTN lists 4T-430210, a TDO double-row 4T unit of 147 kN C and 186 kN C0 in the light-duty 430-family TDO double-row series. Unlike a pair of single-row bearings, the TDO unit of 4T-430210 integrates both rows in one article: the 49 mm overall width and the internal clearance are ground and set by NTN, so there is no field adjustment dimension. Speed planning uses both catalogue columns: grease 3,400 r/min is the mechanical ceiling, oil 4,500 r/min with oil lubrication — a 1,100 r/min margin at this size. The internal clearance of 4T-430210 is set at the factory by the double cup and spacer-less grinding; do not attempt to re-adjust it with shaft nuts — the 49 mm overall width is the finished dimension. The preset clearance suits the standard temperature range; unusual thermal gradients between shaft and housing call for a clearance review against the 50 mm size before ordering 4T-430210.", "applications": [ "paper-machine roll and press supports", "extruder and mixer drive shafts", "construction-equipment swing and pivot shafts", "industrial gearbox shafts in a single locating position" ], "failure_modes": [ "edge loading on one row when the housing seats the double cup cocked across its width", "brinelling of both rows from a mounting blow transmitted through the roller complements", "preload loss and hammering noise when the cup clamping loosens and the unit gains axial float", "pressed-steel cage pocket wear from roller skid at light load and high speed", "indentation of both raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Gearbox positions of this 50 mm class rely on the preset clearance of 4T-430210; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 430 light plan keeps 4T-430210 narrower and faster than the 432 heavy execution of the same 50 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.", "The 147 kN C already includes two-row load sharing — do not double it when pairing the unit with a floating bearing in the L10 calculation.", "The 147 kN C already includes two-row load sharing — do not double it when pairing the unit with a floating bearing in the L10 calculation.", "The 20.0 mm section leaves little room for oversized shaft fillets; follow the 2203E chamfer table for 4T-430210 or the cones bottom out on the radius.", "The 147/186 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430210; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-430210?", "a": "4T-430210 is a double-row tapered roller bearing of TDO (back-to-back) construction: 50 mm bore, 90 mm outside diameter and 49 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 147 kN, C0 186 kN (2203E prints a dash for Cu on this size), grease limiting speed 3,400 r/min, oil speed 4,500 r/min, mass about 1.23 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 50 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-430210 belongs to the light-duty 430-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-430210 be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 49 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 430210 mean?", "a": "With no letter suffix, 430210 is the basic open double-row execution: steel cages, factory-set internal clearance, no feature suffix in the order code." }, { "q": "Why does 4T-430210 list two speeds, 3,400 and 4,500 r/min?", "a": "The lower figure, 3,400 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430210 at 4,500 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "430210", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-430210", "430210", "4T-430210" ], "locale_variants": {} }, { "sku": "432210U", "brand": "NTN", "manufacturer_designation": "NTN 4T-432210U", "series": "4t-432-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 90, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 166, "static_load_kN": 218, "fatigue_load_limit_kN": 26.6, "limiting_speed_rpm": 3400, "max_rpm": 3400, "speed_oil_rpm": 4500, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "For a 50 mm shaft needing a compact two-direction thrust location, NTN lists 4T-432210U, a TDO double-row 4T unit of 166 kN C and 218 kN C0 in the heavy-duty 432-family TDO double-row series. Reading the designation: the last two digits 10 are the bore code, ×5 = 50 mm (codes 00–03 use the 10/12/15/17 exception table); the leading digits place the bearing in the heavy-duty 432-family TDO double-row series. The 3.3 kN of dynamic capacity per millimetre of bore summarises the 166 kN rating over the 50 mm bore — compare substitution candidates on this ratio and on the 55 mm width. TDO construction means the two cone assemblies of 4T-432210U face away from each other inside one double cup: the load lines diverge outward, giving a wide effective spread and high moment stiffness for the 50 mm shaft. Induction heating to max 120 °C is the standard fitting method at this 50 mm bore; driving the unit home through the rollers brinells both rows at once.", "applications": [ "paper-machine roll and press supports", "extruder and mixer drive shafts", "construction-equipment swing and pivot shafts", "industrial gearbox shafts in a single locating position" ], "failure_modes": [ "roller large-end smearing against the cone ribs when one row of the unit runs starved of lubricant", "overheated running after a field attempt to \"tighten up\" the factory-set internal clearance", "one-row flaking when a bent shaft concentrates the combined load on a single row of the pair", "cage damage when the unit is lifted by one cone instead of the double cup during fitting", "water-induced pitting when washdown reaches the open unit without external seals" ], "pitfalls": [ "Gearbox positions of this 50 mm class rely on the preset clearance of 4T-432210U; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 432 heavy plan gives 4T-432210U its 55 mm width and 166 kN rating at the 50 mm bore; do not downgrade to a 430-family unit of the same bore without re-checking C, C0 and the 26.6 kN Cu.", "Lubricant must reach both rows: a housing groove aligned to the cup mid-width of 4T-432210U feeds the two roller complements evenly; a single-side feed starves the far row.", "Clamping the double cup with a cocked end cover pinches one row: tighten the 90 mm OD clamping uniformly around the circumference.", "Open 4T-432210U units have no seals: the housing must seal both rows or the 3,400 r/min grease figure is meaningless once contamination enters.", "The 166/218 kN ratings and 26.6 kN Cu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-432210U; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-432210U?", "a": "4T-432210U is a double-row tapered roller bearing of TDO (back-to-back) construction: 50 mm bore, 90 mm outside diameter and 55 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 166 kN, C0 218 kN, Cu 26.6 kN, grease limiting speed 3,400 r/min, oil speed 4,500 r/min, mass about 1.4 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 50 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-432210U belongs to the heavy-duty 432-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-432210U be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 55 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 432210U mean?", "a": "Suffix reading on 432210U: U marks the uprated/reinforced internal design, a separate order number with higher capacity than the basic execution; suffixed variants are separate order numbers and are not interchangeable articles." }, { "q": "Why does 4T-432210U list two speeds, 3,400 and 4,500 r/min?", "a": "The lower figure, 3,400 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-432210U at 4,500 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "432210U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "432210u", "4t-432210u", "432210U", "4T-432210U" ], "locale_variants": {} }, { "sku": "430310", "brand": "NTN", "manufacturer_designation": "NTN 4T-430310", "series": "4t-430-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 110, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 252, "static_load_kN": 305, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 2810, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-430310 is an NTN double-row tapered roller bearing of TDO (back-to-back) construction: two cone assemblies against one double cup, supplied as a preset unit of 50×110×64 mm. Large sizes continue the plans under different leading digits: 4130/4131 and 4230/4231 belong to the 430-family dimension plan, while 3230/3231 continue the 432 heavy plan — 430310 reads accordingly. Catalogue mass of 4T-430310 is 2.81 kg; lifting and fitting tackle must be rated for the whole preset unit, not for single-ring handling. The internal clearance of 4T-430310 is set at the factory by the double cup and spacer-less grinding; do not attempt to re-adjust it with shaft nuts — the 64 mm overall width is the finished dimension. The open unit carries no seals; the housing of 4T-430310 must provide sealing and the grease fill or oil feed to both rows.", "applications": [ "crane travel and hoist drum shafts", "mining conveyor drive and head pulleys", "paper-machine roll and press supports", "extruder and mixer drive shafts" ], "failure_modes": [ "edge loading on one row when the housing seats the double cup cocked across its width", "overheated running after a field attempt to \"tighten up\" the factory-set internal clearance", "one-row flaking when a bent shaft concentrates the combined load on a single row of the pair", "cage fatigue after continuous running near the grease limiting speed without oil cooling", "indentation of both raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Gearbox positions of this 50 mm class rely on the preset clearance of 4T-430310; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 430 light plan keeps 4T-430310 narrower and faster than the 432 heavy execution of the same 50 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.", "Grease packs must leave free volume across the 64 mm width; over-greasing a unit churning near the 4,000 r/min oil-band speed raises temperature and expels the grease.", "Clamping the double cup with a cocked end cover pinches one row: tighten the 110 mm OD clamping uniformly around the circumference.", "At inspection do not mix the cone assemblies of 4T-430310 with another unit; rows are ground together and re-matching is not guaranteed in the field.", "The 252/305 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430310; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-430310?", "a": "4T-430310 is a double-row tapered roller bearing of TDO (back-to-back) construction: 50 mm bore, 110 mm outside diameter and 64 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 252 kN, C0 305 kN (2203E prints a dash for Cu on this size), grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 2.81 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 50 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-430310 belongs to the light-duty 430-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-430310 be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 64 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 430310 mean?", "a": "With no letter suffix, 430310 is the basic open double-row execution: steel cages, factory-set internal clearance, no feature suffix in the order code." }, { "q": "Why does 4T-430310 list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430310 at 4,000 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "430310", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "4t-430310", "430310", "4T-430310" ], "locale_variants": {} }, { "sku": "430310DX", "brand": "NTN", "manufacturer_designation": "NTN 4T-430310DX", "series": "4t-430-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 110, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 216, "static_load_kN": 260, "limiting_speed_rpm": 2600, "max_rpm": 2600, "speed_oil_rpm": 3500, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-430310DX belongs to the light-duty 430-family TDO double-row series of NTN double-row tapered roller bearings; the unit is mounted as one article and its internal clearance is set at the factory, not on the shaft. Unlike a pair of single-row bearings, the TDO unit of 4T-430310DX integrates both rows in one article: the 64 mm overall width and the internal clearance are ground and set by NTN, so there is no field adjustment dimension. Axial capacity is bidirectional because the rows are opposed: 4T-430310DX locates the shaft in both directions with C0 260 kN behind the static check of the more heavily loaded row. The internal clearance of 4T-430310DX is set at the factory by the double cup and spacer-less grinding; do not attempt to re-adjust it with shaft nuts — the 64 mm overall width is the finished dimension. Fillet radii and shoulder heights must follow the 2203E mounting table for 4T-430310DX; the double cup must seat square across its full 64 mm width.", "applications": [ "paper-machine roll and press supports", "extruder and mixer drive shafts", "construction-equipment swing and pivot shafts", "industrial gearbox shafts in a single locating position" ], "failure_modes": [ "edge loading on one row when the housing seats the double cup cocked across its width", "one-row flaking when a bent shaft concentrates the combined load on a single row of the pair", "overheated running after a field attempt to \"tighten up\" the factory-set internal clearance", "cage fatigue after continuous running near the grease limiting speed without oil cooling", "indentation of both raceways by hard particles in an open, unsealed arrangement" ], "pitfalls": [ "Gearbox positions of this 50 mm class rely on the preset clearance of 4T-430310DX; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 430 light plan keeps 4T-430310DX narrower and faster than the 432 heavy execution of the same 50 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.", "Never interchange a TDO double-row unit with two single-row bearings of similar size: the 64 mm width, load spread and clearance logic of 4T-430310DX are unit-specific.", "The 216 kN C already includes two-row load sharing — do not double it when pairing the unit with a floating bearing in the L10 calculation.", "Clamping the double cup with a cocked end cover pinches one row: tighten the 110 mm OD clamping uniformly around the circumference.", "The 216/260 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430310DX; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-430310DX?", "a": "4T-430310DX is a double-row tapered roller bearing of TDO (back-to-back) construction: 50 mm bore, 110 mm outside diameter and 64 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 216 kN, C0 260 kN (2203E prints a dash for Cu on this size), grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 2.7 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 50 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-430310DX belongs to the light-duty 430-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-430310DX be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 64 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 430310DX mean?", "a": "Suffix reading on 430310DX: X marks the boundary-dimension revision of the base number (D and width differ from the plain number of the same bore); suffixed variants are separate order numbers and are not interchangeable articles." }, { "q": "Why does 4T-430310DX list two speeds, 2,600 and 3,500 r/min?", "a": "The lower figure, 2,600 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430310DX at 3,500 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "430310DX", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "430310dx", "4t-430310dx", "430310DX", "4T-430310DX" ], "locale_variants": {} }, { "sku": "432310U", "brand": "NTN", "manufacturer_designation": "NTN 4T-432310U", "series": "4t-432-series", "type": "tapered_roller", "d_mm": 50, "D_mm": 110, "B_mm": 90, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 350, "static_load_kN": 465, "fatigue_load_limit_kN": 56.5, "limiting_speed_rpm": 3000, "max_rpm": 3000, "speed_oil_rpm": 4000, "weight_g": 3980, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-432310U is the NTN 4T catalogue entry for a 50×110×90 mm double-row tapered roller bearing — the TDO arrangement reacts radial load plus thrust in both directions without a second bearing. Large sizes continue the plans under different leading digits: 4130/4131 and 4230/4231 belong to the 430-family dimension plan, while 3230/3231 continue the 432 heavy plan — 432310U reads accordingly. Axial capacity is bidirectional because the rows are opposed: 4T-432310U locates the shaft in both directions with C0 465 kN behind the static check of the more heavily loaded row. Because the unit is preset, mounting 4T-432310U resembles mounting a double-row spherical or cylindrical bearing: seat the unit, clamp axially to the stated end cover torque, and verify rotation — no end-play measurement is required. Fillet radii and shoulder heights must follow the 2203E mounting table for 4T-432310U; the double cup must seat square across its full 90 mm width.", "applications": [ "paper-machine roll and press supports", "extruder and mixer drive shafts", "construction-equipment swing and pivot shafts", "industrial gearbox shafts in a single locating position" ], "failure_modes": [ "edge loading on one row when the housing seats the double cup cocked across its width", "overheated running after a field attempt to \"tighten up\" the factory-set internal clearance", "one-row flaking when a bent shaft concentrates the combined load on a single row of the pair", "cage damage when the unit is lifted by one cone instead of the double cup during fitting", "rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load" ], "pitfalls": [ "Gearbox positions of this 50 mm class rely on the preset clearance of 4T-432310U; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 432 heavy plan gives 4T-432310U its 90 mm width and 350 kN rating at the 50 mm bore; do not downgrade to a 430-family unit of the same bore without re-checking C, C0 and the 56.5 kN Cu.", "The 350 kN C already includes two-row load sharing — do not double it when pairing the unit with a floating bearing in the L10 calculation.", "Open 4T-432310U units have no seals: the housing must seal both rows or the 3,000 r/min grease figure is meaningless once contamination enters.", "The internal clearance of 4T-432310U is factory-set: no end-play adjustment exists at mounting, and any attempt to set preload with a shaft nut overloads one row.", "The 350/465 kN ratings and 56.5 kN Cu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-432310U; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-432310U?", "a": "4T-432310U is a double-row tapered roller bearing of TDO (back-to-back) construction: 50 mm bore, 110 mm outside diameter and 90 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 350 kN, C0 465 kN, Cu 56.5 kN, grease limiting speed 3,000 r/min, oil speed 4,000 r/min, mass about 3.98 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 50 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-432310U belongs to the heavy-duty 432-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-432310U be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 90 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 432310U mean?", "a": "Suffix reading on 432310U: U marks the uprated/reinforced internal design, a separate order number with higher capacity than the basic execution; suffixed variants are separate order numbers and are not interchangeable articles." }, { "q": "Why does 4T-432310U list two speeds, 3,000 and 4,000 r/min?", "a": "The lower figure, 3,000 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-432310U at 4,000 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "432310U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "432310u", "4t-432310u", "432310U", "4T-432310U" ], "locale_variants": {} }, { "sku": "430211X", "brand": "NTN", "manufacturer_designation": "NTN 4T-430211X", "series": "4t-430-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 100, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 177, "static_load_kN": 221, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 1570, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "The NTN 2203E double-row table prints 4T-430211X at 55 mm bore, 100 mm OD and 51 mm overall width, with a grease limiting speed of 3,100 r/min and an oil ceiling of 4,100 r/min. The 4T- prefix is NTN's tapered roller quality mark; 430 numbers the light TDO plan and 432 the heavy TDO plan — at the same 55 mm bore the 432 execution carries a wider, heavier section than the 430. Selection: C 177 kN against C0 221 kN gives a C0/C ratio of 1.25; the two rows of 4T-430211X share the combined load as one bearing position. TDO construction means the two cone assemblies of 4T-430211X face away from each other inside one double cup: the load lines diverge outward, giving a wide effective spread and high moment stiffness for the 55 mm shaft. Re-lubrication holes and grooves of the housing should line up with the cup's mid-width so fresh grease reaches both roller rows of 4T-430211X.", "applications": [ "construction-equipment swing and pivot shafts", "industrial gearbox shafts in a single locating position", "rolling-mill work-roll and backup auxiliary positions", "crane travel and hoist drum shafts" ], "failure_modes": [ "edge loading on one row when the housing seats the double cup cocked across its width", "preload loss and hammering noise when the cup clamping loosens and the unit gains axial float", "brinelling of both rows from a mounting blow transmitted through the roller complements", "pressed-steel cage pocket wear from roller skid at light load and high speed", "false brinelling on a stored or standby unit exposed to vibration" ], "pitfalls": [ "Gearbox positions of this 55 mm class rely on the preset clearance of 4T-430211X; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 430 light plan keeps 4T-430211X narrower and faster than the 432 heavy execution of the same 55 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.", "Open 4T-430211X units have no seals: the housing must seal both rows or the 3,100 r/min grease figure is meaningless once contamination enters.", "Open 4T-430211X units have no seals: the housing must seal both rows or the 3,100 r/min grease figure is meaningless once contamination enters.", "Clamping the double cup with a cocked end cover pinches one row: tighten the 100 mm OD clamping uniformly around the circumference.", "The 177/221 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430211X; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-430211X?", "a": "4T-430211X is a double-row tapered roller bearing of TDO (back-to-back) construction: 55 mm bore, 100 mm outside diameter and 51 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 177 kN, C0 221 kN (2203E prints a dash for Cu on this size), grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 1.57 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 55 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-430211X belongs to the light-duty 430-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-430211X be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 51 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 430211X mean?", "a": "Suffix reading on 430211X: X marks the boundary-dimension revision of the base number (D and width differ from the plain number of the same bore); suffixed variants are separate order numbers and are not interchangeable articles." }, { "q": "Why does 4T-430211X list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430211X at 4,100 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "430211X", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "430211x", "4t-430211x", "430211X", "4T-430211X" ], "locale_variants": {} }, { "sku": "432211U", "brand": "NTN", "manufacturer_designation": "NTN 4T-432211U", "series": "4t-432-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 100, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 206, "static_load_kN": 269, "fatigue_load_limit_kN": 33, "limiting_speed_rpm": 3100, "max_rpm": 3100, "speed_oil_rpm": 4100, "weight_g": 1890, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-432211U denotes the heavy-duty 432-family TDO double-row series — a 55 mm bore double-row tapered unit rated 206 kN basic dynamic and 269 kN static. Suffix reading on 432211U: U marks the uprated/reinforced internal design, a separate order number with higher capacity than the basic execution; suffixed variants are separate order numbers and are not interchangeable articles. Double-row capacity is not twice a single-row bearing: the printed 206 kN C already accounts for load sharing between the two rows of 4T-432211U, so apply it directly in the L10 calculation. TDO construction means the two cone assemblies of 4T-432211U face away from each other inside one double cup: the load lines diverge outward, giving a wide effective spread and high moment stiffness for the 55 mm shaft. Fillet radii and shoulder heights must follow the 2203E mounting table for 4T-432211U; the double cup must seat square across its full 60 mm width.", "applications": [ "extruder and mixer drive shafts", "construction-equipment swing and pivot shafts", "industrial gearbox shafts in a single locating position", "rolling-mill work-roll and backup auxiliary positions" ], "failure_modes": [ "edge loading on one row when the housing seats the double cup cocked across its width", "brinelling of both rows from a mounting blow transmitted through the roller complements", "preload loss and hammering noise when the cup clamping loosens and the unit gains axial float", "pressed-steel cage pocket wear from roller skid at light load and high speed", "water-induced pitting when washdown reaches the open unit without external seals" ], "pitfalls": [ "Gearbox positions of this 55 mm class rely on the preset clearance of 4T-432211U; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 432 heavy plan gives 4T-432211U its 60 mm width and 206 kN rating at the 55 mm bore; do not downgrade to a 430-family unit of the same bore without re-checking C, C0 and the 33 kN Cu.", "Order by the full 432211U code including suffixes — U, X, DX, E1 and UTG variants share the 55 mm bore but are different articles with different internal geometry.", "The 206 kN C already includes two-row load sharing — do not double it when pairing the unit with a floating bearing in the L10 calculation.", "Clamping the double cup with a cocked end cover pinches one row: tighten the 100 mm OD clamping uniformly around the circumference.", "The 206/269 kN ratings and 33 kN Cu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-432211U; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-432211U?", "a": "4T-432211U is a double-row tapered roller bearing of TDO (back-to-back) construction: 55 mm bore, 100 mm outside diameter and 60 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 206 kN, C0 269 kN, Cu 33 kN, grease limiting speed 3,100 r/min, oil speed 4,100 r/min, mass about 1.89 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 55 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-432211U belongs to the heavy-duty 432-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-432211U be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 60 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 432211U mean?", "a": "Suffix reading on 432211U: U marks the uprated/reinforced internal design, a separate order number with higher capacity than the basic execution; suffixed variants are separate order numbers and are not interchangeable articles." }, { "q": "Why does 4T-432211U list two speeds, 3,100 and 4,100 r/min?", "a": "The lower figure, 3,100 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-432211U at 4,100 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "432211U", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "432211u", "4t-432211u", "432211U", "4T-432211U" ], "locale_variants": {} }, { "sku": "430311DX", "brand": "NTN", "manufacturer_designation": "NTN 4T-430311DX", "series": "4t-430-series", "type": "tapered_roller", "d_mm": 55, "D_mm": 120, "B_mm": 70, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel", "dynamic_load_kN": 251, "static_load_kN": 305, "limiting_speed_rpm": 2400, "max_rpm": 2400, "speed_oil_rpm": 3100, "weight_g": 3420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ANSI ABMA 19.2", "naming_rule_text": "4T-430311DX is the NTN 4T catalogue entry for a 55×120×70 mm double-row tapered roller bearing — the TDO arrangement reacts radial load plus thrust in both directions without a second bearing. Reading the designation: the last two digits 11 are the bore code, ×5 = 55 mm (codes 00–03 use the 10/12/15/17 exception table); the leading digits place the bearing in the light-duty 430-family TDO double-row series. The 32.5 mm radial section over the 55 mm bore carries two roller rows across the 70 mm width; abutment shoulders must clear both cone bores and the double-cup OD. Because the unit is preset, mounting 4T-430311DX resembles mounting a double-row spherical or cylindrical bearing: seat the unit, clamp axially to the stated end cover torque, and verify rotation — no end-play measurement is required. Fillet radii and shoulder heights must follow the 2203E mounting table for 4T-430311DX; the double cup must seat square across its full 70 mm width.", "applications": [ "mining conveyor drive and head pulleys", "paper-machine roll and press supports", "extruder and mixer drive shafts", "construction-equipment swing and pivot shafts" ], "failure_modes": [ "roller large-end smearing against the cone ribs when one row of the unit runs starved of lubricant", "one-row flaking when a bent shaft concentrates the combined load on a single row of the pair", "overheated running after a field attempt to \"tighten up\" the factory-set internal clearance", "cage damage when the unit is lifted by one cone instead of the double cup during fitting", "thermal distress when the oil supply sized for one row starves the second row" ], "pitfalls": [ "Gearbox positions of this 55 mm class rely on the preset clearance of 4T-430311DX; shimming or nut-tightening the unit like a single-row pair overruns the factory setting and runs the rows hot.", "The 430 light plan keeps 4T-430311DX narrower and faster than the 432 heavy execution of the same 55 mm bore; where shock or a high thrust share dominates, verify whether the heavier 432-family row is the intended position.", "Order by the full 430311DX code including suffixes — U, X, DX, E1 and UTG variants share the 55 mm bore but are different articles with different internal geometry.", "Clamping the double cup with a cocked end cover pinches one row: tighten the 120 mm OD clamping uniformly around the circumference.", "An unloaded 4T-430311DX near 2,400 r/min lets rollers skid; ensure a minimum load or light spring preload on high-speed positions.", "The 251/305 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-430311DX; internal geometry legitimately differs between manufacturers, so re-verify ratings, clearance class and suffix before substituting another make on a rated drive." ], "faq": [ { "q": "What are the dimensions and catalogue ratings of NTN 4T-430311DX?", "a": "4T-430311DX is a double-row tapered roller bearing of TDO (back-to-back) construction: 55 mm bore, 120 mm outside diameter and 70 mm overall width. From NTN Ball and Roller Bearings CAT.No.2203E: C 251 kN, C0 305 kN (2203E prints a dash for Cu on this size), grease limiting speed 2,400 r/min, oil speed 3,100 r/min, mass about 3.42 kg. It is an open, preset-clearance unit with pressed-steel cages." }, { "q": "What is the difference between the NTN 430 and 432 double-row series at 55 mm bore?", "a": "Both are TDO double-row tapered roller units, but 430 is the light plan and 432 the heavy plan: at the same bore the 432 execution is wider and heavier with higher load ratings. 4T-430311DX belongs to the light-duty 430-family TDO double-row series. Large sizes continue the plans as 4130/4131/4230/4231 (430 family) and 3230/3231 (432 family)." }, { "q": "Can the internal clearance of 4T-430311DX be adjusted at mounting?", "a": "No. The TDO unit — two cone assemblies against one double cup — is ground and set by NTN at the factory, and the 70 mm overall width is the finished dimension. Mounting sets no end play: seat the unit square, clamp the cup uniformly and verify free rotation. Field re-adjustment overloads one row." }, { "q": "What do the suffix letters on 430311DX mean?", "a": "Suffix reading on 430311DX: X marks the boundary-dimension revision of the base number (D and width differ from the plain number of the same bore); suffixed variants are separate order numbers and are not interchangeable articles." }, { "q": "Why does 4T-430311DX list two speeds, 2,400 and 3,100 r/min?", "a": "The lower figure, 2,400 r/min, is the grease-lubricated limiting speed for the two rows and their cages. With oil lubrication NTN rates 4T-430311DX at 3,100 r/min because oil removes heat from both roller rows better — the housing feed must reach both rows through the double cup." } ], "cross_ref": [ { "equiv_sku": "430311DX", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.ntnglobal.com/en/products/catalog/pdf/2203E_b02.pdf#page=194", "catalog_ver": "NTN 2203E 2026-09-25", "extracted_at": "2026-10-01", "last_verified": "2026-10-01", "confidence_score": 0.7, "status": "published", "aliases": [ "430311dx", "4t-430311dx", "430311DX", "4T-430311DX" ], "locale_variants": {} } ]