[ { "sku": "51100", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 10, "D_mm": 24, "B_mm": 9, "seal_type": "open", "dynamic_load_kN": 10, "static_load_kN": 14, "fatigue_load_limit_kN": 0.63, "limiting_speed_rpm": 6700, "speed_oil_rpm": 9500, "weight_g": 21, "manufacturer_designation": "51100", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51100 carries bore code 00 = 10 mm. The ISO 104 boundary dimensions are 10 mm bore, 24 mm outside diameter and 9 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "light-duty fan axial restraint", "power tool thrust collars", "small electric motor axial positioning", "appliance gearbox thrust washers" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At a 10 mm bore, thrust ball washers are thin and easily distorted; press the shaft washer on with a proper sleeve — never hammer it or the raceway will brinell.", "The 511xx light section at 10 mm bore uses a smaller 24 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "The 9 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51100.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51100 thrust ball bearing?", "a": "A 51100 thrust ball bearing has a 10 mm bore, 24 mm outside diameter and 9 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51100 bore code work?", "a": "The last two digits of 51100 are bore code 00, giving 00 × 5 = 10 mm bore. The 24 mm outside diameter and 9 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51100 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 10 mm bore?", "a": "The 511xx is the light section: 24×9 mm with a 7.0 mm radial section at 10 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51200", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 10, "D_mm": 26, "B_mm": 11, "seal_type": "open", "dynamic_load_kN": 12.7, "static_load_kN": 17.1, "fatigue_load_limit_kN": 0.77, "limiting_speed_rpm": 5800, "speed_oil_rpm": 8300, "weight_g": 30, "manufacturer_designation": "51200", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51200 carries bore code 00 = 10 mm. The ISO 104 boundary dimensions are 10 mm bore, 26 mm outside diameter and 11 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "small electric motor axial positioning", "appliance gearbox thrust washers", "small pump axial load support", "instrument and office machine spindles" ], "failure_modes": [ "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading" ], "pitfalls": [ "At a 10 mm bore, thrust ball washers are thin and easily distorted; press the shaft washer on with a proper sleeve — never hammer it or the raceway will brinell.", "The 512xx medium-light section at 10 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 26 mm OD and 11 mm height.", "Thrust ball bearings carry axial load only — never apply radial load to 51200; the flat washers will skid and score.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51200 thrust ball bearing?", "a": "A 51200 thrust ball bearing has a 10 mm bore, 26 mm outside diameter and 11 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51200 bore code work?", "a": "The last two digits of 51200 are bore code 00, giving 00 × 5 = 10 mm bore. The 26 mm outside diameter and 11 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51200 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 10 mm bore?", "a": "The 512xx is the medium-light section: 26×11 mm, 8.0 mm radial section at 10 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51101", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 12, "D_mm": 26, "B_mm": 9, "seal_type": "open", "dynamic_load_kN": 10.3, "static_load_kN": 15.4, "fatigue_load_limit_kN": 0.695, "limiting_speed_rpm": 6400, "speed_oil_rpm": 9200, "weight_g": 23, "manufacturer_designation": "51101", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51101 carries bore code 01 = 12 mm. The ISO 104 boundary dimensions are 12 mm bore, 26 mm outside diameter and 9 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "small electric motor axial positioning", "appliance gearbox thrust washers", "small pump axial load support", "instrument and office machine spindles" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "At a 12 mm bore, thrust ball washers are thin and easily distorted; press the shaft washer on with a proper sleeve — never hammer it or the raceway will brinell.", "The 511xx light section at 12 mm bore uses a smaller 26 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Thrust ball bearings carry axial load only — never apply radial load to 51101; the flat washers will skid and score.", "The shaft washer (bore 12 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51101 thrust ball bearing?", "a": "A 51101 thrust ball bearing has a 12 mm bore, 26 mm outside diameter and 9 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51101 bore code work?", "a": "The last two digits of 51101 are bore code 01, giving 01 × 5 = 12 mm bore. The 26 mm outside diameter and 9 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51101 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 12 mm bore?", "a": "The 511xx is the light section: 26×9 mm with a 7.0 mm radial section at 12 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51201", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 12, "D_mm": 28, "B_mm": 11, "seal_type": "open", "dynamic_load_kN": 13.2, "static_load_kN": 19, "fatigue_load_limit_kN": 0.86, "limiting_speed_rpm": 5600, "speed_oil_rpm": 8000, "weight_g": 34, "manufacturer_designation": "51201", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51201 carries bore code 01 = 12 mm. The ISO 104 boundary dimensions are 12 mm bore, 28 mm outside diameter and 11 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "small pump axial load support", "instrument and office machine spindles", "light-duty fan axial restraint", "power tool thrust collars" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "At a 12 mm bore, thrust ball washers are thin and easily distorted; press the shaft washer on with a proper sleeve — never hammer it or the raceway will brinell.", "The 512xx medium-light section at 12 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 28 mm OD and 11 mm height.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "The 11 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51201." ], "faq": [ { "q": "What are the dimensions of a 51201 thrust ball bearing?", "a": "A 51201 thrust ball bearing has a 12 mm bore, 28 mm outside diameter and 11 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51201 bore code work?", "a": "The last two digits of 51201 are bore code 01, giving 01 × 5 = 12 mm bore. The 28 mm outside diameter and 11 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51201 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 12 mm bore?", "a": "The 512xx is the medium-light section: 28×11 mm, 8.0 mm radial section at 12 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51102", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 15, "D_mm": 28, "B_mm": 9, "seal_type": "open", "dynamic_load_kN": 10.5, "static_load_kN": 16.8, "fatigue_load_limit_kN": 0.755, "limiting_speed_rpm": 6200, "speed_oil_rpm": 8800, "weight_g": 24, "manufacturer_designation": "51102", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51102 carries bore code 02 = 15 mm. The ISO 104 boundary dimensions are 15 mm bore, 28 mm outside diameter and 9 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "instrument and office machine spindles", "light-duty fan axial restraint", "power tool thrust collars", "small electric motor axial positioning" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 15 mm bore, thrust ball washers are thin and easily distorted; press the shaft washer on with a proper sleeve — never hammer it or the raceway will brinell.", "The 511xx light section at 15 mm bore uses a smaller 28 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure.", "The 9 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51102." ], "faq": [ { "q": "What are the dimensions of a 51102 thrust ball bearing?", "a": "A 51102 thrust ball bearing has a 15 mm bore, 28 mm outside diameter and 9 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51102 bore code work?", "a": "The last two digits of 51102 are bore code 02, giving 02 × 5 = 15 mm bore. The 28 mm outside diameter and 9 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51102 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 15 mm bore?", "a": "The 511xx is the light section: 28×9 mm with a 6.5 mm radial section at 15 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51202", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 15, "D_mm": 32, "B_mm": 12, "seal_type": "open", "dynamic_load_kN": 16.6, "static_load_kN": 24.8, "fatigue_load_limit_kN": 1.12, "limiting_speed_rpm": 5000, "speed_oil_rpm": 7100, "weight_g": 46, "manufacturer_designation": "51202", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51202 carries bore code 02 = 15 mm. The ISO 104 boundary dimensions are 15 mm bore, 32 mm outside diameter and 12 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "power tool thrust collars", "small electric motor axial positioning", "appliance gearbox thrust washers", "small pump axial load support" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At a 15 mm bore, thrust ball washers are thin and easily distorted; press the shaft washer on with a proper sleeve — never hammer it or the raceway will brinell.", "The 512xx medium-light section at 15 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 32 mm OD and 12 mm height.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back.", "The shaft washer (bore 15 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51202 thrust ball bearing?", "a": "A 51202 thrust ball bearing has a 15 mm bore, 32 mm outside diameter and 12 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51202 bore code work?", "a": "The last two digits of 51202 are bore code 02, giving 02 × 5 = 15 mm bore. The 32 mm outside diameter and 12 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51202 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 15 mm bore?", "a": "The 512xx is the medium-light section: 32×12 mm, 8.5 mm radial section at 15 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51103", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 17, "D_mm": 30, "B_mm": 9, "seal_type": "open", "dynamic_load_kN": 10.8, "static_load_kN": 18.2, "fatigue_load_limit_kN": 0.82, "limiting_speed_rpm": 6000, "speed_oil_rpm": 8500, "weight_g": 26, "manufacturer_designation": "51103", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51103 carries bore code 03 = 17 mm. The ISO 104 boundary dimensions are 17 mm bore, 30 mm outside diameter and 9 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "power tool thrust collars", "small electric motor axial positioning", "appliance gearbox thrust washers", "small pump axial load support" ], "failure_modes": [ "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading" ], "pitfalls": [ "At a 17 mm bore, thrust ball washers are thin and easily distorted; press the shaft washer on with a proper sleeve — never hammer it or the raceway will brinell.", "The 511xx light section at 17 mm bore uses a smaller 30 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back.", "Thrust ball bearings carry axial load only — never apply radial load to 51103; the flat washers will skid and score." ], "faq": [ { "q": "What are the dimensions of a 51103 thrust ball bearing?", "a": "A 51103 thrust ball bearing has a 17 mm bore, 30 mm outside diameter and 9 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51103 bore code work?", "a": "The last two digits of 51103 are bore code 03, giving 03 × 5 = 17 mm bore. The 30 mm outside diameter and 9 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51103 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 17 mm bore?", "a": "The 511xx is the light section: 30×9 mm with a 6.5 mm radial section at 17 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51203", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 17, "D_mm": 35, "B_mm": 12, "seal_type": "open", "dynamic_load_kN": 17.2, "static_load_kN": 27.3, "fatigue_load_limit_kN": 1.23, "limiting_speed_rpm": 4800, "speed_oil_rpm": 6800, "weight_g": 54, "manufacturer_designation": "51203", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51203 carries bore code 03 = 17 mm. The ISO 104 boundary dimensions are 17 mm bore, 35 mm outside diameter and 12 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "appliance gearbox thrust washers", "small pump axial load support", "instrument and office machine spindles", "light-duty fan axial restraint" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "At a 17 mm bore, thrust ball washers are thin and easily distorted; press the shaft washer on with a proper sleeve — never hammer it or the raceway will brinell.", "The 512xx medium-light section at 17 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 35 mm OD and 12 mm height.", "The shaft washer (bore 17 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure." ], "faq": [ { "q": "What are the dimensions of a 51203 thrust ball bearing?", "a": "A 51203 thrust ball bearing has a 17 mm bore, 35 mm outside diameter and 12 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51203 bore code work?", "a": "The last two digits of 51203 are bore code 03, giving 03 × 5 = 17 mm bore. The 35 mm outside diameter and 12 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51203 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 17 mm bore?", "a": "The 512xx is the medium-light section: 35×12 mm, 9.0 mm radial section at 17 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51104", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 20, "D_mm": 35, "B_mm": 10, "seal_type": "open", "dynamic_load_kN": 14.2, "static_load_kN": 24.5, "fatigue_load_limit_kN": 1.05, "limiting_speed_rpm": 5300, "speed_oil_rpm": 7500, "weight_g": 36, "manufacturer_designation": "51104", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51104 carries bore code 04 = 20 mm. The ISO 104 boundary dimensions are 20 mm bore, 35 mm outside diameter and 10 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "small pump axial load support", "instrument and office machine spindles", "light-duty fan axial restraint", "power tool thrust collars" ], "failure_modes": [ "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force" ], "pitfalls": [ "At a 20 mm bore, thrust ball washers are thin and easily distorted; press the shaft washer on with a proper sleeve — never hammer it or the raceway will brinell.", "The 511xx light section at 20 mm bore uses a smaller 35 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure." ], "faq": [ { "q": "What are the dimensions of a 51104 thrust ball bearing?", "a": "A 51104 thrust ball bearing has a 20 mm bore, 35 mm outside diameter and 10 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51104 bore code work?", "a": "The last two digits of 51104 are bore code 04, giving 04 × 5 = 20 mm bore. The 35 mm outside diameter and 10 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51104 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 20 mm bore?", "a": "The 511xx is the light section: 35×10 mm with a 7.5 mm radial section at 20 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51204", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 20, "D_mm": 40, "B_mm": 14, "seal_type": "open", "dynamic_load_kN": 22.3, "static_load_kN": 37.5, "fatigue_load_limit_kN": 1.52, "limiting_speed_rpm": 4300, "speed_oil_rpm": 6000, "weight_g": 75, "manufacturer_designation": "51204", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51204 carries bore code 04 = 20 mm. The ISO 104 boundary dimensions are 20 mm bore, 40 mm outside diameter and 14 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "light-duty fan axial restraint", "power tool thrust collars", "small electric motor axial positioning", "appliance gearbox thrust washers" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 20 mm bore, thrust ball washers are thin and easily distorted; press the shaft washer on with a proper sleeve — never hammer it or the raceway will brinell.", "The 512xx medium-light section at 20 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 40 mm OD and 14 mm height.", "The 14 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51204.", "Thrust ball bearings carry axial load only — never apply radial load to 51204; the flat washers will skid and score." ], "faq": [ { "q": "What are the dimensions of a 51204 thrust ball bearing?", "a": "A 51204 thrust ball bearing has a 20 mm bore, 40 mm outside diameter and 14 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51204 bore code work?", "a": "The last two digits of 51204 are bore code 04, giving 04 × 5 = 20 mm bore. The 40 mm outside diameter and 14 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51204 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 20 mm bore?", "a": "The 512xx is the medium-light section: 40×14 mm, 10.0 mm radial section at 20 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51305", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 52, "B_mm": 18, "seal_type": "open", "dynamic_load_kN": 35.5, "static_load_kN": 71, "fatigue_load_limit_kN": 2.84, "limiting_speed_rpm": 3200, "speed_oil_rpm": 4600, "weight_g": 176, "manufacturer_designation": "51305", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51305 carries bore code 05 = 25 mm. The ISO 104 boundary dimensions are 25 mm bore, 52 mm outside diameter and 18 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "industrial fan axial restraint", "electric motor axial positioning", "pump and compressor thrust support", "gearbox axial load management" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 25 mm bore, check shaft shoulder runout before fitting 51305; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 513xx medium section gains rating at 25 mm bore through a larger 52 mm OD and 18 mm height; the heavier assembly also trades away some speed versus a 512xx.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51305 thrust ball bearing?", "a": "A 51305 thrust ball bearing has a 25 mm bore, 52 mm outside diameter and 18 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51305 bore code work?", "a": "The last two digits of 51305 are bore code 05, giving 05 × 5 = 25 mm bore. The 52 mm outside diameter and 18 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51305 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 25 mm bore?", "a": "The 513xx is the medium section: 52×18 mm, 13.5 mm radial section at 25 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51405", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 60, "B_mm": 24, "seal_type": "open", "dynamic_load_kN": 55.5, "static_load_kN": 105, "fatigue_load_limit_kN": 4.75, "limiting_speed_rpm": 2400, "speed_oil_rpm": 3500, "weight_g": 383, "manufacturer_designation": "51405", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51405 carries bore code 05 = 25 mm. The ISO 104 boundary dimensions are 25 mm bore, 60 mm outside diameter and 24 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "pump and compressor thrust support", "gearbox axial load management", "conveyor drive thrust washers", "agricultural equipment spindle thrust" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At a 25 mm bore, check shaft shoulder runout before fitting 51405; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 514xx heavy section at 25 mm bore (60 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "The shaft washer (bore 25 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51405 thrust ball bearing?", "a": "A 51405 thrust ball bearing has a 25 mm bore, 60 mm outside diameter and 24 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51405 bore code work?", "a": "The last two digits of 51405 are bore code 05, giving 05 × 5 = 25 mm bore. The 60 mm outside diameter and 24 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51405 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 25 mm bore?", "a": "The 514xx is the heavy section: 60×24 mm, 17.5 mm radial section at 25 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51105", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 42, "B_mm": 11, "seal_type": "open", "dynamic_load_kN": 15.2, "static_load_kN": 29, "fatigue_load_limit_kN": 1.25, "limiting_speed_rpm": 4800, "speed_oil_rpm": 6800, "weight_g": 41, "manufacturer_designation": "51105", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51105 carries bore code 05 = 25 mm. The ISO 104 boundary dimensions are 25 mm bore, 42 mm outside diameter and 11 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "pump and compressor thrust support", "gearbox axial load management", "conveyor drive thrust washers", "agricultural equipment spindle thrust" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "At a 25 mm bore, check shaft shoulder runout before fitting 51105; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 511xx light section at 25 mm bore uses a smaller 42 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "The shaft washer (bore 25 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51105 thrust ball bearing?", "a": "A 51105 thrust ball bearing has a 25 mm bore, 42 mm outside diameter and 11 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51105 bore code work?", "a": "The last two digits of 51105 are bore code 05, giving 05 × 5 = 25 mm bore. The 42 mm outside diameter and 11 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51105 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 25 mm bore?", "a": "The 511xx is the light section: 42×11 mm with an 8.5 mm radial section at 25 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51205", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 25, "D_mm": 47, "B_mm": 15, "seal_type": "open", "dynamic_load_kN": 26, "static_load_kN": 44, "fatigue_load_limit_kN": 1.9, "limiting_speed_rpm": 3800, "speed_oil_rpm": 5400, "weight_g": 110, "manufacturer_designation": "51205", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51205 carries bore code 05 = 25 mm. The ISO 104 boundary dimensions are 25 mm bore, 47 mm outside diameter and 15 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "conveyor drive thrust washers", "agricultural equipment spindle thrust", "industrial fan axial restraint", "electric motor axial positioning" ], "failure_modes": [ "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force" ], "pitfalls": [ "At a 25 mm bore, check shaft shoulder runout before fitting 51205; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 512xx medium-light section at 25 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 47 mm OD and 15 mm height.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51205 thrust ball bearing?", "a": "A 51205 thrust ball bearing has a 25 mm bore, 47 mm outside diameter and 15 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51205 bore code work?", "a": "The last two digits of 51205 are bore code 05, giving 05 × 5 = 25 mm bore. The 47 mm outside diameter and 15 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51205 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 25 mm bore?", "a": "The 512xx is the medium-light section: 47×15 mm, 11.0 mm radial section at 25 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51406", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 70, "B_mm": 28, "seal_type": "open", "dynamic_load_kN": 72, "static_load_kN": 155, "fatigue_load_limit_kN": 6.05, "limiting_speed_rpm": 1900, "speed_oil_rpm": 2800, "weight_g": 550, "manufacturer_designation": "51406", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51406 carries bore code 06 = 30 mm. The ISO 104 boundary dimensions are 30 mm bore, 70 mm outside diameter and 28 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "electric motor axial positioning", "pump and compressor thrust support", "gearbox axial load management", "conveyor drive thrust washers" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 30 mm bore, check shaft shoulder runout before fitting 51406; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 514xx heavy section at 30 mm bore (70 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "Thrust ball bearings carry axial load only — never apply radial load to 51406; the flat washers will skid and score.", "The 28 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51406." ], "faq": [ { "q": "What are the dimensions of a 51406 thrust ball bearing?", "a": "A 51406 thrust ball bearing has a 30 mm bore, 70 mm outside diameter and 28 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51406 bore code work?", "a": "The last two digits of 51406 are bore code 06, giving 06 × 5 = 30 mm bore. The 70 mm outside diameter and 28 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51406 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 30 mm bore?", "a": "The 514xx is the heavy section: 70×28 mm, 20.0 mm radial section at 30 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51106", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 47, "B_mm": 11, "seal_type": "open", "dynamic_load_kN": 16, "static_load_kN": 33, "fatigue_load_limit_kN": 1.4, "limiting_speed_rpm": 4500, "speed_oil_rpm": 6300, "weight_g": 48, "manufacturer_designation": "51106", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51106 carries bore code 06 = 30 mm. The ISO 104 boundary dimensions are 30 mm bore, 47 mm outside diameter and 11 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "electric motor axial positioning", "pump and compressor thrust support", "gearbox axial load management", "conveyor drive thrust washers" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "At a 30 mm bore, check shaft shoulder runout before fitting 51106; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 511xx light section at 30 mm bore uses a smaller 47 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Thrust ball bearings carry axial load only — never apply radial load to 51106; the flat washers will skid and score.", "The shaft washer (bore 30 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51106 thrust ball bearing?", "a": "A 51106 thrust ball bearing has a 30 mm bore, 47 mm outside diameter and 11 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51106 bore code work?", "a": "The last two digits of 51106 are bore code 06, giving 06 × 5 = 30 mm bore. The 47 mm outside diameter and 11 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51106 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 30 mm bore?", "a": "The 511xx is the light section: 47×11 mm with an 8.5 mm radial section at 30 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51206", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 52, "B_mm": 16, "seal_type": "open", "dynamic_load_kN": 26, "static_load_kN": 50, "fatigue_load_limit_kN": 2.2, "limiting_speed_rpm": 3600, "speed_oil_rpm": 5100, "weight_g": 130, "manufacturer_designation": "51206", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51206 carries bore code 06 = 30 mm. The ISO 104 boundary dimensions are 30 mm bore, 52 mm outside diameter and 16 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "gearbox axial load management", "conveyor drive thrust washers", "agricultural equipment spindle thrust", "industrial fan axial restraint" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "At a 30 mm bore, check shaft shoulder runout before fitting 51206; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 512xx medium-light section at 30 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 52 mm OD and 16 mm height.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "The 16 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51206." ], "faq": [ { "q": "What are the dimensions of a 51206 thrust ball bearing?", "a": "A 51206 thrust ball bearing has a 30 mm bore, 52 mm outside diameter and 16 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51206 bore code work?", "a": "The last two digits of 51206 are bore code 06, giving 06 × 5 = 30 mm bore. The 52 mm outside diameter and 16 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51206 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 30 mm bore?", "a": "The 512xx is the medium-light section: 52×16 mm, 11.0 mm radial section at 30 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51306", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 30, "D_mm": 60, "B_mm": 21, "seal_type": "open", "dynamic_load_kN": 43, "static_load_kN": 86, "fatigue_load_limit_kN": 3.1, "limiting_speed_rpm": 2800, "speed_oil_rpm": 4000, "weight_g": 269, "manufacturer_designation": "51306", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51306 carries bore code 06 = 30 mm. The ISO 104 boundary dimensions are 30 mm bore, 60 mm outside diameter and 21 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "agricultural equipment spindle thrust", "industrial fan axial restraint", "electric motor axial positioning", "pump and compressor thrust support" ], "failure_modes": [ "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force" ], "pitfalls": [ "At a 30 mm bore, check shaft shoulder runout before fitting 51306; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 513xx medium section gains rating at 30 mm bore through a larger 60 mm OD and 21 mm height; the heavier assembly also trades away some speed versus a 512xx.", "The 21 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51306.", "The shaft washer (bore 30 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51306 thrust ball bearing?", "a": "A 51306 thrust ball bearing has a 30 mm bore, 60 mm outside diameter and 21 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51306 bore code work?", "a": "The last two digits of 51306 are bore code 06, giving 06 × 5 = 30 mm bore. The 60 mm outside diameter and 21 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51306 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 30 mm bore?", "a": "The 513xx is the medium section: 60×21 mm, 15.0 mm radial section at 30 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51407", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 80, "B_mm": 32, "seal_type": "open", "dynamic_load_kN": 87, "static_load_kN": 155, "fatigue_load_limit_kN": 7, "limiting_speed_rpm": 1900, "speed_oil_rpm": 2800, "weight_g": 759, "manufacturer_designation": "51407", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51407 carries bore code 07 = 35 mm. The ISO 104 boundary dimensions are 35 mm bore, 80 mm outside diameter and 32 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "industrial fan axial restraint", "electric motor axial positioning", "pump and compressor thrust support", "gearbox axial load management" ], "failure_modes": [ "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force" ], "pitfalls": [ "At a 35 mm bore, check shaft shoulder runout before fitting 51407; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 514xx heavy section at 35 mm bore (80 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure." ], "faq": [ { "q": "What are the dimensions of a 51407 thrust ball bearing?", "a": "A 51407 thrust ball bearing has a 35 mm bore, 80 mm outside diameter and 32 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51407 bore code work?", "a": "The last two digits of 51407 are bore code 07, giving 07 × 5 = 35 mm bore. The 80 mm outside diameter and 32 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51407 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 35 mm bore?", "a": "The 514xx is the heavy section: 80×32 mm, 22.5 mm radial section at 35 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51107", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 52, "B_mm": 12, "seal_type": "open", "dynamic_load_kN": 20.4, "static_load_kN": 44.5, "fatigue_load_limit_kN": 2.02, "limiting_speed_rpm": 3900, "speed_oil_rpm": 5600, "weight_g": 85, "manufacturer_designation": "51107", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51107 carries bore code 07 = 35 mm. The ISO 104 boundary dimensions are 35 mm bore, 52 mm outside diameter and 12 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "industrial fan axial restraint", "electric motor axial positioning", "pump and compressor thrust support", "gearbox axial load management" ], "failure_modes": [ "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading" ], "pitfalls": [ "At a 35 mm bore, check shaft shoulder runout before fitting 51107; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 511xx light section at 35 mm bore uses a smaller 52 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back.", "Thrust ball bearings carry axial load only — never apply radial load to 51107; the flat washers will skid and score." ], "faq": [ { "q": "What are the dimensions of a 51107 thrust ball bearing?", "a": "A 51107 thrust ball bearing has a 35 mm bore, 52 mm outside diameter and 12 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51107 bore code work?", "a": "The last two digits of 51107 are bore code 07, giving 07 × 5 = 35 mm bore. The 52 mm outside diameter and 12 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51107 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 35 mm bore?", "a": "The 511xx is the light section: 52×12 mm with an 8.5 mm radial section at 35 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51207", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 62, "B_mm": 18, "seal_type": "open", "dynamic_load_kN": 39, "static_load_kN": 78, "fatigue_load_limit_kN": 3.55, "limiting_speed_rpm": 2900, "speed_oil_rpm": 4200, "weight_g": 215, "manufacturer_designation": "51207", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51207 carries bore code 07 = 35 mm. The ISO 104 boundary dimensions are 35 mm bore, 62 mm outside diameter and 18 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "pump and compressor thrust support", "gearbox axial load management", "conveyor drive thrust washers", "agricultural equipment spindle thrust" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "At a 35 mm bore, check shaft shoulder runout before fitting 51207; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 512xx medium-light section at 35 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 62 mm OD and 18 mm height.", "The shaft washer (bore 35 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure." ], "faq": [ { "q": "What are the dimensions of a 51207 thrust ball bearing?", "a": "A 51207 thrust ball bearing has a 35 mm bore, 62 mm outside diameter and 18 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51207 bore code work?", "a": "The last two digits of 51207 are bore code 07, giving 07 × 5 = 35 mm bore. The 62 mm outside diameter and 18 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51207 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 35 mm bore?", "a": "The 512xx is the medium-light section: 62×18 mm, 13.5 mm radial section at 35 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51307", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 35, "D_mm": 68, "B_mm": 24, "seal_type": "open", "dynamic_load_kN": 55.5, "static_load_kN": 105, "fatigue_load_limit_kN": 4.75, "limiting_speed_rpm": 2400, "speed_oil_rpm": 3500, "weight_g": 383, "manufacturer_designation": "51307", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51307 carries bore code 07 = 35 mm. The ISO 104 boundary dimensions are 35 mm bore, 68 mm outside diameter and 24 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "conveyor drive thrust washers", "agricultural equipment spindle thrust", "industrial fan axial restraint", "electric motor axial positioning" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "At a 35 mm bore, check shaft shoulder runout before fitting 51307; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 513xx medium section gains rating at 35 mm bore through a larger 68 mm OD and 24 mm height; the heavier assembly also trades away some speed versus a 512xx.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure.", "Thrust ball bearings carry axial load only — never apply radial load to 51307; the flat washers will skid and score." ], "faq": [ { "q": "What are the dimensions of a 51307 thrust ball bearing?", "a": "A 51307 thrust ball bearing has a 35 mm bore, 68 mm outside diameter and 24 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51307 bore code work?", "a": "The last two digits of 51307 are bore code 07, giving 07 × 5 = 35 mm bore. The 68 mm outside diameter and 24 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51307 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 35 mm bore?", "a": "The 513xx is the medium section: 68×24 mm, 16.5 mm radial section at 35 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51408", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 90, "B_mm": 36, "seal_type": "open", "dynamic_load_kN": 112, "static_load_kN": 205, "fatigue_load_limit_kN": 9.25, "limiting_speed_rpm": 1700, "speed_oil_rpm": 2500, "weight_g": 1080, "manufacturer_designation": "51408", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51408 carries bore code 08 = 40 mm. The ISO 104 boundary dimensions are 40 mm bore, 90 mm outside diameter and 36 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "agricultural equipment spindle thrust", "industrial fan axial restraint", "electric motor axial positioning", "pump and compressor thrust support" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "At a 40 mm bore, check shaft shoulder runout before fitting 51408; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 514xx heavy section at 40 mm bore (90 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "The 36 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51408.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51408 thrust ball bearing?", "a": "A 51408 thrust ball bearing has a 40 mm bore, 90 mm outside diameter and 36 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51408 bore code work?", "a": "The last two digits of 51408 are bore code 08, giving 08 × 5 = 40 mm bore. The 90 mm outside diameter and 36 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51408 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 40 mm bore?", "a": "The 514xx is the heavy section: 90×36 mm, 25.0 mm radial section at 40 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51108", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 60, "B_mm": 13, "seal_type": "open", "dynamic_load_kN": 26.9, "static_load_kN": 63, "fatigue_load_limit_kN": 2.84, "limiting_speed_rpm": 3500, "speed_oil_rpm": 5000, "weight_g": 125, "manufacturer_designation": "51108", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51108 carries bore code 08 = 40 mm. The ISO 104 boundary dimensions are 40 mm bore, 60 mm outside diameter and 13 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "agricultural equipment spindle thrust", "industrial fan axial restraint", "electric motor axial positioning", "pump and compressor thrust support" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At a 40 mm bore, check shaft shoulder runout before fitting 51108; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 511xx light section at 40 mm bore uses a smaller 60 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "The 13 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51108.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51108 thrust ball bearing?", "a": "A 51108 thrust ball bearing has a 40 mm bore, 60 mm outside diameter and 13 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51108 bore code work?", "a": "The last two digits of 51108 are bore code 08, giving 08 × 5 = 40 mm bore. The 60 mm outside diameter and 13 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51108 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 40 mm bore?", "a": "The 511xx is the light section: 60×13 mm with a 10.0 mm radial section at 40 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51208", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 68, "B_mm": 19, "seal_type": "open", "dynamic_load_kN": 47, "static_load_kN": 98.5, "fatigue_load_limit_kN": 4.45, "limiting_speed_rpm": 2700, "speed_oil_rpm": 3900, "weight_g": 276, "manufacturer_designation": "51208", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51208 carries bore code 08 = 40 mm. The ISO 104 boundary dimensions are 40 mm bore, 68 mm outside diameter and 19 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "electric motor axial positioning", "pump and compressor thrust support", "gearbox axial load management", "conveyor drive thrust washers" ], "failure_modes": [ "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading" ], "pitfalls": [ "At a 40 mm bore, check shaft shoulder runout before fitting 51208; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 512xx medium-light section at 40 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 68 mm OD and 19 mm height.", "Thrust ball bearings carry axial load only — never apply radial load to 51208; the flat washers will skid and score.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51208 thrust ball bearing?", "a": "A 51208 thrust ball bearing has a 40 mm bore, 68 mm outside diameter and 19 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51208 bore code work?", "a": "The last two digits of 51208 are bore code 08, giving 08 × 5 = 40 mm bore. The 68 mm outside diameter and 19 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51208 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 40 mm bore?", "a": "The 512xx is the medium-light section: 68×19 mm, 14.0 mm radial section at 40 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51308", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 40, "D_mm": 78, "B_mm": 26, "seal_type": "open", "dynamic_load_kN": 69, "static_load_kN": 135, "fatigue_load_limit_kN": 6.05, "limiting_speed_rpm": 2200, "speed_oil_rpm": 3100, "weight_g": 548, "manufacturer_designation": "51308", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51308 carries bore code 08 = 40 mm. The ISO 104 boundary dimensions are 40 mm bore, 78 mm outside diameter and 26 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "gearbox axial load management", "conveyor drive thrust washers", "agricultural equipment spindle thrust", "industrial fan axial restraint" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "At a 40 mm bore, check shaft shoulder runout before fitting 51308; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 513xx medium section gains rating at 40 mm bore through a larger 78 mm OD and 26 mm height; the heavier assembly also trades away some speed versus a 512xx.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51308 thrust ball bearing?", "a": "A 51308 thrust ball bearing has a 40 mm bore, 78 mm outside diameter and 26 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51308 bore code work?", "a": "The last two digits of 51308 are bore code 08, giving 08 × 5 = 40 mm bore. The 78 mm outside diameter and 26 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51308 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 40 mm bore?", "a": "The 513xx is the medium section: 78×26 mm, 19.0 mm radial section at 40 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51409", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 100, "B_mm": 39, "seal_type": "open", "dynamic_load_kN": 130, "static_load_kN": 242, "fatigue_load_limit_kN": 10.9, "limiting_speed_rpm": 1600, "speed_oil_rpm": 2200, "weight_g": 1430, "manufacturer_designation": "51409", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51409 carries bore code 09 = 45 mm. The ISO 104 boundary dimensions are 45 mm bore, 100 mm outside diameter and 39 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "conveyor drive thrust washers", "agricultural equipment spindle thrust", "industrial fan axial restraint", "electric motor axial positioning" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "At a 45 mm bore, check shaft shoulder runout before fitting 51409; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 514xx heavy section at 45 mm bore (100 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure.", "The shaft washer (bore 45 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51409 thrust ball bearing?", "a": "A 51409 thrust ball bearing has a 45 mm bore, 100 mm outside diameter and 39 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51409 bore code work?", "a": "The last two digits of 51409 are bore code 09, giving 09 × 5 = 45 mm bore. The 100 mm outside diameter and 39 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51409 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 45 mm bore?", "a": "The 514xx is the heavy section: 100×39 mm, 27.5 mm radial section at 45 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51109", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 65, "B_mm": 14, "seal_type": "open", "dynamic_load_kN": 27.9, "static_load_kN": 69, "fatigue_load_limit_kN": 3.1, "limiting_speed_rpm": 3200, "speed_oil_rpm": 4600, "weight_g": 148, "manufacturer_designation": "51109", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51109 carries bore code 09 = 45 mm. The ISO 104 boundary dimensions are 45 mm bore, 65 mm outside diameter and 14 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "conveyor drive thrust washers", "agricultural equipment spindle thrust", "industrial fan axial restraint", "electric motor axial positioning" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 45 mm bore, check shaft shoulder runout before fitting 51109; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 511xx light section at 45 mm bore uses a smaller 65 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure.", "The 14 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51109." ], "faq": [ { "q": "What are the dimensions of a 51109 thrust ball bearing?", "a": "A 51109 thrust ball bearing has a 45 mm bore, 65 mm outside diameter and 14 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51109 bore code work?", "a": "The last two digits of 51109 are bore code 09, giving 09 × 5 = 45 mm bore. The 65 mm outside diameter and 14 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51109 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 45 mm bore?", "a": "The 511xx is the light section: 65×14 mm with a 10.0 mm radial section at 45 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51209", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 73, "B_mm": 20, "seal_type": "open", "dynamic_load_kN": 47.5, "static_load_kN": 105, "fatigue_load_limit_kN": 4.75, "limiting_speed_rpm": 2600, "speed_oil_rpm": 3700, "weight_g": 317, "manufacturer_designation": "51209", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51209 carries bore code 09 = 45 mm. The ISO 104 boundary dimensions are 45 mm bore, 73 mm outside diameter and 20 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "industrial fan axial restraint", "electric motor axial positioning", "pump and compressor thrust support", "gearbox axial load management" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At a 45 mm bore, check shaft shoulder runout before fitting 51209; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 512xx medium-light section at 45 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 73 mm OD and 20 mm height.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back.", "The shaft washer (bore 45 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51209 thrust ball bearing?", "a": "A 51209 thrust ball bearing has a 45 mm bore, 73 mm outside diameter and 20 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51209 bore code work?", "a": "The last two digits of 51209 are bore code 09, giving 09 × 5 = 45 mm bore. The 73 mm outside diameter and 20 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51209 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 45 mm bore?", "a": "The 512xx is the medium-light section: 73×20 mm, 14.0 mm radial section at 45 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51309", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 45, "D_mm": 85, "B_mm": 28, "seal_type": "open", "dynamic_load_kN": 80, "static_load_kN": 163, "fatigue_load_limit_kN": 7.35, "limiting_speed_rpm": 2000, "speed_oil_rpm": 2900, "weight_g": 684, "manufacturer_designation": "51309", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51309 carries bore code 09 = 45 mm. The ISO 104 boundary dimensions are 45 mm bore, 85 mm outside diameter and 28 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "pump and compressor thrust support", "gearbox axial load management", "conveyor drive thrust washers", "agricultural equipment spindle thrust" ], "failure_modes": [ "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading" ], "pitfalls": [ "At a 45 mm bore, check shaft shoulder runout before fitting 51309; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 513xx medium section gains rating at 45 mm bore through a larger 85 mm OD and 28 mm height; the heavier assembly also trades away some speed versus a 512xx.", "The shaft washer (bore 45 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment.", "The 28 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51309." ], "faq": [ { "q": "What are the dimensions of a 51309 thrust ball bearing?", "a": "A 51309 thrust ball bearing has a 45 mm bore, 85 mm outside diameter and 28 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51309 bore code work?", "a": "The last two digits of 51309 are bore code 09, giving 09 × 5 = 45 mm bore. The 85 mm outside diameter and 28 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51309 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 45 mm bore?", "a": "The 513xx is the medium section: 85×28 mm, 20.0 mm radial section at 45 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51410", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 110, "B_mm": 43, "seal_type": "open", "dynamic_load_kN": 159, "static_load_kN": 318, "fatigue_load_limit_kN": 14.2, "limiting_speed_rpm": 1400, "speed_oil_rpm": 2000, "weight_g": 1970, "manufacturer_designation": "51410", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51410 carries bore code 10 = 50 mm. The ISO 104 boundary dimensions are 50 mm bore, 110 mm outside diameter and 43 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "gearbox axial load management", "conveyor drive thrust washers", "agricultural equipment spindle thrust", "industrial fan axial restraint" ], "failure_modes": [ "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading" ], "pitfalls": [ "At a 50 mm bore, check shaft shoulder runout before fitting 51410; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 514xx heavy section at 50 mm bore (110 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "Thrust ball bearings carry axial load only — never apply radial load to 51410; the flat washers will skid and score." ], "faq": [ { "q": "What are the dimensions of a 51410 thrust ball bearing?", "a": "A 51410 thrust ball bearing has a 50 mm bore, 110 mm outside diameter and 43 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51410 bore code work?", "a": "The last two digits of 51410 are bore code 10, giving 10 × 5 = 50 mm bore. The 110 mm outside diameter and 43 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51410 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 50 mm bore?", "a": "The 514xx is the heavy section: 110×43 mm, 30.0 mm radial section at 50 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51110", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 70, "B_mm": 14, "seal_type": "open", "dynamic_load_kN": 28.8, "static_load_kN": 75.5, "fatigue_load_limit_kN": 3.4, "limiting_speed_rpm": 3100, "speed_oil_rpm": 4500, "weight_g": 161, "manufacturer_designation": "51110", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51110 carries bore code 10 = 50 mm. The ISO 104 boundary dimensions are 50 mm bore, 70 mm outside diameter and 14 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "gearbox axial load management", "conveyor drive thrust washers", "agricultural equipment spindle thrust", "industrial fan axial restraint" ], "failure_modes": [ "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force" ], "pitfalls": [ "At a 50 mm bore, check shaft shoulder runout before fitting 51110; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 511xx light section at 50 mm bore uses a smaller 70 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure." ], "faq": [ { "q": "What are the dimensions of a 51110 thrust ball bearing?", "a": "A 51110 thrust ball bearing has a 50 mm bore, 70 mm outside diameter and 14 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51110 bore code work?", "a": "The last two digits of 51110 are bore code 10, giving 10 × 5 = 50 mm bore. The 70 mm outside diameter and 14 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51110 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 50 mm bore?", "a": "The 511xx is the light section: 70×14 mm with a 10.0 mm radial section at 50 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51210", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 78, "B_mm": 22, "seal_type": "open", "dynamic_load_kN": 48.5, "static_load_kN": 111, "fatigue_load_limit_kN": 5.05, "limiting_speed_rpm": 2400, "speed_oil_rpm": 3400, "weight_g": 378, "manufacturer_designation": "51210", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51210 carries bore code 10 = 50 mm. The ISO 104 boundary dimensions are 50 mm bore, 78 mm outside diameter and 22 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "agricultural equipment spindle thrust", "industrial fan axial restraint", "electric motor axial positioning", "pump and compressor thrust support" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 50 mm bore, check shaft shoulder runout before fitting 51210; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 512xx medium-light section at 50 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 78 mm OD and 22 mm height.", "The 22 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51210.", "Thrust ball bearings carry axial load only — never apply radial load to 51210; the flat washers will skid and score." ], "faq": [ { "q": "What are the dimensions of a 51210 thrust ball bearing?", "a": "A 51210 thrust ball bearing has a 50 mm bore, 78 mm outside diameter and 22 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51210 bore code work?", "a": "The last two digits of 51210 are bore code 10, giving 10 × 5 = 50 mm bore. The 78 mm outside diameter and 22 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51210 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 50 mm bore?", "a": "The 512xx is the medium-light section: 78×22 mm, 14.0 mm radial section at 50 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51310", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 50, "D_mm": 95, "B_mm": 31, "seal_type": "open", "dynamic_load_kN": 96.5, "static_load_kN": 202, "fatigue_load_limit_kN": 9.1, "limiting_speed_rpm": 1800, "speed_oil_rpm": 2600, "weight_g": 951, "manufacturer_designation": "51310", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51310 carries bore code 10 = 50 mm. The ISO 104 boundary dimensions are 50 mm bore, 95 mm outside diameter and 31 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "electric motor axial positioning", "pump and compressor thrust support", "gearbox axial load management", "conveyor drive thrust washers" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At a 50 mm bore, check shaft shoulder runout before fitting 51310; a skewed shoulder tilts the shaft washer and concentrates load on a few balls.", "The 513xx medium section gains rating at 50 mm bore through a larger 95 mm OD and 31 mm height; the heavier assembly also trades away some speed versus a 512xx.", "Thrust ball bearings carry axial load only — never apply radial load to 51310; the flat washers will skid and score.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure." ], "faq": [ { "q": "What are the dimensions of a 51310 thrust ball bearing?", "a": "A 51310 thrust ball bearing has a 50 mm bore, 95 mm outside diameter and 31 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51310 bore code work?", "a": "The last two digits of 51310 are bore code 10, giving 10 × 5 = 50 mm bore. The 95 mm outside diameter and 31 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51310 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 50 mm bore?", "a": "The 513xx is the medium section: 95×31 mm, 22.5 mm radial section at 50 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51411", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 120, "B_mm": 48, "seal_type": "open", "dynamic_load_kN": 176, "static_load_kN": 395, "fatigue_load_limit_kN": 17.4, "limiting_speed_rpm": 1300, "speed_oil_rpm": 1800, "weight_g": 2720, "manufacturer_designation": "51411", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51411 carries bore code 11 = 55 mm. The ISO 104 boundary dimensions are 55 mm bore, 120 mm outside diameter and 48 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers", "machine tool spindle axial positioning" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At a 55 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 514xx heavy section at 55 mm bore (120 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "The shaft washer (bore 55 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51411 thrust ball bearing?", "a": "A 51411 thrust ball bearing has a 55 mm bore, 120 mm outside diameter and 48 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51411 bore code work?", "a": "The last two digits of 51411 are bore code 11, giving 11 × 5 = 55 mm bore. The 120 mm outside diameter and 48 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51411 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 55 mm bore?", "a": "The 514xx is the heavy section: 120×48 mm, 32.5 mm radial section at 55 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51111", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 78, "B_mm": 16, "seal_type": "open", "dynamic_load_kN": 35.5, "static_load_kN": 85, "fatigue_load_limit_kN": 3.8, "limiting_speed_rpm": 2800, "speed_oil_rpm": 4000, "weight_g": 247, "manufacturer_designation": "51111", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51111 carries bore code 11 = 55 mm. The ISO 104 boundary dimensions are 55 mm bore, 78 mm outside diameter and 16 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers", "machine tool spindle axial positioning" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "At a 55 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 511xx light section at 55 mm bore uses a smaller 78 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "The shaft washer (bore 55 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51111 thrust ball bearing?", "a": "A 51111 thrust ball bearing has a 55 mm bore, 78 mm outside diameter and 16 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51111 bore code work?", "a": "The last two digits of 51111 are bore code 11, giving 11 × 5 = 55 mm bore. The 78 mm outside diameter and 16 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51111 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 55 mm bore?", "a": "The 511xx is the light section: 78×16 mm with an 11.5 mm radial section at 55 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51211", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 90, "B_mm": 25, "seal_type": "open", "dynamic_load_kN": 69.5, "static_load_kN": 150, "fatigue_load_limit_kN": 6.3, "limiting_speed_rpm": 2200, "speed_oil_rpm": 3100, "weight_g": 590, "manufacturer_designation": "51211", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51211 carries bore code 11 = 55 mm. The ISO 104 boundary dimensions are 55 mm bore, 90 mm outside diameter and 25 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "conveyor and elevator thrust washers", "machine tool spindle axial positioning", "paper mill roll axial restraint", "industrial motor and generator thrust" ], "failure_modes": [ "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force" ], "pitfalls": [ "At a 55 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 512xx medium-light section at 55 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 90 mm OD and 25 mm height.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51211 thrust ball bearing?", "a": "A 51211 thrust ball bearing has a 55 mm bore, 90 mm outside diameter and 25 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51211 bore code work?", "a": "The last two digits of 51211 are bore code 11, giving 11 × 5 = 55 mm bore. The 90 mm outside diameter and 25 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51211 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 55 mm bore?", "a": "The 512xx is the medium-light section: 90×25 mm, 17.5 mm radial section at 55 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51311", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 55, "D_mm": 105, "B_mm": 35, "seal_type": "open", "dynamic_load_kN": 119, "static_load_kN": 246, "fatigue_load_limit_kN": 11.1, "limiting_speed_rpm": 1600, "speed_oil_rpm": 2300, "weight_g": 1290, "manufacturer_designation": "51311", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51311 carries bore code 11 = 55 mm. The ISO 104 boundary dimensions are 55 mm bore, 105 mm outside diameter and 35 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "paper mill roll axial restraint", "industrial motor and generator thrust", "heavy pump axial load support", "gearbox and reducer thrust management" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 55 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 513xx medium section gains rating at 55 mm bore through a larger 105 mm OD and 35 mm height; the heavier assembly also trades away some speed versus a 512xx.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51311 thrust ball bearing?", "a": "A 51311 thrust ball bearing has a 55 mm bore, 105 mm outside diameter and 35 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51311 bore code work?", "a": "The last two digits of 51311 are bore code 11, giving 11 × 5 = 55 mm bore. The 105 mm outside diameter and 35 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51311 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 55 mm bore?", "a": "The 513xx is the medium section: 105×35 mm, 25.0 mm radial section at 55 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51412", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 130, "B_mm": 51, "seal_type": "open", "dynamic_load_kN": 222, "static_load_kN": 475, "fatigue_load_limit_kN": 19.9, "limiting_speed_rpm": 1100, "speed_oil_rpm": 1600, "weight_g": 3490, "manufacturer_designation": "51412", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51412 carries bore code 12 = 60 mm. The ISO 104 boundary dimensions are 60 mm bore, 130 mm outside diameter and 51 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "industrial motor and generator thrust", "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 60 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 514xx heavy section at 60 mm bore (130 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "Thrust ball bearings carry axial load only — never apply radial load to 51412; the flat washers will skid and score.", "The 51 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51412." ], "faq": [ { "q": "What are the dimensions of a 51412 thrust ball bearing?", "a": "A 51412 thrust ball bearing has a 60 mm bore, 130 mm outside diameter and 51 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51412 bore code work?", "a": "The last two digits of 51412 are bore code 12, giving 12 × 5 = 60 mm bore. The 130 mm outside diameter and 51 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51412 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 60 mm bore?", "a": "The 514xx is the heavy section: 130×51 mm, 35.0 mm radial section at 60 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51112", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 85, "B_mm": 17, "seal_type": "open", "dynamic_load_kN": 41.5, "static_load_kN": 113, "fatigue_load_limit_kN": 5.1, "limiting_speed_rpm": 2600, "speed_oil_rpm": 3700, "weight_g": 296, "manufacturer_designation": "51112", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51112 carries bore code 12 = 60 mm. The ISO 104 boundary dimensions are 60 mm bore, 85 mm outside diameter and 17 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "industrial motor and generator thrust", "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "At a 60 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 511xx light section at 60 mm bore uses a smaller 85 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Thrust ball bearings carry axial load only — never apply radial load to 51112; the flat washers will skid and score.", "The shaft washer (bore 60 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51112 thrust ball bearing?", "a": "A 51112 thrust ball bearing has a 60 mm bore, 85 mm outside diameter and 17 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51112 bore code work?", "a": "The last two digits of 51112 are bore code 12, giving 12 × 5 = 60 mm bore. The 85 mm outside diameter and 17 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51112 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 60 mm bore?", "a": "The 511xx is the light section: 85×17 mm with a 12.5 mm radial section at 60 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51212", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 95, "B_mm": 26, "seal_type": "open", "dynamic_load_kN": 73.5, "static_load_kN": 153, "fatigue_load_limit_kN": 8.35, "limiting_speed_rpm": 2000, "speed_oil_rpm": 2800, "weight_g": 676, "manufacturer_designation": "51212", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51212 carries bore code 12 = 60 mm. The ISO 104 boundary dimensions are 60 mm bore, 95 mm outside diameter and 26 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "gearbox and reducer thrust management", "conveyor and elevator thrust washers", "machine tool spindle axial positioning", "paper mill roll axial restraint" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "At a 60 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 512xx medium-light section at 60 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 95 mm OD and 26 mm height.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "The 26 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51212." ], "faq": [ { "q": "What are the dimensions of a 51212 thrust ball bearing?", "a": "A 51212 thrust ball bearing has a 60 mm bore, 95 mm outside diameter and 26 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51212 bore code work?", "a": "The last two digits of 51212 are bore code 12, giving 12 × 5 = 60 mm bore. The 95 mm outside diameter and 26 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51212 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 60 mm bore?", "a": "The 512xx is the medium-light section: 95×26 mm, 17.5 mm radial section at 60 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51312", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 60, "D_mm": 110, "B_mm": 35, "seal_type": "open", "dynamic_load_kN": 125, "static_load_kN": 268, "fatigue_load_limit_kN": 12.1, "limiting_speed_rpm": 1500, "speed_oil_rpm": 2200, "weight_g": 1470, "manufacturer_designation": "51312", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51312 carries bore code 12 = 60 mm. The ISO 104 boundary dimensions are 60 mm bore, 110 mm outside diameter and 35 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "machine tool spindle axial positioning", "paper mill roll axial restraint", "industrial motor and generator thrust", "heavy pump axial load support" ], "failure_modes": [ "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force" ], "pitfalls": [ "At a 60 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 513xx medium section gains rating at 60 mm bore through a larger 110 mm OD and 35 mm height; the heavier assembly also trades away some speed versus a 512xx.", "The 35 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51312.", "The shaft washer (bore 60 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51312 thrust ball bearing?", "a": "A 51312 thrust ball bearing has a 60 mm bore, 110 mm outside diameter and 35 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51312 bore code work?", "a": "The last two digits of 51312 are bore code 12, giving 12 × 5 = 60 mm bore. The 110 mm outside diameter and 35 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51312 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 60 mm bore?", "a": "The 513xx is the medium section: 110×35 mm, 25.0 mm radial section at 60 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51413", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 140, "B_mm": 56, "seal_type": "open", "dynamic_load_kN": 255, "static_load_kN": 555, "fatigue_load_limit_kN": 23.2, "limiting_speed_rpm": 1000, "speed_oil_rpm": 1500, "weight_g": 4470, "manufacturer_designation": "51413", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51413 carries bore code 13 = 65 mm. The ISO 104 boundary dimensions are 65 mm bore, 140 mm outside diameter and 56 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "paper mill roll axial restraint", "industrial motor and generator thrust", "heavy pump axial load support", "gearbox and reducer thrust management" ], "failure_modes": [ "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force" ], "pitfalls": [ "At a 65 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 514xx heavy section at 65 mm bore (140 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure." ], "faq": [ { "q": "What are the dimensions of a 51413 thrust ball bearing?", "a": "A 51413 thrust ball bearing has a 65 mm bore, 140 mm outside diameter and 56 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51413 bore code work?", "a": "The last two digits of 51413 are bore code 13, giving 13 × 5 = 65 mm bore. The 140 mm outside diameter and 56 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51413 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 65 mm bore?", "a": "The 514xx is the heavy section: 140×56 mm, 37.5 mm radial section at 65 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51113", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 90, "B_mm": 18, "seal_type": "open", "dynamic_load_kN": 44, "static_load_kN": 122, "fatigue_load_limit_kN": 5.6, "limiting_speed_rpm": 2400, "speed_oil_rpm": 3500, "weight_g": 350, "manufacturer_designation": "51113", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51113 carries bore code 13 = 65 mm. The ISO 104 boundary dimensions are 65 mm bore, 90 mm outside diameter and 18 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "paper mill roll axial restraint", "industrial motor and generator thrust", "heavy pump axial load support", "gearbox and reducer thrust management" ], "failure_modes": [ "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading" ], "pitfalls": [ "At a 65 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 511xx light section at 65 mm bore uses a smaller 90 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back.", "Thrust ball bearings carry axial load only — never apply radial load to 51113; the flat washers will skid and score." ], "faq": [ { "q": "What are the dimensions of a 51113 thrust ball bearing?", "a": "A 51113 thrust ball bearing has a 65 mm bore, 90 mm outside diameter and 18 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51113 bore code work?", "a": "The last two digits of 51113 are bore code 13, giving 13 × 5 = 65 mm bore. The 90 mm outside diameter and 18 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51113 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 65 mm bore?", "a": "The 511xx is the light section: 90×18 mm with a 12.5 mm radial section at 65 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51213", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 100, "B_mm": 27, "seal_type": "open", "dynamic_load_kN": 75.5, "static_load_kN": 168, "fatigue_load_limit_kN": 9.2, "limiting_speed_rpm": 1900, "speed_oil_rpm": 2700, "weight_g": 780, "manufacturer_designation": "51213", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51213 carries bore code 13 = 65 mm. The ISO 104 boundary dimensions are 65 mm bore, 100 mm outside diameter and 27 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers", "machine tool spindle axial positioning" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "At a 65 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 512xx medium-light section at 65 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 100 mm OD and 27 mm height.", "The shaft washer (bore 65 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure." ], "faq": [ { "q": "What are the dimensions of a 51213 thrust ball bearing?", "a": "A 51213 thrust ball bearing has a 65 mm bore, 100 mm outside diameter and 27 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51213 bore code work?", "a": "The last two digits of 51213 are bore code 13, giving 13 × 5 = 65 mm bore. The 100 mm outside diameter and 27 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51213 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 65 mm bore?", "a": "The 512xx is the medium-light section: 100×27 mm, 17.5 mm radial section at 65 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51313", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 65, "D_mm": 115, "B_mm": 36, "seal_type": "open", "dynamic_load_kN": 132, "static_load_kN": 280, "fatigue_load_limit_kN": 13, "limiting_speed_rpm": 1400, "speed_oil_rpm": 2000, "weight_g": 1720, "manufacturer_designation": "51313", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51313 carries bore code 13 = 65 mm. The ISO 104 boundary dimensions are 65 mm bore, 115 mm outside diameter and 36 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "conveyor and elevator thrust washers", "machine tool spindle axial positioning", "paper mill roll axial restraint", "industrial motor and generator thrust" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "At a 65 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 513xx medium section gains rating at 65 mm bore through a larger 115 mm OD and 36 mm height; the heavier assembly also trades away some speed versus a 512xx.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure.", "Thrust ball bearings carry axial load only — never apply radial load to 51313; the flat washers will skid and score." ], "faq": [ { "q": "What are the dimensions of a 51313 thrust ball bearing?", "a": "A 51313 thrust ball bearing has a 65 mm bore, 115 mm outside diameter and 36 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51313 bore code work?", "a": "The last two digits of 51313 are bore code 13, giving 13 × 5 = 65 mm bore. The 115 mm outside diameter and 36 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51313 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 65 mm bore?", "a": "The 513xx is the medium section: 115×36 mm, 25.0 mm radial section at 65 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51414", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 150, "B_mm": 60, "seal_type": "open", "dynamic_load_kN": 285, "static_load_kN": 630, "fatigue_load_limit_kN": 26.2, "limiting_speed_rpm": 940, "speed_oil_rpm": 1400, "weight_g": 5480, "manufacturer_designation": "51414", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51414 carries bore code 14 = 70 mm. The ISO 104 boundary dimensions are 70 mm bore, 150 mm outside diameter and 60 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "machine tool spindle axial positioning", "paper mill roll axial restraint", "industrial motor and generator thrust", "heavy pump axial load support" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "At a 70 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 514xx heavy section at 70 mm bore (150 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "The 60 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51414.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51414 thrust ball bearing?", "a": "A 51414 thrust ball bearing has a 70 mm bore, 150 mm outside diameter and 60 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51414 bore code work?", "a": "The last two digits of 51414 are bore code 14, giving 14 × 5 = 70 mm bore. The 150 mm outside diameter and 60 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51414 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 70 mm bore?", "a": "The 514xx is the heavy section: 150×60 mm, 40.0 mm radial section at 70 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51114", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 95, "B_mm": 18, "seal_type": "open", "dynamic_load_kN": 45, "static_load_kN": 134, "fatigue_load_limit_kN": 6.2, "limiting_speed_rpm": 2300, "speed_oil_rpm": 3200, "weight_g": 370, "manufacturer_designation": "51114", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51114 carries bore code 14 = 70 mm. The ISO 104 boundary dimensions are 70 mm bore, 95 mm outside diameter and 18 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "machine tool spindle axial positioning", "paper mill roll axial restraint", "industrial motor and generator thrust", "heavy pump axial load support" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At a 70 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 511xx light section at 70 mm bore uses a smaller 95 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "The 18 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51114.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51114 thrust ball bearing?", "a": "A 51114 thrust ball bearing has a 70 mm bore, 95 mm outside diameter and 18 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51114 bore code work?", "a": "The last two digits of 51114 are bore code 14, giving 14 × 5 = 70 mm bore. The 95 mm outside diameter and 18 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51114 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 70 mm bore?", "a": "The 511xx is the light section: 95×18 mm with a 12.5 mm radial section at 70 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51214", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 105, "B_mm": 27, "seal_type": "open", "dynamic_load_kN": 80, "static_load_kN": 185, "fatigue_load_limit_kN": 10.2, "limiting_speed_rpm": 1800, "speed_oil_rpm": 2500, "weight_g": 840, "manufacturer_designation": "51214", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51214 carries bore code 14 = 70 mm. The ISO 104 boundary dimensions are 70 mm bore, 105 mm outside diameter and 27 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "industrial motor and generator thrust", "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers" ], "failure_modes": [ "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading" ], "pitfalls": [ "At a 70 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 512xx medium-light section at 70 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 105 mm OD and 27 mm height.", "Thrust ball bearings carry axial load only — never apply radial load to 51214; the flat washers will skid and score.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51214 thrust ball bearing?", "a": "A 51214 thrust ball bearing has a 70 mm bore, 105 mm outside diameter and 27 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51214 bore code work?", "a": "The last two digits of 51214 are bore code 14, giving 14 × 5 = 70 mm bore. The 105 mm outside diameter and 27 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51214 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 70 mm bore?", "a": "The 512xx is the medium-light section: 105×27 mm, 17.5 mm radial section at 70 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51314", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 70, "D_mm": 125, "B_mm": 40, "seal_type": "open", "dynamic_load_kN": 160, "static_load_kN": 325, "fatigue_load_limit_kN": 15.2, "limiting_speed_rpm": 1300, "speed_oil_rpm": 1800, "weight_g": 2330, "manufacturer_designation": "51314", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51314 carries bore code 14 = 70 mm. The ISO 104 boundary dimensions are 70 mm bore, 125 mm outside diameter and 40 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "gearbox and reducer thrust management", "conveyor and elevator thrust washers", "machine tool spindle axial positioning", "paper mill roll axial restraint" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "At a 70 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 513xx medium section gains rating at 70 mm bore through a larger 125 mm OD and 40 mm height; the heavier assembly also trades away some speed versus a 512xx.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51314 thrust ball bearing?", "a": "A 51314 thrust ball bearing has a 70 mm bore, 125 mm outside diameter and 40 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51314 bore code work?", "a": "The last two digits of 51314 are bore code 14, giving 14 × 5 = 70 mm bore. The 125 mm outside diameter and 40 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51314 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 70 mm bore?", "a": "The 513xx is the medium section: 125×40 mm, 27.5 mm radial section at 70 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51415", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 160, "B_mm": 65, "seal_type": "open", "dynamic_load_kN": 325, "static_load_kN": 750, "fatigue_load_limit_kN": 31, "limiting_speed_rpm": 890, "speed_oil_rpm": 1300, "weight_g": 7770, "manufacturer_designation": "51415", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51415 carries bore code 15 = 75 mm. The ISO 104 boundary dimensions are 75 mm bore, 160 mm outside diameter and 65 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "conveyor and elevator thrust washers", "machine tool spindle axial positioning", "paper mill roll axial restraint", "industrial motor and generator thrust" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "At a 75 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 514xx heavy section at 75 mm bore (160 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure.", "The shaft washer (bore 75 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51415 thrust ball bearing?", "a": "A 51415 thrust ball bearing has a 75 mm bore, 160 mm outside diameter and 65 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51415 bore code work?", "a": "The last two digits of 51415 are bore code 15, giving 15 × 5 = 75 mm bore. The 160 mm outside diameter and 65 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51415 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 75 mm bore?", "a": "The 514xx is the heavy section: 160×65 mm, 42.5 mm radial section at 75 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51115", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 100, "B_mm": 19, "seal_type": "open", "dynamic_load_kN": 46, "static_load_kN": 140, "fatigue_load_limit_kN": 6.45, "limiting_speed_rpm": 2200, "speed_oil_rpm": 3100, "weight_g": 400, "manufacturer_designation": "51115", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51115 carries bore code 15 = 75 mm. The ISO 104 boundary dimensions are 75 mm bore, 100 mm outside diameter and 19 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "conveyor and elevator thrust washers", "machine tool spindle axial positioning", "paper mill roll axial restraint", "industrial motor and generator thrust" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 75 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 511xx light section at 75 mm bore uses a smaller 100 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure.", "The 19 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51115." ], "faq": [ { "q": "What are the dimensions of a 51115 thrust ball bearing?", "a": "A 51115 thrust ball bearing has a 75 mm bore, 100 mm outside diameter and 19 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51115 bore code work?", "a": "The last two digits of 51115 are bore code 15, giving 15 × 5 = 75 mm bore. The 100 mm outside diameter and 19 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51115 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 75 mm bore?", "a": "The 511xx is the light section: 100×19 mm with a 12.5 mm radial section at 75 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51215", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 110, "B_mm": 27, "seal_type": "open", "dynamic_load_kN": 80.5, "static_load_kN": 190, "fatigue_load_limit_kN": 10.6, "limiting_speed_rpm": 1700, "speed_oil_rpm": 2400, "weight_g": 920, "manufacturer_designation": "51215", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51215 carries bore code 15 = 75 mm. The ISO 104 boundary dimensions are 75 mm bore, 110 mm outside diameter and 27 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "paper mill roll axial restraint", "industrial motor and generator thrust", "heavy pump axial load support", "gearbox and reducer thrust management" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At a 75 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 512xx medium-light section at 75 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 110 mm OD and 27 mm height.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back.", "The shaft washer (bore 75 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51215 thrust ball bearing?", "a": "A 51215 thrust ball bearing has a 75 mm bore, 110 mm outside diameter and 27 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51215 bore code work?", "a": "The last two digits of 51215 are bore code 15, giving 15 × 5 = 75 mm bore. The 110 mm outside diameter and 27 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51215 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 75 mm bore?", "a": "The 512xx is the medium-light section: 110×27 mm, 17.5 mm radial section at 75 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51315", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 75, "D_mm": 135, "B_mm": 44, "seal_type": "open", "dynamic_load_kN": 171, "static_load_kN": 395, "fatigue_load_limit_kN": 17.4, "limiting_speed_rpm": 1300, "speed_oil_rpm": 1800, "weight_g": 2610, "manufacturer_designation": "51315", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51315 carries bore code 15 = 75 mm. The ISO 104 boundary dimensions are 75 mm bore, 135 mm outside diameter and 44 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers", "machine tool spindle axial positioning" ], "failure_modes": [ "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading" ], "pitfalls": [ "At a 75 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 513xx medium section gains rating at 75 mm bore through a larger 135 mm OD and 44 mm height; the heavier assembly also trades away some speed versus a 512xx.", "The shaft washer (bore 75 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment.", "The 44 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51315." ], "faq": [ { "q": "What are the dimensions of a 51315 thrust ball bearing?", "a": "A 51315 thrust ball bearing has a 75 mm bore, 135 mm outside diameter and 44 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51315 bore code work?", "a": "The last two digits of 51315 are bore code 15, giving 15 × 5 = 75 mm bore. The 135 mm outside diameter and 44 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51315 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 75 mm bore?", "a": "The 513xx is the medium section: 135×44 mm, 30.0 mm radial section at 75 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51416", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 80, "D_mm": 170, "B_mm": 68, "seal_type": "open", "dynamic_load_kN": 270, "static_load_kN": 620, "fatigue_load_limit_kN": 25, "limiting_speed_rpm": 890, "speed_oil_rpm": 1300, "weight_g": 7770, "manufacturer_designation": "51416", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51416 carries bore code 16 = 80 mm. The ISO 104 boundary dimensions are 80 mm bore, 170 mm outside diameter and 68 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "gearbox and reducer thrust management", "conveyor and elevator thrust washers", "machine tool spindle axial positioning", "paper mill roll axial restraint" ], "failure_modes": [ "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading" ], "pitfalls": [ "At a 80 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 514xx heavy section at 80 mm bore (170 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "Thrust ball bearings carry axial load only — never apply radial load to 51416; the flat washers will skid and score." ], "faq": [ { "q": "What are the dimensions of a 51416 thrust ball bearing?", "a": "A 51416 thrust ball bearing has a 80 mm bore, 170 mm outside diameter and 68 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51416 bore code work?", "a": "The last two digits of 51416 are bore code 16, giving 16 × 5 = 80 mm bore. The 170 mm outside diameter and 68 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51416 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 80 mm bore?", "a": "The 514xx is the heavy section: 170×68 mm, 45.0 mm radial section at 80 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51116", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 80, "D_mm": 105, "B_mm": 19, "seal_type": "open", "dynamic_load_kN": 46.5, "static_load_kN": 150, "fatigue_load_limit_kN": 6.8, "limiting_speed_rpm": 2100, "speed_oil_rpm": 3000, "weight_g": 422, "manufacturer_designation": "51116", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51116 carries bore code 16 = 80 mm. The ISO 104 boundary dimensions are 80 mm bore, 105 mm outside diameter and 19 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "gearbox and reducer thrust management", "conveyor and elevator thrust washers", "machine tool spindle axial positioning", "paper mill roll axial restraint" ], "failure_modes": [ "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force" ], "pitfalls": [ "At a 80 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 511xx light section at 80 mm bore uses a smaller 105 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure." ], "faq": [ { "q": "What are the dimensions of a 51116 thrust ball bearing?", "a": "A 51116 thrust ball bearing has a 80 mm bore, 105 mm outside diameter and 19 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51116 bore code work?", "a": "The last two digits of 51116 are bore code 16, giving 16 × 5 = 80 mm bore. The 105 mm outside diameter and 19 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51116 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 80 mm bore?", "a": "The 511xx is the light section: 105×19 mm with a 12.5 mm radial section at 80 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51216", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 80, "D_mm": 115, "B_mm": 28, "seal_type": "open", "dynamic_load_kN": 95.5, "static_load_kN": 264, "fatigue_load_limit_kN": 13.9, "limiting_speed_rpm": 1600, "speed_oil_rpm": 2200, "weight_g": 1250, "manufacturer_designation": "51216", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51216 carries bore code 16 = 80 mm. The ISO 104 boundary dimensions are 80 mm bore, 115 mm outside diameter and 28 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "machine tool spindle axial positioning", "paper mill roll axial restraint", "industrial motor and generator thrust", "heavy pump axial load support" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 80 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 512xx medium-light section at 80 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 115 mm OD and 28 mm height.", "The 28 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51216.", "Thrust ball bearings carry axial load only — never apply radial load to 51216; the flat washers will skid and score." ], "faq": [ { "q": "What are the dimensions of a 51216 thrust ball bearing?", "a": "A 51216 thrust ball bearing has a 80 mm bore, 115 mm outside diameter and 28 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51216 bore code work?", "a": "The last two digits of 51216 are bore code 16, giving 16 × 5 = 80 mm bore. The 115 mm outside diameter and 28 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51216 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 80 mm bore?", "a": "The 512xx is the medium-light section: 115×28 mm, 17.5 mm radial section at 80 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51316", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 80, "D_mm": 140, "B_mm": 44, "seal_type": "open", "dynamic_load_kN": 176, "static_load_kN": 425, "fatigue_load_limit_kN": 18.2, "limiting_speed_rpm": 1200, "speed_oil_rpm": 1600, "weight_g": 2720, "manufacturer_designation": "51316", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51316 carries bore code 16 = 80 mm. The ISO 104 boundary dimensions are 80 mm bore, 140 mm outside diameter and 44 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "industrial motor and generator thrust", "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At a 80 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 513xx medium section gains rating at 80 mm bore through a larger 140 mm OD and 44 mm height; the heavier assembly also trades away some speed versus a 512xx.", "Thrust ball bearings carry axial load only — never apply radial load to 51316; the flat washers will skid and score.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure." ], "faq": [ { "q": "What are the dimensions of a 51316 thrust ball bearing?", "a": "A 51316 thrust ball bearing has a 80 mm bore, 140 mm outside diameter and 44 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51316 bore code work?", "a": "The last two digits of 51316 are bore code 16, giving 16 × 5 = 80 mm bore. The 140 mm outside diameter and 44 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51316 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 80 mm bore?", "a": "The 513xx is the medium section: 140×44 mm, 30.0 mm radial section at 80 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51417", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 180, "B_mm": 72, "seal_type": "open", "dynamic_load_kN": 288, "static_load_kN": 685, "fatigue_load_limit_kN": 26.8, "limiting_speed_rpm": 840, "speed_oil_rpm": 1200, "weight_g": 9170, "manufacturer_designation": "51417", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51417 carries bore code 17 = 85 mm. The ISO 104 boundary dimensions are 85 mm bore, 180 mm outside diameter and 72 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers", "machine tool spindle axial positioning" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "At a 85 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 514xx heavy section at 85 mm bore (180 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "The shaft washer (bore 85 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51417 thrust ball bearing?", "a": "A 51417 thrust ball bearing has a 85 mm bore, 180 mm outside diameter and 72 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51417 bore code work?", "a": "The last two digits of 51417 are bore code 17, giving 17 × 5 = 85 mm bore. The 180 mm outside diameter and 72 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51417 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 85 mm bore?", "a": "The 514xx is the heavy section: 180×72 mm, 47.5 mm radial section at 85 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51117", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 110, "B_mm": 19, "seal_type": "open", "dynamic_load_kN": 59.5, "static_load_kN": 190, "fatigue_load_limit_kN": 8.35, "limiting_speed_rpm": 1900, "speed_oil_rpm": 2700, "weight_g": 444, "manufacturer_designation": "51117", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51117 carries bore code 17 = 85 mm. The ISO 104 boundary dimensions are 85 mm bore, 110 mm outside diameter and 19 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers", "machine tool spindle axial positioning" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "At a 85 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 511xx light section at 85 mm bore uses a smaller 110 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "The shaft washer (bore 85 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51117 thrust ball bearing?", "a": "A 51117 thrust ball bearing has a 85 mm bore, 110 mm outside diameter and 19 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51117 bore code work?", "a": "The last two digits of 51117 are bore code 17, giving 17 × 5 = 85 mm bore. The 110 mm outside diameter and 19 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51117 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 85 mm bore?", "a": "The 511xx is the light section: 110×19 mm with a 12.5 mm radial section at 85 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51217", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 125, "B_mm": 31, "seal_type": "open", "dynamic_load_kN": 117, "static_load_kN": 325, "fatigue_load_limit_kN": 13.9, "limiting_speed_rpm": 1400, "speed_oil_rpm": 2000, "weight_g": 1700, "manufacturer_designation": "51217", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51217 carries bore code 17 = 85 mm. The ISO 104 boundary dimensions are 85 mm bore, 125 mm outside diameter and 31 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "conveyor and elevator thrust washers", "machine tool spindle axial positioning", "paper mill roll axial restraint", "industrial motor and generator thrust" ], "failure_modes": [ "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force" ], "pitfalls": [ "At a 85 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 512xx medium-light section at 85 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 125 mm OD and 31 mm height.", "Minimum axial load is required to prevent ball skidding: at very light loads the balls slide rather than roll, causing smearing and early failure.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51217 thrust ball bearing?", "a": "A 51217 thrust ball bearing has a 85 mm bore, 125 mm outside diameter and 31 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51217 bore code work?", "a": "The last two digits of 51217 are bore code 17, giving 17 × 5 = 85 mm bore. The 125 mm outside diameter and 31 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51217 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 85 mm bore?", "a": "The 512xx is the medium-light section: 125×31 mm, 20.0 mm radial section at 85 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51317", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 85, "D_mm": 150, "B_mm": 49, "seal_type": "open", "dynamic_load_kN": 206, "static_load_kN": 490, "fatigue_load_limit_kN": 20.3, "limiting_speed_rpm": 1100, "speed_oil_rpm": 1600, "weight_g": 3520, "manufacturer_designation": "51317", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51317 carries bore code 17 = 85 mm. The ISO 104 boundary dimensions are 85 mm bore, 150 mm outside diameter and 49 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "paper mill roll axial restraint", "industrial motor and generator thrust", "heavy pump axial load support", "gearbox and reducer thrust management" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 85 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 513xx medium section gains rating at 85 mm bore through a larger 150 mm OD and 49 mm height; the heavier assembly also trades away some speed versus a 512xx.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51317 thrust ball bearing?", "a": "A 51317 thrust ball bearing has a 85 mm bore, 150 mm outside diameter and 49 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51317 bore code work?", "a": "The last two digits of 51317 are bore code 17, giving 17 × 5 = 85 mm bore. The 150 mm outside diameter and 49 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51317 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 85 mm bore?", "a": "The 513xx is the medium section: 150×49 mm, 32.5 mm radial section at 85 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51418", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 90, "D_mm": 190, "B_mm": 77, "seal_type": "open", "dynamic_load_kN": 305, "static_load_kN": 750, "fatigue_load_limit_kN": 28.6, "limiting_speed_rpm": 790, "speed_oil_rpm": 1100, "weight_g": 11000, "manufacturer_designation": "51418", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51418 carries bore code 18 = 90 mm. The ISO 104 boundary dimensions are 90 mm bore, 190 mm outside diameter and 77 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "industrial motor and generator thrust", "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers" ], "failure_modes": [ "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit" ], "pitfalls": [ "At a 90 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 514xx heavy section at 90 mm bore (190 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "Thrust ball bearings carry axial load only — never apply radial load to 51418; the flat washers will skid and score.", "The 77 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51418." ], "faq": [ { "q": "What are the dimensions of a 51418 thrust ball bearing?", "a": "A 51418 thrust ball bearing has a 90 mm bore, 190 mm outside diameter and 77 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51418 bore code work?", "a": "The last two digits of 51418 are bore code 18, giving 18 × 5 = 90 mm bore. The 190 mm outside diameter and 77 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51418 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 90 mm bore?", "a": "The 514xx is the heavy section: 190×77 mm, 50.0 mm radial section at 90 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51118", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 90, "D_mm": 120, "B_mm": 22, "seal_type": "open", "dynamic_load_kN": 59.5, "static_load_kN": 190, "fatigue_load_limit_kN": 8.35, "limiting_speed_rpm": 1900, "speed_oil_rpm": 2700, "weight_g": 687, "manufacturer_designation": "51118", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51118 carries bore code 18 = 90 mm. The ISO 104 boundary dimensions are 90 mm bore, 120 mm outside diameter and 22 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "industrial motor and generator thrust", "heavy pump axial load support", "gearbox and reducer thrust management", "conveyor and elevator thrust washers" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "At a 90 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 511xx light section at 90 mm bore uses a smaller 120 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "Thrust ball bearings carry axial load only — never apply radial load to 51118; the flat washers will skid and score.", "The shaft washer (bore 90 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51118 thrust ball bearing?", "a": "A 51118 thrust ball bearing has a 90 mm bore, 120 mm outside diameter and 22 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51118 bore code work?", "a": "The last two digits of 51118 are bore code 18, giving 18 × 5 = 90 mm bore. The 120 mm outside diameter and 22 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51118 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 90 mm bore?", "a": "The 511xx is the light section: 120×22 mm with a 15.0 mm radial section at 90 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51218", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 90, "D_mm": 135, "B_mm": 35, "seal_type": "open", "dynamic_load_kN": 125, "static_load_kN": 345, "fatigue_load_limit_kN": 14.7, "limiting_speed_rpm": 1300, "speed_oil_rpm": 1900, "weight_g": 2180, "manufacturer_designation": "51218", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51218 carries bore code 18 = 90 mm. The ISO 104 boundary dimensions are 90 mm bore, 135 mm outside diameter and 35 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "gearbox and reducer thrust management", "conveyor and elevator thrust washers", "machine tool spindle axial positioning", "paper mill roll axial restraint" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "At a 90 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 512xx medium-light section at 90 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 135 mm OD and 35 mm height.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "The 35 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51218." ], "faq": [ { "q": "What are the dimensions of a 51218 thrust ball bearing?", "a": "A 51218 thrust ball bearing has a 90 mm bore, 135 mm outside diameter and 35 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51218 bore code work?", "a": "The last two digits of 51218 are bore code 18, giving 18 × 5 = 90 mm bore. The 135 mm outside diameter and 35 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51218 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 90 mm bore?", "a": "The 512xx is the medium-light section: 135×35 mm, 22.5 mm radial section at 90 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51318", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 90, "D_mm": 155, "B_mm": 50, "seal_type": "open", "dynamic_load_kN": 213, "static_load_kN": 525, "fatigue_load_limit_kN": 21.3, "limiting_speed_rpm": 1100, "speed_oil_rpm": 1600, "weight_g": 3740, "manufacturer_designation": "51318", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51318 carries bore code 18 = 90 mm. The ISO 104 boundary dimensions are 90 mm bore, 155 mm outside diameter and 50 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "machine tool spindle axial positioning", "paper mill roll axial restraint", "industrial motor and generator thrust", "heavy pump axial load support" ], "failure_modes": [ "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up", "raceway indentation from static overload or improper mounting force" ], "pitfalls": [ "At a 90 mm bore, thermal expansion of the shaft can preload the thrust bearing; verify the housing washer has radial clearance to float and compensate.", "The 513xx medium section gains rating at 90 mm bore through a larger 155 mm OD and 50 mm height; the heavier assembly also trades away some speed versus a 512xx.", "The 50 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51318.", "The shaft washer (bore 90 mm) must be a tight fit on the shaft; the housing washer should be loose in the housing to allow self-alignment." ], "faq": [ { "q": "What are the dimensions of a 51318 thrust ball bearing?", "a": "A 51318 thrust ball bearing has a 90 mm bore, 155 mm outside diameter and 50 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51318 bore code work?", "a": "The last two digits of 51318 are bore code 18, giving 18 × 5 = 90 mm bore. The 155 mm outside diameter and 50 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51318 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 90 mm bore?", "a": "The 513xx is the medium section: 155×50 mm, 32.5 mm radial section at 90 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51420", "brand": "NTN", "series": "51400-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 210, "B_mm": 85, "seal_type": "open", "dynamic_load_kN": 370, "static_load_kN": 865, "fatigue_load_limit_kN": 35, "limiting_speed_rpm": 800, "speed_oil_rpm": 1100, "weight_g": 13000, "manufacturer_designation": "51420", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51400-series (ISO 104 dimension series) the leading digits 514 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51420 carries bore code 20 = 100 mm. The ISO 104 boundary dimensions are 100 mm bore, 210 mm outside diameter and 85 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "ship propeller shaft thrust support", "mining equipment axial positioning", "heavy industrial drive thrust support", "large gearbox axial load management" ], "failure_modes": [ "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary", "smearing or scoring from marginal lubrication at start-up" ], "pitfalls": [ "Mount this 100 mm bore thrust bearing by heating the shaft washer (induction heater, max 120 °C) — never drive it home through the housing washer or balls.", "The 514xx heavy section at 100 mm bore (210 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm application gives excess heat and short grease life — use 511/512 there.", "The 85 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51420.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51420 thrust ball bearing?", "a": "A 51420 thrust ball bearing has a 100 mm bore, 210 mm outside diameter and 85 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51420 bore code work?", "a": "The last two digits of 51420 are bore code 20, giving 20 × 5 = 100 mm bore. The 210 mm outside diameter and 85 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51420 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51400 compare with other thrust series at the same 100 mm bore?", "a": "The 514xx is the heavy section: 210×85 mm, 55.0 mm radial section at 100 mm bore — the highest-capacity single-direction thrust option here, aimed at lower-speed, high-load shafts." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51120", "brand": "NTN", "series": "51100-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 135, "B_mm": 25, "seal_type": "open", "dynamic_load_kN": 85, "static_load_kN": 230, "fatigue_load_limit_kN": 10, "limiting_speed_rpm": 1700, "speed_oil_rpm": 2400, "weight_g": 960, "manufacturer_designation": "51120", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51100-series (ISO 104 dimension series) the leading digits 511 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51120 carries bore code 20 = 100 mm. The ISO 104 boundary dimensions are 100 mm bore, 135 mm outside diameter and 25 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "ship propeller shaft thrust support", "mining equipment axial positioning", "heavy industrial drive thrust support", "large gearbox axial load management" ], "failure_modes": [ "raceway indentation from static overload or improper mounting force", "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Mount this 100 mm bore thrust bearing by heating the shaft washer (induction heater, max 120 °C) — never drive it home through the housing washer or balls.", "The 511xx light section at 100 mm bore uses a smaller 135 mm OD than a 512xx; load ratings are lower, so do not replace a failed 512-series bearing with a 511-series without re-rating the load.", "The 25 mm height includes both washers and the cage; verify the axial space in the housing before specifying 51120.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51120 thrust ball bearing?", "a": "A 51120 thrust ball bearing has a 100 mm bore, 135 mm outside diameter and 25 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51120 bore code work?", "a": "The last two digits of 51120 are bore code 20, giving 20 × 5 = 100 mm bore. The 135 mm outside diameter and 25 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51120 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51100 compare with other thrust series at the same 100 mm bore?", "a": "The 511xx is the light section: 135×25 mm with a 17.5 mm radial section at 100 mm bore — below 512/513/514 in load capacity, for light axial loads in compact spaces." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51220", "brand": "NTN", "series": "51200-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 150, "B_mm": 38, "seal_type": "open", "dynamic_load_kN": 147, "static_load_kN": 410, "fatigue_load_limit_kN": 17.4, "limiting_speed_rpm": 1200, "speed_oil_rpm": 1700, "weight_g": 3100, "manufacturer_designation": "51220", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51200-series (ISO 104 dimension series) the leading digits 512 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51220 carries bore code 20 = 100 mm. The ISO 104 boundary dimensions are 100 mm bore, 150 mm outside diameter and 38 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "heavy industrial drive thrust support", "large gearbox axial load management", "crane and hoist drum thrust washers", "steel mill roll axial restraint" ], "failure_modes": [ "washer seat fretting from a loose housing or shaft fit", "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading" ], "pitfalls": [ "Mount this 100 mm bore thrust bearing by heating the shaft washer (induction heater, max 120 °C) — never drive it home through the housing washer or balls.", "The 512xx medium-light section at 100 mm bore is the default general-purpose thrust bearing; before upgrading to a 513xx for extra capacity, confirm the housing accepts a 150 mm OD and 38 mm height.", "Thrust ball bearings carry axial load only — never apply radial load to 51220; the flat washers will skid and score.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component." ], "faq": [ { "q": "What are the dimensions of a 51220 thrust ball bearing?", "a": "A 51220 thrust ball bearing has a 100 mm bore, 150 mm outside diameter and 38 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51220 bore code work?", "a": "The last two digits of 51220 are bore code 20, giving 20 × 5 = 100 mm bore. The 150 mm outside diameter and 38 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51220 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51200 compare with other thrust series at the same 100 mm bore?", "a": "The 512xx is the medium-light section: 150×38 mm, 25.0 mm radial section at 100 mm bore. A 513xx on the same bore is larger and higher-rated; a 511xx is smaller and lower-rated." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" }, { "sku": "51320", "brand": "NTN", "series": "51300-series", "type": "thrust_ball", "d_mm": 100, "D_mm": 170, "B_mm": 55, "seal_type": "open", "dynamic_load_kN": 237, "static_load_kN": 595, "fatigue_load_limit_kN": 25, "limiting_speed_rpm": 990, "speed_oil_rpm": 1400, "weight_g": 4880, "manufacturer_designation": "51320", "standard": "ISO 104", "source_ref": "https://www.ntnglobal.com/", "catalog_ver": "CAT. No. 2203-3/E 2024", "extracted_at": "2026-09-25", "aliases": [], "naming_rule_text": "In the 51300-series (ISO 104 dimension series) the leading digits 513 mark a single-direction thrust ball bearing and the last two digits encode the bore: 51320 carries bore code 20 = 100 mm. The ISO 104 boundary dimensions are 100 mm bore, 170 mm outside diameter and 55 mm height. Two flat washers (shaft and housing) and a ball cage assembly allow the bearing to carry pure axial load in one direction while accommodating minor misalignment.", "applications": [ "crane and hoist drum thrust washers", "steel mill roll axial restraint", "ship propeller shaft thrust support", "mining equipment axial positioning" ], "failure_modes": [ "rolling-contact fatigue spalling after the rated L10 life is exceeded", "cage wear or fracture from sustained vibration or shock loading", "false brinelling from vibration while the shaft is stationary" ], "pitfalls": [ "Mount this 100 mm bore thrust bearing by heating the shaft washer (induction heater, max 120 °C) — never drive it home through the housing washer or balls.", "The 513xx medium section gains rating at 100 mm bore through a larger 170 mm OD and 55 mm height; the heavier assembly also trades away some speed versus a 512xx.", "Do not use a thrust ball bearing for combined radial-axial loads — pair it with a radial bearing (deep-groove or spherical roller) for the radial component.", "Single-direction thrust ball bearings carry load in one direction only; for bidirectional thrust use a double-direction bearing or two single-direction units back-to-back." ], "faq": [ { "q": "What are the dimensions of a 51320 thrust ball bearing?", "a": "A 51320 thrust ball bearing has a 100 mm bore, 170 mm outside diameter and 55 mm height, per ISO 104 boundary dimensions. It consists of a shaft washer, housing washer and ball cage assembly." }, { "q": "How does the 51320 bore code work?", "a": "The last two digits of 51320 are bore code 20, giving 20 × 5 = 100 mm bore. The 170 mm outside diameter and 55 mm height follow the ISO 104 dimension series, not the bore code alone." }, { "q": "Can a 51320 thrust ball bearing carry radial load?", "a": "No. Single-direction thrust ball bearings carry axial load only. Any radial component must be supported by a separate radial bearing (deep-groove, cylindrical roller or spherical roller)." }, { "q": "How does the 51300 compare with other thrust series at the same 100 mm bore?", "a": "The 513xx is the medium section: 170×55 mm, 35.0 mm radial section at 100 mm bore, carrying more load than a 512xx but needing a larger housing bore and giving up some speed." } ], "confidence_score": 0.7, "status": "published", "last_verified": "2026-09-25" } ]