32912XA bearing: complete specifications & equivalents
The 32912XA is a ISO 355 radial bearing sized 60 x 85 x 17 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 60 mm |
| Outer diameter D | 85 mm |
| Width B | 17 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 56.5 kN |
| Basic static load rating C0 | 83 kN |
| Fatigue load limit Pu | 10.1 kN |
| Limiting speed (mechanical) | 4000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 281 g |
| Manufacturer designation | NTN 32912XA |
| Standard | ISO 355 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203E |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.
Dimensions in inches & 32900-series range
| Bore d | 2.362 in |
|---|---|
| Outer diameter D | 3.346 in |
| Width B | 0.669 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 12.5 mm |
| Smallest bore in 32900-series | 35 mm |
| Largest outer diameter in 32900-series | 600 mm |
| Width range across 32900-series | 14–100 mm |
| Bore position in 32900-series (smallest first) | 6 of 37 |
| Bore above smallest 32900-series size | 25 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32912XA | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the 32912XA model number is decoded
32912XA belongs to the NTN metric 4T tapered roller range (extra-light thin-section 32900 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. The last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 17 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32912XA cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The 0.9 kN-per-mm-bore capacity figure for 32912XA summarises the 56.5 kN rating over 60 mm bore; use it to sanity-check an interchange candidate before swapping brands. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 60 mm pair is misadjusted and the 17 mm T set will edge-load in service.
Typical equipment & failure modes
Common applications
- heavy industrial gearboxes and crane travel drives
- rolling-mill auxiliary and pinion-stand shafts
- large conveyor and bucket-elevator pulleys
- mineral-processing feeder and crusher auxiliaries
Known failure patterns
- cup creep and housing fretting when the specified outer-ring press fit is not achieved
- preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play
- rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair
- pressed-steel cage pocket wear from roller skid at light radial load and high speed
- rolling-contact fatigue after the catalogue L10 life at the actual combined load
Selection pitfalls — read before you substitute
- Mount the 60 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 281 g ring mass makes cocking during fitting a direct raceway-brinelling risk.
- The thin 17 mm section of 32912XA is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 60 mm bore smears the roller ends against the rib.
- Open 32912XA units have no seals: a wheel-hub or gearbox application needs external sealing or the 4,000 r/min grease figure is meaningless once water reaches the cone rib.
- Replacing one half of an adjusted pair without resetting end play negates the 17 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
- Do not confuse T (17 mm assembled width of cone + cup) with the cone width when drawing spacers; an abutment sized to T instead of the ring width leaves the cup unseated.
- The 56.5/83 kN ratings and 10.1 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32912XA; internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 32912XA?
32912XA is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 85 mm outside diameter and 17 mm assembled width T (2.362 × 3.346 × 0.669 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 56.5 kN, C0 83 kN, Pu 10.1 kN, grease limiting speed 4,000 r/min, oil speed 5,300 r/min, mass about 281 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 32912XA?
4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32912XA); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 32912XA designation encode the 60 mm bore?
last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 85 mm OD and 17 mm assembled T follow the ISO 355 dimension-series plan.
Why does 32912XA list two speeds, 4,000 and 5,300 r/min?
The lower figure, 4,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32912XA at 5,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 32912XA mean?
Suffix reading on 32912XA: X marks the execution built to the ISO boundary-dimension section (interchangeable envelope, NTN internal geometry); the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203E on 2026-10-01. Read our editorial & correction policy.