32312C bearing: complete specifications & equivalents
The 32312C is a ISO 355 radial bearing sized 60 x 130 x 48.5 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 | 130 mm |
| Width B | 48.5 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 237 kN |
| Basic static load rating C0 | 296 kN |
| Limiting speed (mechanical) | 2900 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 3070 g |
| Manufacturer designation | NTN 32312C |
| 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 & 32300-series range
| Bore d | 2.362 in |
|---|---|
| Outer diameter D | 5.118 in |
| Width B | 1.909 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 35 mm |
| Smallest bore in 32300-series | 20 mm |
| Largest outer diameter in 32300-series | 460 mm |
| Width range across 32300-series | 22.25–154 mm |
| Bore position in 32300-series (smallest first) | 10 of 30 |
| Bore above smallest 32300-series size | 40 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32312C | 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 32312C model number is decoded
32312C belongs to the NTN metric 4T tapered roller range (extra-heavy 32300 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. Digit by digit, the bare number identifies the extra-heavy 32300 family and a bore code resolving to 60 mm; 130 mm OD and 48.5 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. The 35.0 mm radial section carries the roller complement across the 60–130 mm envelope; section and contact angle differ between NTN metric families even at the same bore, so 302/322/323 are not drop-in swaps. The 4.0 kN-per-mm-bore capacity figure for 32312C summarises the 237 kN rating over 60 mm bore; use it to sanity-check an interchange candidate before swapping brands. Mount the 60 mm-bore cone on the shaft first (induction heat, max 120 °C), fit the cup square in its housing, then set preload or end play; never drive the cup home through the rollers of 32312C.
Typical equipment & failure modes
Common applications
- mineral-processing feeder and crusher auxiliaries
- marine winch and deck-machinery shafts
- paper-machine press-section rolls
- large agricultural and forestry machine axles
Known failure patterns
- cup creep and housing fretting when the specified outer-ring press fit is not achieved
- rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair
- preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play
- pressed-steel cage pocket wear from roller skid at light radial load and high speed
- false brinelling on a stationary paired set exposed to external vibration
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 3070 g ring mass makes cocking during fitting a direct raceway-brinelling risk.
- The extra-heavy 32300 family at 60 mm bore (130×48.5 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,900 r/min oil ceiling.
- Never fit the 60 mm cone by hammering the 130 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.
- Replacing one half of an adjusted pair without resetting end play negates the 48.5 mm T dimension logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
- The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32312C by size alone can deliver the wrong contact-angle execution for a pinion position.
- The 237/296 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32312C (ISO 355 5FD); 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 32312C?
32312C is a metric 4T tapered roller bearing to ISO 355: 60 mm bore, 130 mm outside diameter and 48.5 mm assembled width T (2.362 × 5.118 × 1.909 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 237 kN, C0 296 kN (2203E prints no Pu for this size), grease limiting speed 2,900 r/min, oil speed 3,900 r/min, mass about 3070 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 32312C?
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 (32312C); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 32312C designation encode the 60 mm bore and what is 5FD?
last two digits 12 are the ISO bore code, ×5 = 60 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 48.5 mm assembled T follow the ISO 355 dimension-series plan. 5FD is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark.
Why does 32312C list two speeds, 2,900 and 3,900 r/min?
The lower figure, 2,900 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32312C at 3,900 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 32312C mean?
Suffix reading on 32312C: 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.