32314U bearing: complete specifications & equivalents
The 32314U is a ISO 355 radial bearing sized 70 x 150 x 54 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 70 mm |
| Outer diameter D | 150 mm |
| Width B | 54 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 345 kN |
| Basic static load rating C0 | 405 kN |
| Fatigue load limit Pu | 48 kN |
| Limiting speed (mechanical) | 2600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 4440 g |
| Manufacturer designation | NTN 32314U |
| 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 | 2.756 in |
|---|---|
| Outer diameter D | 5.906 in |
| Width B | 2.126 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 40 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) | 12 of 30 |
| Bore above smallest 32300-series size | 50 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32314U | 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 32314U model number is decoded
NTN supplies this 70 mm bore tapered roller position as 32314U: one cone assembly, one cup, line-contact rollers and a steel cage, rated 345 kN basic dynamic and 405 kN static on the extra-heavy 32300 family. On the NTN nameplate the parts carry 4T plus the bare code, while 2203E orders 32314U by the metric ISO 355 number (ISO series abbreviation 2GD): 70 mm bore, 150 mm OD. The 40.0 mm radial section carries the roller complement across the 70–150 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 two speed columns differ by a factor of .74 (grease/limiting 2,600 vs oil 3,500 r/min); heat generation at the cone rib decides which lubrication a real 32314U arrangement can sustain. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 70 mm pair is misadjusted and the 54 mm T set will edge-load in service.
Typical equipment & failure modes
Common applications
- large agricultural and forestry machine axles
- heavy industrial gearboxes and crane travel drives
- rolling-mill auxiliary and pinion-stand shafts
- large conveyor and bucket-elevator pulleys
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
- cage damage from a mounting blow delivered through the roller complement instead of the ring face
- false brinelling on a stationary paired set exposed to external vibration
Selection pitfalls — read before you substitute
- Mount the 70 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 4440 g ring mass makes cocking during fitting a direct raceway-brinelling risk.
- The extra-heavy 32300 family at 70 mm bore (150×54 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,500 r/min oil ceiling.
- Grease packs must leave free volume in the 54 mm-wide set; over-greasing a paired bearing churning at the 3,500 r/min oil-band speed raises temperature and destroys the preload setting.
- The 40.0 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32314U or the ring will bottom out on the radius instead of the shoulder face.
- The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 32314U by size alone can deliver the wrong contact-angle execution for a pinion position.
- The 345/405 kN ratings and 48 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32314U (ISO 355 2GD); 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 32314U?
32314U is a metric 4T tapered roller bearing to ISO 355: 70 mm bore, 150 mm outside diameter and 54 mm assembled width T (2.756 × 5.906 × 2.126 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 345 kN, C0 405 kN, Pu 48 kN, grease limiting speed 2,600 r/min, oil speed 3,500 r/min, mass about 4440 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 32314U?
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 (32314U); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 32314U designation encode the 70 mm bore and what is 2GD?
last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table). The 150 mm OD and 54 mm assembled T follow the ISO 355 dimension-series plan. 2GD 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 32314U list two speeds, 2,600 and 3,500 r/min?
The lower figure, 2,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32314U at 3,500 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 32314U mean?
Suffix reading on 32314U: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; 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.