32314CU bearing: complete specifications & equivalents
The 32314CU 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 | 300 kN |
| Basic static load rating C0 | 380 kN |
| Fatigue load limit Pu | 45 kN |
| Limiting speed (mechanical) | 2500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 4530 g |
| Manufacturer designation | NTN 32314CU |
| 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 |
|---|---|---|---|
| 32314CU | 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 32314CU model number is decoded
NTN supplies this 70 mm bore tapered roller position as 32314CU: one cone assembly, one cup, line-contact rollers and a steel cage, rated 300 kN basic dynamic and 380 kN static on the extra-heavy 32300 family. The last two digits 14 are the ISO bore code, ×5 = 70 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 54 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The rollers run with their large ends against the cone's integral guide rib; the rib/end-flange contact carries the thrust component and is the reason lubricant must reach the rib face of 32314CU, not only the raceway. Selection: C 300 kN against C0 380 kN gives a C0/C ratio of 1.27 for the 70 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. 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
- 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
- cone-raceway spalling at the large rib when preload is set too high for the lubricant film
- 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
- cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling
- 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 4530 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 3,300 r/min oil ceiling.
- Grease packs must leave free volume in the 54 mm-wide set; over-greasing a paired bearing churning at the 3,300 r/min oil-band speed raises temperature and destroys the preload setting.
- Minimum load matters at high speed: an unloaded 32314CU at a large fraction of 2,500 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.
- Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 70 mm shoulder geometry, because retrofitting flips the cups.
- The 300/380 kN ratings and 45 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32314CU (ISO 355 5GD); 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 32314CU?
32314CU 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 300 kN, C0 380 kN, Pu 45 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 4530 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 32314CU?
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 (32314CU); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 32314CU designation encode the 70 mm bore and what is 5GD?
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. 5GD 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 32314CU list two speeds, 2,500 and 3,300 r/min?
The lower figure, 2,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32314CU at 3,300 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 32314CU mean?
Suffix reading on 32314CU: U marks the reinforced/uprated internal design of the bare number, a separate order number with higher load capacity than the basic execution; the CA/CU/DU letter marks a contact-angle/internal-geometry variant of the same envelope — quote the exact suffix because axial/radial capacity split differs; 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.