32934XU bearing: complete specifications & equivalents
The 32934XU is a ISO 355 radial bearing sized 170 x 230 x 38 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 170 mm |
| Outer diameter D | 230 mm |
| Width B | 38 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 315 kN |
| Basic static load rating C0 | 560 kN |
| Fatigue load limit Pu | 55 kN |
| Limiting speed (mechanical) | 1400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 4400 g |
| Manufacturer designation | NTN 32934XU |
| 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 | 6.693 in |
|---|---|
| Outer diameter D | 9.055 in |
| Width B | 1.496 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 30 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) | 22 of 37 |
| Bore above smallest 32900-series size | 135 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32934XU | 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 32934XU model number is decoded
For a 170 mm shaft with a thrust component, NTN lists 32934XU, a metric 4T tapered roller bearing of 315 kN C and 560 kN C0 inside the 230 mm OD, 38 mm-wide assembled set. Digit by digit, the bare number identifies the extra-light thin-section 32900 family and a bore code resolving to 170 mm; 230 mm OD and 38 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. 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 32934XU, not only the raceway. Catalogue mass of the 32934XU set is 4400 g (0.173 lb cone + cup); abutment and shaft shoulder design must carry that mass square to the axis. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 170 mm pair is misadjusted and the 38 mm T set will edge-load in service.
Typical equipment & failure modes
Common applications
- rolling-mill roll-neck and gearbox positions
- large crusher and SAG/AG-mill drive shafts
- wind-turbine gearbox and main-shaft arrangements
- offshore crane and drawworks drums
Known failure patterns
- cone-raceway spalling at the large rib when preload is set too high for the lubricant film
- 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
- water-induced pitting when the open bearing is exposed to washdown without external seals
Selection pitfalls — read before you substitute
- At 170 mm bore the 32934XU set is adjusted with hydraulic nuts on large mill and wind positions; follow the drive-up angle/end-play procedure, because manual torque methods cannot control preload at the 315 kN C level.
- The thin 38 mm section of 32934XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 170 mm bore smears the roller ends against the rib.
- Do not confuse T (38 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.
- Grease packs must leave free volume in the 38 mm-wide set; over-greasing a paired bearing churning at the 1,800 r/min oil-band speed raises temperature and destroys the preload setting.
- Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 170 mm shoulder geometry, because retrofitting flips the cups.
- The 315/560 kN ratings and 55 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32934XU (ISO 355 3DC); 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 32934XU?
32934XU is a metric 4T tapered roller bearing to ISO 355: 170 mm bore, 230 mm outside diameter and 38 mm assembled width T (6.693 × 9.055 × 1.496 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 315 kN, C0 560 kN, Pu 55 kN, grease limiting speed 1,400 r/min, oil speed 1,800 r/min, mass about 4400 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 32934XU?
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 (32934XU); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 32934XU designation encode the 170 mm bore and what is 3DC?
last two digits 34 are the ISO bore code, ×5 = 170 mm (codes 00–03 use the 10/12/15/17 exception table). The 230 mm OD and 38 mm assembled T follow the ISO 355 dimension-series plan. 3DC 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 32934XU list two speeds, 1,400 and 1,800 r/min?
The lower figure, 1,400 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32934XU at 1,800 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 32934XU mean?
Suffix reading on 32934XU: XU combines the X ISO boundary section with the U uprated internal design; 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.