32930XU bearing: complete specifications & equivalents
The 32930XU is a ISO 355 radial bearing sized 150 x 210 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 | 150 mm |
| Outer diameter D | 210 mm |
| Width B | 38 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 297 kN |
| Basic static load rating C0 | 490 kN |
| Fatigue load limit Pu | 50 kN |
| Limiting speed (mechanical) | 1600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 3930 g |
| Manufacturer designation | NTN 32930XU |
| 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 | 5.906 in |
|---|---|
| Outer diameter D | 8.268 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) | 20 of 37 |
| Bore above smallest 32900-series size | 115 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32930XU | 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 32930XU model number is decoded
The NTN 2203E table prints 32930XU in the extra-light thin-section 32900 family: 150 mm bore, 210 mm cup OD, 38 mm T, with a grease limiting speed of 1,600 r/min and an oil-lubricated ceiling of 2,100 r/min. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32930XU resolves to 150 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. 2203E lists two speed ceilings for 32930XU: 1,600 r/min with grease lubrication (the limiting speed) and 2,100 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Selection: C 297 kN against C0 490 kN gives a C0/C ratio of 1.65 for the 150 mm bore, and the equivalent combined load must keep below the rating at the target L10 with the pair counted as one unit. Open 4T bearings need application seals; without them the grease at the cone rib of 32930XU washes out and the rib/roller-end contact smears on the first wet or dusty shift.
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
- 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
- At 150 mm bore the 32930XU 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 297 kN C level.
- The thin 38 mm section of 32930XU is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 150 mm bore smears the roller ends against the rib.
- Open 32930XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,600 r/min grease figure is meaningless once water reaches the cone rib.
- Open 32930XU units have no seals: a wheel-hub or gearbox application needs external sealing or the 1,600 r/min grease figure is meaningless once water reaches the cone rib.
- Grease packs must leave free volume in the 38 mm-wide set; over-greasing a paired bearing churning at the 2,100 r/min oil-band speed raises temperature and destroys the preload setting.
- The 297/490 kN ratings and 50 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32930XU (ISO 355 2DC); 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 32930XU?
32930XU is a metric 4T tapered roller bearing to ISO 355: 150 mm bore, 210 mm outside diameter and 38 mm assembled width T (5.906 × 8.268 × 1.496 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 297 kN, C0 490 kN, Pu 50 kN, grease limiting speed 1,600 r/min, oil speed 2,100 r/min, mass about 3930 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 32930XU?
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 (32930XU); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 32930XU designation encode the 150 mm bore and what is 2DC?
last two digits 30 are the ISO bore code, ×5 = 150 mm (codes 00–03 use the 10/12/15/17 exception table). The 210 mm OD and 38 mm assembled T follow the ISO 355 dimension-series plan. 2DC 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 32930XU list two speeds, 1,600 and 2,100 r/min?
The lower figure, 1,600 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32930XU at 2,100 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 32930XU mean?
Suffix reading on 32930XU: 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.