32215U bearing: complete specifications & equivalents
The 32215U is a ISO 355 radial bearing sized 75 x 130 x 33.25 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 75 mm |
| Outer diameter D | 130 mm |
| Width B | 33.25 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 186 kN |
| Basic static load rating C0 | 224 kN |
| Fatigue load limit Pu | 27.1 kN |
| Limiting speed (mechanical) | 2700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1740 g |
| Manufacturer designation | NTN 32215U |
| 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 & 32200-series range
| Bore d | 2.953 in |
|---|---|
| Outer diameter D | 5.118 in |
| Width B | 1.309 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 27.5 mm |
| Smallest bore in 32200-series | 17 mm |
| Largest outer diameter in 32200-series | 580 mm |
| Width range across 32200-series | 17.25–159 mm |
| Bore position in 32200-series (smallest first) | 14 of 36 |
| Bore above smallest 32200-series size | 58 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32215U | 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 32215U model number is decoded
32215U is a metric single-row tapered roller bearing in the NTN 4T programme: a pressed-steel cage guides profiled rollers between a separable cone and cup on the 75×130 mm ISO 355 envelope, with 33.25 mm overall assembled width T. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32215U resolves to 75 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. A tapered roller bearing reacts combined radial and one-direction axial load; NTN mounts 32215U cone and cup separately and adjusts end play or preload against a second bearing, so the arrangement locates the shaft in both directions. The 2.5 kN-per-mm-bore capacity figure for 32215U summarises the 186 kN rating over 75 mm bore; use it to sanity-check an interchange candidate before swapping brands. Open 4T bearings need application seals; without them the grease at the cone rib of 32215U washes out and the rib/roller-end contact smears on the first wet or dusty shift.
Typical equipment & failure modes
Common applications
- heavy industrial gearboxes and crane travel drives
- rolling-mill auxiliary and pinion-stand shafts
- large conveyor and bucket-elevator pulleys
- mineral-processing feeder and crusher auxiliaries
Known failure patterns
- cup creep and housing fretting when the specified outer-ring press fit is not achieved
- flaking on one cone only when a back-to-back / face-to-face pair is loaded unevenly by a bent shaft
- smearing on the roller large ends and cone rib after a dry start with preload but no oil film
- 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
- Mount the 75 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 1740 g ring mass makes cocking during fitting a direct raceway-brinelling risk.
- The heavy-section 32200 family at 75 mm bore (130×33.25 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 3,600 r/min oil ceiling.
- Do not confuse T (33.25 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 33.25 mm-wide set; over-greasing a paired bearing churning at the 3,600 r/min oil-band speed raises temperature and destroys the preload setting.
- Do not confuse T (33.25 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.
- The 186/224 kN ratings and 27.1 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32215U (ISO 355 4DC); 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 32215U?
32215U is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 130 mm outside diameter and 33.25 mm assembled width T (2.953 × 5.118 × 1.309 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 186 kN, C0 224 kN, Pu 27.1 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 1740 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 32215U?
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 (32215U); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 32215U designation encode the 75 mm bore and what is 4DC?
last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table). The 130 mm OD and 33.25 mm assembled T follow the ISO 355 dimension-series plan. 4DC 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 32215U list two speeds, 2,700 and 3,600 r/min?
The lower figure, 2,700 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32215U at 3,600 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 32215U mean?
Suffix reading on 32215U: 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.