33215U bearing: complete specifications & equivalents
The 33215U is a ISO 355 radial bearing sized 75 x 130 x 41 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 | 41 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 231 kN |
| Basic static load rating C0 | 298 kN |
| Fatigue load limit Pu | 36 kN |
| Limiting speed (mechanical) | 2700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2230 g |
| Manufacturer designation | NTN 33215U |
| 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 & 33200-series range
| Bore d | 2.953 in |
|---|---|
| Outer diameter D | 5.118 in |
| Width B | 1.614 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 27.5 mm |
| Smallest bore in 33200-series | 25 mm |
| Largest outer diameter in 33200-series | 180 mm |
| Width range across 33200-series | 22–63 mm |
| Bore position in 33200-series (smallest first) | 13 of 18 |
| Bore above smallest 33200-series size | 50 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 33215U | 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 33215U model number is decoded
33215U belongs to the NTN metric 4T tapered roller range (medium-wide 33200 family); the open bearing leaves sealing to the application and is normally ordered and mounted as an adjustable matched pair. The last two digits 15 are the ISO bore code, ×5 = 75 mm (codes 00–03 use the 10/12/15/17 exception table) under the ISO 355 numbering; the 41 mm value printed here is T, the width of the fully assembled cone-plus-cup set, not the inner-ring width alone. The printed contact-angle geometry gives the medium-wide 33200 family its characteristic load split — at 231/298 kN (C/C0) the static rating is about 1.29× C, typical of tapered bearings proportioned for heavy combined duty. Grease relubrication at 2,700 r/min limiting speed targets the rib contact; if the drive needs 3,600 r/min it must be arranged for oil lubrication with a defined flow to the large roller ends. With a rotating shaft a k5/m5 shaft seat and a press-fit cup are typical catalogue practice for 33215U; reverse the logic if the cup rotates, and re-verify against load direction and magnitude.
Typical equipment & failure modes
Common applications
- large conveyor and bucket-elevator pulleys
- mineral-processing feeder and crusher auxiliaries
- marine winch and deck-machinery shafts
- paper-machine press-section rolls
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
- indentation of the raceways by hard particles in unsealed open arrangements
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 2230 g ring mass makes cocking during fitting a direct raceway-brinelling risk.
- The medium-wide 33200 family at 75 mm bore (130×41 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.
- The U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 33215U by size alone can deliver the wrong contact-angle execution for a pinion position.
- Back-to-back and face-to-face arrangements react differently to shaft bending: pick the pair orientation for the moment load before locking the 75 mm shoulder geometry, because retrofitting flips the cups.
- Minimum load matters at high speed: an unloaded 33215U at a large fraction of 2,700 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded pair arrangements.
- The 231/298 kN ratings and 36 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33215U (ISO 355 3EE); 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 33215U?
33215U is a metric 4T tapered roller bearing to ISO 355: 75 mm bore, 130 mm outside diameter and 41 mm assembled width T (2.953 × 5.118 × 1.614 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 231 kN, C0 298 kN, Pu 36 kN, grease limiting speed 2,700 r/min, oil speed 3,600 r/min, mass about 2230 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 33215U?
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 (33215U); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 33215U designation encode the 75 mm bore and what is 3EE?
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 41 mm assembled T follow the ISO 355 dimension-series plan. 3EE 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 33215U 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 33215U 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 33215U mean?
Suffix reading on 33215U: 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.