33022U bearing: complete specifications & equivalents
The 33022U is a ISO 355 radial bearing sized 110 x 170 x 47 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 110 mm |
| Outer diameter D | 170 mm |
| Width B | 47 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 320 kN |
| Basic static load rating C0 | 500 kN |
| Fatigue load limit Pu | 55.5 kN |
| Limiting speed (mechanical) | 2000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 3840 g |
| Manufacturer designation | NTN 33022U |
| 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 & 33000-series range
| Bore d | 4.331 in |
|---|---|
| Outer diameter D | 6.693 in |
| Width B | 1.85 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in 33000-series | 25 mm |
| Largest outer diameter in 33000-series | 225 mm |
| Width range across 33000-series | 17–59 mm |
| Bore position in 33000-series (smallest first) | 20 of 24 |
| Bore above smallest 33000-series size | 85 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 33022U | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier. |
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 33022U model number is decoded
33022U is the NTN 4T catalogue entry for a 110×170×47 mm metric tapered roller bearing — separable cone and cup, designed for combined radial and axial load as an individually adjusted bearing. Digit by digit, the bare number identifies the slim 33000 family and a bore code resolving to 110 mm; 170 mm OD and 47 mm assembled T are the matching ISO 355 boundary dimensions shared with other makers of the same dimension series. 2203E lists two speed ceilings for 33022U: 2,000 r/min with grease lubrication (the limiting speed) and 2,700 r/min with oil, the higher oil value reflecting better heat removal from the cone rib. Speed planning uses both catalogue columns: grease 2,000 r/min is the cage/rib mechanical ceiling for 33022U, oil 2,700 r/min is available with circulating oil — a 700 r/min margin at this size. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 110 mm pair is misadjusted and the 47 mm T set will edge-load in service.
Typical equipment & failure modes
Common applications
- large agricultural and forestry machine axles
- heavy industrial gearboxes and crane travel drives
- rolling-mill auxiliary and pinion-stand shafts
- large conveyor and bucket-elevator pulleys
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
- brinell marks on cone and cup raceways from impact during handling or hammering during fitting
Selection pitfalls — read before you substitute
- Mount the 110 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3840 g ring mass makes cocking during fitting a direct raceway-brinelling risk.
- The thin 47 mm section of 33022U is built for low friction and tight envelopes, not the heavy preload of a 322/323 set; over-tightening adjustment on this 110 mm bore smears the roller ends against the rib.
- Do not confuse T (47 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.
- ISO 355 makes the 110×170 mm envelope interchangeable but not the ratings: NTN prints 320/500 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.
- Grease packs must leave free volume in the 47 mm-wide set; over-greasing a paired bearing churning at the 2,700 r/min oil-band speed raises temperature and destroys the preload setting.
- The 320/500 kN ratings and 55.5 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 33022U (ISO 355 2DE); 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 33022U?
33022U is a metric 4T tapered roller bearing to ISO 355: 110 mm bore, 170 mm outside diameter and 47 mm assembled width T (4.331 × 6.693 × 1.85 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 320 kN, C0 500 kN, Pu 55.5 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 3840 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 33022U?
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 (33022U); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 33022U designation encode the 110 mm bore and what is 2DE?
last two digits 22 are the ISO bore code, ×5 = 110 mm (codes 00–03 use the 10/12/15/17 exception table). The 170 mm OD and 47 mm assembled T follow the ISO 355 dimension-series plan. 2DE 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 33022U list two speeds, 2,000 and 2,700 r/min?
The lower figure, 2,000 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 33022U at 2,700 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 33022U mean?
Suffix reading on 33022U: 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.