30220U bearing: complete specifications & equivalents
The 30220U is a ISO 355 radial bearing sized 100 x 180 x 37 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 100 mm |
| Outer diameter D | 180 mm |
| Width B | 37 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 286 kN |
| Basic static load rating C0 | 335 kN |
| Fatigue load limit Pu | 37 kN |
| Limiting speed (mechanical) | 2000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 3760 g |
| Manufacturer designation | NTN 30220U |
| 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 & 30200-series range
| Bore d | 3.937 in |
|---|---|
| Outer diameter D | 7.087 in |
| Width B | 1.457 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 40 mm |
| Smallest bore in 30200-series | 15 mm |
| Largest outer diameter in 30200-series | 580 mm |
| Width range across 30200-series | 11.75–104 mm |
| Bore position in 30200-series (smallest first) | 20 of 37 |
| Bore above smallest 30200-series size | 85 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 30220U | 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 30220U model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, the NTN order number 30220U denotes the standard-section 30200 family of metric tapered roller bearings, 100 mm bore, 180 mm outside diameter and 37 mm assembled width T (3.937 × 7.087 × 1.457 in) to the ISO 355 boundary plan. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 30220U resolves to 100 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. Individually mounted, 30220U takes axial force in one direction only; two bearings are arranged face-to-face (X) or back-to-back (O) according to the moment stiffness and misalignment the shaft requires. Imperial cross-check for the drawing: 100×180×37 mm is 3.937 × 7.087 × 1.457 in; ISO 355 makes the envelope interchangeable but C/C0, 286/335 kN, is NTN-specific. Re-adjustment after bedding-in is standard practice: re-check end play once the paired 30220U arrangement has run in, because initial seat seating relaxes the set preload slightly.
Typical equipment & failure modes
Common applications
- marine winch and deck-machinery shafts
- paper-machine press-section rolls
- large agricultural and forestry machine axles
- heavy industrial gearboxes and crane travel drives
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
- cage damage from a mounting blow delivered through the roller complement instead of the ring face
- water-induced pitting when the open bearing is exposed to washdown without external seals
Selection pitfalls — read before you substitute
- Mount the 100 mm cone by induction heating (max 120 °C) and the cup with a press sleeve; the 3760 g ring mass makes cocking during fitting a direct raceway-brinelling risk.
- The standard-section 30200 family at 100 mm bore (180×37 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 2,700 r/min oil ceiling.
- Grease packs must leave free volume in the 37 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 U/UTG/X/C/CA/D suffix variants of a base number share the bore but not the article: ordering 30220U by size alone can deliver the wrong contact-angle execution for a pinion position.
- Never fit the 100 mm cone by hammering the 180 mm cup: force for both press fits goes through the ring faces only, or brinell marks release as noise within the first running hours.
- The 286/335 kN ratings and 37 kN Pu here are NTN Ball and Roller Bearings CAT.No.2203E figures for 30220U (ISO 355 3FB); 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 30220U?
30220U is a metric 4T tapered roller bearing to ISO 355: 100 mm bore, 180 mm outside diameter and 37 mm assembled width T (3.937 × 7.087 × 1.457 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 286 kN, C0 335 kN, Pu 37 kN, grease limiting speed 2,000 r/min, oil speed 2,700 r/min, mass about 3760 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 30220U?
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 (30220U); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 30220U designation encode the 100 mm bore and what is 3FB?
last two digits 20 are the ISO bore code, ×5 = 100 mm (codes 00–03 use the 10/12/15/17 exception table). The 180 mm OD and 37 mm assembled T follow the ISO 355 dimension-series plan. 3FB 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 30220U 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 30220U 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 30220U mean?
Suffix reading on 30220U: 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.