45280-45220 bearing: complete specifications & equivalents
The 45280-45220 is a ANSI ABMA 19.2 radial bearing sized 44.45 x 104.775 x 30.162 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 44.45 mm |
| Outer diameter D | 104.775 mm |
| Width B | 30.162 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 144 kN |
| Basic static load rating C0 | 169 kN |
| Limiting speed (mechanical) | 3500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1330 g |
| Manufacturer designation | NTN 4T-45280/45220 |
| Standard | ANSI ABMA 19.2 |
| Catalog version | NTN 2203E 2026-09-25 |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN 2203E 2026-09-25) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN 2203E 2026-09-25); 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 & 4t-inch-series range
| Bore d | 1.75 in |
|---|---|
| Outer diameter D | 4.125 in |
| Width B | 1.187 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 30.2 mm |
| Smallest bore in 4t-inch-series | 12.7 mm |
| Largest outer diameter in 4t-inch-series | 260 mm |
| Width range across 4t-inch-series | 10.998–77.788 mm |
| Bore position in 4t-inch-series (smallest first) | 51 of 148 |
| Bore above smallest 4t-inch-series size | 31.750000000000004 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 45280 | 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 45280-45220 model number is decoded
NTN supplies this 1.75 in (44.45 mm) shaft position as 4T-45280/45220: cone 45280, cup 45220, profiled rollers and a pressed-steel cage, rated 144 kN basic dynamic and 169 kN static. Reading the designation: 4T-45280/45220 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 3.2 kN of dynamic capacity per millimetre of bore summarises the 144 kN rating over the 44.45 mm bore — sanity-check any interchange candidate against this ratio and the 30.162 mm T. The printed 144/169 kN ratings belong to the assembled 45280+45220 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. NTN grades inch 4T bearings as open bearings without integral seals; at 44.45 mm bore the application supplies sealing and the grease fill or oil feed.
Typical equipment & failure modes
Common applications
- pump and blower drive shafts with combined load
- truck and trailer axle hubs on inch-dimensioned axles
- agricultural tractor transmission and PTO shafts
- industrial gearboxes built to inch shafting
Known failure patterns
- rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries
- flaking on one cone only when a bent shaft loads the O/X pair unevenly
- cup creep and housing fretting when the cup seat is cut too loose for the rotating load
- pressed-steel cage pocket wear from roller skid at light radial load and high speed
- indentation of the raceways by hard particles in an open, unsealed arrangement
Selection pitfalls — read before you substitute
- Hub and pinion positions of this 44.45 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-45280/45220.
- The pure-numeric inch family at 44.45 mm bore (104.775×30.162 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 45280/45220 reference at purchase.
- Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.
- Inch and metric bores collide on paper — 44.45 mm is 1.75 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.
- Do not confuse T (30.162 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.
- The 144/169 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-45280/45220; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 4T-45280/45220?
4T-45280/45220 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 44.45 mm bore (1.75 in), 104.775 mm outside diameter and 30.162 mm assembled width T (4.125 × 1.187 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 144 kN, C0 169 kN, grease limiting speed 3,500 r/min, oil speed 4,700 r/min, mass about 1330 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-45280/45220 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the 45280 cone or the 45220 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 144/169 kN ratings change with the cup.
What is the difference between 4T-45280/45220 and a metric ISO 355 tapered bearing?
4T-45280/45220 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 44.45×104.775×30.162 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting.
What does the 4T prefix on 4T-45280/45220 mean?
4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 45280/45220 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-45280/45220 list two speeds, 3,500 and 4,700 r/min?
The lower figure, 3,500 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-45280/45220 at 4,700 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN 2203E 2026-09-25 on 2026-10-01. Read our editorial & correction policy.