02877-02820 bearing: complete specifications & equivalents
The 02877-02820 is a ANSI ABMA 19.2 radial bearing sized 34.925 x 73.025 x 22.225 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 34.925 mm |
| Outer diameter D | 73.025 mm |
| Width B | 22.225 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 62.5 kN |
| Basic static load rating C0 | 68 kN |
| Limiting speed (mechanical) | 5300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 423 g |
| Manufacturer designation | NTN 4T-02877/02820 |
| 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 | 1.375 in |
|---|---|
| Outer diameter D | 2.875 in |
| Width B | 0.875 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 19.1 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) | 34 of 148 |
| Bore above smallest 4t-inch-series size | 22.224999999999998 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 02877 | 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 02877-02820 model number is decoded
4T-02877/02820 belongs to the NTN inch 4T tapered roller range (pure-numeric inch family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote 02877/02820 without it. Speed planning uses both catalogue columns: grease 5,300 r/min is the mechanical ceiling for 4T-02877/02820, oil 7,000 r/min with circulating oil — a 1,700 r/min margin at this size. Housing fitment sequence for 4T-02877/02820: press the 02820 cup square into the 73.025 mm seat first, then bring the 02877 cone (on its 34.925 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. With a rotating shaft a k5/m5 cone seat and an easy-push cup seat are typical practice for 4T-02877/02820; reverse the fit logic when the cup rotates.
Typical equipment & failure modes
Common applications
- industrial gearboxes built to inch shafting
- construction-equipment pivot and wheel positions
- mining and quarry conveyor drive pulleys
- machine-tool headstocks on inch spindles
Known failure patterns
- cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film
- 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
- cage damage from a mounting blow transmitted through the roller complement
- fretting corrosion on a loose cone seat that creeps under rotating load
Selection pitfalls — read before you substitute
- Hub and pinion positions of this 34.925 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-02877/02820.
- The pure-numeric inch family at 34.925 mm bore (73.025×22.225 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 02877/02820 reference at purchase.
- Inch and metric bores collide on paper — 34.925 mm is 1.375 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.
- Fit selection follows the rotating ring: a rotating cone on a 34.925 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.
- Fit selection follows the rotating ring: a rotating cone on a 34.925 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.
- The 62.5/68 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-02877/02820; 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-02877/02820?
4T-02877/02820 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.925 mm bore (1.375 in), 73.025 mm outside diameter and 22.225 mm assembled width T (2.875 × 0.875 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 62.5 kN, C0 68 kN, grease limiting speed 5,300 r/min, oil speed 7,000 r/min, mass about 423 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-02877/02820 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the 02877 cone or the 02820 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 62.5/68 kN ratings change with the cup.
What is the difference between 4T-02877/02820 and a metric ISO 355 tapered bearing?
4T-02877/02820 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 34.925×73.025×22.225 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-02877/02820 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 02877/02820 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-02877/02820 list two speeds, 5,300 and 7,000 r/min?
The lower figure, 5,300 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-02877/02820 at 7,000 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.