14139-14276 bearing: complete specifications & equivalents
The 14139-14276 is a ANSI ABMA 19.2 radial bearing sized 34.976 x 69.012 x 19.845 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 34.976 mm |
| Outer diameter D | 69.012 mm |
| Width B | 19.845 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 53.5 kN |
| Basic static load rating C0 | 58 kN |
| Limiting speed (mechanical) | 5600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 330 g |
| Manufacturer designation | NTN 4T-14139/14276 |
| 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 | 1.377 in |
|---|---|
| Outer diameter D | 2.717 in |
| Width B | 0.781 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 17 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) | 35 of 148 |
| Bore above smallest 4t-inch-series size | 22.276 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 14139 | 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 14139-14276 model number is decoded
NTN supplies this 1.377 in (34.976 mm) shaft position as 4T-14139/14276: cone 14139, cup 14276, profiled rollers and a pressed-steel cage, rated 53.5 kN basic dynamic and 58 kN static. 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 14139/14276 without it. Speed planning uses both catalogue columns: grease 5,600 r/min is the mechanical ceiling for 4T-14139/14276, oil 7,400 r/min with circulating oil — a 1,800 r/min margin at this size. Housing fitment sequence for 4T-14139/14276: press the 14276 cup square into the 69.012 mm seat first, then bring the 14139 cone (on its 34.976 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-14139/14276; 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
- 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
- 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 34.976 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-14139/14276.
- The pure-numeric inch family at 34.976 mm bore (69.012×19.845 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 14139/14276 reference at purchase.
- Quote the full 14139/14276 pair at ordering: the 14139 cone also ships against sibling cups, and a cup from another reference changes the 19.845 mm assembled width and the rating.
- Do not confuse T (19.845 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.
- Open 4T-14139/14276 sets have no seals: a hub or gearbox needs external sealing or the 5,600 r/min grease figure is meaningless once water reaches the cone rib.
- The 53.5/58 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-14139/14276; 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-14139/14276?
4T-14139/14276 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.976 mm bore (1.377 in), 69.012 mm outside diameter and 19.845 mm assembled width T (2.717 × 0.781 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 53.5 kN, C0 58 kN, grease limiting speed 5,600 r/min, oil speed 7,400 r/min, mass about 330 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-14139/14276 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the 14139 cone or the 14276 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 53.5/58 kN ratings change with the cup.
What is the difference between 4T-14139/14276 and a metric ISO 355 tapered bearing?
4T-14139/14276 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 34.976×69.012×19.845 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-14139/14276 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 14139/14276 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-14139/14276 list two speeds, 5,600 and 7,400 r/min?
The lower figure, 5,600 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-14139/14276 at 7,400 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.