L610549-L610510 bearing: complete specifications & equivalents
The L610549-L610510 is a ANSI ABMA 19.2 radial bearing sized 63.5 x 94.458 x 19.05 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 63.5 mm |
| Outer diameter D | 94.458 mm |
| Width B | 19.05 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 67 kN |
| Basic static load rating C0 | 103 kN |
| Limiting speed (mechanical) | 3600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 453 g |
| Manufacturer designation | NTN 4T-L610549/L610510 |
| 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 | 2.5 in |
|---|---|
| Outer diameter D | 3.719 in |
| Width B | 0.75 in |
| ISO bore code | 49 |
| Radial section height (D−d)/2 | 15.5 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) | 81 of 148 |
| Bore above smallest 4t-inch-series size | 50.8 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| L610549 | 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 L610549-L610510 model number is decoded
4T-L610549/L610510 belongs to the NTN inch 4T tapered roller range (light L family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: L610549 identifies the cone of 63.5 mm (2.5 in) bore by catalogue lookup, and L610510 fixes the 94.458 mm OD. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 19.05 mm T of each 4T-L610549/L610510 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for L610510: within the light L family tables the L610549 cone is listed against several cup options, and it is the cup that fixes the 94.458 mm OD and the 19.05 mm assembled width — quote the full L610549/L610510 pair, never the cone alone. A single-row tapered bearing reacts thrust in one direction only; 4T-L610549/L610510 is adjusted against a second bearing so the shaft is located in both directions.
Typical equipment & failure modes
Common applications
- large conveyor head pulleys in bulk-handling plant
- paper-machine and calender roll supports
- off-highway and forestry machine axles
- marine winch and deck-machinery shafts
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
- rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load
Selection pitfalls — read before you substitute
- Mount the 63.5 mm cone by induction heating (max 120 °C) and the 94.458 mm cup with a press sleeve; at 453 g a cocked ring brinells the raceway directly.
- The light L family at 63.5 mm bore (94.458×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L610549/L610510 reference at purchase.
- Shaft and housing fillets must clear the ring chamfers of L610549 and L610510; use undercut shoulders so the rings seat on the face, not on a radius.
- Inch and metric bores collide on paper — 63.5 mm is 2.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.
- Open 4T-L610549/L610510 sets have no seals: a hub or gearbox needs external sealing or the 3,600 r/min grease figure is meaningless once water reaches the cone rib.
- The 67/103 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L610549/L610510; 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-L610549/L610510?
4T-L610549/L610510 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 63.5 mm bore (2.5 in), 94.458 mm outside diameter and 19.05 mm assembled width T (3.719 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 67 kN, C0 103 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 453 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-L610549/L610510 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the L610549 cone or the L610510 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 67/103 kN ratings change with the cup.
What is the difference between 4T-L610549/L610510 and a metric ISO 355 tapered bearing?
4T-L610549/L610510 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 63.5×94.458×19.05 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-L610549/L610510 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 L610549/L610510 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-L610549/L610510 list two speeds, 3,600 and 4,800 r/min?
The lower figure, 3,600 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-L610549/L610510 at 4,800 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.