JLM704649-JLM704610 bearing: complete specifications & equivalents
The JLM704649-JLM704610 is a ANSI ABMA 19.2 radial bearing sized 50 x 84 x 22 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 50 mm |
| Outer diameter D | 84 mm |
| Width B | 22 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 77.5 kN |
| Basic static load rating C0 | 94.5 kN |
| Limiting speed (mechanical) | 4300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 466 g |
| Manufacturer designation | NTN 4T-JLM704649/JLM704610 |
| 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 | 1.969 in |
|---|---|
| Outer diameter D | 3.307 in |
| Width B | 0.866 in |
| ISO bore code | 49 |
| 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) | 63 of 148 |
| Bore above smallest 4t-inch-series size | 37.3 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| JLM704649 | 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 JLM704649-JLM704610 model number is decoded
4T-JLM704649/JLM704610 belongs to the NTN inch 4T tapered roller range (JLM prefixed family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Reading the designation: 4T-JLM704649/JLM704610 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 JLM prefixed family lettering ties the pair to its boundary plan. Grease relubrication at the 4,300 r/min limiting speed targets the cone-rib contact; sustaining 5,700 r/min needs an oil supply directed at the large roller ends. Housing fitment sequence for 4T-JLM704649/JLM704610: press the JLM704610 cup square into the 84 mm seat first, then bring the JLM704649 cone (on its 50 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. After bedding-in, re-check the end play of the adjusted 4T-JLM704649/JLM704610 pair — initial seating of the ring faces relaxes the setting slightly.
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
- 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 fatigue when the pair runs continuously near the grease limiting speed without oil cooling
- fretting corrosion on a loose cone seat that creeps under rotating load
Selection pitfalls — read before you substitute
- Hub and pinion positions of this 50 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-JLM704649/JLM704610.
- The J-prefixed JLM704649 code belongs to a metric-envelope inch family: its 50 mm bore is a round metric figure, yet the part still follows ABMA cone/cup numbering — do not substitute an ISO 355 metric 302/322 bearing of the same bore without checking OD, T and contact angle.
- Shaft and housing fillets must clear the ring chamfers of JLM704649 and JLM704610; use undercut shoulders so the rings seat on the face, not on a radius.
- Shaft and housing fillets must clear the ring chamfers of JLM704649 and JLM704610; use undercut shoulders so the rings seat on the face, not on a radius.
- Grease packs must leave free volume inside the 22 mm-wide set; over-greasing a pair churning near the oil-band speed of 5,700 r/min raises temperature and destroys the setting.
- The 77.5/94.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JLM704649/JLM704610; 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-JLM704649/JLM704610?
4T-JLM704649/JLM704610 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50 mm bore (1.969 in), 84 mm outside diameter and 22 mm assembled width T (3.307 × 0.866 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 77.5 kN, C0 94.5 kN, grease limiting speed 4,300 r/min, oil speed 5,700 r/min, mass about 466 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-JLM704649/JLM704610 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the JLM704649 cone or the JLM704610 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 77.5/94.5 kN ratings change with the cup.
What is the difference between 4T-JLM704649/JLM704610 and a metric ISO 355 tapered bearing?
4T-JLM704649/JLM704610 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 50×84×22 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-JLM704649/JLM704610 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 JLM704649/JLM704610 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-JLM704649/JLM704610 list two speeds, 4,300 and 5,700 r/min?
The lower figure, 4,300 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-JLM704649/JLM704610 at 5,700 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.