JL724348-JL724314 bearing: complete specifications & equivalents
The JL724348-JL724314 is a ANSI ABMA 19.2 radial bearing sized 120 x 170 x 25.4 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 120 mm |
| Outer diameter D | 170 mm |
| Width B | 25.4 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 141 kN |
| Basic static load rating C0 | 210 kN |
| Limiting speed (mechanical) | 2000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1670 g |
| Manufacturer designation | NTN 4T-JL724348/JL724314 |
| 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 | 4.724 in |
|---|---|
| Outer diameter D | 6.693 in |
| Width B | 1 in |
| ISO bore code | 48 |
| Radial section height (D−d)/2 | 25 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) | 130 of 148 |
| Bore above smallest 4t-inch-series size | 107.3 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| JL724348 | 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 JL724348-JL724314 model number is decoded
4T-JL724348/JL724314 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 120×170×25.4 mm (assembled width T), for a shaft of about 120 mm (4.724 in). Reading the designation: 4T-JL724348/JL724314 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 JL prefixed family lettering ties the pair to its boundary plan. The 25.0 mm radial section over the 120 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 141/210 kN ratings belong to the assembled JL724348+JL724314 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. Back-to-back (O) and face-to-face (X) arrangements of two 4T-JL724348/JL724314 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.
Typical equipment & failure modes
Common applications
- large shredder and recycler main shafts
- power-plant coal-mill and fan shafts
- rolling-mill pinion stands and roll-neck auxiliaries
- mine hoist and dragline drum shafts
Known failure patterns
- cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film
- cup creep and housing fretting when the cup seat is cut too loose for the rotating load
- flaking on one cone only when a bent shaft loads the O/X pair unevenly
- cage damage from a mounting blow transmitted through the roller complement
- water-induced pitting when the open bearing sees washdown without external seals
Selection pitfalls — read before you substitute
- At 120 mm bore the 4T-JL724348/JL724314 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 141 kN C level.
- The J-prefixed JL724348 code belongs to a metric-envelope inch family: its 120 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.
- An unloaded 4T-JL724348/JL724314 near 2,000 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.
- ABMA makes the 120×170 mm envelope interchangeable, not the ratings: NTN prints 141/210 kN for this execution and another make of the same number can differ in roller complement.
- Open 4T-JL724348/JL724314 sets have no seals: a hub or gearbox needs external sealing or the 2,000 r/min grease figure is meaningless once water reaches the cone rib.
- The 141/210 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-JL724348/JL724314; 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-JL724348/JL724314?
4T-JL724348/JL724314 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 120 mm bore (4.724 in), 170 mm outside diameter and 25.4 mm assembled width T (6.693 × 1 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 141 kN, C0 210 kN, grease limiting speed 2,000 r/min, oil speed 2,600 r/min, mass about 1670 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-JL724348/JL724314 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the JL724348 cone or the JL724314 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 141/210 kN ratings change with the cup.
What is the difference between 4T-JL724348/JL724314 and a metric ISO 355 tapered bearing?
4T-JL724348/JL724314 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 120×170×25.4 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-JL724348/JL724314 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 JL724348/JL724314 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-JL724348/JL724314 list two speeds, 2,000 and 2,600 r/min?
The lower figure, 2,000 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-JL724348/JL724314 at 2,600 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.