938-932-NTN bearing: complete specifications & equivalents
The 938-932-NTN is a ANSI ABMA 19.2 radial bearing sized 114.3 x 212.725 x 66.675 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 114.3 mm |
| Outer diameter D | 212.725 mm |
| Width B | 66.675 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 525 kN |
| Basic static load rating C0 | 695 kN |
| Limiting speed (mechanical) | 1800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 10100 g |
| Manufacturer designation | NTN 4T-938/932 |
| 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 | 4.5 in |
|---|---|
| Outer diameter D | 8.375 in |
| Width B | 2.625 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 49.2 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) | 127 of 148 |
| Bore above smallest 4t-inch-series size | 101.6 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 938-932 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 114.3×212.725×66.675 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
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 938-932-NTN model number is decoded
NTN supplies this 4.5 in (114.3 mm) shaft position as 4T-938/932: cone 938, cup 932, profiled rollers and a pressed-steel cage, rated 525 kN basic dynamic and 695 kN static. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — 938 sits in the pure-numeric inch family. Grease relubrication at the 1,800 r/min limiting speed targets the cone-rib contact; sustaining 2,300 r/min needs an oil supply directed at the large roller ends. Cup-side note for 932: within the pure-numeric inch family tables the 938 cone is listed against several cup options, and it is the cup that fixes the 212.725 mm OD and the 66.675 mm assembled width — quote the full 938/932 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-938/932 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.
Typical equipment & failure modes
Common applications
- mine hoist and dragline drum shafts
- heavy press and forging-machine drive shafts
- port-crane travel and hoist gearboxes
- cement-plant mill and kiln drive trains
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
- pressed-steel cage pocket wear from roller skid at light radial load and high speed
- brinell marks on cone and cup raceways from impact during handling or hammer fitting
Selection pitfalls — read before you substitute
- At 114.3 mm bore the 4T-938/932 set is adjusted with hydraulic nuts or measured shims on mill and crane positions; manual torque methods cannot control preload at the 525 kN C level.
- The pure-numeric inch family at 114.3 mm bore (212.725×66.675 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 938/932 reference at purchase.
- An unloaded 4T-938/932 near 1,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.
- Shaft and housing fillets must clear the ring chamfers of 938 and 932; use undercut shoulders so the rings seat on the face, not on a radius.
- Do not confuse T (66.675 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.
- The 525/695 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-938/932; 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-938/932?
4T-938/932 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 114.3 mm bore (4.5 in), 212.725 mm outside diameter and 66.675 mm assembled width T (8.375 × 2.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 525 kN, C0 695 kN, grease limiting speed 1,800 r/min, oil speed 2,300 r/min, mass about 10100 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-938/932 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the 938 cone or the 932 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 525/695 kN ratings change with the cup.
What is the difference between 4T-938/932 and a metric ISO 355 tapered bearing?
4T-938/932 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 114.3×212.725×66.675 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-938/932 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 938/932 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-938/932 list two speeds, 1,800 and 2,300 r/min?
The lower figure, 1,800 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-938/932 at 2,300 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.