232-750B bearing: complete specifications & equivalents
The 232-750B is a ISO 15 radial bearing sized 750 x 1360 x 475 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 750 mm |
| Outer diameter D | 1360 mm |
| Width B | 475 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 20300 kN |
| Basic static load rating C0 | 36500 kN |
| Fatigue load limit Pu | 1980 kN |
| Limiting speed (mechanical) | 180 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 3050000 g |
| Manufacturer designation | NTN 232/750B |
| Standard | ISO 15 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203E |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); 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 & 23200-series range
| Bore d | 29.528 in |
|---|---|
| Outer diameter D | 53.543 in |
| Width B | 18.701 in |
| ISO bore code | 32 |
| Radial section height (D−d)/2 | 305 mm |
| Smallest bore in 23200-series | 90 mm |
| Largest outer diameter in 23200-series | 1360 mm |
| Width range across 23200-series | 52.4–475 mm |
| Bore position in 23200-series (smallest first) | 34 of 34 |
| Bore above smallest 23200-series size | 660 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 232-750BK | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23200-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 232-750BK (K/K30 sleeve or tapered-seat mounting). Verify shaft arrangement. |
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 232-750B model number is decoded
NTN lists 232/750B with a cylindrical bore and plain outer ring (no D1/W33 groove): 750 mm bore, 1360 mm OD, 475 mm width, rated 180 r/min on grease. Numbering ties 232/750B to its envelope and execution: same-number EA versus EM or plain variants share the 750 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Pu 1980 kN is the catalogue fatigue load limit for 232/750B, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. Catalogue mass 3050000 g (3050.00 kg) for the 750×1360×475 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. Supply grease through the outer-ring feature during commissioning and at the calculated interval, rotating the 750 mm bore assembly by hand to distribute it across both rows.
Typical equipment & failure modes
Common applications
- large wind-turbine main-shaft arrangements
- steel-mill and heavy crusher main shafts
- mining shovel and dragline swing shafts
- cement-rotary-kiln support and trunnion rolls
Known failure patterns
- lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply
- pressed EA cage fatigue under sustained vibration when minimum load is not maintained
- roller-end smearing during skidding starts under light load and high viscosity grease
- false brinelling on stopped machines exposed to screen or crusher vibration
- rolling-contact fatigue after the catalogue L10 life at the actual load
Selection pitfalls — read before you substitute
- At 750 mm bore 232/750B is normally mounted on adapter/withdrawal sleeves with hydraulic assistance; follow the NTN drive-up angle or oil-injection procedure — manual nut tightening cannot set the multi-tonne seating correctly.
- Minimum load must be maintained even at rest under vibration: an unloaded 232/750B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 180 r/min grease rating is lost to abrasive wear long before fatigue.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 232/750B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 232/750B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- The 20300/36500 kN ratings, 1980 kN Pu and 3050000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 232/750B (basic); another maker's same-envelope part revises internal geometry, so re-verify ratings and cage before substitution on vibrating or rated drives.
Frequently asked questions
What are the dimensions and catalogue data of 232/750B?
232/750B is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1360 mm OD and 475 mm width (29.528 × 53.543 × 18.701 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 20300 kN, C0 36500 kN, Pu 1980 kN, grease limiting speed 180 r/min, oil 240 r/min, mass about 3050000 g. It is open, with pressed-steel cage (standard execution).
What is the difference between the K/K30 tapered bore and the cylindrical bore versions?
232/750B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 232/750BK (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting.
What do EA and EM mean on NTN spherical roller bearings?
EA is the NTN standard-capacity/high-capacity execution with a pressed sheet-steel window cage; EM is the high-capacity execution with a one-piece machined brass cage. Both use the optimised symmetric-roller design, but cage identity changes mass, speed behaviour and suitability for duties like vibrating screens, so they are separate order numbers. 232/750B is the basic execution.
What do D1 and W33 mean on 232/750B?
232/750B is listed without a D1/W33 outer-ring groove in 2203E; lubrication is supplied from the ring sides. D1 (NTN spelling) and W33 add the annular groove plus holes and are ordered as distinct suffixed executions of the same envelope.
How much misalignment and axial load can 232/750B take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23200 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 20300 kN C / 36500 kN C0 — but sustained pure axial load is not recommended because it unloads one row.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203E on 2026-10-01. Read our editorial & correction policy.