232-710BK bearing: complete specifications & equivalents
The 232-710BK is a ISO 15 radial bearing sized 710 x 1280 x 450 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 710 mm |
| Outer diameter D | 1280 mm |
| Width B | 450 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 18100 kN |
| Basic static load rating C0 | 32500 kN |
| Fatigue load limit Pu | 1200 kN |
| Limiting speed (mechanical) | 200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2470000 g |
| Manufacturer designation | NTN 232/710BK |
| 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 | 27.953 in |
|---|---|
| Outer diameter D | 50.394 in |
| Width B | 17.717 in |
| ISO bore code | 32 |
| Radial section height (D−d)/2 | 285 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) | 33 of 34 |
| Bore above smallest 23200-series size | 620 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 232-710B | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23200-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 232-710B — mounting (adapter/withdrawal sleeve or tapered seat, drive-up) differs. 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 232-710BK model number is decoded
232/710BK belongs to the 23200 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. Numbering ties 232/710BK to its envelope and execution: same-number EA versus EM or plain variants share the 710 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Open by design, 232/710BK requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. Selection: the C0/C ratio of 1.80 (32500/18100 kN) reflects the heavy static and shock proportioning of 232/710BK; size the equivalent load at the required L10 with shock factor for the application. Check the self-aligning movement after fitting: the housing should pivot freely around the sphered outer raceway; a pinched outer ring removes the alignment capacity the bearing was selected for.
Typical equipment & failure modes
Common applications
- steel-mill and heavy crusher main shafts
- mining shovel and dragline swing shafts
- cement-rotary-kiln support and trunnion rolls
- large SAG/ball-mill trunnion and pinion shafts
Known failure patterns
- raceway spalling at the roller ends when misalignment or deflection concentrates the line contact
- machined EM cage wear from inadequate oil film at the cage-guiding surfaces
- roller-end smearing during skidding starts under light load and high viscosity grease
- hard-particle indentation through the open arrangement in dusty mining duty
- false brinelling on stopped machines exposed to screen or crusher vibration
Selection pitfalls — read before you substitute
- At 710 mm bore 232/710BK 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.
- K and K30 are different tapers — K is 1:12 and K30 is 1:30 on the wide series; an adapter sleeve for one will not mount the other 710 mm bearing, and drive-up procedures differ.
- Do not confuse EA and EM at the same number: 232/710BK carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 710×1280 mm envelope is identical.
- Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 18100 kN rating no longer applies.
- Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 18100 kN rating no longer applies.
- The 18100/32500 kN ratings, 1200 kN Pu and 2470000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 232/710BK (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 232/710BK?
232/710BK is an NTN double-row spherical roller bearing to ISO 15: 710 mm bore, 1280 mm OD and 450 mm width (27.953 × 50.394 × 17.717 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 18100 kN, C0 32500 kN, Pu 1200 kN, grease limiting speed 200 r/min, oil 260 r/min, mass about 2470000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore.
What is the difference between the K/K30 tapered bore and the cylindrical bore versions?
K denotes a 1:12 tapered bore. 232/710BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 232/710B.
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. 232/710BK is the basic execution.
What do D1 and W33 mean on 232/710BK?
232/710BK 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 232/710BK 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 — 18100 kN C / 32500 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.