232-630BK bearing: complete specifications & equivalents
The 232-630BK is a ISO 15 radial bearing sized 630 x 1150 x 412 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 630 mm |
| Outer diameter D | 1150 mm |
| Width B | 412 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 15200 kN |
| Basic static load rating C0 | 26800 kN |
| Fatigue load limit Pu | 1540 kN |
| Limiting speed (mechanical) | 230 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1840000 g |
| Manufacturer designation | NTN 232/630BK |
| 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 | 24.803 in |
|---|---|
| Outer diameter D | 45.276 in |
| Width B | 16.22 in |
| ISO bore code | 32 |
| Radial section height (D−d)/2 | 260 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) | 31 of 34 |
| Bore above smallest 23200-series size | 540 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 232-630B | 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 232-630B — 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 232-630BK model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, 232/630BK denotes the 630 mm bore spherical roller bearing (15200 kN C / 26800 kN C0) in the 23200 series, the self-aligning choice for heavy combined load. The leading digits are the ISO 15 dimension series (23200 series); the bore code resolves to 630 mm (two-digit code ×5, with the 00–03 exception table), and 1150 mm OD / 412 mm width follow the general plan. Pu 1540 kN is the catalogue fatigue load limit for 232/630BK, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. Catalogue mass 1840000 g (1840.00 kg) for the 630×1150×412 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. Mount 232/630BK on its adapter or withdrawal sleeve on the 630 mm plain shaft: oil the sleeve, fit the lock nut, drive up to the NTN-specified residual clearance (or use oil injection on large seats), then lock the tab washer.
Typical equipment & failure modes
Common applications
- cement-rotary-kiln support and trunnion rolls
- large SAG/ball-mill trunnion and pinion shafts
- heavy vibrating screens and grizzly feeders
- offshore and marine propulsion shaftlines
Known failure patterns
- raceway spalling at the roller ends when misalignment or deflection concentrates the line contact
- cage damage when a mounting force is applied through the roller set instead of the ring face
- sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path
- water-induced pitting in washdown or outdoor duty without effective external seals
- rolling-contact fatigue after the catalogue L10 life at the actual load
Selection pitfalls — read before you substitute
- At 630 mm bore 232/630BK 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.
- Never substitute 232/630BK by envelope alone: the 26800 kN C0 and 1540 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.
- Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 230 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 232/630BK 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 232/630BK in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- The 15200/26800 kN ratings, 1540 kN Pu and 1840000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 232/630BK (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 232/630BK?
232/630BK is an NTN double-row spherical roller bearing to ISO 15: 630 mm bore, 1150 mm OD and 412 mm width (24.803 × 45.276 × 16.22 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 15200 kN, C0 26800 kN, Pu 1540 kN, grease limiting speed 230 r/min, oil 300 r/min, mass about 1840000 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. 232/630BK 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 232/630B.
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. 232/630BK is the basic execution.
What do D1 and W33 mean on 232/630BK?
232/630BK 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 232/630BK 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 — 15200 kN C / 26800 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.