232-500BK bearing: complete specifications & equivalents
The 232-500BK is a ISO 15 radial bearing sized 500 x 920 x 336 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 500 mm |
| Outer diameter D | 920 mm |
| Width B | 336 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 10500 kN |
| Basic static load rating C0 | 17800 kN |
| Fatigue load limit Pu | 1100 kN |
| Limiting speed (mechanical) | 310 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 971000 g |
| Manufacturer designation | NTN 232/500BK |
| 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 | 19.685 in |
|---|---|
| Outer diameter D | 36.22 in |
| Width B | 13.228 in |
| ISO bore code | 32 |
| Radial section height (D−d)/2 | 210 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) | 27 of 34 |
| Bore above smallest 23200-series size | 410 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 232-500B | 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 232-500B — 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 232-500BK model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, 232/500BK denotes the 500 mm bore spherical roller bearing (10500 kN C / 17800 kN C0) in the 23200 series, the self-aligning choice for heavy combined load. Reading the full code: the number gives the 500×920 mm envelope, — names the cage/capacity execution, K marks the 1:12 tapered bore for adapter/withdrawal-sleeve mounting, and plain outer ring (no D1/W33 groove) completes the order number. The sphered outer raceway lets the inner-ring assembly pivot, accommodating shaft deflection and housing misalignment (around 1–2° for this class; use the 2203E value for the exact series) without edge loading the rollers. Grease/oil ratio: the 310 r/min limiting value is .78 of the 400 r/min oil value; heavy 336 mm-wide cages run hot in churning grease, so quantity and groove supply both matter. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 500 mm set.
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
- 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
- fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient
- fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient
Selection pitfalls — read before you substitute
- At 500 mm bore 232/500BK 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 232/500BK 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 310 r/min grease rating is lost to abrasive wear long before fatigue.
- 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 500 mm bearing, and drive-up procedures differ.
- Minimum load must be maintained even at rest under vibration: an unloaded 232/500BK on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- The 10500/17800 kN ratings, 1100 kN Pu and 971000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 232/500BK (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 232/500BK?
232/500BK is an NTN double-row spherical roller bearing to ISO 15: 500 mm bore, 920 mm OD and 336 mm width (19.685 × 36.22 × 13.228 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 10500 kN, C0 17800 kN, Pu 1100 kN, grease limiting speed 310 r/min, oil 400 r/min, mass about 971000 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. 232/500BK 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 232/500B.
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. 232/500BK is the basic execution.
What do D1 and W33 mean on 232/500BK?
232/500BK 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 232/500BK 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 — 10500 kN C / 17800 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.