230-950BK bearing: complete specifications & equivalents
The 230-950BK is a ISO 15 radial bearing sized 950 x 1360 x 300 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 950 mm |
| Outer diameter D | 1360 mm |
| Width B | 300 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 12800 kN |
| Basic static load rating C0 | 28400 kN |
| Fatigue load limit Pu | 1750 kN |
| Limiting speed (mechanical) | 180 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1380000 g |
| Manufacturer designation | NTN 230/950BK |
| 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 & 23000-series range
| Bore d | 37.402 in |
|---|---|
| Outer diameter D | 53.543 in |
| Width B | 11.811 in |
| ISO bore code | 30 |
| Radial section height (D−d)/2 | 205 mm |
| Smallest bore in 23000-series | 70 mm |
| Largest outer diameter in 23000-series | 1580 mm |
| Width range across 23000-series | 27–345 mm |
| Bore position in 23000-series (smallest first) | 43 of 46 |
| Bore above smallest 23000-series size | 880 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 230-950B | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 230-950B — 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 230-950BK model number is decoded
The NTN order number 230/950BK identifies a 950×1360×300 mm (37.402 × 53.543 × 11.811 in) spherical roller bearing, 1:12 tapered bore (K), to the ISO 15 boundary plan. On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (K), lubrication feature (none); 230/950BK is assembled exactly in that order. 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. Catalogue mass 1380000 g (1380.00 kg) for the 950×1360×300 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. 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 950 mm set.
Typical equipment & failure modes
Common applications
- mining shovel and dragline swing shafts
- cement-rotary-kiln support and trunnion rolls
- large SAG/ball-mill trunnion and pinion shafts
- heavy vibrating screens and grizzly feeders
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
- micro-pitting when the EHL film is thinner than the raceway composite roughness
- 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 950 mm bore 230/950BK 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.
- Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 12800 kN rating no longer applies.
- Minimum load must be maintained even at rest under vibration: an unloaded 230/950BK on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- Adapter-sleeve mounting requires the correct sleeve series and locknut for the 950 mm shaft; a sleeve sized to bore alone ignores thread, width and the oil-injection option on large K30 seats.
- Minimum load must be maintained even at rest under vibration: an unloaded 230/950BK on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- The 12800/28400 kN ratings, 1750 kN Pu and 1380000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/950BK (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 230/950BK?
230/950BK is an NTN double-row spherical roller bearing to ISO 15: 950 mm bore, 1360 mm OD and 300 mm width (37.402 × 53.543 × 11.811 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 12800 kN, C0 28400 kN, Pu 1750 kN, grease limiting speed 180 r/min, oil 230 r/min, mass about 1380000 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. 230/950BK 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 230/950B.
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. 230/950BK is the basic execution.
What do D1 and W33 mean on 230/950BK?
230/950BK 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 230/950BK take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 12800 kN C / 28400 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.