240-950BK30 bearing: complete specifications & equivalents
The 240-950BK30 is a ISO 15 radial bearing sized 950 x 1360 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 | 950 mm |
| Outer diameter D | 1360 mm |
| Width B | 412 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 17200 kN |
| Basic static load rating C0 | 40000 kN |
| Fatigue load limit Pu | 1780 kN |
| Limiting speed (mechanical) | 160 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1940000 g |
| Manufacturer designation | NTN 240/950BK30 |
| 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 & 24000-series range
| Bore d | 37.402 in |
|---|---|
| Outer diameter D | 53.543 in |
| Width B | 16.22 in |
| ISO bore code | 40 |
| Radial section height (D−d)/2 | 205 mm |
| Smallest bore in 24000-series | 65 mm |
| Largest outer diameter in 24000-series | 1580 mm |
| Width range across 24000-series | 35–462 mm |
| Bore position in 24000-series (smallest first) | 39 of 42 |
| Bore above smallest 24000-series size | 885 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 240-950B | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 24000-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 240-950B — 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 240-950BK30 model number is decoded
240/950BK30 is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 950×1360×412 mm to ISO 15, with pressed-steel cage (standard execution). On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (K30), lubrication feature (none); 240/950BK30 is assembled exactly in that order. The 205.0 mm radial section over the 950 mm bore carries two roller rows; capacity per millimetre of bore is about 18.1 kN/mm, among the highest of rolling bearings for the ISO 15 envelope. With about 18.1 kN of C per millimetre of the 950 mm bore, 240/950BK30 screens interchange candidates quickly — then verify cage (EA/EM), bore (K/K30) and lubrication feature (D1/W33) suffixes. On vibrating-duty shafts verify the radial clearance class and cage choice at order time; the open 240/950BK30 leaves sealing and the C3/C4 clearance decision to the application drawing.
Typical equipment & failure modes
Common applications
- offshore and marine propulsion shaftlines
- large wind-turbine main-shaft arrangements
- steel-mill and heavy crusher main shafts
- mining shovel and dragline swing 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
- sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path
- fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient
- hard-particle indentation through the open arrangement in dusty mining duty
Selection pitfalls — read before you substitute
- At 950 mm bore 240/950BK30 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.
- The two roller rows must share load equally — a tilted spacer or unequal abutment on the 412 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.
- The 1:30 tapered bore is the only difference from the cylindrical-bore 240/950B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.
- 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.
- The 1:30 tapered bore is the only difference from the cylindrical-bore 240/950B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.
- The 17200/40000 kN ratings, 1780 kN Pu and 1940000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/950BK30 (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 240/950BK30?
240/950BK30 is an NTN double-row spherical roller bearing to ISO 15: 950 mm bore, 1360 mm OD and 412 mm width (37.402 × 53.543 × 16.22 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 17200 kN, C0 40000 kN, Pu 1780 kN, grease limiting speed 160 r/min, oil 210 r/min, mass about 1940000 g. It is open, with pressed-steel cage (standard execution) and a 1:30 tapered bore.
What is the difference between the K/K30 tapered bore and the cylindrical bore versions?
K30 denotes a 1:30 tapered bore (the wide 24000 series). 240/950BK30 mounts on a matching adapter or withdrawal sleeve on a plain 950 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 240/950B.
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. 240/950BK30 is the basic execution.
What do D1 and W33 mean on 240/950BK30?
240/950BK30 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 240/950BK30 take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24000 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 17200 kN C / 40000 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.