240-950B bearing: complete specifications & equivalents
The 240-950B 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 | 1970000 g |
| Manufacturer designation | NTN 240/950B |
| 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 |
|---|---|---|---|
| 240-950BK30 | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 24000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 240-950BK30 (K/K30 sleeve or tapered-seat mounting). 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 240-950B model number is decoded
240/950B belongs to the 24000 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. Numbering ties 240/950B to its envelope and execution: same-number EA versus EM or plain variants share the 950 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. NTN prints two speeds for 240/950B: 160 r/min grease and 210 r/min oil — the gap of 50 r/min reflects oil cooling of the heavy roller set. Pu 1780 kN against C0 40000 kN anchors the contamination derating; for dirty mining duty the adjusted life of 240/950B moves with cleanliness far more than with small C variations. 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
- large wind-turbine main-shaft arrangements
- steel-mill and heavy crusher main shafts
- mining shovel and dragline swing shafts
- cement-rotary-kiln support and trunnion rolls
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
- hard-particle indentation through the open arrangement in dusty mining duty
- water-induced pitting in washdown or outdoor duty without effective external seals
Selection pitfalls — read before you substitute
- At 950 mm bore 240/950B 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.
- 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 D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 240/950B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- Do not confuse EA and EM at the same number: 240/950B carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 950×1360 mm envelope is identical.
- Oil relubrication toward 210 r/min needs drain and level design; flooding the 412 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.
- The 17200/40000 kN ratings, 1780 kN Pu and 1970000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/950B (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 240/950B?
240/950B 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 1970000 g. It is open, with pressed-steel cage (standard execution).
What is the difference between the K/K30 tapered bore and the cylindrical bore versions?
240/950B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 240/950BK30 (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting.
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. 240/950B is the basic execution.
What do D1 and W33 mean on 240/950B?
240/950B 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 240/950B 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.