240-630B bearing: complete specifications & equivalents
The 240-630B is a ISO 15 radial bearing sized 630 x 920 x 290 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 | 920 mm |
| Width B | 290 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 8400 kN |
| Basic static load rating C0 | 17900 kN |
| Fatigue load limit Pu | 915 kN |
| Limiting speed (mechanical) | 270 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 657000 g |
| Manufacturer designation | NTN 240/630B |
| 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 | 24.803 in |
|---|---|
| Outer diameter D | 36.22 in |
| Width B | 11.417 in |
| ISO bore code | 40 |
| Radial section height (D−d)/2 | 145 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) | 32 of 42 |
| Bore above smallest 24000-series size | 565 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 240-630BK30 | 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 240-630BK30 (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 240-630B model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, 240/630B denotes the 630 mm bore spherical roller bearing (8400 kN C / 17900 kN C0) in the 24000 series, the self-aligning choice for heavy combined load. Numbering ties 240/630B to its envelope and execution: same-number EA versus EM or plain variants share the 630 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Pu 915 kN is the catalogue fatigue load limit for 240/630B, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. The 145.0 mm section height hosts the spherical roller geometry; shaft and housing fillet radii must clear the chamfer table so the 290 mm-wide ring seats fully on both sides. On vibrating-duty shafts verify the radial clearance class and cage choice at order time; the open 240/630B 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
- 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
- rolling-contact fatigue after the catalogue L10 life at the actual load
- fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient
Selection pitfalls — read before you substitute
- At 630 mm bore 240/630B 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.
- 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 630 mm bearing, and drive-up procedures differ.
- Never substitute 240/630B by envelope alone: the 17900 kN C0 and 915 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.
- Never substitute 240/630B by envelope alone: the 17900 kN C0 and 915 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 240/630B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- The 8400/17900 kN ratings, 915 kN Pu and 657000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/630B (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 240/630B?
240/630B is an NTN double-row spherical roller bearing to ISO 15: 630 mm bore, 920 mm OD and 290 mm width (24.803 × 36.22 × 11.417 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 8400 kN, C0 17900 kN, Pu 915 kN, grease limiting speed 270 r/min, oil 350 r/min, mass about 657000 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?
240/630B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 240/630BK30 (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. 240/630B is the basic execution.
What do D1 and W33 mean on 240/630B?
240/630B 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 240/630B 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 — 8400 kN C / 17900 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.