230-900B bearing: complete specifications & equivalents
The 230-900B is a ISO 15 radial bearing sized 900 x 1280 x 280 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 900 mm |
| Outer diameter D | 1280 mm |
| Width B | 280 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 11400 kN |
| Basic static load rating C0 | 24700 kN |
| Fatigue load limit Pu | 1580 kN |
| Limiting speed (mechanical) | 190 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1170000 g |
| Manufacturer designation | NTN 230/900B |
| 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 | 35.433 in |
|---|---|
| Outer diameter D | 50.394 in |
| Width B | 11.024 in |
| ISO bore code | 30 |
| Radial section height (D−d)/2 | 190 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) | 42 of 46 |
| Bore above smallest 23000-series size | 830 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 230-900BK | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23000-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 230-900BK (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 230-900B model number is decoded
NTN lists 230/900B with a cylindrical bore and plain outer ring (no D1/W33 groove): 900 mm bore, 1280 mm OD, 280 mm width, rated 190 r/min on grease. Numbering ties 230/900B to its envelope and execution: same-number EA versus EM or plain variants share the 900 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. At 11400 kN C and 1170000 g mass the 23000 series part is built for shock and vibration; the 280 mm-wide ring needs square abutments to keep both rows equally loaded. With about 12.7 kN of C per millimetre of the 900 mm bore, 230/900B screens interchange candidates quickly — then verify cage (EA/EM), bore (K/K30) and lubrication feature (D1/W33) suffixes. Fillet radii on shaft and housing must clear the ring chamfers of the 280 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.
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
- lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply
- machined EM cage wear from inadequate oil film at the cage-guiding surfaces
- roller-end smearing during skidding starts under light load and high viscosity grease
- brinelling from static overload or a hammer blow during sleeve mounting
- asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range
Selection pitfalls — read before you substitute
- At 900 mm bore 230/900B 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 280 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 230/900B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 11400 kN rating no longer applies.
- Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 190 r/min grease rating is lost to abrasive wear long before fatigue.
- The 11400/24700 kN ratings, 1580 kN Pu and 1170000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/900B (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 230/900B?
230/900B is an NTN double-row spherical roller bearing to ISO 15: 900 mm bore, 1280 mm OD and 280 mm width (35.433 × 50.394 × 11.024 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 11400 kN, C0 24700 kN, Pu 1580 kN, grease limiting speed 190 r/min, oil 250 r/min, mass about 1170000 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?
230/900B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 230/900BK (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. 230/900B is the basic execution.
What do D1 and W33 mean on 230/900B?
230/900B 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 230/900B 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 — 11400 kN C / 24700 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.