231-710B bearing: complete specifications & equivalents
The 231-710B is a ISO 15 radial bearing sized 710 x 1150 x 345 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 710 mm |
| Outer diameter D | 1150 mm |
| Width B | 345 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 13000 kN |
| Basic static load rating C0 | 24900 kN |
| Fatigue load limit Pu | 1470 kN |
| Limiting speed (mechanical) | 220 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1420000 g |
| Manufacturer designation | NTN 231/710B |
| 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 & 23100-series range
| Bore d | 27.953 in |
|---|---|
| Outer diameter D | 45.276 in |
| Width B | 13.583 in |
| ISO bore code | 31 |
| Radial section height (D−d)/2 | 220 mm |
| Smallest bore in 23100-series | 100 mm |
| Largest outer diameter in 23100-series | 1420 mm |
| Width range across 23100-series | 52–412 mm |
| Bore position in 23100-series (smallest first) | 32 of 36 |
| Bore above smallest 23100-series size | 610 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 231-710BK | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23100-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 231-710BK (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 231-710B model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, 231/710B denotes the 710 mm bore spherical roller bearing (13000 kN C / 24900 kN C0) in the 23100 series, the self-aligning choice for heavy combined load. The leading digits are the ISO 15 dimension series (23100 series); the bore code resolves to 710 mm (two-digit code ×5, with the 00–03 exception table), and 1150 mm OD / 345 mm width follow the general plan. 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. Pu 1470 kN against C0 24900 kN anchors the contamination derating; for dirty mining duty the adjusted life of 231/710B 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
- heavy vibrating screens and grizzly feeders
- offshore and marine propulsion shaftlines
- large wind-turbine main-shaft arrangements
- steel-mill and heavy crusher main 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
- micro-pitting when the EHL film is thinner than the raceway composite roughness
- false brinelling on stopped machines exposed to screen or crusher vibration
- water-induced pitting in washdown or outdoor duty without effective external seals
Selection pitfalls — read before you substitute
- At 710 mm bore 231/710B 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.
- Never substitute 231/710B by envelope alone: the 24900 kN C0 and 1470 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.
- The cylindrical-bore 231/710B and its tapered-bore counterpart 231/710BK share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 231/710B in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- Minimum load must be maintained even at rest under vibration: an unloaded 231/710B on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- The 13000/24900 kN ratings, 1470 kN Pu and 1420000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 231/710B (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 231/710B?
231/710B is an NTN double-row spherical roller bearing to ISO 15: 710 mm bore, 1150 mm OD and 345 mm width (27.953 × 45.276 × 13.583 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 13000 kN, C0 24900 kN, Pu 1470 kN, grease limiting speed 220 r/min, oil 280 r/min, mass about 1420000 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?
231/710B has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 231/710BK (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. 231/710B is the basic execution.
What do D1 and W33 mean on 231/710B?
231/710B 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 231/710B take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 13000 kN C / 24900 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.