230-1120BK bearing: complete specifications & equivalents
The 230-1120BK is a ISO 15 radial bearing sized 1120 x 1580 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 | 1120 mm |
| Outer diameter D | 1580 mm |
| Width B | 345 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 17400 kN |
| Basic static load rating C0 | 39000 kN |
| Fatigue load limit Pu | 2310 kN |
| Limiting speed (mechanical) | 150 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2090000 g |
| Manufacturer designation | NTN 230/1120BK |
| 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 | 44.094 in |
|---|---|
| Outer diameter D | 62.205 in |
| Width B | 13.583 in |
| ISO bore code | 30 |
| Radial section height (D−d)/2 | 230 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) | 46 of 46 |
| Bore above smallest 23000-series size | 1050 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 230-1120B | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23000-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 230-1120B — 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 230-1120BK model number is decoded
230/1120BK belongs to the 23000 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. The leading digits are the ISO 15 dimension series (23000 series); the bore code resolves to 1120 mm (two-digit code ×5, with the 00–03 exception table), and 1580 mm OD / 345 mm width follow the general plan. Pu 2310 kN is the catalogue fatigue load limit for 230/1120BK, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. Selection: the C0/C ratio of 2.24 (39000/17400 kN) reflects the heavy static and shock proportioning of 230/1120BK; size the equivalent load at the required L10 with shock factor for the application. 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
- steel-mill and heavy crusher main shafts
- mining shovel and dragline swing shafts
- cement-rotary-kiln support and trunnion rolls
- large SAG/ball-mill trunnion and pinion 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
- hard-particle indentation through the open arrangement in dusty mining duty
- false brinelling on stopped machines exposed to screen or crusher vibration
Selection pitfalls — read before you substitute
- At 1120 mm bore 230/1120BK 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 1:12 tapered bore is the only difference from the cylindrical-bore 230/1120B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.
- 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 1120 mm bearing, and drive-up procedures differ.
- The 1:12 tapered bore is the only difference from the cylindrical-bore 230/1120B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 230/1120BK in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- The 17400/39000 kN ratings, 2310 kN Pu and 2090000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 230/1120BK (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 230/1120BK?
230/1120BK is an NTN double-row spherical roller bearing to ISO 15: 1120 mm bore, 1580 mm OD and 345 mm width (44.094 × 62.205 × 13.583 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 17400 kN, C0 39000 kN, Pu 2310 kN, grease limiting speed 150 r/min, oil 190 r/min, mass about 2090000 g. It is open, with pressed-steel cage (standard execution) and a 1:12 tapered bore.
What is the difference between the K/K30 tapered bore and the cylindrical bore versions?
K denotes a 1:12 tapered bore. 230/1120BK mounts on an adapter sleeve (or tapered shaft seat) and is driven up to the specified residual clearance; its cylindrical-bore counterpart in the same envelope and ratings is 230/1120B.
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. 230/1120BK is the basic execution.
What do D1 and W33 mean on 230/1120BK?
230/1120BK 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 230/1120BK 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 — 17400 kN C / 39000 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.