240-1120BK30 bearing: complete specifications & equivalents
The 240-1120BK30 is a ISO 15 radial bearing sized 1120 x 1580 x 462 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 | 462 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 21700 kN |
| Basic static load rating C0 | 52500 kN |
| Fatigue load limit Pu | 2230 kN |
| Limiting speed (mechanical) | 120 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2840000 g |
| Manufacturer designation | NTN 240/1120BK30 |
| 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 | 44.094 in |
|---|---|
| Outer diameter D | 62.205 in |
| Width B | 18.189 in |
| ISO bore code | 40 |
| Radial section height (D−d)/2 | 230 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) | 42 of 42 |
| Bore above smallest 24000-series size | 1055 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 240-1120B | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 24000-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 240-1120B — 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 240-1120BK30 model number is decoded
240/1120BK30 belongs to the 24000 series of NTN spherical rollers: self-aligning, high radial capacity, moderate axial load in either direction. Reading the full code: the number gives the 1120×1580 mm envelope, — names the cage/capacity execution, K30 marks the 1:30 tapered bore for sleeve mounting, and plain outer ring (no D1/W33 groove) completes the order number. Suffix reading on 240/1120BK30: the bare number is the standard open execution; K30 marks the 1:30 tapered bore of the wide series; B marks the standard large-bore internal design on slash-size 230–232 series; quote the full code because each suffix is a distinct article. Catalogue mass 2840000 g (2840.00 kg) for the 1120×1580×462 mm execution includes the basic cage and both roller rows; shaft and housing shoulders must support that ring squarely. Never mount 240/1120BK30 by striking the outer ring through the roller set; drive through ring faces (or the adapter sleeve nut) and support the ring square to avoid brinelling the 1580 mm race.
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
- 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
- sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path
- 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 1120 mm bore 240/1120BK30 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 1120 mm bearing, and drive-up procedures differ.
- Never substitute 240/1120BK30 by envelope alone: the 52500 kN C0 and 2230 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.
- 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 two roller rows must share load equally — a tilted spacer or unequal abutment on the 462 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.
- The 21700/52500 kN ratings, 2230 kN Pu and 2840000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 240/1120BK30 (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 240/1120BK30?
240/1120BK30 is an NTN double-row spherical roller bearing to ISO 15: 1120 mm bore, 1580 mm OD and 462 mm width (44.094 × 62.205 × 18.189 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 21700 kN, C0 52500 kN, Pu 2230 kN, grease limiting speed 120 r/min, oil 160 r/min, mass about 2840000 g. It is open, with pressed-steel cage (standard execution) and a 1:30 tapered bore.
What is the difference between the K/K30 tapered bore and the cylindrical bore versions?
K30 denotes a 1:30 tapered bore (the wide 24000 series). 240/1120BK30 mounts on a matching adapter or withdrawal sleeve on a plain 1120 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 240/1120B.
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. 240/1120BK30 is the basic execution.
What do D1 and W33 mean on 240/1120BK30?
240/1120BK30 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 240/1120BK30 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 — 21700 kN C / 52500 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.