24180BK30 bearing: complete specifications & equivalents
The 24180BK30 is a ISO 15 radial bearing sized 400 x 650 x 250 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 400 mm |
| Outer diameter D | 650 mm |
| Width B | 250 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 5650 kN |
| Basic static load rating C0 | 10300 kN |
| Fatigue load limit Pu | 585 kN |
| Limiting speed (mechanical) | 430 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 324000 g |
| Manufacturer designation | NTN 24180BK30 |
| 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 & 24100-series range
| Bore d | 15.748 in |
|---|---|
| Outer diameter D | 25.591 in |
| Width B | 9.843 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 125 mm |
| Smallest bore in 24100-series | 100 mm |
| Largest outer diameter in 24100-series | 1150 mm |
| Width range across 24100-series | 65–438 mm |
| Bore position in 24100-series (smallest first) | 21 of 32 |
| Bore above smallest 24100-series size | 300 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 24180B | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 24100-series envelope, cage and ratings; this is the tapered-bore execution (K30, 1:30) of the cylindrical-bore 24180B — 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 24180BK30 model number is decoded
24180BK30 belongs to the 24100 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 (24100 series); the bore code resolves to 400 mm (two-digit code ×5, with the 00–03 exception table), and 650 mm OD / 250 mm width follow the general plan. The plain outer ring (no D1/W33 groove) makes relubrication part of the design: fresh grease reaches the rolling elements through the outer-ring feature rather than relying solely on end-side packing. Equivalent-load planning keeps a radial plus moderate axial combination on 24180BK30; if the axial component dominates, pair with a thrust bearing rather than running one roller row unloaded. After mounting on a tapered seat, lock the nut and re-check clearance after a short running-in period, because sleeve seating and ring lift-off can change the residual clearance of the 400 mm set.
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
- lubricant starvation at the centre rib area when the D1/W33 groove is not connected to a relubrication supply
- cage damage when a mounting force is applied through the roller set instead of the ring face
- sliding wear and heat when relubrication intervals ignore the groove (D1/W33) supply path
- asymmetric wear on the two roller rows from sustained angular misalignment beyond the self-aligning range
- rolling-contact fatigue after the catalogue L10 life at the actual load
Selection pitfalls — read before you substitute
- At 400 mm bore 24180BK30 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 1:30 tapered bore is the only difference from the cylindrical-bore 24180B: 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 24180BK30 in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- The two roller rows must share load equally — a tilted spacer or unequal abutment on the 250 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.
- 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 400 mm bearing, and drive-up procedures differ.
- The 5650/10300 kN ratings, 585 kN Pu and 324000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 24180BK30 (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 24180BK30?
24180BK30 is an NTN double-row spherical roller bearing to ISO 15: 400 mm bore, 650 mm OD and 250 mm width (15.748 × 25.591 × 9.843 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 5650 kN, C0 10300 kN, Pu 585 kN, grease limiting speed 430 r/min, oil 560 r/min, mass about 324000 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 24100 series). 24180BK30 mounts on a matching adapter or withdrawal sleeve on a plain 400 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 24180B.
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. 24180BK30 is the basic execution.
What do D1 and W33 mean on 24180BK30?
24180BK30 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 24180BK30 take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 24100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 5650 kN C / 10300 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.