24176BK30 bearing: complete specifications & equivalents
The 24176BK30 is a ISO 15 radial bearing sized 380 x 620 x 243 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 380 mm |
| Outer diameter D | 620 mm |
| Width B | 243 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 5350 kN |
| Basic static load rating C0 | 9650 kN |
| Fatigue load limit Pu | 570 kN |
| Limiting speed (mechanical) | 450 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 287000 g |
| Manufacturer designation | NTN 24176BK30 |
| 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 | 14.961 in |
|---|---|
| Outer diameter D | 24.409 in |
| Width B | 9.567 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 120 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) | 20 of 32 |
| Bore above smallest 24100-series size | 280 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 24176B | 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 24176B — 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 24176BK30 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, 24176BK30 denotes the 380 mm bore spherical roller bearing (5350 kN C / 9650 kN C0) in the 24100 series, the self-aligning choice for heavy combined load. The leading digits are the ISO 15 dimension series (24100 series); the bore code resolves to 380 mm (two-digit code ×5, with the 00–03 exception table), and 620 mm OD / 243 mm width follow the general plan. The bearing accepts predominantly radial load with a moderate axial share, but is not a pure thrust bearing: sustained axial-only load skids the unloaded row and damages the basic cage. 380 mm bore is 14.961 in and 620 mm OD is 24.409 in; the ISO 15 envelope swaps between brands, but the 5350/9650 kN ratings and cage design are NTN 2203E values. 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
- pressed EA cage fatigue under sustained vibration when minimum load is not maintained
- roller-end smearing during skidding starts under light load and high viscosity grease
- 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 380 mm bore 24176BK30 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.
- Do not confuse EA and EM at the same number: 24176BK30 carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 380×620 mm envelope is identical.
- Do not confuse EA and EM at the same number: 24176BK30 carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 380×620 mm envelope is identical.
- Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 450 r/min grease rating is lost to abrasive wear long before fatigue.
- Never substitute 24176BK30 by envelope alone: the 9650 kN C0 and 570 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.
- The 5350/9650 kN ratings, 570 kN Pu and 287000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 24176BK30 (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 24176BK30?
24176BK30 is an NTN double-row spherical roller bearing to ISO 15: 380 mm bore, 620 mm OD and 243 mm width (14.961 × 24.409 × 9.567 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 5350 kN, C0 9650 kN, Pu 570 kN, grease limiting speed 450 r/min, oil 590 r/min, mass about 287000 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). 24176BK30 mounts on a matching adapter or withdrawal sleeve on a plain 380 mm shaft and is driven up to a measured radial clearance; the cylindrical-bore counterpart is 24176B.
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. 24176BK30 is the basic execution.
What do D1 and W33 mean on 24176BK30?
24176BK30 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 24176BK30 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 — 5350 kN C / 9650 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.