23276BK bearing: complete specifications & equivalents
The 23276BK is a ISO 15 radial bearing sized 380 x 680 x 240 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 | 680 mm |
| Width B | 240 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 5800 kN |
| Basic static load rating C0 | 9650 kN |
| Fatigue load limit Pu | 665 kN |
| Limiting speed (mechanical) | 430 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 369000 g |
| Manufacturer designation | NTN 23276BK |
| 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 & 23200-series range
| Bore d | 14.961 in |
|---|---|
| Outer diameter D | 26.772 in |
| Width B | 9.449 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 150 mm |
| Smallest bore in 23200-series | 90 mm |
| Largest outer diameter in 23200-series | 1360 mm |
| Width range across 23200-series | 52.4–475 mm |
| Bore position in 23200-series (smallest first) | 21 of 34 |
| Bore above smallest 23200-series size | 290 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 23276B | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23200-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 23276B — 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 23276BK model number is decoded
23276BK is an NTN double-row spherical roller bearing: two rows of symmetric rollers on a sphered outer raceway, 380×680×240 mm to ISO 15, with pressed-steel cage (standard execution). Reading the full code: the number gives the 380×680 mm envelope, — names the cage/capacity execution, K marks the 1:12 tapered bore for adapter/withdrawal-sleeve mounting, and plain outer ring (no D1/W33 groove) completes the order number. The 150.0 mm radial section over the 380 mm bore carries two roller rows; capacity per millimetre of bore is about 15.3 kN/mm, among the highest of rolling bearings for the ISO 15 envelope. Pu 665 kN against C0 9650 kN anchors the contamination derating; for dirty mining duty the adjusted life of 23276BK moves with cleanliness far more than with small C variations. 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 380 mm set.
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
- 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
- water-induced pitting in washdown or outdoor duty without effective external seals
- rolling-contact fatigue after the catalogue L10 life at the actual load
Selection pitfalls — read before you substitute
- At 380 mm bore 23276BK 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.
- Minimum load must be maintained even at rest under vibration: an unloaded 23276BK on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- 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 380 mm bearing, and drive-up procedures differ.
- Never substitute 23276BK by envelope alone: the 9650 kN C0 and 665 kN Pu are specific to the NTN basic execution, and vibrating duty depends heavily on cage identity.
- The 1:12 tapered bore is the only difference from the cylindrical-bore 23276B: envelopes and ratings match, but drive-up tooling, sleeve and seat do not — never mix the two mounting methods.
- The 5800/9650 kN ratings, 665 kN Pu and 369000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 23276BK (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 23276BK?
23276BK is an NTN double-row spherical roller bearing to ISO 15: 380 mm bore, 680 mm OD and 240 mm width (14.961 × 26.772 × 9.449 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 5800 kN, C0 9650 kN, Pu 665 kN, grease limiting speed 430 r/min, oil 550 r/min, mass about 369000 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. 23276BK 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 23276B.
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. 23276BK is the basic execution.
What do D1 and W33 mean on 23276BK?
23276BK 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 23276BK take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23200 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 5800 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.