23272BK bearing: complete specifications & equivalents
The 23272BK is a ISO 15 radial bearing sized 360 x 650 x 232 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 360 mm |
| Outer diameter D | 650 mm |
| Width B | 232 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 5400 kN |
| Basic static load rating C0 | 8700 kN |
| Fatigue load limit Pu | 620 kN |
| Limiting speed (mechanical) | 450 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 329000 g |
| Manufacturer designation | NTN 23272BK |
| 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 | 14.173 in |
|---|---|
| Outer diameter D | 25.591 in |
| Width B | 9.134 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 145 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) | 20 of 34 |
| Bore above smallest 23200-series size | 270 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 23272B | 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 23272B — 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 23272BK model number is decoded
23272BK belongs to the 23200 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 (23200 series); the bore code resolves to 360 mm (two-digit code ×5, with the 00–03 exception table), and 650 mm OD / 232 mm width follow the general plan. Pu 620 kN is the catalogue fatigue load limit for 23272BK, used in the adjusted-life equation at contaminated or partial-film conditions typical of mining and vibrating duty. The 145.0 mm section height hosts the spherical roller geometry; shaft and housing fillet radii must clear the chamfer table so the 232 mm-wide ring seats fully on both sides. Never mount 23272BK 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 650 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
- pressed EA cage fatigue under sustained vibration when minimum load is not maintained
- micro-pitting when the EHL film is thinner than the raceway composite roughness
- 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 360 mm bore 23272BK 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.
- 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.
- Minimum load must be maintained even at rest under vibration: an unloaded 23272BK on a stopped screen false-brinells; parking brakes and shaker isolation both matter.
- Oil relubrication toward 590 r/min needs drain and level design; flooding the 232 mm cavity churns heat through the heavy roller set and cage despite the higher oil speed figure.
- The D1/W33 groove only helps if the housing has a matching grease passage; mounting a grooved 23272BK in a solid block with no port wastes the feature and leaves the centre rows under-lubricated.
- The 5400/8700 kN ratings, 620 kN Pu and 329000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 23272BK (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 23272BK?
23272BK is an NTN double-row spherical roller bearing to ISO 15: 360 mm bore, 650 mm OD and 232 mm width (14.173 × 25.591 × 9.134 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 5400 kN, C0 8700 kN, Pu 620 kN, grease limiting speed 450 r/min, oil 590 r/min, mass about 329000 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. 23272BK 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 23272B.
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. 23272BK is the basic execution.
What do D1 and W33 mean on 23272BK?
23272BK 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 23272BK 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 — 5400 kN C / 8700 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.