23172BK bearing: complete specifications & equivalents
The 23172BK is a ISO 15 radial bearing sized 360 x 600 x 192 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 | 600 mm |
| Width B | 192 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 4200 kN |
| Basic static load rating C0 | 7050 kN |
| Fatigue load limit Pu | 530 kN |
| Limiting speed (mechanical) | 490 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 215000 g |
| Manufacturer designation | NTN 23172BK |
| 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 & 23100-series range
| Bore d | 14.173 in |
|---|---|
| Outer diameter D | 23.622 in |
| Width B | 7.559 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 120 mm |
| Smallest bore in 23100-series | 100 mm |
| Largest outer diameter in 23100-series | 1420 mm |
| Width range across 23100-series | 52–412 mm |
| Bore position in 23100-series (smallest first) | 19 of 36 |
| Bore above smallest 23100-series size | 260 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 23172B | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23100-series envelope, cage and ratings; this is the tapered-bore execution (K, 1:12) of the cylindrical-bore 23172B — 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 23172BK model number is decoded
The NTN order number 23172BK identifies a 360×600×192 mm (14.173 × 23.622 × 7.559 in) spherical roller bearing, 1:12 tapered bore (K), to the ISO 15 boundary plan. Numbering ties 23172BK to its envelope and execution: same-number EA versus EM or plain variants share the 360 mm bore but differ in cage and sometimes mass, so they are quoted as separate articles. Suffix reading on 23172BK: the bare number is the standard open execution; K marks the 1:12 tapered bore; 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. Selection: the C0/C ratio of 1.68 (7050/4200 kN) reflects the heavy static and shock proportioning of 23172BK; size the equivalent load at the required L10 with shock factor for the application. Never mount 23172BK 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 600 mm race.
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
- cage damage when a mounting force is applied through the roller set instead of the ring face
- micro-pitting when the EHL film is thinner than the raceway composite roughness
- hard-particle indentation through the open arrangement in dusty mining duty
- false brinelling on stopped machines exposed to screen or crusher vibration
Selection pitfalls — read before you substitute
- At 360 mm bore 23172BK 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: 23172BK carries basic; swapping to the other cage execution changes mass, speed behaviour and sometimes suitability for vibration, even though the 360×600 mm envelope is identical.
- Never substitute 23172BK by envelope alone: the 7050 kN C0 and 530 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 360 mm bearing, and drive-up procedures differ.
- The two roller rows must share load equally — a tilted spacer or unequal abutment on the 192 mm-wide ring loads one row only and shows as asymmetric race polish during inspection.
- The 4200/7050 kN ratings, 530 kN Pu and 215000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 23172BK (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 23172BK?
23172BK is an NTN double-row spherical roller bearing to ISO 15: 360 mm bore, 600 mm OD and 192 mm width (14.173 × 23.622 × 7.559 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 4200 kN, C0 7050 kN, Pu 530 kN, grease limiting speed 490 r/min, oil 630 r/min, mass about 215000 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. 23172BK 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 23172B.
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. 23172BK is the basic execution.
What do D1 and W33 mean on 23172BK?
23172BK 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 23172BK take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23100 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 4200 kN C / 7050 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.