239-750 bearing: complete specifications & equivalents
The 239-750 is a ISO 15 radial bearing sized 750 x 1000 x 185 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 750 mm |
| Outer diameter D | 1000 mm |
| Width B | 185 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 5600 kN |
| Basic static load rating C0 | 13000 kN |
| Fatigue load limit Pu | 990 kN |
| Limiting speed (mechanical) | 260 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 412000 g |
| Manufacturer designation | NTN 239/750 |
| 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 & 23900-series range
| Bore d | 29.528 in |
|---|---|
| Outer diameter D | 39.37 in |
| Width B | 7.283 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 125 mm |
| Smallest bore in 23900-series | 160 mm |
| Largest outer diameter in 23900-series | 1820 mm |
| Width range across 23900-series | 45–315 mm |
| Bore position in 23900-series (smallest first) | 27 of 38 |
| Bore above smallest 23900-series size | 590 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 239-750K | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same NTN 23900-series envelope, cage and ratings; this is the cylindrical-bore execution of the tapered-bore 239-750K (K/K30 sleeve or tapered-seat mounting). 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 239-750 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, 239/750 denotes the 750 mm bore spherical roller bearing (5600 kN C / 13000 kN C0) in the 23900 series, the self-aligning choice for heavy combined load. On the NTN nameplate the suffix cluster after the size reads in order: cage design (—), bore (cylindrical), lubrication feature (none); 239/750 is assembled exactly in that order. Open by design, 239/750 requires application seals and a grease or oil system; NTN vibrating-duty executions of this envelope are selected with cage and clearance choices that are separate order codes. Selection: the C0/C ratio of 2.32 (13000/5600 kN) reflects the heavy static and shock proportioning of 239/750; size the equivalent load at the required L10 with shock factor for the application. Fillet radii on shaft and housing must clear the ring chamfers of the 185 mm-wide set; use the NTN shoulder/withdrawal-groove table rather than copying a ball-bearing layout.
Typical equipment & failure modes
Common applications
- mining shovel and dragline swing shafts
- cement-rotary-kiln support and trunnion rolls
- large SAG/ball-mill trunnion and pinion shafts
- heavy vibrating screens and grizzly feeders
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
- hard-particle indentation through the open arrangement in dusty mining duty
- fretting corrosion between adapter sleeve and tapered bore when the drive-up is insufficient
Selection pitfalls — read before you substitute
- At 750 mm bore 239/750 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 cylindrical-bore 239/750 and its tapered-bore counterpart 239/750K share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.
- The cylindrical-bore 239/750 and its tapered-bore counterpart 239/750K share envelope and ratings but not mounting: do not order the K variant unless the drawing specifies a sleeve or tapered seat.
- Open spherical rollers swallow dust in mining duty; specify labyrinth or taconite seals externally, or the 260 r/min grease rating is lost to abrasive wear long before fatigue.
- Self-aligning does not mean unlimited misalignment: beyond the catalogue angle the outer ring's spherical travel is exhausted and the 5600 kN rating no longer applies.
- The 5600/13000 kN ratings, 990 kN Pu and 412000 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for 239/750 (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 239/750?
239/750 is an NTN double-row spherical roller bearing to ISO 15: 750 mm bore, 1000 mm OD and 185 mm width (29.528 × 39.37 × 7.283 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 5600 kN, C0 13000 kN, Pu 990 kN, grease limiting speed 260 r/min, oil 340 r/min, mass about 412000 g. It is open, with pressed-steel cage (standard execution).
What is the difference between the K/K30 tapered bore and the cylindrical bore versions?
239/750 has a cylindrical bore and mounts directly on a machined shaft seat. Its tapered-bore counterpart is 239/750K (K = 1:12, or K30 = 1:30 on the wide series), intended for adapter/withdrawal-sleeve mounting.
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. 239/750 is the basic execution.
What do D1 and W33 mean on 239/750?
239/750 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 239/750 take?
The sphered outer raceway compensates static and dynamic misalignment in the order of 1–2° (verify the exact 2203E figure for the 23900 series); beyond that, load concentrates on one roller row. Load is predominantly radial with a moderate axial share in either direction — 5600 kN C / 13000 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.