81152-M bearing: complete specifications & equivalents
The 81152-M is a ISO 104 radial bearing sized 260 x 320 x 45 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 260 mm |
| Outer diameter D | 320 mm |
| Width B | 45 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 490 kN |
| Basic static load rating C0 | 2600 kN |
| Fatigue load limit Pu | 200 kN |
| Reference speed (thermal) | 530 rpm |
| Limiting speed (mechanical) | 1100 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 9100 g |
| Manufacturer designation | 81152 M |
| Standard | ISO 104 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & 81100-series range
| Bore d | 10.236 in |
|---|---|
| Outer diameter D | 12.598 in |
| Width B | 1.772 in |
| ISO bore code | 52 |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in 81100-series | 15 mm |
| Largest outer diameter in 81100-series | 400 mm |
| Width range across 81100-series | 9–63 mm |
| Bore position in 81100-series (smallest first) | 31 of 34 |
| Bore above smallest 81100-series size | 245 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the 81152-M model number is decoded
The light 811 series bearing 81152 M carries pure axial load at low to moderate speed: 490 kN dynamic and 2600 kN static across a 260×320 mm washer pair, 45 mm overall height. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81152 M sits in the light 811 series. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.54. The 9100 g mass and 45 mm axial height sit between 260 and 320 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.
Typical equipment & failure modes
Common applications
- extruder and injection press screw thrust blocks at low speed
- rolling-mill screwdown mechanisms and press adjusters
- slewing and turntable pivots with predominantly axial force
- crane hook crossheads carrying pure hook thrust while the hook swivels
Known failure patterns
- cage wear from rollers being dragged through unloaded zones under fluctuating thrust
- housing-washer rotation scored into an unmachined or loose seating face
- oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips
- false brinelling and rust-red witness marks on standby machines under external vibration
- roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)
Selection pitfalls — read before you substitute
- At 260 mm bore the 9.1 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.
- Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.
- Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81152 M need different minimum load and lubrication despite the shared 260×320 mm outline.
- The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81152 M size.
- the 530 r/min reference speed is the thermal criterion under load, the 1,100 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.
- The 490/2600 kN ratings and 9100 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only.
Frequently asked questions
Are the washers of 81152 M separable?
Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height.
Can a thrust ball bearing replace the 81152 M?
They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting.
What ruins a 81152 M in service?
Unloaded running below factor A 0.54 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,100 r/min limiting.
Which dimensions does the 81152 M have?
A 81152 M measures 260 mm bore × 320 mm outside diameter × 45 mm width (10.236 × 12.598 × 1.772 in). From SKF catalogue PUB BU/P1 17000: dynamic C 490 kN, static C0 2600 kN, fatigue limit Pu 200 kN, reference speed 530 r/min, limiting speed 1,100 r/min, mass about 9100 g. Raceway diameters Ea 268 mm / Eb 316 mm and minimum load factor A 0.54 guide the seat design.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings on 2026-09-27. Read our editorial & correction policy.