C31-1000-KMB-AOH31-1000 bearing: complete specifications & equivalents
The C31-1000-KMB-AOH31-1000 is a ISO 15 radial bearing sized 950 x 1580 x 462 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 950 mm |
| Outer diameter D | 1580 mm |
| Width B | 462 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 20400 kN |
| Basic static load rating C0 | 45500 kN |
| Fatigue load limit Pu | 2500 kN |
| Reference speed (thermal) | 220 rpm |
| Limiting speed (mechanical) | 300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 3950000 g |
| Manufacturer designation | SKF C 31/1000 KMB + AOH 31/1000 |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.2-10.3 CARB on sleeves |
| Last verified | 2026-09-29 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.2-10.3 CARB on sleeves) · extracted 2026-09-29
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.2-10.3 CARB on sleeves); 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 & carb-withdrawal-sleeve range
| Bore d | 37.402 in |
|---|---|
| Outer diameter D | 62.205 in |
| Width B | 18.189 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 315 mm |
| Smallest bore in carb-withdrawal-sleeve | 35 mm |
| Largest outer diameter in carb-withdrawal-sleeve | 1580 mm |
| Width range across carb-withdrawal-sleeve | 23–462 mm |
| Bore position in carb-withdrawal-sleeve (smallest first) | 49 of 49 |
| Bore above smallest carb-withdrawal-sleeve size | 915 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| C31 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
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 C31-1000-KMB-AOH31-1000 model number is decoded
Speed note: for C31-1000-KMB-AOH31-1000 the CARB table lists 220 r/min reference and 300 r/min limiting speed the permissible speed of the unit is bounded by the CARB bearing's own catalogue values and by the sleeve-seat interface; sleeve-mounted units run marginally cooler-balanced because the sleeve adds a thermal resistance at the 950 mm seat. Record the sleeve travel at mounting of C31-1000-KMB-AOH31-1000: the clearance set into the 1000 mm bearing today is the reference for the next re-clearance check, and travel data catches seat wear on the 950 mm shaft over the years. The unit's temp range follows the bearing: -40 to +120 °C continuous for the standard execution; cage and sleeve execution letters on C 31/1000 KMB and AOH 31/1000 must be checked against the application temperature before substitution.In SKF catalogue PUB BU/P1 17000, C31-1000-KMB-AOH31-1000 appears as bearing C 31/1000 KMB + withdrawal sleeve AOH 31/1000 — the large-size execution of the CARB non-locating principle, delivered as one assembly weighing 3950 kg.Digit by digit, C31-1000-KMB-AOH31-1000 = CARB bearing C 31/1000 KMB (1000 mm bore, 1580 mm OD, 462 mm width) + withdrawal sleeve AOH 31/1000 for the 950 mm cylindrical shaft seat; cage and tolerance letters stay with the bearing half of the designation. Why a withdrawal sleeve at 950 mm shaft: adapter-sleeve locknut forces become impractical on the 1000 mm bore; the AOH 31/1000 execution lets the fitter generate mounting interference with manageable forces and remove the unit later without damaging the seat.
Typical equipment & failure modes
Common applications
- long fan and kiln main shafts where the free end must float without thrust load
- heavy industrial gearbox layshafts used as the non-locating position
- winder and reel drums in paper and steel strip plants
- long fan and kiln main shafts where the free end must float without thrust load
Known failure patterns
- overheating from a preload set at mounting when sleeve travel overshot the catalogue clearance
- raceway spalling of the CARB bearing after the catalogue L10 life under contaminated lubrication
- overheating from a preload set at mounting when sleeve travel overshot the catalogue clearance
- raceway spalling of the CARB bearing after the catalogue L10 life under contaminated lubrication
- fretting corrosion at the shaft-sleeve interface under vibration with an undersized seat
Selection pitfalls — read before you substitute
- Do not re-use a sleeve that shows taper scuffing: a scratched cone changes the travel-to-clearance relationship of the whole C31-1000-KMB-AOH31-1000 unit — replace the sleeve with the bearing.
- Do not run C31-1000-KMB-AOH31-1000 as a locating bearing: the CARB raceway is toroidal and the unit is designed to float axially; blocking it against a shoulder preloads the rollers and ends in thermal failure.
- Contamination discipline: the CARB bearing is open (this execution has no seals); flush the housing before mounting C31-1000-KMB-AOH31-1000 and maintain the lubricant filtration — hard particles indent the toroidal raceway quickly at heavy load.
- The 20400/45500 kN ratings are SKF catalogue 17000 values for the CARB bearing; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification.
- Quote the full unit designation SKF C 31/1000 KMB + AOH 31/1000 when purchasing — bearing and sleeve execution letters are part of the order number and define the matched taper pair.
Frequently asked questions
What are the dimensions and catalogue data of C31-1000-KMB-AOH31-1000?
The unit is CARB bearing C 31/1000 KMB on withdrawal sleeve AOH 31/1000, fitting a 950 mm shaft (37.402 in), housing bore 1580 mm, bearing width 462 mm. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 20400 kN, C0 45500 kN, fatigue load limit Pu 2500 kN, combined mass about 3950.0 kg. Reference speed 220 r/min, limiting speed 300 r/min (bearing values).
Why does C31-1000-KMB-AOH31-1000 list a 950 mm shaft size when the bearing bore is 1000 mm?
The sleeve takes up the difference: the withdrawal sleeve AOH 31/1000 has a tapered outside that engages the bearing's 1000 mm tapered bore and a cylindrical bore that seats on the 950 mm shaft. The catalogue's principal dimensions describe the mounted result — shaft seat, housing bore and bearing width — not the bearing bore alone.
Is C31-1000-KMB-AOH31-1000 a locating or non-locating bearing?
Non-locating. The CARB toroidal roller bearing is designed as the free end of the shaft: its raceway geometry tolerates misalignment and allows axial float, while a separate locating bearing (typically a spherical roller or paired taper) takes the thrust. The sleeve does not change this function.
Can I buy the bearing C 31/1000 KMB and the sleeve AOH 31/1000 separately?
The components are catalogued separately, but the taper pair is matched — the sleeve seat and the bearing bore are manufactured to the same execution. Ordering the unit C31-1000-KMB-AOH31-1000 as one catalogue line keeps bearing and sleeve compatible; if ordering separately, quote both full designations including execution letters.
How is the clearance of C31-1000-KMB-AOH31-1000 set at mounting?
By sleeve travel: the withdrawal sleeve AOH 31/1000 is driven or pressed to a marked travel on the 950 mm seat, which sets the interference into the 1000 mm bore and with it the radial clearance. Record the travel; hydraulic assistance is standard at this size.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.2-10.3 CARB on sleeves on 2026-09-29. Read our editorial & correction policy.