C31-1000-KMB-OH31-1000-HE bearing: complete specifications & equivalents
The C31-1000-KMB-OH31-1000-HE 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 | 4300000 g |
| Manufacturer designation | SKF C 31/1000 KMB + OH 31/1000 HE |
| 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-adapter-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-adapter-sleeve | 25 mm |
| Largest outer diameter in carb-adapter-sleeve | 1580 mm |
| Width range across carb-adapter-sleeve | 20–462 mm |
| Bore position in carb-adapter-sleeve (smallest first) | 50 of 51 |
| Bore above smallest carb-adapter-sleeve size | 925 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-OH31-1000-HE model number is decoded
The OH 31/1000 HE execution mounts the 1000 mm K-bore bearing with a controlled squeeze on the 950 mm shaft: the sleeve cone sets both the interference fit on the shaft and the running clearance inside the CARB bearing, so clearance measurement belongs to the mounting procedure, not to fitting feel. Dividing C 20400 kN by the 1000 mm bore gives 20.40 kN per millimetre of journal — compare this density against neighbouring CARB sizes when the 950 mm seat is fixed and the life requirement is not. The locknut torque of OH 31/1000 HE sets the sleeve travel; use the SKF procedure (measure clearance reduction, not torque feel) — over-driving the sleeve preloads the 1000 mm CARB bearing and overheats the unit within hours. Spare-parts note: order C31-1000-KMB-OH31-1000-HE as the unit; a bare C 31/1000 KMB plus a separately sourced sleeve risks taper mismatch — the catalogue pairing is the guarantee that seat and bore were ground for each other.C31-1000-KMB-OH31-1000-HE is a complete SKF mounting unit: the CARB toroidal roller bearing C 31/1000 KMB supplied on its withdrawal sleeve OH 31/1000 HE, listed in SKF catalogue PUB BU/P1 17000 for a 950 mm shaft seat.Numbering logic: the bearing half C 31/1000 KMB follows the CARB works numbering (type C, dimension series, 1000 mm bore), while OH 31/1000 HE identifies the sleeve execution for that bore; the combo C31-1000-KMB-OH31-1000-HE exists in the catalogue so that shaft (950 mm), housing (1580 mm) and both components are specified with one order number.
Typical equipment & failure modes
Common applications
- vibrating screen exciters fitted with the VE240 tolerance execution
- 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
- paper machine drying cylinders and calender rolls with long, thermally expanding shafts
Known failure patterns
- sleeve creep on the shaft seat when the sleeve was not driven to its marked travel or clearance
- 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
- misalignment edge loading when the housing bore is out of square with the shaft seat
- raceway spalling of the CARB bearing after the catalogue L10 life under contaminated lubrication
Selection pitfalls — read before you substitute
- Protect the 950 mm seat: sleeve bore corrosion or seat ovality shows up later as sleeve creep and fretting; inspect and measure the seat at every dismounting of C31-1000-KMB-OH31-1000-HE.
- Never set C31-1000-KMB-OH31-1000-HE by locknut torque or "feel": the withdrawal sleeve travel defines the clearance of the 1000 mm CARB bearing — measure residual radial clearance during mounting, in steps.
- Sleeve and bearing are a matched taper pair: never fit sleeve OH 31/1000 HE onto a different CARB bearing of the same bore size without verifying the execution letters — seat length and taper contact differ.
- 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 + OH 31/1000 HE 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-OH31-1000-HE?
The unit is CARB bearing C 31/1000 KMB on withdrawal sleeve OH 31/1000 HE, 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 4300.0 kg. Reference speed 220 r/min, limiting speed 300 r/min (bearing values).
Why does C31-1000-KMB-OH31-1000-HE list a 950 mm shaft size when the bearing bore is 1000 mm?
The sleeve takes up the difference: the withdrawal sleeve OH 31/1000 HE 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-OH31-1000-HE 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 OH 31/1000 HE 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-OH31-1000-HE 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-OH31-1000-HE set at mounting?
By driving the adapter sleeve up its conical seat: the sleeve expands on the 950 mm shaft and onto the bearing bore, reducing the radial internal clearance. Mount in steps and measure residual clearance until it reaches the catalogue value for the K bore — never set it by nut torque alone.
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.