C31-710-KMB bearing: complete specifications & equivalents
The C31-710-KMB is a ISO 15 radial bearing sized 710 x 1150 x 345 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 710 mm |
| Outer diameter D | 1150 mm |
| Width B | 345 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 13400 kN |
| Basic static load rating C0 | 25500 kN |
| Fatigue load limit Pu | 1530 kN |
| Reference speed (thermal) | 340 rpm |
| Limiting speed (mechanical) | 480 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1470000 g |
| Manufacturer designation | C 31/710 KMB |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal roller bearings |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal roller bearings) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal roller 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 & C3100-series range
| Bore d | 27.953 in |
|---|---|
| Outer diameter D | 45.276 in |
| Width B | 13.583 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 220 mm |
| Smallest bore in C3100-series | 100 mm |
| Largest outer diameter in C3100-series | 1580 mm |
| Width range across C3100-series | 52–462 mm |
| Bore position in C3100-series (smallest first) | 26 of 28 |
| Bore above smallest C3100-series size | 610 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| C31-710-MB | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 710×1150×345 mm ISO 15 envelope and equivalent catalogue C/C0; C 31/710 MB is the cylindrical-bore MB inner-ring-guided brass-caged execution of this size — boundary dimensions interchangeable, only mounting and cage execution differ. |
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 C31-710-KMB model number is decoded
C 31/710 KMB is a CARB toroidal roller bearing to ISO 15: a single row of long, symmetrical barrel-shaped rollers between guide flanges, sized 710×1150×345 mm, as listed in SKF catalogue PUB BU/P1 17000 ch. 10.1. In C 31/710 KMB the 31 dimension series fixes the 1150 mm OD and 345 mm width around the 710 mm bore (the bore is written directly after the slash (no bore code)); the suffix KMB then selects the tapered 1:12 bore for adapter (H) sleeve mounting, machined inner-ring-guided brass cage (MB). CARB bearings locate neither radially nor axially: the inner ring can walk axially inside the outer ring over the catalogue-listed axial-displacement range (s), so shaft thermal growth disappears as thrust rather than preloading the 710 mm seat. Selection arithmetic: C 13400 kN against C0 25500 kN gives a C0/C ratio of 1.90, and the 1530 kN fatigue load limit Pu sets the contamination-adjusted life floor. Seat tolerances follow the ISO 15 recommendation for the heavy-loaded position — the 1150 mm outer ring typically takes a loose housing fit to preserve float, and the rings must be supported across their full faces.
Typical equipment & failure modes
Common applications
- heavy industrial gearbox layshafts used as the non-locating position
- winder and reel drums in paper and steel strip plants
- paper machine drying cylinders and calender rolls with long, thermally expanding shafts
- continuous-caster guide rolls and slab-caster segments under heat growth
Known failure patterns
- raceway spalling once the catalogue L10 life is exceeded or after sustained overload
- thermal preloading when a shaft is located at both ends and growth has nowhere to go
- PA66 cage (TN9) softening when the sustained temperature passes the polymer limit
- electrical erosion of raceways on VFD-driven shafts without grounding or insulation
- oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips
Selection pitfalls — read before you substitute
- At 710 mm bore the 1470 kg mass and 345 mm width make seating geometry dominant: sphered-washer seats and oil flow must be verified in place, not just on the drawing.
- Never use C 31/710 KMB as the locating bearing: it carries no axial load by design — the arrangement needs a separate locating spherical, tapered or angular bearing facing the thrust.
- Tapered-bore K executions mount on adapter sleeves (1:12) and K30 on withdrawal sleeves (1:30) — the 710 mm bore changes the sleeve family, and the drive-up procedure differs accordingly.
- Reference and limiting speeds are different limits: the 340 r/min reference speed is the thermal criterion under load, the limiting value is the mechanical ceiling; observe the reference under load unless the arrangement calculation says otherwise.
- The quoted 13400/25500 kN ratings belong to this exact execution (C 31/710 KMB); VE240 vibrating-screen variants and sealed 2CS/2NS variants have their own figures even at the same envelope.
- The 13400/25500 kN ratings and 1470000 g mass are SKF catalogue values transcribed from ch. 10.1 of PUB BU/P1 17000 (PDF table page 868); mounting data — axial displacement (s) and seating details — appears in the running text because the structured record carries the boundary envelope only.
Frequently asked questions
How is the C 31/710 KMB designation read?
C = CARB toroidal family; 31 = dimension series; 710 mm (slash-size) = 710 mm bore (the bore is written directly after the slash (no bore code)); suffix KMB selects tapered 1:12 bore for adapter (H) sleeve mounting, machined inner-ring-guided brass cage (MB). K is a 1:12 tapered bore for an adapter sleeve, K30 a 1:30 bore for a withdrawal sleeve.
What is the difference between V and TN9 CARB executions?
V is the full-complement execution with no cage — more rollers, higher C (13400 kN here) but a lower speed ceiling and no thermal reference speed. TN9 is the glass-fibre PA66 caged execution, faster and quieter at somewhat lower load. C 31/710 KMB is the tapered 1:12 bore for adapter (H) sleeve mounting, machined inner-ring-guided brass cage (MB).
How is C 31/710 KMB mounted?
The tapered 1:12 bore mounts on an adapter (H) sleeve with a defined drive-up; heat the bearing to max 120 °C when fitting, support full ring faces, and verify axial float afterwards.
What are the dimensions and ratings of the C 31/710 KMB?
A C 31/710 KMB measures 710 mm bore × 1150 mm outside diameter × 345 mm width (27.953 × 45.276 × 13.583 in). From SKF catalogue PUB BU/P1 17000: dynamic C 13400 kN, static C0 25500 kN, fatigue limit Pu 1530 kN, reference speed 340 r/min, limiting speed 480 r/min, mass about 1470000 g.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal roller bearings on 2026-09-27. Read our editorial & correction policy.