C39-710-KM bearing: complete specifications & equivalents
The C39-710-KM is a ISO 15 radial bearing sized 710 x 950 x 180 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 | 950 mm |
| Width B | 180 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 6000 kN |
| Basic static load rating C0 | 12500 kN |
| Fatigue load limit Pu | 780 kN |
| Reference speed (thermal) | 450 rpm |
| Limiting speed (mechanical) | 630 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 360000 g |
| Manufacturer designation | C 39/710 KM |
| 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 & C3900-series range
| Bore d | 27.953 in |
|---|---|
| Outer diameter D | 37.402 in |
| Width B | 7.087 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 120 mm |
| Smallest bore in C3900-series | 360 mm |
| Largest outer diameter in C3900-series | 2180 mm |
| Width range across C3900-series | 90–355 mm |
| Bore position in C3900-series (smallest first) | 8 of 15 |
| Bore above smallest C3900-series size | 350 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| C39-710-M | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 710×950×180 mm ISO 15 envelope and equivalent catalogue C/C0; C 39/710 M is the cylindrical-bore M 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 C39-710-KM model number is decoded
For long shafts that grow thermally, SKF supplies C 39/710 KM: the toroidal rollers allow the 710 mm inner ring to displace axially without induced thrust, while still accommodating shaft deflection like a spherical bearing. SKF builds the CARB order number from size plus execution: the bare number C 39/710 is the brass-caged cylindrical-bore bearing, K (or K30) makes the bore tapered for sleeve mounting, and the cage/seal letters follow — here KM. The K suffix gives a 1:12 tapered 710 mm bore, mounted on an adapter (H) sleeve so the bearing can be driven up to the specified clearance. The same size is listed in both bore executions, and the boundary dimensions 710×950×180 mm are identical — only the mounting method changes. Speed planning separates the 450 r/min thermal reference from the 630 r/min mechanical limiting speed. The full-complement V executions carry more load but list no thermal reference speed; the brass-caged executions run faster and cooler at light load. Open executions accept relubrication — route it through the outer-ring groove on sizes that have one and purge stale grease at service intervals. Grease through the annular groove features where provided; on open executions feed lubricant past the long roller set at assembly, since the 180 mm wide cavity does not fill itself.
Typical equipment & failure modes
Common applications
- paper machine drying cylinders and calender rolls with long, thermally expanding shafts
- continuous-caster guide rolls and slab-caster segments under heat growth
- vibrating screen exciters fitted with the VE240 tolerance execution
- long fan and kiln main shafts where the free end must float without thrust load
Known failure patterns
- roller-end and flange smearing after lubricant starvation at the long roller contacts
- thermal preloading when a shaft is located at both ends and growth has nowhere to go
- brass cage pocket wear under marginal lubrication in the large-bore M/MB executions
- hard-particle indentation where oil or grease filtration is inadequate
- grease churning and overheating when a high-speed thrust position is over-packed
Selection pitfalls — read before you substitute
- At 710 mm bore the 360 kg mass and 180 mm width make seating geometry dominant: sphered-washer seats and oil flow must be verified in place, not just on the drawing.
- Envelope-identical spherical roller bearings (same ISO 15 d×D×B) are not drop-in equivalents — they locate the shaft axially, while C 39/710 KM must float; the two are designed to be used as a pair.
- Never use C 39/710 KM 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.
- Do not block the axial displacement in the drawing: housing covers, labyrinth rings and snap rings must leave the catalogue float (s) free, or the bearing silently becomes a poorly located fixed bearing.
- 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.
- The 6000/12500 kN ratings and 360000 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
Which dimensions does the C 39/710 KM have?
A C 39/710 KM measures 710 mm bore × 950 mm outside diameter × 180 mm width (27.953 × 37.402 × 7.087 in). From SKF catalogue PUB BU/P1 17000: dynamic C 6000 kN, static C0 12500 kN, fatigue limit Pu 780 kN, reference speed 450 r/min, limiting speed 630 r/min, mass about 360000 g.
What does C 39/710 KM mean in SKF part numbering?
C marks CARB; 39 the dimension series; the size code gives 710 mm bore; KM is the execution (tapered 1:12 bore for adapter (H) sleeve mounting, machined brass M cage). The envelope follows ISO 15 and matches spherical roller bearing outlines, but the functions differ.
Why is C 39/710 KM used opposite a spherical roller bearing?
The spherical bearing locates the shaft and takes thrust; the CARB bearing at the other end self-aligns but floats, absorbing thermal expansion without inducing axial load. The pair is standard on paper machine drying cylinders and long caster rolls.
Is the C 39/710 KM sealed?
No, it is an open execution relying on the housing seals; relubrication follows the groove/hole features of the size.
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.