C40-710-K30M bearing: complete specifications & equivalents
The C40-710-K30M is a ISO 15 radial bearing sized 710 x 1030 x 315 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 | 1030 mm |
| Width B | 315 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 10600 kN |
| Basic static load rating C0 | 21600 kN |
| Fatigue load limit Pu | 1320 kN |
| Reference speed (thermal) | 320 rpm |
| Limiting speed (mechanical) | 430 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 865000 g |
| Manufacturer designation | C 40/710 K30M |
| 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 & C4000-series range
| Bore d | 27.953 in |
|---|---|
| Outer diameter D | 40.551 in |
| Width B | 12.402 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 160 mm |
| Smallest bore in C4000-series | 50 mm |
| Largest outer diameter in C4000-series | 1030 mm |
| Width range across C4000-series | 30–315 mm |
| Bore position in C4000-series (smallest first) | 16 of 16 |
| Bore above smallest C4000-series size | 660 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| C40-710-M | SKF | full Dimensions and internal design equivalent — standard interchange. | Same 710×1030×315 mm ISO 15 envelope and equivalent catalogue C/C0; C 40/710 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 C40-710-K30M model number is decoded
C 40/710 K30M belongs to the CARB family — compact aligning roller bearings: envelope 710×1030×315 mm, radial rating 10600/21600 kN C/C0, and no axial-locating function by design. In C 40/710 K30M the 40 dimension series fixes the 1030 mm OD and 315 mm width around the 710 mm bore (the bore is written directly after the slash (no bore code)); the suffix K30M then selects the tapered 1:30 bore for withdrawal (AH) sleeve mounting, machined brass M cage. 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 10600 kN against C0 21600 kN gives a C0/C ratio of 2.04, and the 1320 kN fatigue load limit Pu sets the contamination-adjusted life floor. Mounting: mount on the withdrawal (AH) sleeve matched to the 1:30 tapered bore, drive up to the catalogue reduction and lock the nut; never press through the 315 mm roller set, and leave the free-end housing shoulder clear so axial float is unrestricted.
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
- edge loading and premature spalling when the CARB position is blocked from its designed axial float
- PA66 cage (TN9) softening when the sustained temperature passes the polymer limit
- rolling-contact fatigue spalling after the catalogue L10 life is exhausted
- 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 865 kg mass and 315 mm width make seating geometry dominant: sphered-washer seats and oil flow must be verified in place, not just on the drawing.
- 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.
- Envelope-identical spherical roller bearings (same ISO 15 d×D×B) are not drop-in equivalents — they locate the shaft axially, while C 40/710 K30M must float; the two are designed to be used as a pair.
- The quoted 10600/21600 kN ratings belong to this exact execution (C 40/710 K30M); VE240 vibrating-screen variants and sealed 2CS/2NS variants have their own figures even at the same envelope.
- Never use C 40/710 K30M 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.
- The 10600/21600 kN ratings and 865000 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 C 40/710 K30M mounted?
The tapered 1:30 bore mounts on a withdrawal (AH) 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 40/710 K30M?
A C 40/710 K30M measures 710 mm bore × 1030 mm outside diameter × 315 mm width (27.953 × 40.551 × 12.402 in). From SKF catalogue PUB BU/P1 17000: dynamic C 10600 kN, static C0 21600 kN, fatigue limit Pu 1320 kN, reference speed 320 r/min, limiting speed 430 r/min, mass about 865000 g.
Can a CARB bearing like C 40/710 K30M locate the shaft axially?
No — that is the defining feature. C 40/710 K30M deliberately allows the inner ring to float axially inside the outer ring while the toroidal rollers self-align. It must be paired with a separate locating bearing (spherical, tapered or angular contact) that takes 100 % of the thrust.
How is the C 40/710 K30M designation read?
C = CARB toroidal family; 40 = dimension series; 710 mm (slash-size) = 710 mm bore (the bore is written directly after the slash (no bore code)); suffix K30M selects tapered 1:30 bore for withdrawal (AH) sleeve mounting, machined brass M cage. K is a 1:12 tapered bore for an adapter sleeve, K30 a 1:30 bore for a withdrawal sleeve.
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.