C39-630-KM bearing: complete specifications & equivalents

Specification table

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.

Cross references & equivalents

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 C39-630-KM model number is decoded

For long shafts that grow thermally, SKF supplies C 39/630 KM: the toroidal rollers allow the 630 mm inner ring to displace axially without induced thrust, while still accommodating shaft deflection like a spherical bearing. In C 39/630 KM the 39 dimension series fixes the 850 mm OD and 165 mm width around the 630 mm bore (the bore is written directly after the slash (no bore code)); the suffix KM then selects the tapered 1:12 bore for adapter (H) sleeve mounting, machined brass M cage. The K suffix gives a 1:12 tapered 630 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 630×850×165 mm are identical — only the mounting method changes. Pairing rule: use the CARB bearing opposite one locating spherical or tapered bearing — never at both shaft ends — and check the locating bearing takes 100 % of the thrust, since C 39/630 KM deliberately carries none. Seat tolerances follow the ISO 15 recommendation for the heavy-loaded position — the 850 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

Selection pitfalls — read before you substitute

• At 630 mm bore the 275 kg mass and 165 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 39/630 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.
• Tapered-bore K executions mount on adapter sleeves (1:12) and K30 on withdrawal sleeves (1:30) — the 630 mm bore changes the sleeve family, and the drive-up procedure differs accordingly.
• Reference and limiting speeds are different limits: the 530 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 4650/10000 kN ratings belong to this exact execution (C 39/630 KM); VE240 vibrating-screen variants and sealed 2CS/2NS variants have their own figures even at the same envelope.
• The 4650/10000 kN ratings and 275000 g mass are SKF catalogue values transcribed from ch. 10.1 of PUB BU/P1 17000 (PDF table page 866); mounting data — axial displacement (s) and seating details — appears in the running text because the structured record carries the boundary envelope only.