C39-850-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 C39-850-KM model number is decoded

In SKF catalogue PUB BU/P1 17000, C 39/850 KM denotes a toroidal roller bearing whose 200 mm long rollers crown at both ends: the contact accepts angular misalignment while the ring positions float, which is why CARB bearings are specified at the free shaft end. The designation C 39/850 KM separates into C (CARB), 39 (dimension series), 850 mm (slash-size) (850 mm bore — bore 850 mm is written directly after the slash) and KM (tapered 1:12 bore for adapter (H) sleeve mounting, machined brass M cage); envelope 850×1120×200 mm follows the ISO 15 plan. The open execution relies on the housing seals and lubrication system, fed through groove/hole features on the large sizes. Explorer-class heat treatment and the crowned roller profile keep edge stress down when the 850 mm shaft deflects; the 360 r/min reference and 480 r/min limiting speed are both catalogue values. 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 39/850 KM deliberately carries none. Seat tolerances follow the ISO 15 recommendation for the heavy-loaded position — the 1120 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 850 mm bore the 540 kg mass and 200 mm width make seating geometry dominant: sphered-washer seats and oil flow must be verified in place, not just on the drawing.
• Reference and limiting speeds are different limits: the 360 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 7350/16300 kN ratings belong to this exact execution (C 39/850 KM); VE240 vibrating-screen variants and sealed 2CS/2NS variants have their own figures even at the same envelope.
• Tapered-bore K executions mount on adapter sleeves (1:12) and K30 on withdrawal sleeves (1:30) — the 850 mm bore changes the sleeve family, and the drive-up procedure differs accordingly.
• Never use C 39/850 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.
• The 7350/16300 kN ratings and 540000 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.