C3068-M 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 C3068-M model number is decoded

The CARB bearing C 3068 M combines the self-aligning behaviour of a spherical roller bearing with the axial freedom of a cylindrical bearing in one 340 mm bore, 520 mm outside diameter, 133 mm wide unit rated 2900 kN dynamic. The designation C 3068 M separates into C (CARB), 30 (dimension series), 68 (340 mm bore) and M (cylindrical bore for direct shaft fitting, machined brass M cage); envelope 340×520×133 mm follows the ISO 15 plan. The M suffix is a one-piece machined brass cage centred on the rollers, supplied for the 340 mm and larger sizes needing robust guidance under heavy load. Speed planning separates the 950 r/min thermal reference from the 1,300 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. Mounting: slide the bearing onto the 340 mm seat or heat it (max 120 °C) and seat it square; never press through the 133 mm roller set, and leave the free-end housing shoulder clear so axial float is unrestricted.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Above 200 mm bore these bearings weigh tens of kilograms (100 kg here) — lifting gear and induction heating are mandatory, and a cocked ring scores the toroidal raceway before start-up.
• Reference and limiting speeds are different limits: the 950 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 2900/5000 kN ratings belong to this exact execution (C 3068 M); VE240 vibrating-screen variants and sealed 2CS/2NS variants have their own figures even at the same envelope.
• 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.
• Never use C 3068 M 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 2900/5000 kN ratings and 100000 g mass are SKF catalogue values transcribed from ch. 10.1 of PUB BU/P1 17000 (PDF table page 864); mounting data — axial displacement (s) and seating details — appears in the running text because the structured record carries the boundary envelope only.