C3188-MB 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 C3188-MB model number is decoded

C 3188 MB is the dimension series 31 CARB toroidal roller bearings member of the CARB range: 440 mm bore, 720 mm OD, 226 mm width, with the asymmetrical-looking toroidal roller set that defines the CARB principle. In C 3188 MB the 31 dimension series fixes the 720 mm OD and 226 mm width around the 440 mm bore (code 88 × 5); the suffix MB then selects the cylindrical bore for direct shaft fitting, machined inner-ring-guided brass cage (MB). 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 440 mm shaft deflects; the 630 r/min reference and 850 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 3188 MB deliberately carries none. Mounting: slide the bearing onto the 440 mm seat or heat it (max 120 °C) and seat it square; never press through the 226 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 (385 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 630 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 6700/11400 kN ratings belong to this exact execution (C 3188 MB); VE240 vibrating-screen variants and sealed 2CS/2NS variants have their own figures even at the same envelope.
• Envelope-identical spherical roller bearings (same ISO 15 d×D×B) are not drop-in equivalents — they locate the shaft axially, while C 3188 MB must float; the two are designed to be used as a pair.
• Never use C 3188 MB 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 6700/11400 kN ratings and 385000 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.