Patented in 1923, the self-locking collar remains Timken’s most popular locking system to facilitate mounting of wide inner-ring bearings. The self-locking collar eliminates the need for locknuts, washers, shoulders, sleeves and adapters.

With various seal and inner width variations for many agriculture and industrial applications, self-locking collars are the easiest housed unit to install.

The locking collar has a counterbored recess made purposely eccentric to the collar bore. When assembled on the shaft, this eccentric recess engages, or mates, with an eccentric cam end of a bearing’s inner ring. The collar is engaged on the inner cam of the bearing. This assembly grips the shaft tightly with a positive binding action that increases with use. No adjustments of any kind are necessary. The collar setscrew provides supplementary locking.

Design Attributes

  • Unit inserts are full width, allowing them to be more tolerant of static misalignment and capable of holding more aggressive seals.
  • Three-piece, fiber-embedded R-seal has outboard and inboard caps which provide longer sealing integrity than average.
    Eccentric locking collar has self-tightening mechanism.


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