Installation Procedure for HARDLOCK Bearing Nut (HLB)


Install the convex nut manually.


Use a hook wrench or other tightening tool to tighten the convex nut to the torque required for the target application.


Make sure that the gap between the convex nut and concave nut is about one thread pitch. Screw the concave (lock) nut onto the convex nut manually until it no longer turns.>


Tighten the concave nut in the same way as the convex nut. Use a torque wrench to tighten the concave nut to the recommended torque set by Hardlock. If a torque wrench is not available, tighten the nut manually until it no longer turns, then use a regular tightening tool and tighten the nut at least one full turn (360 degrees) to obtain sufficient locking effect.


When the nuts are tightened correctly, a gap may still remain between the nuts due to the shaft diameter tolerance. Regardless of whether or not there is a gap, the Hardlock Bearing Nut will produce a sufficient locking effect if tightened correctly according to these instructions.


If the bearing is fixed, the convex nut and concave nut can be installed in the opposite order (concave first, convex second) with no reduction in the self-locking effect.

More information about HLB:

Dimensions of HARDLOCK Bearing nut?
Torque values for HARDLOCK Bearing Nut?