Installation and removal

Lock nuts requiring a keyway are easy to install. Each nut is provided with four, equally spaced slots around their circumference to accommodate a hook or impact spanner. The designations of the appropriate spanners are listed in the relevant product table. For more information about the appropriate spanner, refer to Bearing fitting tools.
Lock nuts requiring a keyway can be reused, provided they are not damaged. A new lock washer, locking clip or locking plate should be used each time the corresponding lock nut is reinstalled.
Using lock nuts with lock washer to lock a bearing

Mounting bearings and components on a cylindrical shaft

  1. Put the bearing in place onto the cylindrical shaft.
  2. Go ahead with step 5 below Locking the bearing.

Mounting bearings on an adapter sleeve or tapered seat

  1. Slide the bearing onto the adapter sleeve or tapered seat.
  2. With the chamfer facing the bearing, screw the nut (without the lock washer) onto the adapter sleeve or shaft thread (fig. 1).
  3. Tighten the nut with a hook or impact spanner (fig. 2) until the correct clearance in the bearing is obtained.
  4. Remove the nut. Go to step 5.

Locking the bearing

  1. Slide the lock washer onto the thread until it touches the bearing. With the chamfer facing the bearing, screw the lock nut into place (fig. 3).
  2. Tighten the nut firmly against the lock washer and bearing with a hook or impact spanner, making sure to not over-tighten the nut. For bearings on adapter sleeves or tapered shafts, make sure that the bearing is not driven up any further on its seat.
  3. Lock the nut in place by bending one of the lock washer tabs down into one of the slots on the nut (fig. 4). Do not bend the tab to the bottom of the slot.
Using lock nuts with locking clips to lock a bearing
  1. With the bearing or component in position, screw the lock nut into place.
  2. Tighten the nut against the bearing or component with an impact spanner (fig. 5), aligning one of the slots in its outside diameter with the keyway in the shaft thread and making sure to not over tighten it.
  3. Place the spring washer and locking clip onto the attachment bolt.
  4. Position the locking clip in the keyway in the shaft thread, and the slot in the nut outside diameter, and secure with the attachment bolt and spring washer. Align the bolt with one of the threaded holes on the side face of the lock nut.
  5. Tighten the bolt (fig. 6) with an appropriate wrench.
Using lock nuts with locking plates to lock a bearing
  1. With the bearing or component in position, screw the lock nut into place.
  2. Tighten the nut against the bearing or component with an impact spanner. For mounting bearings on an adapter sleeve or tapered seat, tighten the nut until the correct bearing internal radial clearance is obtained, and making sure to not over tighten it (fig. 7).
  3. Position the locking plate in the keyway.
  4. Tighten the nut further, if required, to align the holes in the plate with the holes on the side face of the nut, making sure that the plate maintains its position in the keyway.
  5. Screw both bolts into the side face of the lock nut and tighten them.
  6. Thread the wire supplied with the locking plate through the holes in the head of both bolts in a figure 8 pattern.
  7. Twist the ends of the wire together to prevent the bolts from loosening (fig. 8).
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