Installation and removal

KMD precision lock nuts have slots around their circumference to accommodate a hook spanner (fig. 1). The designations of the appropriate spanners are listed in the product table. For more information about the appropriate spanner, refer to Bearing fitting tools. KMD precision lock nuts are supplied with a protector between the front and rear part of the lock nut (fig. 2). The axial locking screws are “finger tight” to keep the protector in place. The lock nuts are designed for frequent installation and removal (provided they are not damaged).

Installation
  1. Loosen the locking screws (1) half a turn. Do not remove them.
  2. Remove the protector (2) between the two parts of the lock nut.
  3. Hold the front and rear parts together and screw the lock nut onto the shaft. When the rear part grabs onto the shaft thread, a gap occurs between the two parts of approximately:
    • 0,6 mm for KMD 4 lock nuts
    • 1,0 mm for KMD 5 to KMD 15 lock nuts
    • 1,2 mm for KMD 16 to KMD 21 lock nuts

The remaining steps depend on whether adjustment to an exact position on the shaft is required.

When precise positioning is not required:
  1. Screw the lock nut to its final position on the shaft thread, engaging the spanner in the slots on the front part of the nut.
  2. Tighten the locking screws alternately in a criss-cross pattern until the recommended torque value is obtained (→ product table). Screw sizes are listed in the product table.

When precise positioning is required:

  1. Screw the lock nut to an approximate position on the shaft thread, using a spanner to engage the slots on the front part of the nut.
  2. Tighten the locking screws alternately in a criss-cross pattern to half the recommended torque value (→ product table). Screw sizes are also listed in the product table.
  3. Adjust the nut to its final position on the shaft (placing the spanner in the slots on the front part of the nut).
  4. Tighten the locking screws alternately in a criss-cross pattern to the full recommended torque.

KMD precision lock nuts should not be used to drive a bearing up onto a tapered seat.

    Removal
    Loosen the locking screws and unscrew the nut from the shaft.
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