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Precision lock nuts with axial locking screws

KMD lock nuts (fig. 1) were designed specifically for screw compressors but can be used in other applications where high precision, simple assembly and reliable locking are required. Once the four locking screws are tightened, the lock nut will be accurately positioned at right angles to the shaft thread. The locking screws, when tightened to the recommended tightening torque, preload the lock nut and shaft threads and generate sufficient friction to prevent the nut from loosening under normal operating conditions. The locking screws do not carry any part of the supported load in service.

  • KMD lock nuts are available for thread M 20x1 to M 105x2 (sizes 4 to 21)

Features and benefits

  • Maximum axial run-out between locating face and thread: 0.005 mm
  • Adjustable for precise axial positioning
  • Effective locking prevents the nut from loosening under normal operating conditions
  • Simple installation and removal
  • No keyway required
  • Reusable
  • Designed for frequent installation and removal

The locking principle

Precision lock nuts in the KMD series are locked with axial locking screws. The front of the lock nut locates the component on the shaft. The rear is tightened against the unloaded flank of the shaft thread by axial locking screws, creating sufficient friction to prevent the lock nut from loosening under normal operating conditions (fig. 2) (→ Product data).
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