Locking Assembly

Working Principle

The main function of a locking assembly is the safe connection of a shaft to a hub by means of friction. For example, between a shaft and a gear hub. The locking assembly creates a play-free connection by expanding between the shaft and the hub.

This type of connection is used mainly for transmitting torque. It is installed by inserting the locking assembly between the components and the subsequent tightening of the screws. By using conical surfaces, the outer diameter increases and the inner diameter reduces. Radial pressure is built up. The clamping forces are provided and controlled by the screws (force-controlled). This allows the direct compensation of the clearance between shaft and hub.

Features & Applications

  • High Durability against Reversing or Impacting Loads - Locking Assembly connection is not affected by torsional load reversal or impact, which damages the key and keyway connection. Locking Assembly fits tightly around the shaft/hub and is free of backlash.
  • Easy and Precise Positioning - Locking Assembly offers 360-degree angular adjustment and is excellent for indexing tables, cam mechanisms, gear drives and double-strand conveyor sprockets.
  • Thrust Capability - Locking Assembly can hold axial forces, too. Typical applications with these forces include indexing tables and bevel gears.
  • Easy Assembly and Disassembly - Locking Assembly can be assembled and disassembled frequently, so maintenance or replacement of worn parts is simple and easy as compared to other methods (key and keyway, spline, shrink or press fits and welding).
  • Increased Shaft Strength - By using Locking Assembly, no metal needs to be removed from the shaft (such as the cutting of a keyway). The strength of the shaft can be kept at its original diameter. This savings can be especially noted on hollow-shaft applications.
  • Eliminates Costly Machining - There is no need for time-consuming machining of keyways. Locking Assembly offers substantial savings on long, heavy shafts.


  • Backlash free connections
  • Ideal for reversing operation
  • Simultaneous transmission of torque and axial force
  • Easy alignment of hub to shaft
  • Compact solutions due to high power density
  • Reduced costs due to simple shaft and hub geometry
  • Connections can be released even after long operation time