Self Reversing Tapping Attachment GNCN-GNCK

High performance tapping attachments with integrated reversing gear



Application: tapping, roll forming
Machine type: machining centres and special purpose machines


  • self reversing gear
  • direct collet location
  • damping elements between drive key in the spindle and the coupling sleeve
  • balls used in the couplings elements
  • hydrostatic pressure compensation for IC version
  • constant tapping speed (through built- in reversing gear)
  • exchangeable drivers BN17…
  • built-in length adjustment screw
  • sealed, stable version of the stop arm


  • reversing of machine spindle not required - shortest processing time possible, minimum time saving 200 – 400 ms per thread, substantially less electrical power consumption
  • high concentricity - better life time of the tool, reduced wear, less unbalanced mass
  • avoiding premature wear - less maintenance intensive
  • exact disengaging point -  exact thread depth, high repeat accuracy
  • no axial movement of the spindle into tension, even when the coolant flow is blocked - no risk of collision through extended tool
  • ideal cutting conditions - longer tool life time
  • positive torque transmission of the tap and of the driver in the spindle - no twisting or slipping of the tap in the collet
  • taps can be set to the required length - no input data error of tool length in machine offset (no risk of collision)
  • no malfunction due to contamination or through too much gap in the stop arm - reduced down time of the machine, prevention of collision / no damage from displaced stop arm


Description / Qualities

High performance tapping attachments with integrated reversing gear BILZ tapping attachments are of modular design and can therefore meet the specific requirements of individual machines. They can be used on machining centres with automatic tool changers and on special purpose machines. Because of the integrated maintenance free reversing gear, changes in direction of the machine spindle are unnecessary.

The length compensation on extension, with a ball release system which operates when in reverse, guarantees thread depths of ± 0,15 mm up to a speed of 4000 rpm. The GNCK tapping unit with coolant feed, can facilitate pressures up to a maximum of 50 bar. Precision collets ensure that the tap is securely clamped, and additional square drivers can be utilised where high torque is being generated, for example, when thread forming.

The torque support locks the unit relative to the spindle, thus making automatic tool changing possible. When tool changing takes place, the locking mechanism releases the torque support and allows the tool changing operation to be effected.Because of the use of the reversing gears, high tapping speeds are possible resulting in significantly shorter cycle times compared to conventional tapping.

Extended spindles on request.