Manufacturing processes


Thread rolling production method

What is thread rolling?

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Thread rolling (often also referred to as thread milling) is the cold forming of the surface of round workpieces. The thread form is produced by causing an enormous force to be exerted between the two rotating rolling dies that form the workpiece. As the roll die profile penetrates the workpiece surface, the material in cold state is pressed all the way down into the root diameter of the thread roll die and is therefore rolled according to nominal value.

Accordingly, a lead accuracy of up to Class G5 as per DIN 69051 (0.023 mm/300 mm) may be reached. This covers the better part of all market requirements.

Advantages of thread rolling:

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  • significant increase in hardness through cold forming
  • excellent surface smoothness values on thread flanks and in ground radius
  • reduced notch sensitivity
  • no interrrupted swalfe as in machine-ground threads
  • accurate thread form run-out tolerances
  • rational and fast manufacture
  • extremely cost-effective especially in large production batches

What materials are ...?

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...suitable

  • all metals that feature an extension of at least 6 % and do not exceed a tensile strength of 1300 N/mm2
  • high-alloy, corrosion and acid-resistant steel
  • special aluminium alloys
  • riveting-quality brass
  • copper alloys
  • threads can be rolled on hollow bodies and tubes only if wall thickness is sufficient; this wall thickness depends upon the type and depth of intended profile. Please call or write for further assistance.

...not suitable

  • extremely brittle material such as Ms58, cast iron, etc.
  • extremely soft materials such as lead
  • synthetics

Our specialties

Thanks to state-of-the-art production methods, extensive product knowledge and more than 1000 tools, we are able to meet each and every demand for rolled threads – however exotic they may be:

  • pitches up to 6 x diameter
  • spindle length up to 6 m
  • spindle diameter from 2 to 160 mm
  • all standard profiles
  • multiple start threads including left/right threads
  • special profiles
  • worm gears (quality and price advantages)
  • serrations and milled edges

Quality assurance system in accordance with SN EN ISO 9001