Dormer Tools Thread forming reduces costly machine downtimes
Thread forming as an alternative method to thread cutting, although not new, remains a relatively unexploited resource that can offer significant benefits over traditional methods.
Although there are many ways of creating threads, probably the most commonly accepted is by cutting the workpiece material with a thread cutting tap (internal) or die (external).
Threading with fluteless taps – also known as cold forming or roll tapping – involves the creation of a thread by forming the material rather than cutting it like other taps.
There are several significant advantages of using this method compared with cutting taps. These include speed, as cold forming is faster than ordinary thread cutting, longer tool life, stronger threads (higher stripping strength) compared to threads obtained by cutting, no chips and a lower surface roughness on the thread.
Fundamentally a cutting tap without the flutes, various designs of fluteless taps exist, but all essentially follow the same basic concept: A thread is ground onto a blank with a specific geometry which introduces forming lobes at the same time, or, conversely, the cylindrical thread is relieved at various positions around the circumference to leave the forming lobes. These lobes spaced periodically around the tap carry out the forming process, creating the thread as the tool is advanced into the material.