Forming taps

Thread Formers for chipless production of internal threads

If you want to create an internal thread without producing chips, thread formers are the right tool. They are sometimes referred to as thread rollers.

Unlike conventional thread cutting, internal threads are produced through cold forming in this process. For this to be possible, the material to be processed must exhibit good cold formability. Only with such materials can you produce chipless internal threads using a thread former.

Why are no chips produced with a thread former?

While thread cutting or thread drilling removes material, the edges present on the thread former (also called pressure pins) push the base material to the side when forming the thread. The significant advantage of this process lies in its high speed and precision. Additionally, there are no disruptive chips produced, which is crucial for many applications. Comparing tool life between taps and thread formers, the latter can demonstrate significantly higher performance. However, this requires tighter tolerances on the drilled hole. Since no material is destroyed, the surface after thread forming is typically much smoother and has a better structure. Many internal threads produced this way also achieve greater strength.

Thread forming is not possible with all materials

Before using a thread former, you should ensure that the material to be processed is suitable for it. Additionally, you should know that, unlike most cutting tools, thread formers cannot be resharpened. Before the tool can be used, a precise core hole must also be pre-drilled. This is also the case with thread cutting. However, there is a very important difference: in thread cutting, the core hole must be smaller, while in thread forming, it must be larger. The calculation of the core hole size is based on a different principle. The easiest way to determine the correct size is to use standard tables.

Finishing tThread formers reduce scrap

In many applications where taps are otherwise used, the scrap rate can be too high. If this is also the case for you and the material has suitable cold-forming properties, you can try using a thread former instead of a tap. Our quality thread formers M, MF, Gund, and HSSE reduce excessive scrap and prevent the generation of chips where they are not desired.