Cold thread Forming – the chipless alternative for high resistant internal threads

HTW - Berlin, Department of mechanical engineering, 12459 Berlin, Germany

^* Corresponding author: roland.heiler@htw-berlin.de

Abstract

In the area of construction and mechanical engineering the designers and production engineers very often do have the task to produce high resistant connections with the possibility of assembling and de assembling parts in a wide range of different materials. Most often connection bolts and internal threads are used to fulfill this task. To produce the internal threads typically the three following internal threading technologies are used: tapping, cold thread forming and thread milling. Tapping and thread milling are metal cutting technologies but cold thread forming is a chipless alternative. Due to the cold forming of the thread this process does have several benefits in comparison to the traditional cutting technologies, but also some special features and process characteristics have to be considered, that it is possible to produce reliable internal threads. In the article the technology is presented with information about the process characteristics, the modern tools design and typical application areas. Results of pull out tests are showing the possibility for producing high resistant threads.