Steel pipe production with HFI welding

Longitudinal welding at SALZGITTER MANNESMANN LINE PIPE is done using the High -Frequency Induction (HFI) process, an electric resistance welding (ERW) technique. In this process, the strip edges are heated to welding temperature and pressed together by rollers without any filler metals to give a homogeneous longitudinal weld.

SALZGITTER MANNESMANN LINE PIPE can draw on decades of experience in the manufacture of welded steel pipe. Rolling stands form the strip into the shape of an open pipe. This is then passed through a ring inductor which induces high-frequency current in the open pipe. The induced current completes its path around the formed strip by flowing along the edges and crowding around the apex of the gap between them. This heats up the open pipe rapidly, raising the strip edges to welding temperature as they arrive at the apex. Pressure rolls force the heated edges together, completing the weld.

What you've always wanted to know about "The manufacture of longitudinally welded steel pipe using the high-frequency induction welding process"

In cooperation with Bergische Universität Wuppertal we have produced a knowledge floater on the subject of HFI-welded steel pipe. In a straightforward, easily understandable style, it serves as an introduction to longitudinal welding using the high-frequency induction process. The focus is on the actual welding process, with a brief digression on weld annealing. As a finishing touch, the floater presents an overview of our products and their applications.

A knowledge floater is a brief educational video that uses numerous auditory and visual elements to provide a concise and interesting outline of a small and self-contained area of knowledge. As a special feature, the instructional texts are also spoken. The resultant audiovisual learning effect turns the presentation into a true multi-sensory learning experience. The floaters can be downloaded free of charge by anyone interested. Pupils and students thus gain an insight into engineering know-how, the manufacture of technical products and their impact on everyday life as well as into the underlying scientific theory. For teachers at schools and universities, podcast science floaters are a useful and stimulating instructional tool.

The HFI knowledge floater is available at:

German version:

English version:

Steel pipe production with HFI welding
Steel pipe production with HFI welding