Geometry optimization and efficiency increase of HFI welding processes while using SMC-impeders

During HFI welding, an AC inductor generates an electromagnetic field, which induces eddy currents in the pipe workpiece. These eddy currents lead to a resistive heating of the pipes. Magnetic field concentrators, which are conventionally made of ferrite, are used to concentrate the magnetic field and localize the heating in the strip edges of the tube and thus minimize the power loss as far as possible. Optimizing these impeders is one way of increasing the efficiency of the tube longitudinal seam welding process. By using SMC materials in optimized impeder systems for the inductive longitudinal seam welding of tubes, energy savings of around 43 % were achieved for the specific setup. Furthermore, a service life of tS,SMC > 20 h was achieved, which is at least as long as in a conventional system. The geometric machinability of the SMC materials also enables the impeder to be adapted to more complex profile geometries.