Mario Kusch (Technical University of Chemnitz)
Development of line technology for plasma MIG welding
The principle and advantages of the plasma MIG welding method have been known for around 30 years. Due to the fact that an industrially approved technology is not available, however, the method is practically never used. The increased use of aluminium as a constructional material is currently leading to increased interest in the process by industry.
For this reason, systematic investigations of the conceptional design of plasma MIG welding systems were carried out based on the latest welding technology. Power source technology was evaluated in terms of suitability for plasma MIG welding with regard to type of power and control system. The requirements for ignition mechanisms and properties of the power source modules were also considered. In order to achieve a reproducible process workflow, there must be a technical control link between the individual parts of the system. Modern electronics provide almost unlimited possibilities for this. The greatest research and development requirements were necessary in the area of welding torch design. Here, numerous investigations of electrical insulation, torch cooling, choice of material and flow design of the gas feed were carried out. The prototypes produced during the investigations were used to carry out numerous welding trials, enabling the results achieved during the investigations to be checked for their technological feasibility.