Arc Controllers for TIG Welding Applications:A Review

An arc welding joint could utilize the features of discretely different arc welding methods to obtain the desired joint characteristics. The continuous improvement in arc welding controllers has helped redefine the need of proper parametric control of the process. For efficiency and productivity improvement, modern arc controllers come handy to re-define various aspects of the process (e.g. metal transfer, arc stiffness, etc.). One fascinating outcome is the virtual convergence of complete multi-functional arc welding process to GMAW. Still, there are applications where SMAW and TIG welding processes are regularly being used. Like other welding methods, TIG welding, as well, consists of several derivative approaches. For example, for creating joints of reactive metals (aluminum or magnesium), the AC-TIG welding is commonly employed. Here, the role of arc controller is to generate consistent pattern of desirable rectangular shape AC current waveform through the arc gap. It could cause severe stress (during polarity transition) in all secondary side components of the controller. This review, using indigenously designed peripheral interface controller (PIC) based arc welding inverter, explains the role of arc controllers to handle issues of majority of TIG welding applications.