M.I.G. (Metal Inert Gas) machine follows the process of using the heat generated by a D.C. electric arc to fuse the metal in the joint area of a workpiece. ESAB auto k 400 Thyristorised Power Source for MIG/MAG Welding machine is a type of M.I.G. welding machine. Esab welding machine is well known for its precise and quality welding process. This quality is maintained with the help of a ripple-free D.C. output. It comes along with the remote control to change the welding current and voltage even during the welding process. This type of machine is suitable for mild steel, low carbon steel, alloy steel, etc. The auto k 400 welding machine assures clean and slag free welding. It can withstand the operating current up to 400 amperes and output current ranging from 400 to 500 amperes. It uses thyristor-based technology with a frequency of 50 Hz. Some of its salient features consist of stick out control facility, F.T.T. and F.A.S. systems and self hold circulatory with crater control module within the system. It has a pre-flow of the shield gas with burn back control for optimum utilization. Also, the device has a stable welding condition with protection against single phasing and thermal overload.