Paper Title
Design & Fabrication of Special Purpose Machine (SPM) for TIG Welding of Pipe to Flange Component

Abstract
Currently welding is the most important and widely used method for metal joining. Among all the available welding methods, TIG welding is the most precise and clean welding process but it requires skilled welder to achieve the precision. Hence the development of a SPM was needed. In this paper, the design and manufacturing of the special purpose machine for welding pipe and flange made up of mild steel and also for welding floats made up of stainless steel using TIG welding set-up. TIG welding machine is the only option as it requires the welding of stainless-steel material. The SPM uses standard TIG welding machine of SigmaWeld having model no SW 400 PT with water cooling setup for automation torch. Further, the machine assembly compromises of in all 7 sub-assemblies, electrical components and pneumatics components. The component is loaded on the fixture assembly along with the provided fixtures. After loading the fixture assembly is tilted to an angle of 45° for welding to begin with the help of jacking assembly. The gantry assembly takes care of the X, Y & Z movement of the welding torch. The AVC (arc voltage control) technology is used to get the automated TIG welding. PLC is used to control all machine operation & AVC. With the use of this SPM all the problems faced during manual TIG welding were overcome. Best weld quality is obtained only in one pass. Keywords - TIG Welding Process, SPM, Automated Voltage Control, Arc Voltage Control, Pipe Welding, Round Jobs Welding