Optimization of TIG Repair Welding in Dissimilar Material Sheet, Carbon SteelA516 Grade 60 and Stainless Steel 316L by Taguchi and Statistical Method

The TIG welding is a commercial technique in joining of dissimilar metals in oil and gas industry. The quality ofwelded jointsdependsonproper selection ofweldingparameters. Dissimilar repair welding between sheets of austenitic stainless steel and carbon steel were considered in this article. The purpose of research is selection of optimal welding parameters in order to achieve maximum mechanical strength in the joint. Electrical current, welding speed, gas flow and filler diameter have been selected as considered parameters. In experimental study design of experiments has been performed by Taguchi method. After the preparation and welding of specimens, the tensile testis carried out. Obtained data export to statistical data analysis and optimal welding condition were estimated. To validate obtained data the analysis of variance were employed. According the results welding by 110 amperes, 2.5 electrode diameters, 12.5 l/m flow rate and 190mm/min welding speed reaches to maximum tensile strength in weld metal. By selecting appropriate values of process parameters, tensile strength increased about 15 percent.