Analysis of Process Parameters for Projection Welding Process using Single-objective Taguchi Method

Thousands of automobile products need sheet metal components in tremendous quantity world over. High volume of production at lowest possible cost is the driving potential of sheet metal technology which is undergoing technological transformations due to flourishing of automobile industry globally. Projection Welding (PW) is widely utilized for joining purpose especially in automobile industry and fabrication of sheet metal due to its robustness, speed, flexibility and low cost operation. In any car, there are 3000-6000 projection welds which show the level importance of the projection welding. It is a complicated process, which involves interactions of thermal, mechanical, electrical and metallurgical phenomenon. Controlling the welding parameters plays an important role on the quality of the weld. There are various process parameters (weld current, weld time, electrode force) which affect the weld torsional strength and its heat affected zone (HAZ). So it is necessary to optimize the process parameters of projection welding process. The experimental study was conducted for plate thickness 1mm and SQ nut under different electrode force, welding current and weld time. The optimum welding parameters were investigated using the Taguchi method with L9 orthogonal array. In this paper, various optimization techniques are discussed and the uses of the Taguchi method to determine the optimum process parameters are reported. This is because the Taguchi method is a systematic application of design and analysis of experiments for the Purpose of designing and improving product quality at the design stage. Welding parameters settings were determined by using the Taguchi experimental design method. The level of importance of the welding parameters on the torsional strength is determined by using analysis of variance (ANOVA).