Optimal design of electrode cooling system for resistance spot welding with the response surface method

Resistance spot welding (RSW) is typically used in automobile body assembly, where continuous efficiency depends on electrode life, which is closely related with the water cooling effect. In this paper, the finite element simulation and response surface analysis methods are adopted to optimize the RSW electrode cooling process. Aiming to optimal cooling parameters and improve cool effect, we present a special sphere-shape weld cap with inlet pipe and cooling cavity and model its cooling effect as non-linear polynomial equations, which can avoid numerous influential factors. Electrode parameters, including pipe diameter, pipe height and flow velocity, are adjusted according to these non-linear equations. Optimization is carried out subsequently and experimental measurements on electrode diameters are performed for validation. It is found that the response surface model not only indicates the direction of design modification, but also leads to an optimal method for electrode design.