Influence of Welding Machine Mechanical Characteristics on the Resistance Spot Welding Process and Weld Quality How machine stiffness, friction, and moving mass can affect welding results

116 ABSTRACT. Mechanical characteristics of resistance spot welding machines, such as stiffness, friction, and moving mass, have complex influences on the resistance welding process and weld quality. In this paper, these influences are systematically investigated through experiments. The mechanisms of the influences are ex- plored by analyzing process signatures, such as welding force and electrode dis- placement, and other process characteris- tics, such as electrode alignment. A better understanding of the influences is achieved through this analysis. This study shows machine stiffness and friction affect welding processes and weld quality. It also confirms the moving mass does not signif- icantly affect the process and quality of re- sistance spot welding.