Development of a sensor-less methodology for monitoring quality of spot welding in real time
Wan, Li Xue
Date of Issue2000
School of Mechanical and Aerospace Engineering
Resistance spot welding is widely used for joining metal sheet. Although many attempts have been made to perform the quality assurance, none of the methods available today can provide a satisfactory quality monitoring capability for spot welding without significantly sacrificing productivity of this widely used joining process. This report presents a new method to monitor and diagnose a resistance welding process through measuring the variation of the input electrical impedance (Zin) of a welding system. The Zin is obtained by digitally processing the measured input voltage and current of a welding system.
Nanyang Technological University