This paper invest igates the dynamic behavior of Gas Metal Arc Welding (GMAW) process for two types of power supplies–inverter and rect ifier-for short circuit t ransfer mode. The large ripples on the rect ifier power source are able to perturb the metal t ransfer mode. In this experimental work some operating points in the short circuit mode have been selected using an automatic pipeline welding system, and the effects of both rect ifier and inverter effects (as the power supplies) on the process have been illust rated. For small voltage and currents, the two power supplies effects are similar in the short circuit t ransfer mode. On the other hand, for larger voltage and current values, the responses will be different as the rect ifier power supply produces more perturbations on the metal t ransfer. However, the process with the inverter has a more regular behavior and a more stable detachment .

Keywords