AC electric arc welding system and process with two electrodes

摘要

An electric arc welding system and method for creating a first AC welding arc with a first current waveform between a first electrode and a workpiece by a first power supply and a second AC welding arc with a second current waveform between a second electrode and a workpiece by a second power supply as the first and second electrodes are moved in unison along a welding path where the first and second power supply each comprising an high speed switching inverter creating its waveform by a number of current pulses occurring at a frequency of at least 18 kHz with the magnitude of each current pulse controlled by a wave shaper and the polarity of the waveforms controlled by a signal. The first and second AC waveforms each have a positive portion and a negative portion and a cycle period of about 10-20 ms the electric arc welding system further includes timing circuits for determining the push and pull times between the arcs and a waveform adjusting circuit to limit the push and pull times to less than about 5.0 ms. The electric arc welding method includes the steps of determining the push and pull times between the arcs and adjusting said waveforms to limit the push and pull times to less than about 5.0 ms. <IMAGE>