Signal pattern analysis of high speed rotational arc sensor in GMAW

Signal patterns of high speed rotational arc sensor in gas metal arc welding (GMAW) have been studied. For V-groove butt joint, a geometry model of the weld bead profile and torch rotating has been developed. Welding current waveforms of both simulations and experiments have been analyzed. The welding current waveforms simulated based on the mathematical model are consistent with those captured in welding experiments, which proves that the mathematical model is correct. The signal features are analyzed as arc rotating frequency, radius and torch deviation from V-groove centre varied. The results show that the deviation of the welding torch is in proportion with the asymmetry of the current waveform in corresponding arc rotational cycle. The frequency and radius of arc rotation influence the signal patterns of current waveforms. Arc length and wire extension were also simulated using the mathematical model. The results of this study are helpful to the design and application of high speed rotational arc sensors.