The high speed rotating arc process forms flat bead surface and decreased penetration depth, so it is suitable for horizontal fillet welding. Foremost it can be applied to the automatic seam tracking in horizontal fillet welding with small leg length, because the amplitude of current waveform increases as the rotation speed increases.
The modeling of the relationship between the contact tip-to-workpiece distance (CTWD) and the welding current, were proposed in self-regulating mode, where the power source has a flat or constant-voltage characteristics. In high speed rotating arc process, it is required that new modeling for the relationship between the CTWD and the welding current, because self-regulation for arc length can not be performed.
In this study, mathematical modeling was proposed to determine the relationship between the CTWD and the welding current in high speed rotating arc. Moreover the arc rotation mechanism was developed to examine the reliability of proposed mathematical modeling and to implement the automatic seam tracking. It was revealed that mathematical modeling for relationship between the CTWD and the welding current was effectively implemented to estimate the amplitude of current waveform.
