Patent ID: 8373093
Filing Date: 2013-02-12
Classification: B23K

Abstract:
1. A method of increasing heat input to a weld during an arc welding process by generating a series of electric arc pulses between an advancing welding electrode and a metal workpiece using an electric arc welding system capable of generating an electric welding waveform to produce said electric arc pulses, said method comprising: (a) regulating an output current level of said waveform to a background current level to sustain an electric arc between said electrode and said workpiece, producing a molten metal ball on a distal end of said electrode; (b) decreasing said output current level below said background current level in response to said molten metal ball shorting to said workpiece and extinguishing said electric arc, to allow said molten metal ball to wet into a puddle on the workpiece; (c) automatically increasing said output current level above said background current level to induce said molten metal ball to pinch off from said distal end of said electrode; (d) decreasing said output current level below said background current level as said molten metal ball pinches off from said distal end of said electrode onto said workpiece, re-establishing an electric arc between said electrode and said workpiece; (e) increasing said output current level to a peak current level of said waveform in response to re-establishing said electric arc; (f) decreasing said output current level toward said background current level, producing a next molten metal ball on said distal end of said electrode; (g) pulsing said output current level, between said background current level and an intermediate current level being between said background current level and said peak current level, at a pre-defined pulse rate until a next short is established between said next molten metal ball and said workpiece; and (h) repeating steps (b) through (g) until said arc welding process is completed.