Abstract: A conventional arc welder control console is integrated with a portable engine-powered weld current generator to eliminate the need for a separate large, high current, 3 phase AC electrical generator when the arc welder is used in the field.

Abstract: A welding head employs a carriage assembly for guiding the welding head along a track or guide. A torch assembly, mounted on the carriage assembly, is configurable for multiple welding processes. The torch assembly includes a torch block and a GTA filler wire guide mounted together on a mounting plate, whereby the GTA filler wire guide is placed in general proximity of a welding torch mounted on the torch block. The torch block accommodates the mounting of either of a GMA torch and a GTA torch. Additionally, the torch block accommodates placement of a GMA adapter sleeve within the torch block to feed a filler wire through the GMA torch. A system control unit provides manual, semi-automated, or automated control of welding system resources including a welding power supply, a supply of one or more shielding gasses, and a fluid coolant supply.

Abstract: A welding process for non-stainless steel workpieces using GTAW equipment and hydrogen containing shield gas on a first root pass is improved by using a shield gas delivery system comprising hoses or conduits made of elastomeric material having a moisture permeability coefficient of less that 275, preferably less than 100, and using a tungsten electrode composition comprising at least tungsten and lanthanum oxide, and preferably tungsten, lanthanum oxide, yttrium oxide and zirconium oxide. Preventing moisture permeation through the elastomeric hoses delivering hydrogen containing shield gas eliminates expulsion of fused weld metal during second pass filler welding over the root pass weld. Electrode life is enhanced using the tungsten compounds.

Abstract: A welding head employs a carriage assembly for guiding the welding head along a track or guide. A torch assembly, mounted on the carriage assembly, is configurable for multiple welding processes. The torch assembly includes a torch block and a GTA filler wire guide mounted together on a mounting plate, whereby the GTA filler wire guide is placed in general proximity of a welding torch mounted on the torch block. The torch block accommodates the mounting of either of a GMA torch and a GTA torch. Additionally, the torch block accommodates placement of a GMA adapter sleeve within the torch block to feed a filler wire through the GMA torch. A system control unit provides manual, semi-automated, or automated control of welding system resources including a welding power supply, a supply of one or more shielding gasses, and a fluid coolant supply.

Abstract: A welding process for non-stainless steel workpieces using GTAW equipment and hydrogen containing shield gas on a first root pass is improved by using a shield gas delivery system comprising hoses or conduits made of elastomeric material having a moisture permeability coefficient of less that 275, preferably less than 100, and using a tungsten electrode composition comprising at least tungsten and lanthanum oxide, and preferably tungsten, lanthanum oxide, yttrium oxide and zirconium oxide. Preventing moisture permeation through the elastomeric hoses delivering hydrogen containing shield gas eliminates expulsion of fused weld metal during second pass filler welding over the root pass weld. Electrode life is enhanced using the tungsten compounds.

Abstract: A system and method for controlling a weld-current in an arc welding apparatus involves programming of a waveform generator to supply a control signal to a weld-current power supply, the control signal being derived from a reference waveform consisting of selected segments having fixed or predetermined amplitudes and variable durations. The reference waveform may be dynamically adjusted in response to changes in welding conditions by feeding the output of an arc current and/or voltage detector back to the waveform generator and varying the duration of selected predetermined amplitude segments.

Abstract: A system and method for controlling a weld-current in an arc welding apparatus involves programming of a waveform generator to supply a control signal to a weld-current power supply, the control signal being derived from a reference waveform consisting of selected segments having fixed or predetermined amplitudes and variable durations. The reference waveform may be dynamically adjusted in response to changes in welding conditions by feeding the output of an arc current and/or voltage detector back to the waveform generator and varying the duration of selected predetermined amplitude segments.

Abstract: A system for aligning and guiding a weld head or torch along a desired weld path includes a travel mechanism for moving a weld head assembly along a fixed path and a steering mechanism for moving a weld head or torch relative to the fixed path in order to follow a desired weld path. A method of establishing the desired weld path includes the steps of establishing coordinates of the path by moving the weld head or torch to positions along the desired path and recording locations of the weld head or torch at the desired positions. Movement of the weld head or torch between the coordinates is achieved by interpolating a path as the weld head or torch is moved from one coordinate to the next following initiation of an automatic steering program.

Abstract: A process for buttwelding metal workpieces having bevelled joint preparations using an automatic GTAW welder using filler wire includes preparing the bevelled workpiece with bevelled joint areas having minimal land thickness at the root extremities; placing the prepared workpiece joint sections together with an open gap between their adjacent root extremities, the gap having a minimum dimension that avoids harmful compression stress between the workpieces due to weld shrinkage and a maximum dimension that avoids filler wire penetration of the gap; fusion welding the open root area of the adjacent workpieces with a root pass weld using an automatic GTAW welder supplied with filler wire and a shield gas including 1 to 10% hydrogen and the balance inert gas; and then promptly overlaying the root pass weld with at least one additional filler weld pass using an automatic GTAW supplied with filler wire and hydrogen-free shield gas.