A multi-process welding machine provides an intuitive user interface to enable a user to select among different welding processes, and to select parameters for a given selected welding process. The multi-process welding machine also provides an arrangement by which a switching module, or DC to AC converter, of an AC TIG unit can be controlled to alternatively supply AC or DC welding voltages or current. Further, a configuration of switches can be leveraged to automatically (or manually) control the polarity of welding cables for different processes and to engage or disengage a wire feeder when, e.g., a MIG welding process is selected, or not selected, respectively. Finally, in an embodiment, the ferrite or magnetic materials used for a main output inductor and an high frequency starting inductor of the welding machine can be combined.

A hard banding apparatus for pipes and other drilling tools. The hard banding apparatus has a floating weld box that moves in response to the shape of the item to be welded. The apparatus can include a drive roller assembly and lift mechanisms that lift and move the weld box or housing to a desired height.

In order to develop a welding process in such a way that uniform flaking of a weld seam can be guaranteed even with a higher number of short-circuit cycles, a specific number of short-circuit cycles is specified for the cold welding phase and the cold phase duration of the cold welding phase is determined for a number of short-circuit cycles that exceeds a specified limit cycle number, depending on a determined cold phase time and after the cold welding phase, there is a switch to the hot welding phase.

In order to develop a welding process in such a way that uniform flaking of a weld seam can be guaranteed even with a higher number of short-circuit cycles, a specific number of short-circuit cycles is specified for the cold welding phase and the cold phase duration of the cold welding phase is determined for a number of short-circuit cycles that exceeds a specified limit cycle number, depending on a determined cold phase time and after the cold welding phase, there is a switch to the hot welding phase.

Welding torch system for use in welding or cutting operations during which fume is created. The welding torch system has a welding torch comprising a contact tip holder and a coaxial nozzle comprising an inner shield gas conduit having a shield gas outlet for supplying a shield gas. The inner shield gas conduit surrounds the contact tip holder. An outer shell at least partly surrounds said inner shield gas conduit. The welding torch system further comprises a shield gas generator and supply unit for supplying shield gas through the shield gas outlet and a fume extracting assembly for extracting fume and ambient air. The welding torch system is arranged for—during operation—supplying shield gas through the shield gas outlet at a velocity between about 1.5 m/s and 10 m/s. By operating the fume extracting assembly to generate a flow of between 10 and 100 m.sup.3/h, preferably a flow of about 55 m.sup.3/h a reduction in the area of 90%-95% of hazardous fumes can then be realized. A welding torch for use in such a system has an inner shield gas conduit having an end portion with an inner surface of which the diameter decreases towards the shield gas outlet. In a method for welding the shield gas is supplied through the shield gas outlet at a velocity between about 1.5 m/s and 10 m/s.

Welding torch system for use in welding or cutting operations during which fume is created. The welding torch system has a welding torch comprising a contact tip holder and a coaxial nozzle comprising an inner shield gas conduit having a shield gas outlet for supplying a shield gas. The inner shield gas conduit surrounds the contact tip holder. An outer shell at least partly surrounds said inner shield gas conduit. The welding torch system further comprises a shield gas generator and supply unit for supplying shield gas through the shield gas outlet and a fume extracting assembly for extracting fume and ambient air. The welding torch system is arranged for—during operation—supplying shield gas through the shield gas outlet at a velocity between about 1.5 m/s and 10 m/s. By operating the fume extracting assembly to generate a flow of between 10 and 100 m.sup.3/h, preferably a flow of about 55 m.sup.3/h a reduction in the area of 90%-95% of hazardous fumes can then be realized. A welding torch for use in such a system has an inner shield gas conduit having an end portion with an inner surface of which the diameter decreases towards the shield gas outlet. In a method for welding the shield gas is supplied through the shield gas outlet at a velocity between about 1.5 m/s and 10 m/s.

Provided is an arc welding device that performs welding by alternately repeating a short-circuit period provided with a short-circuit state in which a welding wire and a base material are short-circuited, and an arc period provided with an arc state in which an arc is generated between the welding wire and the base material. A calculation unit calculates an integrated power value by integrating power supplied to the welding wire within a predetermined period, after the welding wire is short-circuited. A controller reduces a welding current to be supplied to welding wire when the integrated power value is larger than a predetermined threshold.

In arc welding in which a welding wire serving as a consumable electrode is fed toward a base material and a welding current is caused to flow through the welding wire and the base material to alternately repeat a reverse polarity period and a positive polarity period, after a short circuit between the welding wire and the base material is detected, a feeding speed of the welding wire is changed from a first feeding speed to a second feeding speed on a negative side of the first feeding speed when a speed in a direction toward the base material is defined as positive.

Arc welding, in which a welding wire serving as a consumable electrode is fed toward a base material and a welding current alternately including a peak current and a base current is caused to flow through the welding wire and the base material, is performed such that after a short-circuit between the welding wire and the base material is detected, a feeding speed of the welding wire is changed from a first feeding speed to a second feeding speed that is on a negative side from the first feeding speed when a speed in a direction in which the welding wire is fed toward the base material is defined as positive.

An example welding power supply includes: power conversion circuitry configured to convert supply power to welding current and to output the welding current to at least one of a shielded metal arc welding (SMAW) electrode or a gouging torch; a voltage sense circuit configured to measure an output voltage of the power conversion circuitry; and control circuitry configured to: control the power conversion circuitry using a current-controlled control loop based on a target current; while the output voltage is above a lower voltage limit, control the target current based on a difference between a reference voltage and the output voltage; and in response to detecting that the output voltage has decreased below the lower voltage limit, control a welding current output by the power conversion circuitry based on a first exponential relationship.