Methods and apparatus to control hot-start weld current for arc ignition are disclosed. An example welding-type power supply includes a power converter to output welding-type current, a temperature monitor to determine a temperature of an electrode using at least one of a temperature measurement or a thermal model, and a current controller to control a hot-start weld current output by the power converter based on the temperature of the electrode.

My invention is an improvement to a welding arc igniter. My invention periodically disables the arc igniter for one or more AC half-cycles. When the igniter skips an AC half-cycle, the welding arc may not ignite, so average weld heat is reduced. AC weld heat can be adjusted in real time, by varying the fraction of AC half-cycles that are skipped. AC polarity balance can be adjusted in real time, by preferentially skipping the electrode-positive or electrode-negative half-cycles.

Methods and devices for welding arc ignition and, more particularly, to ionizing an area of a contact between an electrode and articles to be welded. Methods and devices for igniting an arc discharge and welding.

A method and a welding device for contactlessly striking an arc between an electrode of a welding head and a material surface of a workpiece. A first ignition voltage pulse with a first or second polarity is generated between the electrode and the material surface. After being struck and, where applicable, after a polarity reversal, the arc is maintained with the second polarity or with an alternating polarity. In the event of an ignition failure, after the first ignition voltage pulse, a sequence of ignition voltage pulses is generated according to a sequence pattern until successful striking of the arc. The sequence pattern includes ignition voltage pulses with the first polarity and ignition voltage pulses with the second polarity, and an ignition pause is provided between ignition voltage pulses with the first polarity and ignition voltage pulses with the second polarity.

A system and method of welding or additive manufacturing is provided where at least two welding electrodes are provided to and passed through a two separate orifices on a single contact tip and a welding waveform is provided to the electrodes through the contact tip to weld simultaneously with both electrodes, where a bridge droplet is formed between the electrodes and then transferred to the puddle.

Methods and apparatus to control hot-start weld current for arc ignition are disclosed. An example welding-type power supply includes a power converter to output welding-type current, a temperature monitor to determine a temperature of an electrode using at least one of a temperature measurement or a thermal model, and a current controller to control a hot-start weld current output by the power converter based on the temperature of the electrode.

My invention is an improvement to a welding arc igniter. My invention periodically disables the arc igniter for one or more AC half-cycles.

When the igniter skips an AC half-cycle, the welding arc may not ignite, so average weld heat is reduced.

AC weld heat can be adjusted in real time, by varying the fraction of AC half-cycles that are skipped.

AC polarity balance can be adjusted in real time, by preferentially skipping the electrode-positive or electrode-negative half-cycles.

A plurality of welding torches, which are disposed in a welding device and are made movable in three-dimensional directions, are provided with welding wires that differ in composition and diameter from each other. When welding is performed in the horizontal direction, an arc is generated by at least two of the welding torches to form a bead while the welding wires are being fed. When welding is performed in the vertical direction, the arc is generated by any one welding torch of the two welding torches to form a bead while the welding wire is being fed. Thus, a steel sheet to which an anti-corrosion material has been applied can be welded continuously with high quality and high-efficiency in a horizontal orientation and vertical orientation.

The present disclosure relates to aluminum production, more particularly, to a method of breaking an electrolyte crust in reduction cells of all types. According to a disclosed method for breaking electrolyte crust by means of separation cutting in a reduction cell for production of aluminum, the crust is cut and broken by means of the thermal melting of a crust material with a high-speed high-temperature concentrated flow of thermal plasma jet heat energy, for which a directed thermal plasma jet is generated and moved above the electrolyte crust along a predetermined path, a formed molten material is continuously removed from a zone of the thermal plasma jet impact to create in the electrolyte crust a slit with the thermal plasma jet, wherein the slit is enough for of crust continuous separation cutting and breaking. The technical effect in the addressing the mentioned object, reduction of the amount of broken electrolyte crust, avoiding the formation of electrolyte crust pieces during the breakage process and, consequently, reduction of power consumption for heating-up the covering material consisting of a mixture of alumina and crushed electrolyte used to form an electrolyte crust.

Systems and methods to start arc welding are disclosed. An example welding-type power supply includes: power conversion circuitry configured to convert input power to welding-type power; and control circuitry configured to: prior to a welding operation, control the power conversion circuitry to stop outputting the welding-type power to a wire electrode; and in response to identifying contact between the wire electrode and a workpiece: control the power conversion circuitry to output an arc starting current to the wire electrode; control a feed motor of a welding torch to retract the wire electrode; control the feed motor to advance the wire electrode based on a first parameter of the welding operation; and control the power conversion circuitry to output the welding-type power to the wire electrode based on the first parameter or a second parameter of the welding operation.