Disclosed is an apparatus for arc welding, comprising: a torch body comprising a power supply line and a gas supply line; two or more metal segments movable relative to one another being sized and shaped to surround a seam between two elongated objects to be welded together, the two or more metal segments being in electrical communication with the power supply line; and a gas jacket attached to each of the metal segments.

The present invention is an apparatus and method for replacing used electrode tips of a TIG welder. The apparatus has a main housing structure with a socket adapter assembly that is operatively supported by the main housing structure. The socket adapter assembly is used to both remove and re-attach the gas shield and the electrode nut of the TIG welder. A vacuum tip suction device that is operatively supported by the main housing structure is used to both remove and install electrode tips for the TIG welder.

A welding system of cylindrical structures which welds a welding end surface of an upper cylindrical structure and that of a lower one in an axial direction thereof, includes: two or more welding apparatuses opposite to the welding end surfaces and disposed at equal arrangement intervals in the circumferential direction thereof; a moving device configured to rotate the upper and lower cylindrical structures relative to the welding apparatuses in a circumferential direction thereof; and a control device configured to control the welding apparatuses and the moving device. The welding apparatus has a filler metal and a heating source therefor, and melts and fuses the filler metal on the welding end surfaces to weld them, and the control device is configured to continuously rotate the upper and lower cylindrical structures an angle of the arrangement interval by the moving device, while welding the welding end surfaces with the welding apparatuses.

A gas tungsten arc welding torch includes a handle and a nozzle located distal of the handle and having a central bore. First and second tungsten electrodes are located partially within the central bore of the nozzle. The torch includes at least one filler wire channel that terminates radially inward of the first tungsten electrode and the second tungsten electrode. The torch includes a torch trigger. Operation of the torch trigger controls delivery of a first filler wire and a second filler wire through the at least one filler wire channel. The torch includes a wire feed speed control. Operation of the wire feed speed control adjusts a wire feed speed of both of the first filler wire and the second filler wire.

In order to provide an improved method for producing metal structures which allows a high level of flexibility in respect of process speed of production, material composition of the metal structure, production accuracy, and the quality of the produced metal structure, according to the invention, a second metal additive is supplied to a welding point on a metal base material, which second metal additive is fused at least by a second electric arc produced between a second electrode and the metal base material in order to produce a second weld seam at the welding point, wherein different materials are used as the first metal additive and as the second metal additive, and wherein the first metal additive and the second metal additive are supplied to the welding point sequentially in time and are fused in the region of the welding point in whichever of the first and second electric arcs is burning, in order to form the three-dimensional metal structure.

In order to synchronize the at least two pulse welding processes performed simultaneously by welding devices in a multiple pulse welding process, the welding devices are connected to one another by a communication link and synchronization information is transmitted via the communication link from a transmitting welding device to at least one receiving welding device. The synchronization information is used in the receiving welding device to synchronize the pulse welding process performed by the receiving welding device with the pulse welding process performed by the transmitting welding device.

A method for synchronizing welding currents of at least two welding current sources prior to performing a simultaneous welding process on at least one workpiece, in particular a welding process with non-consumable electrodes, wherein the method includes the following steps: a first welding current source outputting a reference signal, wherein the reference signal contains synchronization information; a second welding current source measuring or receiving the reference signal and evaluating the synchronization information contained in the reference signal; synchronizing a second welding current of the second welding current source with a first welding current of the first welding current source on the basis of the synchronization information. The invention furthermore relates to a welding current source and to a system having at least two welding current sources.

A welding system configured to eliminate effects of arc blow in a welding operation. The welding system comprises welding circuitry, preheat circuitry, a drive roller, and control circuitry configured to perform a reciprocation cycle. The reciprocation cycle may include the steps of: advancing a filler material toward the welding work piece until the filler material is electrically connected to the weld pool; supplying the preheat power to heat the filler material while the filler material is electrically connected to the weld pool; retracting the filler material away from the welding work piece until the filler material is not electrically connected to the weld pool; and terminating supply of the preheat power to the filler material while the filler material is not electrically connected to the weld pool.

An apparatus and system for preheating and removing surface oxidation of welding wire using electric arcs one via three or more tungsten electrodes connected to a polyphaser preheating power source is disclosed. Electric arc preheating of welding wire allows increased efficiency and deposition rates.

An apparatus and system for preheating and removing surface oxidation of welding wire using electric arcs one via one or more tungsten electrodes is disclosed. The preheating and cleaning electric arcs may occur between tungsten electrodes, or between one or more tungsten electrodes and welding wire. Electric arc preheating of welding wire allows increased efficiency and deposition rates.