The invention relates to an electric arc-welding welding head comprising a contact device and one or more wire feeder units, the contact device encompassing an electrode assembly, the electrode assembly comprising at least two fusible continuously-fed wire electrodes arranged in a contact device. An electrically insulated duct is provided for electric insulation of at least one of the electrodes so that the electrode is electrically insulated from other electrodes in the electrode assembly. The invention also relates to an electric arc-welding contact device and an electric arc-welding welding head assembly.

The invention relates to an electric arc-welding welding head comprising a contact device and one or more wire feeder units, the contact device encompassing an electrode assembly, the electrode assembly comprising at least two fusible continuously-fed wire electrodes arranged in a contact device. An electrically insulated duct is provided for electric insulation of at least one of the electrodes so that the electrode is electrically insulated from other electrodes in the electrode assembly. The invention also relates to an electric arc-welding contact device and an electric arc-welding welding head assembly.

The invention relates to an electric arc-welding welding head comprising a contact device and one or more wire feeder units, the contact device encompassing an electrode assembly, the electrode assembly comprising at least two fusible continuously-fed wire electrodes arranged in a contact device. An electrically insulated duct is provided for electric insulation of at least one of the electrodes so that the electrode is electrically insulated from other electrodes in the electrode assembly. The invention also relates to an electric arc-welding contact device and an electric arc-welding welding head assembly.

Submerged arc welding torch adapted to perform welding in one single pass for each layer on high walls, of the type constituted by a support body from which two wire-guiding lances, held in reciprocal engagement by screws and pins, depart, each of said lances provided with an internal cavity for the insertion of the welding wire, at the end of which a welding material delivery nozzle is provided, characterized by the fact that further departing from said support body are a feeler lance support and a centrally arranged flow delivery duct, said wire-guiding cavities being incorporated into a pair of lances.

An electric arc welder for depositing weld metal along a groove between two edges of a metal workpiece. The welder comprises: a leading electrode driven toward a point in the groove by a first wire feeder operated at a first speed by a first motor with a speed control input and a tachometer derived first feedback signal, a trailing electrode driven toward the same point by a second wire feeder operated at a second speed by a second motor with a speed control input and a tachometer derived second feedback signal, a first power source directing a first current to flow through the leading electrode and a second power source causing a second current to flow through the trailing electrode with the current flow being in a series arc circuit. The second power source being grounded to the workpiece to modify the series arc current so ground current flows to the workpiece whereby the second current is generally equal to the first current minus the ground current.

A system and method of welding is provided where a first welding power supply provides a first welding waveform to a strip electrode for welding a work piece and a second welding power supply provides a second welding waveform to at least one curtain electrode for welding the work piece. The at least one curtain electrode is positioned adjacent to a side of said strip electrode during welding.

A system and method for dual-twin SAW cladding is disclosed. The method includes arranging a first twin SAW head in close proximity to a second twin SAW head, delivering electroslag flux to a surface of a workpiece to create a layer of electroslag flux atop the workpiece, directing two first consumable wires through the first twin SAW head towards the surface of the workpiece, directing two second consumable wires through the second twin SAW head towards the surface of the workpiece, introducing the two first consumable wires and the two second consumable wires into a molten slag pool formed on the surface of the workpiece to melt the two first consumable wires and the two second consumable wires via resistive heating, and translating the first twin SAW head and the second twin SAW head together to form a cladded deposit on the workpiece.

A high-heat-input combined welding method for thick-walled high-strength steel includes following steps. First, a steel plate to be welded is machined into an asymmetric double-sided V-groove, with a depth of a front groove ranging from 30 mm to 40 mm. Then, electrogas welding is used to fill and weld the front groove, with a single-pass heat input controlled below 300 KJ/cm. Finally, a back groove is filled and welded, ensuring that the single-pass heat input for the back groove does not exceed that of the front groove. By adopting an asymmetric double-sided V-groove, the steel plate to be welded is divided into front and back sections. The depth of the groove is restricted to limit the heat input during filling welding.

The present disclosure relates to electro-conduction devices and methods for submerged arc welding of straight-seam steel pipes and in particular to a lateral electro-conduction device and method for multi-wire submerged arc inner/outer welding of a straight-seam steel pipe. The present disclosure aims to overcome the problem of poor closing of the electromagnetic field resulting from the existing negative-pole electro-conduction mechanism and the problem of unstable welding process resulting from bending deformation in the steel pipe welding process. The device includes: a floating surface contact electro-conduction device, capable of forming a surface contact with an outer surface of the straight-seam steel pipe; a lateral electro-conduction brush device, including multiple electro-conduction brushes and electrically connected with the floating surface contact electro-conduction device; a lateral electro-conduction metal plate. electrically connected with a negative-pole wire harness of a welding machine and electrically connected with the lateral electro-conduction brush device.

The disclosed technology generally relates to welding technologies and more particularly to electrode assemblies for arc welding, e.g., submerged arc welding. In one aspect, a welding system comprises a welding power source and an electrode assembly operably coupled to the welding power source and an electrode. The welding power source is configured to apply a direct current electrode negative (DCEN) to the electrode using the electrode assembly to establish an arc between the electrode and a workpiece and to apply a direct current electrode positive (DCEP) or alternating current (AC) to the electrode after the arc is established.