Submerged arc welding torches and systems to resistively preheat electrode wire are disclosed. A disclosed example submerged arc welding torch includes: a first contact tip configured to transfer weld current and preheating current to the wire; a second contact tip configured to conduct the preheating current to the wire; an air-cooled first conductive body portion configured to receive the weld current and to conduct the weld current and the preheating current to the first contact tip; an air-cooled second conductive body portion configured to receive the preheating current and to conduct the preheating current to the second contact tip; and an insulator coupled between the first and second conductive body portions.

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.

Systems and methods are disclosed that provides a helical wire for use in welding applications. A torch can be adapted to form the helical wire from a straight wire and to provide the helical wire as a consumable electrode in a welding or cladding application. The helical wire can be, for example, solid, tubular, or seamless tubular. The torch concurrently forms the helical wire and provides welding current for the welding or cladding application.

A welding method for making cladding or buttering on an inner surface of a base material, an inner surface of an opening portion formed in the base material, and the cut surface formed in such a manner that the cut surface is continuous from the inner surface of the base material to the inner surface of the opening portion, wherein the welding method includes a step of forming a protruding portion on the base material in advance, the protruding portion including a temporary welding surface extending toward the center of the opening portion in such a manner that the temporary welding surface is uniformly continuous to the inner surface of the base material and including the cut surface buried therein.

Disclosed are a flux-cored welding strip and a welding flux used in combination for submerged arc welding of a duplex stainless steel, and preparation methods and use thereof. The flux-cored welding strip is composed of a stainless steel shell and a flux core powder, the flux core powder consisting of the following components: in percentages by mass, ferrochrome nitride: 0.70% to 1.0%, a chromium powder: 26% to 27%, a nickel powder: 4.5% to 5.5%, a molybdenum powder: 3.7% to 4.2%, a manganese powder: 2.55% to 2.65%, a copper powder: 1.45% to 1.55%, a ferrosilicon powder: 1.1% to 1.2%, a tungsten powder: 1.0% to 1.15%, a niobium powder: 0.25% to 0.35%, an aluminum powder: 0.35% to 0.55%, a rhenium powder: 0.35% to 0.40%, a lanthanum powder: 0.1% to 0.15%, and a balance being an iron powder.

A system and method for submerged arc welding. The system advances a consumable welding electrode toward a workpiece, and then stops the advancement when the consumable electrode makes contact with the workpiece. The system provides a preheating current level through the consumable welding electrode proximate the workpiece while the consumable welding electrode is in contact with the workpiece during a preheating period of time to preheat the portion of the consumable welding electrode without establishing an arc. The system then retracts the consumable welding electrode from the workpiece and increases the preheating current level to a welding current level over an arc establishment period of time to establish an arc between the consumable welding electrode and the workpiece. The system then begins to form a weld by advancing the consumable welding electrode toward the workpiece again, resulting in melting the consumable welding electrode and depositing molten metal onto the workpiece.

This disclosure relates generally to welding, and more specifically, to submerged arc welding (SAW). In an embodiment, a welding system includes a gas supply system configured to provide a gas flow. The system also includes a wire supply system configured to provide welding wire, and a flux supply system configured to provide flux near a welding arc during submerged arc welding (SAW). The system further includes a welding torch assembly configured to receive the gas flow and the welding wire and to deliver the gas flow and the welding wire near the welding arc during SAW.

This disclosure relates generally to welding, and more specifically, to submerged arc welding (SAW). In an embodiment, a welding system includes a gas supply system configured to provide a fluorine-containing gas flow. The system also includes a wire supply system configured to provide welding wire, and a flux supply system configured to provide flux near a welding arc during submerged arc welding (SAW). The system further includes a welding torch assembly configured to receive the fluorine-containing gas flow and the welding wire and to deliver the fluorine-containing gas flow and the welding wire near the welding arc during the SAW.

This disclosure relates generally to welding, and more specifically, to submerged arc welding (SAW). In an embodiment, a welding system includes a gas supply system configured to provide a gas flow. The system also includes a wire supply system configured to provide welding wire, and a flux supply system configured to provide flux near a welding arc during submerged arc welding (SAW). The system further includes a welding torch assembly configured to receive the gas flow and the welding wire and to deliver the gas flow and the welding wire near the welding arc during SAW.

This disclosure relates generally to welding, and more specifically, to submerged arc welding (SAW). In an embodiment, a welding system includes a gas supply system configured to provide a fluorine-containing gas flow. The system also includes a wire supply system configured to provide welding wire, and a flux supply system configured to provide flux near a welding arc during submerged arc welding (SAW). The system further includes a welding torch assembly configured to receive the fluorine-containing gas flow and the welding wire and to deliver the fluorine-containing gas flow and the welding wire near the welding arc during the SAW.