The invention relates generally to welding and, more specifically, to welding wires for arc welding, such as Gas Metal Arc Welding (GMAW) or Flux Core Arc Welding (FCAW). In one embodiment, a tubular welding wire includes a sheath and a core. The tubular welding wire is configured to form a weld deposit on a structural steel workpiece, wherein the weld deposit includes less than approximately 2.5% manganese by weight.

Some examples of the present disclosure relate to a cover cap for a welding torch. The cover cap is attached to a housing of the welding torch and rotatable between a closed position, where the cover cap covers an access port of the welding torch, and an open position, where the cover cap does not cover the access port. The welding torch may have welding components within the handle that may be accessed through the access port when the cover cap is in the open position. A cap holder may be used to hold the cover cap in the open position.

A non-consumable electrode arc-welding method is provided for causing a welding machine to output or stop a welding current in accordance with at least an ON state and an OFF state of a start signal. In the method, a start signal is switched between an ON state and an OFF state, thereby controlling the on/off operation of the welding machine. Further, an operation mode instruction signal is switched between a normal mode and an interval mode, thereby controlling the operation mode of the welding machine. When the operation mode instruction signal indicates the interval mode and also the start signal is in the ON state, the welding current is outputted in a welding current output period. Then, the output of the welding current is suspended in a welding current interval period successively following the welding current output period.

There are provided a method for manufacturing an electrical steel sheet laminated core having reduced core loss and improved strength, and a laminated core produced by the manufacturing method. The method includes: stacking electrical steel sheets to obtain a lamination; and welding an outer surface of the lamination, wherein during the welding, a welding wire having a resistivity of 6.510.sup.7 m or greater, a relative permeability of less than 1.02, and a melting point lower than that of the electrical steel sheets is used as a welding material.

The disclosed technology generally relates to consumable electrode wires and more particularly to consumable electrode wires having a core-shell structure, where the core comprises chromium. In one aspect, a welding wire comprises a sheath having a steel composition and a core surrounded by the sheath. The core comprises chromium (Cr) at a concentration between about 12 weight % and about 18 weight % on the basis of the total weight of the welding wire, manganese (Mn) at a concentration between about 12 weight % and about 18 weight % on the basis of the total weight of the welding wire, nickel (Ni) at a concentration between zero and about 5 weight % on the basis of the total weight of the welding wire, and carbon (C) at a concentration greater than zero weight %, wherein concentrations of Ni, C and Mn are such that [Ni]+30[C]+0.5[Mn] is less than about 12 weight %, wherein [Ni], [C], and [Mn] represent weight percentages of respective elements on the basis of the total weight of the welding wire. The disclosed technology also relates to welding methods and systems adapted for using the chromium-comprising electrode wires.

A welding torch (100) for arc welding in a shielding gas atmosphere, includes: a contact tip (25) for feeding a welding wire (13); a suction nozzle (23) surrounding the welding wire, and sucking a gas from a space between the suction nozzle (23) and the welding wire; and a shielding gas supply nozzle (21) provided on the outer periphery of the suction nozzle (23), and supplying the shielding gas toward a welded portion from a space between the shielding gas supply nozzle (21) and the suction nozzle (23). The welding torch (100) satisfies 7Ltk17 and 0Lts18, where Lts [mm] is a distance between the tip of the contact tip (25) and the tip of the shielding gas supply nozzle (21), and Ltk [mm] is a distance between the tip of the contact tip (25) and the tip of the suction nozzle (23).

The shielding gas for MAG welding according to an embodiment is a shielding gas for MAG welding to perform narrow gap welding of a high Cr steel containing 8 wt % to 13 wt % of Cr with one layer-one pass by using a solid wire containing 8 wt % to 13 wt % of Cr, and the shielding gas for MAG welding comprises a ternary mixed gas of 5% by volume to 17% by volume of a carbon dioxide gas, 30% by volume to 80% by volume of a helium gas, and a balance of an argon gas.

The invention relates to nuclear power and can be used in manufacturing of fuel elements for nuclear reactors. A method of sealing nuclear reactor fuel elements is proposed comprising welding one end of a casing with a plug, both of high-chromium steel, loading the fuel element with fuel, and welding a second plug to another end of the casing. The casing is of a high-chromium ferrite-martensite steel and the plug is of a high-chromium ferrite steel. Argon arc welding is carried out at a volume ratio of the materials of the casing and the plug contributing to formation of the metal of the weld seam which allows formation of a ferrite phase in said metal, wherein the ratio is: V.sub.1/V.sub.2>18, where V.sub.1 is the volume of ferrite material and V.sub.2 is the volume of ferrite-martensite material. Argon arc welding is carried out at a current of 14-20 A, a speed of 12-15 m/h, an arc voltage of 9-10 W and an argon flow rate of 7-8 1/min. This method provides for the desired quality of the welded joins and simplifies the fuel element manufacturing process.

An instantaneous gas purge apparatus distributes a flow of a gas, such as an inert gas, directly juxtaposed to a welding seam between two adjacent tubes. The device includes a central hub having radially extending stabilizer arms, mounted inside one of the tubes to be welded. A counterweight and a gas dispersion unit are independently rotatable relative to the hub. The welding operation comprises a continuous rotation of the tubes. Using a stationary welding device, the gravitational pull on the counterweight maintains the gas dispersion unit proximate the welding seam.

A method of welding a superalloy component includes the following sequential steps. A welding step for welding a cavity using a filler metal in an inert atmosphere, where the cavity is located in the component. A covering step for covering the filler metal and a portion of the component with a weld filler layer in the inert atmosphere. The weld filler layer has a greater ductility than material comprising the component and/or material comprising the filler metal. A second covering step for covering the weld filler layer with a braze material, and subsequently performing a brazing operation. A heat treating step heat treats the component.