A welding gun assembly having a connection between a diffuser and the inner gun tube which provides increased strength between the diffuser and the gun tube to prevent inadvertent damage to the welding torch and upstream components. The diffuser comprises an engagement portion which engages with, and overlaps, at least a part of a sturdier portion of the inner gun tube. This engagement provides a stronger and more stable connection between the gun tube and the diffuser.

The constricting nozzle of the present invention includes (i) a cylindrical nozzle body disposed around the forward end of the tungsten electrode rod concentrically with the tungsten electrode rod and defines an annular high-speed gas passage between the nozzle body and the outer peripheral surface of the forward end of the tungsten electrode rod, (ii) a plurality of positioning projections that are protrudently formed on the inner peripheral surface of the nozzle body with predetermined intervals in the circumferential direction and that are arranged along the longitudinal direction of the nozzle body to hold the tungsten electrode rod in the center position of the nozzle body, and (iii) a plurality of gas-flow regulating grooves formed between the positioning projections and that extend in parallel in the longitudinal direction of the nozzle body and regulate the shielding gas (G) flowing through the high-speed gas passage.

A weld overlay system includes a workpiece jig holding a workpiece in manner that the workpiece center axis direction is parallel to X-axis direction, and rotates the workpiece in circumferential direction, a carriage, welding base supported on the carriage in manner that the welding base is displaceable with respect to the carriage in Y-axis direction and Z-axis direction, at least one pair of rollers and welding torch are supported on the welding base, and like. Pair of rollers include rotary shafts extend in parallel with the X-axis and are spaced apart from each other in Y-axis direction. The rollers are pressed against portion of the workpiece above the workpiece center axis C. The welding torch is supported on the welding base in manner that distances in Y-axis direction from the rotary shafts of the pair of rollers to the tip end of the welding torch are equal to each other.

At a base metal side end of a torch nozzle, discharge groove 14 in an approximately U-shape is formed. A specific gas received from receiving port 13 is discharged from discharge groove 14 in approximately U-shape. Thus, for example, when a surface diameter of a molten pool reaches a predetermined size, the specific gas is discharged to the molten pool by an operator's operation of a remote-controller. As the result, a molten base metal in the molten pool moves on a base metal by discharging the specific gas. It does not adhere to the base metal even if it solidifies on the base metal because of the large temperature difference against the molten base metal when the molten base metal in the molten pool moves over the base metal. Accordingly, when the work of moving the molten base metal in the molten pool by the specific gas (i.e., gouging work for the base metal) is repeated, the base metal can eventually be melted off (or fusion-cut).

A rotatable and removable connection for use in a welding torch assembly that allows for the gooseneck to be removeable and rotatable by the use of an interference member that allows the welding torch assembly to enter a locked, unlocked and partially lock state by moving the interface member about the central axis of the welding torch assembly, the partially lock state allows for rotation of the gooseneck without allowing for removal of the gooseneck, and the electrical connection provides electrical conduction via a conduction member that is independent form the locking features of the welding torch assembly.

The present invention relates to a welding torch including a mounting jig for mounting a wire-aiming guide which feeds a welding wire toward a molten pool of a work piece, wherein the mounting jig has a male screw that can be screwed into a female screw provided in a torch body, and is detachably mounted to the torch body; and a mounting jig. The present invention provides the welding torch with which a wire-aiming guide can be stably mounted and which can mount a highly versatile wire-aiming guide; and the mounting jig.

A torch-mounted power controller mounts to the handle of a welding torch and includes a control lever that is operated by the user's finger. The control lever is arranged to allow the user to hold the torch with a normal grip. Power supply to the welding torch is controlled by applying finger pressure to a control lever. A voltage control circuit is operatively connected to the control lever and controls the amount of power supplied responsive to the movement of the control lever.

The invention relates to a method and a welding torch for gas tungsten arc welding, wherein an electric arc burns between a non-consumable electrode (110) and a workpiece (151). The interior of the electrode (110) has a cavity (200) through which an electrically conducting filler (210) is fed in the direction (230a) of the workpiece (151), said filler (210) being energized.

A welding torch includes a head (3) having a body (11) bearing an electrode (13); an electric power source (27); and a filler metal wire (17) and a wire guide (19) guiding the filler metal wire (17) to the electrode (13). The body (11) is obtained by additive manufacturing from an electrically conductive metal, and the electrode (13) is electrically connected to the electric power source (27) by the metal constituting the body (11). The wire guide (19) includes an insulating sheath (29) inside which the filler metal wire (17) moves, and the filler metal wire (17) is electrically insulated from the potential of the body (11) by the insulating sheath (29).

A removable arc welding torch head having a variable electrode receiving aperture that includes a number of discrete, slidable wedges guided within a conical interior surface to enable the head to be used with electrodes of various diameters without changing components of the torch head. The removable nature of the torch, while providing for adequate flow of inert gas, provides an adjusting collar that engages the wedges and forms an adjustable opening for an electrode to be inserted therein.