Abstract: A plasma arc torch includes an annular baffle defining distinct faces A, B, C, and D. Faces A and C are opposite from each other, and faces B and D are opposite from each other. First passages for fluid flow extend between the faces A and C, and second passages extend between the faces B and D. The baffle is installable in an annular space between an inner wall and an outer wall, in either of two orientations. In a first orientation, the first passages are open to fluid flow and the second passages are closed by engagement of the inner and outer walls with the faces B and D, and in a second orientation, flipped over relative to the first orientation, the second passages are open to fluid flow and the first passages are closed by engagement of the inner and outer walls with the faces A and C.

Abstract: A power supply, for a plasma cutter or a plasma arc welder, having a variable switching frequency and method of operating the power supply is generally disclosed. The power supply includes a switch for setting the switching frequency and a chopper control circuit for determining current output from the power supply, determining an operating frequency based on the determined current output and setting the switching frequency based on the determined operating frequency.

Abstract: A special-purpose plasma arc torch for gouging grooves in a metal workpiece includes an angled nozzle having a bore made up of a first bore portion and a second bore portion that makes an angle of about 15° to about 75° with the first bore portion. The nozzle includes a proximal portion and a distal portion, the proximal portion being adapted for surrounding an electrode assembly when the nozzle is installed in the torch, the distal portion being adapted such that a part of the distal portion extends beyond a front face of an electrode of the torch. The part of the distal portion extending beyond the front face of the electrode has an exterior shape other than cylindrical or conical, and preferably has a non-axisymmetric shape that makes it suitable for fitting within a deep groove in a workpiece.

Abstract: A head-mix swirl injector for gas torches. The swirl injector may include an injector body adapted to be disposed in a head of the torch. The injector body may define a swirl baffle, an injector orifice in fluid communication with the swirl baffle, and a mixing chamber in fluid communication with the injector orifice. The swirl injector may further include at least one gas port extending from the mixing chamber to an exterior of the injector body. The mixing chamber may have a larger diameter than the injector orifice.

Abstract: A front end assembly for a plasma torch and methods for assembling and disassembling a torch wherein a plurality of front end parts form a unit that is removable from, and installable in, the torch in a single operation without a special fixture. The front end assembly includes a nozzle retaining cup body connectable to a body of the torch, and a forward end connectable to a shield retainer. A nozzle retaining cup insert fits into the nozzle retaining cup body. The shield retainer has an inner surface for retaining the shield. A nozzle is received within the nozzle retaining cup insert. A stop on the nozzle engages the nozzle retaining cup insert when the front end assembly is removed from the torch so the nozzle does not remain in the torch. The shield engages an insulator, which engages the nozzle, to limit forward axial movement of the nozzle.

Abstract: An electrode is disclosed for use in MIG/MAG welding. The electrode comprises an elongated electrode body within which is embedded a metallic filament. In some embodiments, the filament is copper, and is offset from the center of the electrode body. A method is disclosed for forming an electrode. The method may include removing oxidation from a surface of an electrode body, forming the electrode body to a desired size and geometry, removing lubricants from the surface of the electrode body, forming an elongated channel in a surface of the electrode body, depositing a filament in the elongated channel, and forming the electrode body over the filament. Other embodiments are disclosed and claimed.

Abstract: A self-shielded flux cored arc welding electrode is disclosed including a ferrous metal sheath and a core within the sheath enclosing core ingredients comprise a composition window of aluminum, manganese and rare earth metals in wires of about 2.0-3.0 wt. % [Al], 1.0-2.0 wt. % [Mn] and 0.001-0.11 wt. % rare earth metals or 0.001-0.5% rare earth metal oxides, such as, but not limited to, La, Ce, etc. Resulting welds include 0.7-1.0 wt. % [Al] and 1.1-1.5 wt. % [Mn]. Resulting welds have a maximum diffusible hydrogen content of 5 mL/100 g or less, Resulting welds also have a Charpy V-notch toughness at ?40° F. of at least 100 ft-lbs.

Abstract: A plasma arc torch includes an annular baffle defining distinct faces A, B, C, and D. Faces A and C are opposite from each other, and faces B and D are opposite from each other. First passages for fluid flow extend between the faces A and C, and second passages extend between the faces B and D. The baffle is installable in an annular space between an inner wall and an outer wall, in either of two orientations. In a first orientation, the first passages are open to fluid flow and the second passages are closed by engagement of the inner and outer walls with the faces B and D, and in a second orientation, flipped over relative to the first orientation, the second passages are open to fluid flow and the first passages are closed by engagement of the inner and outer walls with the faces A and C.

Abstract: A system for supplying fluids to a plasma arc torch includes a single-gas power supply for regulating electrical power to the torch and for regulating supply of a first fluid to the torch, a flow regulator for regulating supply of a second fluid to the torch, and a first pressure-actuated valve disposed between the flow regulator and the torch. The valve shuts off supply of the second fluid to the torch when the first valve is closed and allows the second fluid to be supplied when the first valve is open. The first valve is opened by pressure of the first fluid supplied to the torch and closed when the first fluid is not supplied to the torch. A second pressure-actuated valve may be provided in the supply line for the first fluid, which is opened by pressure of the second fluid being supplied to the torch.

Abstract: A method of welding a joint includes directing a first output from a high energy density heat source, such as a laser, against a first side of the joint. The method further includes directing a second output from an arc welding heat source, such as a gas metal arc welding torch, against a second side of the joint. The first output produces a keyhole surrounded by a molten metal pool which extends from the first side of the joint toward the second side of the joint. In some embodiments a third output from a second arc welding heat source may also be directed at the first side of the joint. A second molten metal pool produced by the arc welding heat source joins with the first molten metal pool and the third molten metal pool to form a common molten metal pool which solidifies to form the weld.

Abstract: Embodiments of the present invention are related to an electrode for a plasma arc torch, the electrode comprising a generally tubular outer wall, an end wall, and a protrusion. The end wall is joined to a distal end of the outer wall and supports an emissive element in a generally central region. The protrusion extends from the generally central region of the end wall and is configured to connect with an electrode holder by a releasable connection, wherein the protrusion is configured such that at least one coolant passage forms between the protrusion and the electrode holder when the electrode is connected with the electrode holder. In some embodiments, the releasable connection comprises a threaded connection, wherein the protrusion is threaded to releasably connect to a threaded coolant tube of the electrode holder. In other embodiments, at least one coolant passage is defined by the threaded connection.

Abstract: A gas-shielded flux cored welding electrode comprises a ferrous metal sheath and a core within the sheath enclosing core ingredients. The core ingredients and sheath together comprise, in weight percentages based on the total weight of the core ingredients and the sheath: 0.25 to 1.50 manganese; 0.02 to 0.12 carbon; 0.003 to 0.02 boron; 0.2 to 1.5 silicon; 0 to 0.3 molybdenum; at least one of titanium, magnesium, and aluminum, wherein the total content of titanium, magnesium, and aluminum is 0.2 to 2.5; 3 to 12 titanium dioxide; at least one arc stabilizer, where the total content of arc stabilizers is 0.05 to 1.0; no greater than 10 of additional flux system components; remainder iron and incidental impurities.

Abstract: Embodiments of the present invention are related to an electrode for a plasma arc torch, the electrode comprising a generally tubular outer wall, an end wall, and a protrusion. The end wall is joined to a distal end of the outer wall and supports an emissive element in a generally central region. The protrusion extends from the generally central region of the end wall and is configured to connect with an electrode holder by a releasable connection, wherein the protrusion is configured such that at least one coolant passage forms between the protrusion and the electrode holder when the electrode is connected with the electrode holder. In some embodiments, the releasable connection comprises a threaded connection, wherein the protrusion is threaded to releasably connect to a threaded coolant tube of the electrode holder. In other embodiments, at least one coolant passage is defined by the threaded connection.

Abstract: A plasma arc torch is provided that includes a wear stop designed to detect wear of an electrode and prevent the use of the electrode once the electrode has experienced a certain amount of wear. Either the electrode or the nozzle is movable with respect to the main torch body, and the movable component defines a projection. The wear stop is positioned a predetermined distance from a nozzle of the torch, such that prior to experiencing an excessive amount of wear, the electrode is able to contact the nozzle and initiate a pilot arc for starting a torch operation. Once the length of the electrode becomes shorter than a predetermined length due to wear, the projection of the electrode engages the wear stop, and the wear stop prevents the electrode from contacting the nozzle. In this way, an electrode that is excessively worn cannot be used in subsequent torch operations.

Abstract: An improved plasma torch and method of starting the torch are provided. The torch may comprise a main torch body with an electrode assembly coupled to a piston therein. The piston and electrode assembly are moveable between a starting position whereby the electrode assembly contacts a nozzle, and an operating position whereby the electrode assembly does not contact the nozzle. The piston is moveable by directing fluid, which may comprise coolant, through the plasma torch either in a first direction which biases the piston to the starting position, or in an opposite second direction which biases the piston so as to retract the electrode assembly to the operating position. A reversing valve or reversible pump may be used to control the direction of the flow of the fluid. Thereby, the coolant supply may be used to both cool the torch and control the starting and operation of the torch.

Abstract: A plasma arc torch includes an annular baffle defining distinct faces A, B, C, and D. Faces A and C are opposite from each other, and faces B and D are opposite from each other. First passages for fluid flow extend between the faces A and C, and second passages extend between the faces B and D. The baffle is installable in an annular space between an inner wall and an outer wall, in either of two orientations. In a first orientation, the first passages are open to fluid flow and the second passages are closed by engagement of the inner and outer walls with the faces B and D, and in a second orientation, flipped over relative to the first orientation, the second passages are open to fluid flow and the first passages are closed by engagement of the inner and outer walls with the faces A and C.

Abstract: A head-mix swirl injector for gas torches. The swirl injector may include an injector body adapted to be disposed in a head of the torch. The injector body may define a swirl baffle, an injector orifice in fluid communication with the swirl baffle, and a mixing chamber in fluid communication with the injector orifice. The swirl injector may further include at least one gas port extending from the mixing chamber to an exterior of the injector body. The mixing chamber may have a larger diameter than the injector orifice.