Abstract: A resistance welding electrode body is fitted with a metal pin which serves as an anchor point for an electrode welding tip. The electrode welding tip contains two lead-in notches and diagonal grooves that allow the electrode tip to be locked onto the electrode body. This form of electrode has been found advantageous in terms of retaining the electrode tip onto the electrode body during resistance spot welding.

Abstract: In an electrode for welding with a retractable guide pin so received in a guide hole of the electrode that air blows out from a gap between the guide hole and the guide pin as the guide pin is pushed in to prevent intervention of foreign matters between an end face of an electrode and a steel sheet part or at a sliding portion of the guide pin, a large-diameter hole (33) and a small-diameter hole (34) are provided at a portion through which passes a small-diameter portion (7) of the guide pin (6) so as to form a receiving face (35) with the difference in diameter between the two, and an exhaust passage is provided near the receiving face (35) to establish communication between the large-diameter hole (33) and outside of the electrode.

Abstract: A method and apparatus of fusing a pin to a wire to reliably form a good quality fusion joint includes placing the pin and insulated or uninsulated wire in a notch of a lower fusing electrode so that the pin is spaced a predetermined distance above the wire. The upper fusing electrode applies fusing current and heat symmetrically to the pin and notch side walls and the portion of the lower electrode beneath and in contact with the wire. Heat is transferred to soften the pin and burn or vaporize the insulation off the wire before the pin and wire touch. Since all parts are held symmetrically, parts can not skew or burn off unevenly. Electrode pressure builds to drive the soften, heated pin and wire together and to apply fusing current through the contacting pin and wire to form a good fusion joint. Another aspect of the invention includes forming the lower fusing electrode with a plurality of fusing notches to afford quick operator set-up and sequential, automatic fusing of the series of wire/pin assemblies.

Abstract: For welding conductive materials, using conventional copper electrode caps, with a long service life of the welding tool, a foil section is provided between the electrode cap and the surface of the sheet. The foil section is part of a foil strip which is displaceable relative to the electrode cap, and consists of a material with a high nickel content, while silver or a silver metal oxide is provided as a material in the contact area between the electrode cap and the foil section. The electrode cap is preferably coated with this material.

Abstract: An electrode and a plasma arc torch are provided wherein the useful service life of the electrode is extended and the starting ability of the torch is improved because the arc is transferred from an initiation point to a final attaching point which is centered on the electrode. The electrode includes a generally cylindrical body defining a longitudinal axis and having a substantially planar front face that is perpendicular to the longitudinal axis. The front face has a central region at which the arc is to be supported after initiation of the arc. The front face further defines at least one groove extending radially inward for guiding the arc from the point of initiation along the front face toward the central region. Because the arc easily and quickly moves from its initiation point to the central region of the electrode along the groove, starting ability of the plasma arc torch is improved and service life of the electrode is lengthened.

Abstract: A test device (1) serves for impinging a sample (2) with a high-energy gas jet (3). A plasma torch (4, 5) provides the gas jet (3) heated by a plasma and directed towards the sample (2). A massive metal plate (6) is positioned in front of the sample (2). The metal plate (6) forms the opposing electrode for the plasma torch (4-6). A drive system (7) is provided for rotating the metal plate (6) about an rotational axis (9). The metal plate (6) is provided with a gap (11) exposing the sample (2) to the gas jet (3) when the metal plate (6) is in a certain rotational position about the rotational axis (9).

Abstract: A process is provided for forming a resistance welding electrode. The process includes the step of providing a billet formed from a high conductivity metal. The billet includes a first portion having a first inner cavity formed therein. The process further includes the steps of inserting a dispersion strengthened copper insert into the first inner cavity of the billet thereby forming an insert-containing billet, and deforming the insert-containing billet so as to mechanically lock the insert in place in the billet. The deformed insert-containing billet comprises the resistance welding electrode.

Abstract: In an electrode for a plasma arc torch, an electrode member (1) composed of either one of homologous elements of hafnium, zirconium or titanium, or a mixed material of these elements is embedded into a front end portion of an electrode body (1a) and brazed and joined thereto by a brazing material, the electrode is characterized in that the electrode member and the electrode body are brazed by a brazing material (14a) including no copper component.

Abstract: A terminal frame used to manufacture electronic devices, the terminal frame having a metal strip and a plurality of stick-like metal terminals. The metal terminals are joined to the metal strip by resistance welding. A manufacturing system of such terminal frames includes a device used for resistance welding, where the device has an electrode which holds each terminal at a portion near a joint portion, and a current is supplied to the terminal through the electrode.

Abstract: A resistance welding electrode for supplying a current to metal workpieces to weld the workpieces to each other includes an electrode body as an electrode matrix of a copper alloy and a plurality of filamentary members embedded in the electrode matrix parallel to the direction in which a current flows therethrough. The filamentary members have respective tip ends exposed as lands on a surface of a tip end of the electrode body. The filamentary members are made of a material having an electric conductivity different from that of the electrode matrix. The exposed tip ends of the filamentary members having a total area which is in the range of 0.5 to 40% of the entire area of the tip end of the electrode body.

Abstract: An electrode for supporting an arc in a plasma arc torch. The electrode includes a metallic holder having a front end, and a cavity in the front end, the cavity having an enlarged outer end portion. An insert assembly is mounted in the cavity and includes an emissive insert composed of a metallic material having a relatively low work function, a sleeve which substantially surrounds the emissive insert so as to separate the emissive insert from contact with the holder at least at the front end. The sleeve is composed of a metal which is selected from the group consisting of silver, gold, platinum, rhodium, iridium, palladium, nickel, and alloys thereof. The insert assembly further includes an aluminum face plate disposed in the enlarged outer end portion of the cavity and which is exposed at the front end of the metallic holder so as to surround a front portion of the sleeve. Alternatively, the aluminum face plate is eliminated and the front end of the metallic holder directly contacts the emissive insert.

Abstract: A method of repairing a spent electrode for a plasma arc torch. The method includes removing an end piece of the spent electrode thereby leaving an electrode base. A blind bore is drilled into the end face of the electrode base. Internal female threads are then formed in the blind bore. A bevelled angle is machined at the entrance of the blind bore. Finally, a replacement end piece having a matching bevelled angle and threaded male portion is mated with the bevelled angle and internal threads, respectively, of the blind bore in the electrode base, thereby forming a rebuilt electrode.

Abstract: A coolant tube for a liquid-cooled electrode disposed a plasma arc torch does not become damaged during an electrode blow-out condition. The coolant tube includes a hollow member and a substantially solid member. The hollow member has a first end, a second end and a coolant passage extending between the first and second ends. The first end can be secured within the torch such that the coolant tube is disposed adjacent the interior surface of the electrode and such that the coolant passage is in fluid communication with a coolant supply. The substantially solid member extends from the second end of the hollow member and has at least one flow restriction orifice extending therethrough. Each flow restriction orifice is fluid communication with the coolant passage for providing at least one high velocity jet of coolant to the interior surface of the electrode.

Abstract: A method and apparatus for spot welding a wire to a terminal where the core wires of the wire are not crushed or frayed and where the tensile strength of the connecting portion is improved. In the method of connecting the terminal and wire by spot welding, a concave groove (27a) corresponding to a section of the wire is formed in advance in the top end of a wire-side electrode (27) of spot welding electrodes. An exposed core portion (1a) of the wire is laid on the inner surface of a wire connection portion (13a) of the terminal, a section of which has been worked into a U-shape. While this overlaid portion is held between a terminal-side electrode (25) and the concave groove (27a) of the wire-side electrode (27), a current is supplied thereto under pressure. The apparatus includes the two electrodes including the wire-side electrode having a concave portion in which the wire is received as well as the opposing terminal-side electrode.

Abstract: An electrode for electric resistance welding comprises a guide hole of a circular cross-section composed of a small-diameter hole and a large-diameter hole, a guide pin composed of a small-diameter portion and a large-diameter portion, the small-diameter portion and larger-diameter portion of the guide pin being fitted into the small-diameter hole and large-diameter hole of the guide hole, respectively, so that when the guide pin is pushed down, compressed air is allowed to jet out of a gap between the small-diameter hole and the small-diameter portion. The large-diameter portion of the guide pin is firmly fitted into the guide hole, with an air passage formed in the outer circumference of the large-diameter portion and the end surface of the large-diameter portion seated on the inner end surface of the large-diameter hole.

Abstract: An electrode for supporting an arc in a plasma arc torch. The electrode includes a metallic holder having a front end, and a cavity in the front end, the cavity having an enlarged outer end portion. An insert assembly is mounted in the cavity and includes an emissive insert composed of a metallic material having a relatively low work function, a sleeve which substantially surrounds the emissive insert so as to separate the emissive insert from contact with the holder at least at the front end. The sleeve is composed of a metal which is selected from the group consisting of silver, gold, platinum, rhodium, iridium, palladium, nickel, and alloys thereof. The insert assembly further includes an aluminum face plate disposed in the enlarged outer end portion of the cavity and which is exposed at the front end of the metallic holder so as to surround a front portion of the sleeve.

Abstract: A plasma arc torch is provided which has a very long electrode lifetime, even if the number of times that an arc is generated and stopped is great. Improper electric discharge can be effectively prevented, and the lifetime can be increased due to the excellent resistance to heat. For this purpose, a metallic layer is provided in the portion where a pilot arc is generated, and the metallic layer contains at least one metal selected from the group consisting of gold and silver. The metallic layer is provided on the surface of the electrode holder, or on both of a surface of the electrode holder and a surface of the nozzle. Further, at least one of the electrode holder and the nozzle can be formed of aluminum or an aluminum alloy, and after the formation, an anodic oxide film can be formed on the surface thereof.

Abstract: A plasma torch electrode (132) comprises multiple platelets (159) oriented transverse to the electrode axis and joined together to form an electrical connection therebetween. A first group of the platelets have openings aligned to form an axial bore (164) for generating a plasma arc. A second group of the platelets define channels (172,178) aligned with each other, transverse to the electrode axis and in communication with the bore for injecting a gas, such as an inert gas, into the bore. In a specific embodiment, the plasma torch electrode comprises first and second end plates (152, 154) and a midplate (160), with the platelets stacked between and joined to the end plates and the central plate. This configuration allows precise fabrication of gas channels within the first and second sets of platelets while only requiring a small number of separate components to manufacture the plasma torch electrode.

Abstract: The elongated welding electrode is for plasma arc welding. It has a welding flux material coated on an elongated metal core. Gaps are formed in the flux coating and located at even intervals along the entire length of the electrode. The ratio of the melting points of the flux coating material and the metal core is in the range of 0.9 to 1.05. The ratio of the weights of the flux coating material and the metal core is in the range of 1.1 to 2.5. The electrode may be used with a simple welding gun and a large welding current to produce the plasma effect for welding without having to use an additional supply of gas for shielding the molten weld metal and for cooling the slag.

Abstract: A resistance welding electrode for supplying a current to metal workpieces to weld the workpieces to each other has an electrode matrix of a copper alloy and a plurality of members disposed in the electrode matrix and having portions exposed on a surface of a tip end of the electrode matrix. The members are made of a material having an electric conductivity different from that of the electrode matrix. The exposed portions of the members have a total area which is in the range of 40 to 82% of the entire area of the tip end of the electrode matrix.

Abstract: An insert securely disposed in a bottom end of an electrode has an exposed emission surface shaped to define a recess in the insert, wherein the recess is initially dimensioned as a function of the operating current level of the torch, the diameter of the insert, and the plasma gas flow pattern in the torch. The electrode has an elongated body formed of a high thermal conductivity material such as copper, and a bore disposed in the bottom end of the body along a central axis. The insert is formed of a high thermionic emissivity material, such as hafnium, and securely disposed in the bore with the emission surface exposed. The emission surface may be initially shaped by removing a predetermined amount of the high thermionic emissivity material from the insert to define a generally concave recess, a generally cylindrical recess or other shapes. When used in a torch, the electrode provides for reduced deposition of the high thermionic emissivity material on the nozzle, thereby reducing nozzle wear in the torch.

Abstract: A welding electrode for providing a significant improvement in the detrimental tensile residual stress condition on the root side of welds, especially on the inside wall of piping welds. The electrode has a tungsten alloy blade. The blade is made from sheets of tungsten alloy by cutting or stamping. The preferred shape of the blade is an isosceles triangle. The base of the flat triangular blade is secured in a slot formed in an electrode holder. The electrode holder is preferably T-shaped, with the shank of the holder being connected to a conventional welding torch. The holder is made of electrically conductive material, whereby the blade is coupled to the torch for producing an electric arc at the blade tip for welding. The blade is optionally covered with a ceramic coating to prevent arcing to the side walls of the groove formed between the parts being welded. A further option is to incorporate insulating stand-offs which protrude from both flat sides of the electrode blade.

Abstract: An electrode structure is composed of a gas passage containing a cathode ending in a cathode tip adjacent one end of the passage and has an anode electrode adjacent to the other end of the passage. A restriction is formed within the passage between the cathode and anode electrode to restrict the cross sectional area of the passage an accelerate the flow of gas from the cathode toward the anode and thereby increase the arc length and permit a reduced amperage to voltage (A/V) ratio for a given power input to the structure.

Abstract: A fuel rod for a nuclear reactor includes a metal cladding tube filled with nuclear fuel and having ends, an outer surface, and a longitudinal axis. A metal seal plug is welded to one of the ends of the cladding tube at a transition point, defining an annular bead on the outer surface of the cladding tube at the transition point. The annular bead has a cylindrical outer jacket surface with jacket lines being substantially parallel to the longitudinal axis of the cladding tube. The annular bead has material being formed of the metal of the cladding tube and the metal of the seal plug. A welding apparatus for producing a fuel rod includes an electrode having a through bore formed therein for receiving one end of a cladding tube. A counter electrode is displaceable relative to the electrode for holding a seal plug to be welded the one end of the cladding tube. The electrode has a cylindrical step formed therein at an end of the through bore facing toward the counter electrode.

Abstract: An insert securely disposed in a bottom end of an electrode has an exposed emission surface shaped to define a recess in the insert, wherein the recess is initially dimensioned as a function of the operating current level of the torch, the diameter of the insert, and the plasma gas flow pattern in the torch. The electrode has an elongated body formed of a high thermal conductivity material such as copper, and a bore disposed in the bottom end of the body along a central axis. The insert is formed of a high thermionic emissivity material, such as hafnium, and securely disposed in the bore with the emission surface exposed. The emission surface may be initially shaped by removing a predetermined amount of the high thermionic emissivity material from the insert to define a generally concave recess, a generally cylindrical recess or other shapes. When used in a torch, the electrode provides for reduced deposition of the high thermionic emissivity material on the nozzle, thereby reducing nozzle wear in the torch.

Abstract: An electrode for a plasma torch comprises multiple platelets that are stacked together. The platelets have openings that are oriented to form a bore through the electrode adapted for generating a plasma arc. The platelets also have apertures arranged to form multiple coolant channels through the electrode. The coolant channels are immediately adjacent to the bore and extend substantially along the entire length of the bore. This increases the heat transfer area between liquid coolant flowing through the channels and the hot plasma arc within the bore to reduce the temperature of the exposed electrode surface, thereby increasing the lifetime of the electrode. A second set of passages can exist within the electrode to inject gas through the electrode wall at the surface of the bore. This secondary gas injection is directed tangential to the bore surface to create or enhanced gas swirl, thereby rotating the arc foot and eliminating or reducing arc attachment induced erosion damage.

Abstract: An electrode and method of operating a plasma arc torch is provided which extends the useful service life of the torch. The electrode includes an elongate tubular holder defining a longitudinal axis and having a discharge end. An endwall closes the discharge end and includes an emissive insert. In one embodiment, the endwall also includes an annular sleeve which separates the insert from physical contact with the holder. Channels formed in the discharge end of the electrode direct a portion of a swirling vortex of gas across the surface of the endwall. The swirling vortex of gas removes products of erosion of the insert and adjacent portion of the sleeve such that the likelihood that arcing will transfer from the insert to the sleeve and/or holder is reduced, and the useful service life of the nozzle-electrode pair is thereby extended.

Abstract: A constrained chip for a plasma Jet torch is here disclosed, and the constrained chip is made of a metal, is forcedly cooled, and functions as one discharge electrode. A plasma generated by gas discharge is Jetted through a nozzle of the constrained chip for the plasma jet torch. This constrained chip 30 is all completely made of a Cu and Zr alloy, and a nozzle portion 32 has a nozzle bore diameter of 3.0 mm to 3.5 mm and a nozzle constraint ratio b/a (b is a length of the nozzle constrained portion) of 2.5 to 3.

Abstract: An electrode assembly having a tubular body portion is positioned in the head of a plasma arc torch and supports an electrode element spaced from a nozzle by an arc chamber. A gas is ionized in the arc chamber when an electric arc is initiated between the electrode element and the nozzle. The electrode element is retained in a post extending up from the bottom wall of the electrode body portion. The post has an extended exterior surface to increase the surface area in contact with coolant that circulates downwardly through the electrode body portion into surrounding relation with the post. The extended surface area of the post promotes heat transfer from the electrode element to the coolant and extends the operational life of the electrode element.

Abstract: A method of spot welding aluminum alloy workpieces having electrical conductivity of 18.about.57% IACS and Vickers hardness of 26.about.200 is disclosed. The aluminum alloy workpieces are spot welded by a pair of welding electrodes having an electrical conductivity of not less than 92% IACS and a Vickers hardness of 50.about.130. The differences of the electrical conductivity and Vickers hardness between the welding electrodes and the aluminum alloy workpieces are in a range of 41.about.87% IACS and not larger than 99, respectively.

Abstract: A spot welding electrode is made of a copper base material such as copper, copper alloy, or alumina dispersion strengthened copper, and has a Sn coating layer formed at the part making contact with the material being welded. The formed Sn coating layer reduces electrode wear and prolongs electrode life.

Abstract: A cutter for use in an electrode tip dresser, which has a cutter holder for holding the cutter and dresses an electrode tip for a resistance welding apparatus, has a rising portion which has a cutting tooth for cutting a front peripheral portion of the electrode tip and a flat portion which faces a front end surface of the electrode tip. The flat portion has a single cutting tooth for cutting the front end surface of the electrode tip. The single cutting tooth extends from that central point of the cutter as and origin which coincides with an axis of rotation of the cutter holder towards a predetermined radial direction. An origin portion of the single cutting tooth further extends beyond the central point towards a direction which is opposite to the radial direction.

Abstract: The diameter of a hafnium insert press fit into the bottom end of a copper electrode varies as a function of the level of current carried by the electrode. The diameter is the minimum necessary to support emission at that current level while also protecting the copper body against attack by the arc. The insert is generally circular and preferably extends completely through the bottom wall to a circulating flow of cooling water at a hollow interior of the electrode. The bottom wall includes an annular recess in a portion of the copper wall surrounding the insert. A coolant inlet tube extends into the recess in a spaced relationship to provide a high flow velocity of the coolant over the interior rear surface of the electrode.

Abstract: For resistance-welding workpieces of metal, an electrode is pressed against superposed regions of the workpieces and an electric current is supplied to the superposed regions to heat the same due to an electric resistance of the workpieces. The electrode has a body having a tip end for pressed engagement with one of the workpieces, and a matrix of tapered teeth disposed on the tip end of the body except for a center of the tip end. The teeth define recesses therebetween. One of the recesses is positioned at the center of the tip end, and the teeth are progressively higher from an outer circumferential edge of the tip end toward the center thereof.

Abstract: A gas cooled cathode for a direct current plasma torch. The cathode has a tip connected to a body. A gas passage for working gas passes through the body of the cathode, passes proximate the tip and exits the body adjacent the tip. The cathode is spaced apart from and insulated from the anode by means of a collar of insulation material.

Abstract: The invention relates to a process and a device for dressing truncated conical tips of electrodes in a spot welding gun, press or the like. According to the process, each electrode tip is dressed both on its truncated conical lateral surface on its end surface. In a first machining step, the electrode tip is inserted into a cavity in a first tool for machining the lateral surface or the end surface until the other of these two surfaces comes into contact with an abutment, whereafter the electrode tip in a second machining step is inserted into a cavity in a second tool for machining the end surface of the lateral surface until the surface which has been machined in the first machining steps comes into contact with an abutment. The device according to the invention comprises a motor driven, rotary tool for machining the truncated conical lateral surface and a second motor driven, rotary tool form machining the end surface of the electrode tip.

Abstract: A plasma arc cutting tip is provided having chamfer tip edge so that it can be easily moved and dragged across a workpiece for drag cutting and having counterbored plasma arc exit orifice which keeps the exit orifice off the workpiece so that the tip can tolerate plasma arc deflection without suffering tip damage or tip failure.

Abstract: An arc plasma torch having a tapered-bore electrode provides a long, columnar plasma arc. The torch includes a torch housing, a tapered-bore electrode, a gas-constricting nozzle, and a swirling gas flow generator.The electrode is mounted within the housing and has a closed inner end and an open outer mouth. The electrode has a longitudinally extending, tapered bore. The bore has its largest dimension at the mouth. The nozzle has a bore and is also mounted within the housing. The nozzle is in axial alignment with, forwardly spaced with respect to and insulated from, the tapered-bore electrode. The torch introduces a swirling flow of gas at a location intermediate the electrode and the gas-constricting nozzle, resulting in gas flowing past the electrode during use of the torch. In operation, an electric arc emanating from the electrode ionizes the gas flow.

Abstract: An electrode for a projection welding machine having a parts receiving hole is characterized in that a heat insulating element of magnetic material extending to the inlet side of the receiving hole is connected to a magnet disposed in the receiving hole and that the magnet itself is positioned adjacent a cooling hole.

Abstract: An enlarged and generally cup-shaped front section of the central passageway of the main body of the electrode has a rearwardly and inwardly sloping wall that extends at an angle within the range of approximately twenty to forty degrees relative to a plane perpendicular to the central axis of the electrode. The front section of the passageway has a readily replaceable and forwardly disclosed choke member having a central opening of a diameter within the range of 1.25 to 1.9 times the diameter of a rear section of the passageway. The rear section of the electrode passageway increases in diameter along a forward part of its length. The choke member comprises one of a set of similar choke members that differ from each other in the diameter of their central openings and/or in the electrically conductive material of which they are formed.

Abstract: An electrode for use in a plasma arc working torch having an insert of refractory metal inserted in the hollow formed in a base electrode is disclosed wherein the insert has a nickel film electroplated and a noble metal film plated thereon and is mounted in a pressed state. It is also disclosed that a metal having a low melting point is filled in a space defined by the hollow of the base electrode and the end face of the insert.

Abstract: A composite electrode (10) that is used for conducting a modulated voltage in a plasma reactor. An electrically conductive non-oxidizing surface and an electrically conductive metal surface are electrically and mechanically joined together by threads (12 and 13) to form a composite electrode (10). The composite electrode (10) is used to make contact between a wafer holder and the plasma reactor when the wafer holder is at rest in a chamber of the reactor.

Abstract: A cathode structure of a transition type plasma arc torch, in which a cooling effect is enhanced, and also an amount of consumption of cathode material is reduced by continuously moving a discharge point in the bottom end surface of the cathode during generating of a plasma arc. The cathode structure includes one cathode (21) of small-diameter circular column shape having a minute concave surface portion formed on its bottom end surface symmetrically with respect to its axis, a holder (20) for holding the cathode having such structure that easy and highly effective cooling is possible, and a generating device of lines of magnetic force (23) disposed coaxially with the aforementioned cathode (21) so that a line of magnetic force vector B such that E.times.B.noteq.0 may be fulfilled with respect to a line of electric force vector E generated on the bottom end surface of the cathode, may be generated symmetrically with respect to the axis of the cathode.

Abstract: A welding nose has a digital end and a root portion joined by a plurality of surface segments having a progressively increasing outside diameter for distributing welding loads in a radial direction and for forming a plurality of smooth surfaces joined at intersections to define preformed depressions for flow of metal grains from the base material of the welding nose for reducing formation of wings on the outermost diameter of the welding nose thereby to reduce sub-surface fracturing so as to maintain a desired mean diameter over extended periods of use.

Abstract: The service life of a bottom electrode for a direct current arc furnace for producing steel is prolonged by using ZrB.sub.2 type sintered bodies for a contacting pins which constitutes a major part of the bottom electrode wherein the ZrB.sub.2 type sintered bodies have a corrosion-resistance to molten steel and slag. Further, the number of contacting pins to be used is reduced by forming each of the pins into a form of pillar with a through hole at the axis, or by assembling a plurality of longitudinally divided pin portions to form a contacting pin, whereby the diameter of the contacting pin can be made large. Then the space between contacting pins is made broad, and brick having good corrosion-resistance are filled in the space so that the service life of the bottom electrode is brought closer to that of the refractory lining of the direct current arc furnace.

Abstract: Resistance welding electrodes and processes of using and of fabricating the same are provided. The electrodes have a base portion and an integral nose portion projecting therefrom, with the nose portion terminating in a welding tip face. The nose portion tapers inwardly between said base portion and said welding tip face with a concave profile taper such as a frustum of a vortical surface. The electrodes used may be made up of a conventional copper material having copper combined with one or more metals selected from the group consisting of chromium, zirconium, cadmium, cobalt, nickel, beryllium, tungsten, aluminum, tungsten carbide, iron, and molybdenum; or, may be made of essentially pure copper. The electrodes may be used in a welding process, which provides for a generally linear increase in current stepping with reduced or eliminated conditioning of the electrodes.

Abstract: Fusing apparatus and methods for fusing armature wires having an electrically insulating coating to the tangs of a commutator include a pair of spaced apart, side-by-side electrodes. The electrode pair are cojointly brought to bear on a common tang surface overlying an armature wire to be fused. The heat generated during the fusing process vaporizes the insulation on the armature wire to permit the fusing of the wire to the tang under controlled conditions.

Abstract: A plasma torch having an electrode with an insert disposed in an insert bore at one end and includes a vent to prevent high pressure cutting oil vapor generated by evaporation of cutting oil trapped in the cavity between the insert and the insert bore. The vent is a groove formed between the cavity and the outer surface of the electrode from pushing the insert out of the insert bore.

Abstract: The present invention relates to a plasma torch intended for being submerged into a bath of molten metal, such as for example a steel melt. The torch comprises an outer electrode made from a non-consumable material and an inner electrode, where at least the outer electrode is made from a copper pipe having internal channels for circulation of a cooling medium, said copper pipe at least on the outside having a layer of refractory material.The layer of refractory material has a thickness between 1 and 5 mm and is made from Al.sub.2 O.sub.3 or from ZrO.sub.2 stabilized with 5-25% by weight of MgO and/or Y.sub.2 O.sub.3 or oxides of other rare earth elements.