Abstract: A device and a method of manufacturing a metal tube made from a metal sheet with two substantially straight and parallel longitudinal edges, in which method the two longitudinal edges of the metal sheet are welded together using a welding method employing at least one electric arc between at least one electrode (Ei) and the metal sheet in contact with at least one ground lead (PMi), in which the plane of each ground lead (PMi) is positioned a distance (e.sub.i) of between -5 mm and +25 mm with respect to the plane of each corresponding electrode (Ei), the positive direction being the direction of relative travel of the metal sheet with respect to the at least one electrode (Ei).

Abstract: The invention is a welding parameter control device for a welding torch operable by the welders thumb and/or index finger. A forward-located rotary knob or belt is positioned where the torch is of relatively small diameter and comfortable for the welder to hold in the hand. This is coupled to a rotary potentiometer located toward the rear portion of the torch. Here the torch diameter can be increased without discomfort to the welder. By placing the potentiometer in this position it can be much larger and more rugged than would be possible if located at the position of the control knob. In contrast to the use of a highly miniaturized potentiometer at the control point location, failure rate is greatly reduced. Weld disturbance due to torch movement during current adjustment is virtually eliminated by use of the fingertip operated rotary control.

Abstract: A TIG welding apparatus comprises a welding current supply means for supplying an electric current, a shield gas supply means for supplying shield gases, a tungsten electrode connected to the welding current supply means, a welding torch disposed coaxially around the tungsten electrode and provided with inner and outer double gas shields having gas jetting nozzles through which the gases are jetted, a plurality of wires to be fed to a portion at which the gases are jetted through the gas jetting nozzles, a wire feeding means, and a heating means connected to the wires, except at least one wire, for heating the wires.

Abstract: The invention concerns a gas lens housing (20) for arc-welding or flame cutters with a non-melting electrode (4), in particular for T.I.G. welding. According to the invention, a torch member (1) comprises a housing (2) for accommodating an electrode holder (3) which optionally comprises in a front, downstream section (26) collets (28) with expansion slots (8) for clamping the electrode (4) in place. An annular duct (24) used as a protective gas duct is formed between the electrode holder (3) and a housing casing (22) and a gas lens (6) is disposed in the annular duct (24) or torch nozzle (5). The gas lens housing (20) is mounted with play at a front end (30) of the electrode holder (3).

Abstract: An assembly for welding includes a frame member and a plurality of repositionable torches supported by the frame member adjacent a linear path of travel of a metal strip. The method includes the steps of welding the metal strip, ascertaining the character of the weld and repositioning the torches to alter the character of the weld.

Abstract: In order to provide a plasma burner comprising a fluid-cooled anode and a cathode, wherein an arc can be produced between the cathode and the anode in a combustion chamber and a burner gas can be passed through the combustion chamber to form the plasma, in such a way that it can be produced cost-effectively and used universally, it is proposed that the plasma burner should have coolant passages for applying coolant to the anode, the coolant passages being arranged and constructed so that they can be made by machining and are free from soldered joints.

Abstract: A plasma torch provided with an electrode (1) having an approximately cylindrical or frustocylindrical elongate shape, the electrode (1) including at least one recess (9) made in at least part of its external peripheral wall (15). In order to deflect and guide the gas flux entering the plasma torch, the recess (9) in the electrode (1) lies opposite the orifice or orifices (7) for introducing or injecting the gas flux into the torch.

Abstract: The plasma torch produces a transferred arc and has only one electrode integrated in the torch with the counter electrode being provided by the material being treated. The torch includes an outer housing (3), a single hollow electrode (5) arranged in the outer housing (3) and a gas vortex generator device (7) connected with the electrode. The gas vortex generator device (7) includes a rotationally symmetric ring (R) provided with at least two rows of throughgoing holes (10) axially spaced from each other and an impact wall (P) associated with an upper row of the throughgoing holes, so that a satisfactory two-part gas vortex flow is formed. By varying the gas pressure in an oscillating manner, the spot of the arc is continuously displaced in an axial direction (A). An additional gas feed (8) is provided so that gas can be fed axially directly to the plasma jet.

Abstract: Disclosed is a novel method and structure for contact starting a plasma arc torch. A translatable, electrically conductive component such as a nozzle or swirl ring is biased into contact with an electrode by a compliant spring element. A pilot arc is formed by first passing current through the electrode/component interface. Thereafter, the component is translated under the influence of gas pressure in a plasma chamber formed between the electrode and component, compressing the compliant element and initiating the pilot arc. The spring element may be a separate element or may be maintained integrally with the nozzle, swirl ring, or a retaining cap, facilitating removal and replacement of the spring element with consumable components of the torch.

Abstract: An integrated non-consumable electrode and filler material nozzle for use with electric arc welding (or arc brazing). The electrode and filler nozzle are preferably integrated in one or more of the following ways: mechanically, thermally or electrically. The filler nozzle may be used to feed either hot or cold wire. Electric arc power and the wire resistance-heating power may be supplied by a single arc welding power supply, which is either directly or indirectly shunted between the electrode and filler nozzle. The nozzle can be designed to feed either single or multiple filler wires. The hot-wire nozzle preferably has a movable contact element which allows the electrical extension to be adjusted. Also the curvature of the outlet end of the hot-wire nozzle can be adjusted. If the nozzle is vertical, a wire deflection device at the nozzle outlet can be used to deflect the tip of the filler wire toward the weld puddle.

Abstract: An improved method of arc welding uses a single power supply connected to opposed welding torches placed on both sides of a workpiece. Each torch is connected to a different polarity lead of the power supply and forms a separate arc with the workpiece. When a current is supplied to the first torch, it is guided from the first electrode, through the first arc, the workpiece, the second arc, and to the electrode of the second torch. This guiding function improves the penetration, concentration, as well as the directional stability of the arc. This permits the effective and efficient welding of relatively thick workpieces using existing equipment at low current levels.

Abstract: An apparatus for emitting a laminar flow of inert gas at a location inside a reduced-width, high-aspect-ratio (ratio of depth to width) weld groove. The portion of the gas distribution apparatus extending into the groove has a thickness less than the width of the weld groove and distributes inert gas which displaces the ambient atmosphere overlying the molten pool area at the bottom of the weld groove. The gas distribution apparatus may take the form of a tube, a planar array of mutually parallel tubes joined at the sides, a monolithic block having an elongated cross section with a parallel array of channels drilled or machined therein, or a support frame covered by a gas-permeable skin. To achieve a laminar flow, a gas diffusing structure is incorporated in each gas distribution tube.

Abstract: A plasma arc torch includes a torch body and a nozzle mounted relative to an electrode at a first end of the torch body to define a plasma chamber. The torch body includes a plasma gas flow path for directing a plasma gas from a plasma gas inlet to a plasma chamber in which a plasma arc is formed. The nozzle includes a hollow, body portion defining a cavity and a substantially solid, head portion formed integrally with the body portion defining an exit orifice extending from the chamber. The exit orifice has a converging inlet and an outlet, where the inlet has a radius of curvature, and the exit orifice has a length to diameter ratio of greater than 2.5.

Abstract: A guide nozzle for feeding multiple fusible filler metal wires into reduced-width, high-aspect-ratio (ratio of depth to width) metallic joints with control and stability of the filler metal position as it enters the molten pool area. The multiple filler wires are fed concurrently at the same or different feed rates. The guide nozzle is fabricated by flattening a circular tube into an oval or elliptical shape. In the case when the filler wires have the same diameter, the resulting oval or elliptical hole in the guide nozzle has a height greater than two times the diameter of the filler wires and a width greater than one diameter but less than two times the diameter of the filler wire. Alternatively, the guide nozzle is formed by forming a flat side on each of two circular tubes and then joining the flat sides together. Each tube has a circular hole of diameter greater than the diameter of the filler wire to be guided therein.

Abstract: A welding method in which the outer-most surfaces of ferritic stainless steel contains chromium oxide surfaces with no iron oxides. The welding method includes flowing a gas having an oxidizing activity over the welded part while applying an arc to the welded part, which is insufficient to melt the welded part. The resulting welded stainless steel is suitable for use as clean room gas supply lines.

Abstract: The present invention relates to a method for welding comprising the steps of: contacting a plurality of workpieces to be welded having different heat capacities so as to form a boundary portion therebetween; placing a welding electrode in proximity to the boundary portion; generating an arc discharge between the welding electrode and the boundary portion; and supplying gas to the boundary portion, wherein more gas being supplied to one of the workpieces having a lower heat capacity than another workpiece having a higher heat capacity.

Abstract: A plasma torch comprises a tubular nozzle having an end wall and an electrode in the nozzle having a nose end facing the end wall. The nose end and end wall provide a plasma gas chamber, and the end wall has a gas chamber outlet opening extending axially therethrough. The gas chamber has an entrance radially outwardly of the outlet opening and the end wall has a plurality of arcuate ribs thereon circumferentially spaced apart about said outlet opening and providing a plurality of arcuate gas directing channels for radially guiding the flow of plasma gas in a swirling flow pattern from the entrance to the outlet opening. The nozzle and nozzle mounting components provide an improved arrangement for cooling the torch tip and producing a gas shield about the plasma jet.

Abstract: An inert gas electric arc welding process is described in which the refractory electrode of the welding torch is rotated about its own axis throughout the welding operation so that the electric arc produced at the end of the electrode rotates and agitates the surface of the melt pool locally and continuously.

Abstract: There is provided a plasma torch in which a plasma arc emanating from an electrode in a torch body (1) is pinched in a torch nozzle (3) and is then flushed therefrom, characterized in that an axis of said torch nozzle (3) is deviated in position from with a center line of said torch body (1).

Abstract: A hot-wire nozzle for feeding pre-heated filler material into a welding groove. The nozzle has a contact tube made of electrically conductive material surrounded by a thin structural outer sheath. The outer sheath is electrically insulated from the contact tube by means of layers of electrically insulating material sandwiched between the contact tube and the outer sheath. The contact tube is configured to feed two or more filler wires simultaneously.

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 plasma arc torch comprises relatively displaceable electrode and nozzle components having first and second positions relative to one another in which the electrode respectively contacts the nozzle and is spaced an operating distance therefrom. Arrangements are disclosed for relatively displacing the electrode and nozzle between the first and second positions thereof with a pre-determined force of engagement therebetween in the first position, and without having to interrupt the flow of arc gas and/or the flow of arc current during such relative displacement. A torch start up safety test procedure is performed by sequentially displacing the electrode and nozzle between the two positions thereof, sensing for appropriate open and closed circuit conditions therebetween, and enabling the creation of a pilot arc only when a pre-determined sequence of circuit conditions is sensed.

Abstract: A torch for cutting, gouging or welding metal including a body having a central longitudinal axis for connection to sources of pressurized gas and electrical potential and a swivel housing threadably connected to the body for rotation relative to the body about the axis and a tubular handle around the body and the swivel housing. The handle has front and rear sections manually relatively rotatable. The front section and swivel housing are rotatable as a unit, and the rear section and body are rotatable as a unit so that rotation of one section relative to the other effects rotation of the swivel housing relative to the body. The torch includes a head forward of the swivel housing having an opening for holding an electrode and includes an elongate unitary swivel member having a forward end non-rotatably attached to the head and a rearward swivel end disposed in an opening of the swivel housing.

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 plasma arc torch which has a cooling water passage for cooling both the electrode and the nozzle, and separate passages for a cutting gas and a shielding gas. The nozzle is centered and longitudinally held by an interengaging fit with a tubular member of the torch body, and the torch includes a heat shield assembly which retains and supports the nozzle of the torch on the tubular member. The heat shield assembly also defines a portion of the cooling water passage as well as a portion of the shielding gas passage, and it may be unthreaded and removed from the torch as a unit. When so removed, the water passage is opened which acts to disconnect the power to the torch.

Abstract: Disclosed is a novel method and structure for contact starting a plasma arc torch. A translatable, electrically conductive component such as a nozzle or swirl ring is biased into contact with an electrode by a compliant spring element. A pilot arc is formed by first passing current through the electrode/component interface. Thereafter, the component is translated under the influence of gas pressure in a plasma chamber formed between the electrode and component, compressing the compliant element and initiating the pilot arc. The spring element may be maintained integrally with the nozzle, swirl ring, or a retaining cap, facilitating removal and replacement of the spring element with consumable components of the torch. Exemplary spring elements include wave spring washers, finger spring washers, curved spring washers, helical compression springs, flat wire compression springs, and slotted conical discs.

Abstract: A plasma torch comprises a tubular nozzle having an end wall and an electrode in the nozzle having a nose end facing the end wall. The nose end and end wall provide a plasma gas chamber, and the end wall has a gas chamber outlet opening extending axially therethrough. The gas chamber has an entrance radially outwardly of the outlet opening and the end wall has a plurality of arcuate ribs thereon circumferentially spaced apart about said outlet opening and providing a plurality of arcuate gas directing channels for radially guiding the flow of plasma gas in a swirling flow pattern from the entrance to the outlet opening. The nozzle and nozzle mounting components provide an improved arrangement for cooling the torch tip and producing a gas shield about the plasma jet.

Abstract: A welding torch (10) for gas tungsten arc (tungsten inert gas) welding includes a housing (12) and an electrode holder (50, 52) which is mounted on the housing so as to project therefrom, and which is adapted to hold an electrode (54) such that the electrode projects from an end of the holder remote from the housing. A shroud (14) is mounted on, or forms part of, the housing (12) and extends around but is spaced from the electrode holder (50, 52). Electrically conductive means (46, 48) extends within the housing (12) for electrically connecting the electrode holder (50, 52) to one terminal of an electric power source. The torch (10) is adapted for connection to a source of an inert gas for generating a flow of gas through the shroud (14), around the electrode holder (50, 52).

Abstract: A narrow groove welding apparatus including a torch assembly with a replaceable gas cup so that different length gas cups can be used for different depth grooves. An adjustable support assembly is provided to permit corresponding positioning of auxiliary components, including visual monitoring assemblies, wire feed assemblies, and illumination assemblies to ensure proper alignment of the auxiliary components with the weld zone. A torch assembly permits ready replacement of electrodes to match gas cups, and electrically isolates the electrode from the gas cup.

Abstract: A translatable nozzle is supported in a contact start plasma arc torch at an aft end by a swirl ring and at a longitudinally spaced forward end by an insulative bearing member of a nozzle retainer. The nozzle is biased into contact with an electrode by a compliant spring element. A pilot arc is formed by first passing current through the electrode and nozzle. Upon pressurization of a plasma chamber formed therebetween, the nozzle is translated forward, compressing the spring element and initiating the pilot arc. The spring element may be maintained integrally with the nozzle to facilitate removal and replacement of the spring element with the consumable nozzle.

Abstract: An indirect cooling system suitable for a plasma jet cutting method is established to prevent the leakage of cooling water and to enable a stable plasma jet to be obtained. A tip having a nozzle for emitting a plasma jet is fitted to a nozzle sleeve through which cooling water circulates, and electric discharge is induced between the tip and an electrode extending through the nozzle sleeve to the neighborhood of the tip, thereby ionizing a neutral gas and emitting a plasma jet through the nozzle. In the indirectly-cooled plasma jet torch, the tip is brought into surface contact with the nozzle sleeve to fit them to each other, and contact portions of the tip and the nozzle sleeve are tapered.

Abstract: A processing torch having a separably assembled torch base and torch head includes a first ring member rotatably provided on an outer periphery of one of the torch base and the torch head, and a second ring member fixed on the other one of the torch base and the torch head. An engaging projection is provided on one of the first and second ring members, and an inclined track provided on the other of the first and second ring members for engaging with the engaging projection. In addition, an elastic biasing member is provided for increasing an engaging force between the inclined track and the engaging projection so as to sealingly engage the inclined track and the engaging projection. Connection and disconnection between the torch base and the torch head are performed by rotation of at least one of the first and second ring members.

Abstract: This invention relates to a plasma torch with electrode air-cooling devices, comprising:a hollow electrodesystems designed to introduce cooling air into the electrode near the tip, which systems consist of a tubular element smaller than the hole in the electrode so as to form a cavity between the inner wall of the electrode and the tubular elementpassages designed to place the top of the electrode in communication with a ring-shaped chamber inside the torch body which surrounds the electrodepassages situated in the torch body which are designed to place the said ring-shaped chamber in communication with the area surrounding the hoodpassages designed to place the said ring-shaped chamber in communication with the plasma chamber.

Abstract: A drag cup for a plasma arc torch is mounted on a sleeve member of the torch tip having a conical outer surface portion converging toward the torch nozzle and electrode assembly. The drag cup includes a mounting end, a conical portion extending along the conical portion of the sleeve member, and an end radially spaced from and surrounding the torch nozzle and including an end wall spaced axially outwardly of the end of the nozzle and having an opening therethrough coaxial with the plasma jet outlet orifice in the nozzle. The opening through the end wall of the drag cup is 3 to 6 times the size of the nozzle orifice and is large enough to provide a shielding gas flow about the plasma jet without disturbing the jet and, at the same time is small enough to protect the nozzle against molten metal blow-back through the opening.

Abstract: A novel plasma gun having a gas distribution plug which enhances the circumferential velocity component of the plasma gas. The gas distribution plug has a bore with a greater circumferential component proximate the gas egress end then at the gas ingress end.

Abstract: Fixed welding apparatus includes a torch body, a pusher rod, a reverse collet, and a collet. The pusher rod is slidably received within an opening formed through the torch body. A portion of the reverse collet is positioned in an opening formed in the pusher rod. The collet is attached to the torch body and contacts with the reverse collet. The torch body also may include at least one notch formed in its side to receive a retractable arm member, which slidably fits in the notch. The fixed welding apparatus may also include a torch housing, an adjusting knob and shaft, a beveled gear set attached to the shaft, an adjusting screw attached to the gear set, and an indicator block which attaches to the retractable arm.

Abstract: A filler material guide nozzle assembly for feeding fusible filler metal wire or other metal forms into reduced-width, high-aspect-ratio (ratio of depth to width) metallic joints with control and stability of the filler metal position as it enters the molten pool area. The filler material guide nozzle assembly is designed with a thin but stiff non-circular cross-sectional shape, with its width dimension significantly greater than its thickness dimension, and can be utilized in very reduced-width welded or otherwise fused joints to provide the accuracy and stability required for reliable filler material addition. During use with welding, brazing and similar processes, the outlet end of the nozzle is located within the joint near the bottom, close to the area to be fused. The width dimension of the nozzle apparatus is oriented parallel to the depth of the weld joint, and the thickness dimension is oriented perpendicular to the depth of the joint.

Abstract: A semi-automatic TIG welding apparatus including a torch handle, a wire-feeding curved nozzle which is disposed within the torch handle and is curved at a point slightly extended from the torch handle, and a TIG torch supporting arm which is fixed to a TIG torch having a shielding gas hose and center gas hose. An inside portion of the TIG torch supporting arm is formed of an electroconductive material. The apparatus further includes water-cooling welding cable hoses which are attached to a water tank, extend through the inner side of the torch handle, and are attached to the TIG torch. The water-cooling welding cable hoses being formed with electroconductive cables provided therein. The apparatus may additionally include a TIG torch rotation block which is rotatably mounted to the wire-feeding curved nozzle and fixed to the TIG torch supporting arm.

Abstract: A gas lens assembly for an arc welding torch includes a lens body having a rearward end and a forward end, a passage through the lens body from its forward end to its rearward end for receiving an electrode therethrough and for permitting flow of an inert gas in a forward direction in the passage. A lens housing is secured to the lens body and defines a chamber around a forward end portion of the lens body. One or more openings in the forward end portion of the lens body enable the inert gas to flow from the passage into the chamber. The gas lens assembly further includes a flow control device associated with the housing through which said inert gas is adapted to flow in a forward direction. The flow control device controls the flow of the inert gas therethrough so that the gas exists the flow control device as a laminar stream of gas moving in a forward direction. The laminar stream is adapted to blanket a weld puddle during a welding operation on a workpiece.

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 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 plasma arc torch is provided with an extended water-injection nozzle assembly characterized by the ability to produce a bevel cut or weld, and a cut or weld within a concavity on the top surface of a workpiece. The nozzle assembly includes a nozzle base, a swirl ring and an outer shell press-fit together to center and maintain the concentricity of the water-injection bore of the outer shell relative to the gas-constricting bore of the nozzle base. A radially exterior, frusto conical surface of the nozzle base and a radially interior, frusto conical surface of the outer shell define a fluid passageway therebetween for communicating a vortical flow of cooling fluid from an external source to the water-injection bore of the outer shell. Preferably, the vortical flow of cooling fluid further constricts the plasma arc extending outwardly from the electrode and along the longitudinal discharge axis defined by the plasma arc torch in the direction of the workpiece.

Abstract: The shielding gas mixture for the TIG or GTAW arc welding of stainless steels, in particular of duplex or super duplex steels, comprises, in argon, from 3 to 18%, advantageously approximately 10%, of helium and from 1 to 3%, advantageously approximately 2%, of nitrogen. This gas mixture makes it possible to ensure good corrosion resistance of the metal deposited, acceptable solidity of the welds and excellent arc stability, as well as a suitable viscosity of the molten metal appropriate to manual welding in all positions.

Abstract: The plasma torch head comprises an axial electrode (10) with a flat end surface (16) associated with a cup-shaped peripheral nozzle (12). The bottom (20) of the nozzle (12) comprises an axial conduit (22) for ejection of the plasma jet, and its lateral wall (24) surrounds the electrode (10) and delimits with this latter a substantially annular supply space (26). The torch head comprises structure (38) for the flow of a plasmagenic gas in the annular supply space (26) in a substantially axial direction. The end surface (16) of the electrode (10) delimits with the bottom (20) of the nozzle (12) an annular space (29) for lamination of the flow of the plasmagenic gas. For use in plasma cutting torches.

Abstract: A plasma torch of swirling plasma gas flow type is disclosed in which there are provided an electrode body having a forward end thereof and a nozzle that is arranged to enclose said forward end portion of the electrode and that is spaced therefrom across a plasma gas flow passage, characterized in that at least a portion of the said electrode body at which a pilot arc can be ignited is composed of either of a material that is high in its melting point and a mixture of the said high melting point material with either of a substance that is low in its work function and an oxide of the said substance.

Abstract: A plasma torch comprising an elongated electrically conductive nozzle with an internal, generally cylindrical chamber; an electrically conductive electrode with an elongated, cylindrical nose extending into the cylindrical chamber of the nozzle to define a relatively thin, elongated annular gas passage between the nozzle and the electrode nose, wherein the electrode includes a cylindrical portion above the nose, which portion has axially extending swirl grooves; and, a separate insulator sleeve engaging both the cylindrical portion and the nozzle for holding the electrode nose concentric with said cylindrical chamber of the nozzle. The nozzle includes means for venting a portion of said cooling gas from the relatively thin annular gas passage.

Abstract: A joint for plasma arc cutting torches comprising a fixed female element, to be applied to the generator, and a movable male element, being connected to the torch, which can be fitted into said fixed element and is provided with a ring (5) which can be screwed on said fixed element, and a sleeve (11) engaging said ring, means (15, 16), which can be disengaged by a tool, being provided for engaging said sleeve in order to prevent its rotation.

Abstract: The electric-arc plasma-steam torch has a housing accommodating coaxially arranged therein a nozzle anode and a cathode made fast in a holder. The housing communicates, via a pipe connector filled with a porous heat-conducting material, with a container. The container is filled with a moisture absorbent material which encompasses a tube running therethrough and made of a heat-conducting material. The tube has a flange at its end facing the nozzle anode. The flange is provided with passages on its end surface facing the nozzle anode. The aforementioned cathode holder is accommodated in the tube and is electrically insulated therefrom. A sleeve made of a heat-conducting material is interposed between the nozzle anode and the tube flange. The sleeve has passages on its outside cylindrical surface and on the surface contacting the nozzle anode.

Abstract: A multiple-filler-material guide nozzle assembly for feeding multiple fusible filler metal wire or other metal forms into reduced-width, high-aspect-ratio (ratio of depth to width) metallic joints with control and stability of the filler metal position as it enters the molten pool area. The multiple filler materials are fed concurrently at the same or different feed rates. To control the aiming consistency for each of the multiple fillers even with substantial amounts of "cast" in the filler shape (after being unwound from a spool), the nozzle holes can be curved to match the curvature of the "cast" filler wire. This forces the curved filler wire to consistently follow the predetermined orientation of the curved shape of the nozzle. The multiple nozzles can be used to compensate for weld dilution effects by alloying to generate more favorable uniform, gradient or stepped compositions in joints or cladding.

Abstract: A TIG welding method is usually carried out in a manner that a tungsten electrode is inserted into a weld groove portion of a member to be welded, an electric voltage is applied to a current conducting portion provided for the tungsten electrode while flowing a shield gas means to thereby generate an arc between the tungsten electrode and the member to be welded to form a molten pool of the member, a welding wire is inserted into the molten pool, and a welding torch is then operated to perform a welding process. In the improvement of the TIG welding method, the shield gas means is composed of an inner shield gas flowing from a periphery of the tungsten electrode to a front end thereof inserted into the weld groove portion of the member to be welded and an outer shield gas flowing towards the weld groove angle from an outside of the inner shield gas to prevent the molten pool from being oxidized and to prevent oxygen in air from being involved.