Abstract: A plasma torch and method for cutting a workpiece under water directs a primary gas through a primary gas flow path in the torch to a central exit opening of the torch disposed on a longitudinal axis of the torch for exhaustion from the torch onto the workpiece in the form of an ionized plasma. The workpiece is submerged in water while the plasma torch is operated in closely spaced relationship with the workpiece to direct the ionized plasma upon the workpiece. A secondary gas flow path in the torch receives a secondary gas separate from the primary gas and directs it through the torch. Concentrically arranged first and second sets of secondary exit openings are disposed in the torch separate from the central exit opening and in generally radially spaced relationship with the longitudinal axis of the torch. The secondary exit openings exhaust secondary gas from the torch in a direction generally toward the workpiece.

Abstract: A torch head having a base section, a tip section and three or more radial rods connected between the base section and the tip section. The radial rods form a generally circular inner chamber which inner chamber includes an electrode. One or more of the radial rods has an inner passageway to convey one or more shielding gasses and/or one or more cooling fluids from the base section to the tip section of the torch head. The cooling fluid cools at least a portion of the torch head. The shielding gas is directed about the electrode and onto the weld metal to improve the quality of the weld bead. One or more of the radial rods function as support structures to enhance the strength and the rigidity of the torch head. The tip section of the torch head is designed to direct the one or more shielding gas in a desired profile about the electrode and onto the weld metal. The tip section includes an electrical contact that form an electrical connection with the electrode as the electrode passes through the tip section.

Abstract: Material droplet generator systems utilizing single-wire arc spray apparatus and methods are provided. In some embodiments, the apparatus include a single consumable, first wire electrode fed through a gas nozzle and a non-consumable, second electrode outside of and proximate a nozzle exit. In some embodiments, the second electrode may have at least a terminal or end portion having an axis that is oriented substantially perpendicular to an axis of the gas nozzle. The first wire electrode may form an angle of 5 degrees or less with the axis of the gas nozzle. Preferably, the first wire electrode forms an anode while the second electrode forms a cathode. In operation, apparatus and methods of the present invention produce a narrow beam thermal spray, which, when deposited upon a substrate surface, results in a high definition spray pattern and coating having distinct boundaries and a controllable thickness.

Abstract: The present invention relates to a strain relief mechanism for a plasma arc torch. In particular, the invention relates to a strain relief system including a positive axial restraint component for restraining axial movement of a lead relative to a housing and a positive rotational restraint component for restraining rotational movement of the lead relative to the housing, wherein the positive axial restraint component and the positive rotational restraint component are independent components arranged in a spaced relationship relative to each other.

Abstract: An apparatus (105) and method are provided for feeding wire (135) to a tip (120) of a torch (115) in a welding system(100). The apparatus (105) includes a drive mechanism (150) attached to the torch (115), and a guide assembly (155) attached to the drive mechanism. The guide assembly (155) includes a bracket (180) by which it is attached to the drive mechanism (150), a wire guide (185) through which the wire (135) is passed, and first and second adjustors (270A, 270B) to position the wire guide relative to the tip (120). The guide assembly (155) is configured to pass the wire (135) in a straight line from the drive mechanism (150) to the tip (120). In one embodiment, the adjustors (270A, 270B) include gimbals (275) supporting the wire guide (185). Each gimbal (275) is attached to a screw (280) passing through an opening in an arm (285) projecting from the bracket (180) of the guide assembly (155).

Abstract: The present invention provides a fixing structure for a welding electrode and a welding head which enable improvement of durability of a welding electrode, improvement of work efficiency in welding, and reduction of time required for welding and also which make it possible to execute welding for a long time with high reliability. In this fixing structure, a fixed section of a welding electrode is inserted via a thermally conductive material into an inserting section of a fixing base and a peripheral surface of the fixed section of the welding electrode is uniformly contacted to the fixing base to fix the welding electrode to the fixing base.

Abstract: A gas lens assembly for use in a gas shielded welding torch to provide laminar gas flow to the weld puddle. The assembly includes a plurality of annular fine mesh inner filter screens mounted in fixed axially spaced disposition in a gas chamber formed between the lens body and lens sleeve. The filter screens are preferably spaced apart a predetermined distance by a plurality of wave-shaped open mesh spacer discs disposed in a sandwich configuration between the filter screens. A stack of adjacently disposed outer filter screens are mounted in the gas chamber outwardly of the fine mesh filter screens. Each of the outer screens in the stack is individually removable such that the outermost screen can be readily peeled from the stack when damaged by spatter or heat to maintain the laminar gas flow through the assembly and prolong the useful life of the assembly.

Abstract: A plasma arc torch is disclosed which has an elongated electrode with an open front and a nozzle with a plasma discharge opening that is coaxial with the electrode. A mounting arrangement includes a ceramic ring that engages the front end of the electrode and a gas ring which concentrically surrounds the ceramic ring. A forward portion of the gas ring, the forward end of the electrode, and the nozzle define a swirl chamber of the torch, and opposing, spaced-apart concentric cylindrical surfaces of the ceramic ring and the gas ring, respectively, form an annulus which extends rearwardly from the swirl chamber. The ceramic ring closes the aft end of the annulus, and the gas ring houses a plurality of plasma gas injection ports which are located immediately forward of the aft end of the annulus.

Abstract: A contact start plasma torch and method of starting the torch includes a negatively charged cathode body and a positively charged anode body. A conductive element in the torch is constructed of an electrically conductive material and is free from fixed connection with the cathode body and the anode body. The torch is operable between an idle mode wherein the conductive element provides an electrically conductive path between the cathode body and the anode body and an pilot mode wherein a pilot arc is formed between the conductive element and at least one of the cathode body and the anode body. The pilot arc is blown by working gas flowing through the torch toward an exit orifice of the torch whereby 10) the working gas is exhausted from the torch in the form of an ionized plasma.

Abstract: A hot wire welding method and system rely upon a welding torch with a non-melting electrode, a melting metal filler wire that is fed into a weld puddle created by welding arc, a microprocessor controller for controlling (i) current of the main welding arc, (ii) filler wire feed speed, and (iii) hot wire current for heating the filler wire. The method and system also rely upon a main welding power supply for supplying the main welding arc and a secondary DC supply for supplying the hot wire current. The hot wire current is automatically controlled by the microprocessor to supply the correct amount of current to the filler wire in response to changes in wire feed speed.

Abstract: A hot wire welding method and system includes a welding torch with a non-melting electrode, a melting metal filler wire fed into the weld puddle created by the welding arc, a microprocessor controller for controlling the current of the main welding arc, filler wire feed speed, and hot wire current control for the heating of the hot wire. The method and system also includes a main welding power supply for supplying the main welding arc and a secondary DC supply for supplying the hot wire current. The hot wire current is automatically controlled by the microprocessor to supply the correct amount of hot wire current to the filler wire with changes in wire feed speed.

Abstract: An electrode for a plasma arc torch and method of fabricating the same are disclosed, and wherein the electrode comprises a copper holder defining a cavity in a forward end. An emissive element and separator assembly is positioned in the cavity, and no brazing materials are used to secure the components of the electrode. An intermetallic compound is formed between the emissive element and the separator, and a eutectic alloy is formed between the separator and metallic holder by independent heating steps. A crimping process is also disclosed for further strengthening the electrode and increasing the operational life span thereof.

Abstract: An electrode for a plasma arc torch and method of fabricating the same are disclosed, and wherein the electrode comprises a copper holder defining a cavity in a forward end. An emissive element and separator assembly is positioned in the cavity. The emissive element is formed from the powders of at least two materials, and the separator includes a material that is substantially similar to one of the materials forming the emissive element. The emissive element is heated and a plurality of thermal conductive paths are formed that extend from within the emissive element to the separator that improve the thermal conductivity of the electrode.

Abstract: A device with a plasma torch with a rod-shaped non-consumable electrode which is held in a receiver, is connected with an electric connection and penetrates a nozzle which is in connection with a gas connection. In order to also enable the rapid and secure welding of difficult alloys it is provided that a further rod-shaped non-consumable electrode is disposed in the receiver which is made from an electrically non-conducting material, which further electrode also penetrates a nozzle which is in connection with a gas connection, with the two electrodes enclosing an acute angle and each being in connection with a separate voltage source supplying direct voltage pulses, the level of which exceeds at least the arc voltage of an arc between one of the electrodes and a counterelectrode which is associated with the same and connected with the same voltage source.

Abstract: A method of welding a plurality of connection ends of a plurality of copper segments forming a circumferentially disposed stator winding of a rotary electric machine. The method includes a step of inserting a protection member between connection ends of adjacent two of the plurality of copper segments, a step of activating a welder tool, and a step of circumferentially moving the welder tool relative to the connection ends.

Abstract: An insulative grip for a TIG torch is held in a person's fingers like a pen or pencil. The grip has an external contour that has multiple gripping areas. The size and shape of the gripping areas conform to the person's thumb and first two fingers when he holds the grip. The gripping areas reduce the tendency for the torch to move in the person's hand. The gripping areas also provide an indication of the orientation in space of the torch electrode when the person holds the torch. The torch may be either water-cooled or air-cooled.

Abstract: A plasma arc torch and method are provided for directing a flow of gas substantially the length of an electrode before splitting the gas into a primary flow and a secondary flow. The torch includes an electrode having a metallic holder defining a plurality of openings at a forward end for directing all of the gas therethrough and into a chamber defined by the holder and a nozzle. The nozzle defines a central bore and a plurality of secondary openings for splitting the gas in the nozzle chamber into at least the primary flow and the secondary flow.

Abstract: Stainless steels are welded using a shielding gas including 88 to 98.9 mole % Ar, 1 to 10 mole % H2, and 0.1 to 2.0 mole % CO2. The shielding gas permits low sulfur, high chromium, austenitic stainless steel pipes to be joined with welds having sufficient penetration, strength, corrosion resistance and durability for practical use.

Abstract: A heating apparatus and method for pre-weld heat treating, welding and post-weld heat treating a superalloy article in a single enclosure while avoiding oxidation of the article. The enclosure is preferably equipped with a one-way valve that permits the escape of gases, but otherwise seals the enclosure to prevent the ingress of air during welding and heat treatment as a result of thermal gradients induced when the article is inductively heated. To provide access to the article and a device used to weld the article, the enclosure is equipped with gloves by which the welding device and the article can be manipulated while a nonreactive atmosphere is fully maintained within the enclosure and the article is inductively heating.

Abstract: A Multi-Electrode Welding System for performing high-precision welding and joining is disclosed. One embodiment of the invention comprises a sealed chamber (13) which is enclosed by a weld head frame (11), a removable lid (12) and a chamber base (14). A generally tubular workpiece (not shown) is placed in a pair of semi-annular inserts (16) and extends into the sealed chamber (13), which is filled with an inert gas. In one embodiment, a weld head rotor (18) revolves around the longitudinal axis defined by the workpiece, and controls the motion of an inside electrode (24A) and an outside electrode (24B), which are held by inside and outside electrode holders (20 & 22). Arc welding is performed by the electrodes (24A & 24B) as they revolve around the workpiece. Inside and outside welding may be performed simultaneously. The invention provides for precise control of the relative position of the electrodes, allowing one electrode to trail the other.

Abstract: A plasma arc torch and method for cutting a workpiece in which the torch has a primary gas flow path for receiving a primary working gas and directing it through the torch to a central exit opening of the torch for exhaustion from the torch onto the workpiece in the form of an ionized plasma. A secondary gas flow path in the torch receives a secondary gas separate from the primary working gas and directs it through the torch. The primary gas flow path is in fluid communication with the secondary gas flow path substantially upstream of the central exit opening of the torch to bleed primary working gas in the primary gas flow path into the secondary gas flow path for admixture therewith to form a secondary gas mixture to be exhausted from the torch.

Abstract: The invention relates to a blow torch (6) for a cutting process, in particular a steam cutting process, comprising a control device (3), a liquid supply system, in particular a container (5) for a liquid (8), and a power source (2), the blow torch (6) being connected via lines (9, 10) to the power source (2). The blow torch (6) is connected by a supply line (7) to the liquid supply system. At least one duct or flow passage for the liquid (8) having a predeterminable cross section and path is provided in the blow torch (6) and is designed to convert the liquid (8) into a gaseous state, in particular a gas (19).

Abstract: The object is to facilitate replacement of consumable parts, such as the electrode, nozzle, or the like, in a plasma torch, whilst suppressing any increase in structural complexity or cost. An electrode 103, insulating guide 105 and nozzle 107 are fit together installed in a retainer cap 113. By means of O-rings 193, 195, 197, the electrode 103, insulating guide 105, nozzle 107 and retainer cap 113 are coupled together by a coupling force which allows the components to be pulled apart and separated manually. By attaching the retainer cap 113 to the torch main unit and detaching the retainer cap 113 from same, the electrode 103, insulating guide 105 and nozzle 107 can be attached and detached to and from the torch main unit, simultaneously.

Abstract: The process for the TIG alternating-current welding of aluminum using an inert-gas mixture of helium and argon uses an inert-gas mixture of 83 to 95% by volume of helium, the remainder being predominantly argon.

Abstract: A plasma arc torch and method for cutting a workpiece in which the torch has a primary gas flow path for receiving a primary working gas and directing it through the torch to a central exit opening of the torch for exhaustion from the torch onto the workpiece in the form of an ionized plasma. A secondary gas flow path in the torch receives a secondary gas separate from the primary working gas and directs it through the torch. The primary gas flow path is in fluid communication with the secondary gas flow path substantially upstream of the central exit opening of the torch to bleed primary working gas in the primary gas flow path into the secondary gas flow path for admixture therewith to form a secondary gas mixture to be exhausted from the torch.

Abstract: A heating apparatus and method for pre-weld heat treating, welding and post-weld heat treating a superalloy article in a single enclosure while avoiding oxidation of the article. The enclosure is preferably equipped with a one-way valve that permits the escape of gases, but otherwise seals the enclosure to prevent the ingress of air during welding and heat treatment as a result of thermal gradients induced when the article is inductively heated. To provide access to the article and a device used to weld the article, the enclosure is equipped with gloves by which the welding device and the article can be manipulated while a nonreactive atmosphere is fully maintained within the enclosure and the article is inductively heating.

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 potentiometer located toward the rear portion of the torch. If a rotary potentiometer is used, the torch diameter here 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. If a linear potentiometer is used, the body may be maintained very slim over its entire length. Weld disturbance due to torch movement during current adjustment is virtually eliminated by use of the fingertip operated rotary control.

Abstract: First and second sub-parts are brought into contact with each other so as to form an unwelded hollow structure defining an internal volume. The internal volume of the hollow structure is inerted by introducing an inerting gas mixture into the hollow structure, the inerting gas mixture comprising from 93% to 99.8% nitrogen and from 0.2% to 7% oxygen and being produced by air permeation by means of one or more membrane modules. The first and second sub-parts are arc welded together so as to form a welded hollow structure.

Abstract: A diffuser assembly is provided for narrow groove welding using an automatic gas tungsten arc welding torch. The diffuser assembly includes a manifold adapted for adjustable mounting on the welding torch which is received in a central opening in the manifold. Laterally extending manifold sections communicate with a shield gas inlet such that shield gas supplied to the inlet passes to gas passages of the manifold sections. First and second tapered diffusers are respectively connected to the manifold sections in fluid communication with the gas passages thereof. The diffusers extend downwardly along the torch electrode on opposite sides thereof so as to release shield gas along the length of the electrode and at the distal tip of the electrode. The diffusers are of a transverse width which is on the order of the thickness of the electrode so that the diffusers can, in use, be inserted into a narrow welding groove before and after the electrode in the direction of the weld operation.

Abstract: An object is to provide a plasma torch having a function to achieve fully satisfactory cooling of the nozzle and shield cap. A plasma torch 1 comprises a nozzle 17 positioned at the front end portion of the torch 1 so as to cover an electrode 13, with a plasma gas passage 37 interposed therebetween. A shield cap 21 is mounted at the front end of the nozzle 17, and these components 13, 17 and 21 are accommodated in a retainer cap 23. Assist gas passages 45, 55 are formed in the wall of the retainer cap 23, and feed assist gas to the vicinity of the plasma arc 81. A space enclosed by the retainer cap 23, nozzle 17 and shield cap 21 is a cooling water passage 63. The retainer cap 23, nozzle 17 and shield cap 21 faces the cooling water passage 63, and hence directly and powerfully water-cooled.

Abstract: An electrode body (3) for a plasma torch comprises at least one tapping (15) within which is provided at least one recess (8) extending over all the lengths (d) of the tapping (15), and at least one downstream portion defining a recess (16) located between the upstream tapped portion and the bottom of the electrode body (3)

Abstract: The invention relates to a protective gas for TIG welding of metals, especially high alloy or low alloy steel, whose thermal conductivity is lower than that of aluminium. The inventive gas consists of argon, helium and hydrogen and enables significant improvements to be made in electric arc stability, welding speed, oxidation of weld surface and adjacent area, flow-on performance and weld appearance.

Abstract: A plasma welding torch comprises a non-consumable electrode arranged in a chamber provided in the torch and having a free flat end face extending substantially perpendicularly to a longitudinal axis of the electrode and having a diameter of 15% to 35% of the maximum diameter of the electrode. An inlet port leads to the chamber for delivering a plasma gas thereto, and an outlet port leads from the chamber to an orifice at an outer end of the outlet port, the outlet port having an interior wall, the electrode having a free tapering end section reaching at least to the outer end of the outlet port, and the interior wall of the outlet port being spaced from, and surrounding, the free tapering end section of the electrode and extending to the orifice substantially parallel to the tapering end section of the electrode.

Abstract: A pad piece is unitedly formed on a wrapping terminal to be contacted by an electrode probe and positioned to be opposed to a welding torch, and the electrode probe is held by the welding torch to approach a wrapping terminal, whereby the electrode probe held by the welding torch is automatically brought into contact with the pad piece of the wrapping terminal as the welding torch approaches the wrapping terminal to complete potential fixing.

Abstract: A method of centering an electrode in the nozzle of a plasma arc torch head is disclosed. The method involves complementing the external wall of the swirl to the internal taper of the nozzle; complementing the internal wall of the swirl to the external taper of the electrode; fitting the hollow tapered swirl so formed in the hollow nozzle to abut the inner taper of the nozzle; and fitting the electrode in the hollow swirl to abut the inner taper of the swirl to center the electrode within the nozzle. Also disclosed is a head for a plasma arc cutting torch which includes a a swirl located between the nozzle and the electrode, through which plasma fuel gas is introduced into the nozzle, characterized in that the plasma fuel gas is introduced directly into the plasma formation zone or plenum beyond the junction between the nozzle body and cone end thereby avoiding change in direction within the conical end of the nozzle before the plasma formation zone.

Abstract: Two parts are welded together at a weld spot in a groove. A spot adjacent the weld spot is heated simultaneously and independently of the welding so that the heating and welding form a heat-treated weld bead along the groove. Preheat treatment, postheat treatment, or both, may be used simultaneously with welding to maximize performance of the resulting weld joint. Preheat and postheat treatment may be performed using lasers while the welding may be performed by TIG welding or laser welding. The welding torch and preheat and postheat lasers are coplanarly aligned.

Abstract: An improved method for welding and passivation forms a chromium oxide passivated film over the welded portion during the welding process. In a shielding step, a backshield gas, preferably argon, is flowed around the welding site. In a welding step, an arc gas, preferably argon with approximately 10% hydrogen and less than 1 ppm moisture content, is flowed through the welding head and a welded joint is formed, for example by high speed tungsten-inert gas (TIG) orbital welding. In the passivation step, a process gas, preferably argon with approximately 30-100 ppm of oxygen and less than 1 ppm moisture content, and preferably less than 1 ppb moisture content, is flowed over the welded portion to form a chromium oxide passivated film on the welded portion. The process gas is passed through a gas purifier prior to being flowed over the welded portion to maintain its moisture level at less than 1 ppb.

Abstract: Male/female assembly for a plasma torch comprising: a nozzle (1) forming a male portion, a nozzle carrier (2) forming the female portion to receive said nozzle (1), characterized in that the nozzle (1) comprises, on its external periphery, at least one helicoidal ramp (14) and at least one recess (15) extending over all the axial length (L) of the ramp, and in that the nozzle carrier (2) comprises, on its internal peripheral surface, at least one projection (21) adapted to coact with at least one helicoidal ramp (14) of the nozzle (1), so as to be able to ensure holding the nozzle (1) in position in the nozzle carrier (2).

Abstract: A plasma arc torch has a cathode and electrode having connecting ends configured for a coaxial telescoping connection with one another on a central longitudinal axis of the torch. The connecting ends have interengageable detents thereon, with at least one of the detents being movable in a generally radial direction relative to the central longitudinal axis of the torch between an undeflected state and a deflected state. The at least one detent is movable from the undeflected state to the deflected state when the cathode and electrode are telescoped one into the other, and is movable from the deflected state back toward the undeflected state when the cathode and electrode are further telescoped tc, a point where the detents on the cathode and electrode are generally axially aligned. In this position, the at least one detent is engageable with the other detent to interconnect the cathode and electrode and inhibit axial movement of the electrode away from the cathode.

Abstract: In a method for plasma-arc welding of metals with a direct or indirect arc, used as a plasma-producing medium is the vapor of a water-containing fluid doped with an organic solvent appearing as oxygen-containing hydrocarbon compounds, in particular, alcohols, and vapors are generated immediately in the plasma-arc torch.

Abstract: Male/female assembly (11) for a plasma torch comprising an electrode body (3) and an electrode carrier (4), in which:the electrode body (3) comprises at least one tapping (15) within which is provided at least one recess (8) extending over all the lengths (d) of said tapping (15), and at least one downstream portion defining a recess (16) located between the upstream tapped portion and the bottom of the electrode body (3), andthe electrode carrier (4) comprises, on its external peripheral surface, at least one gauge (4") having at least locally a profile corresponding to the profile of said at least one recess (8) of the electrode body (3) and at least one screw thread (15'), said gauge (4") being located between the downstream end of the electrode carrier (4) and said screw thread (15).

Abstract: The invention relates to an electric arc welding torch comprising a torch body having an electrode holder (3) and a nozzle (4), said nozzle (4) being formed with at least one nozzle partition (2) having an internal surface (2a) and an external surface (2b), characterized in that at least one supplemental partition (8) extends along at least one portion of the internal surface (2a) and/or external surface (2b) of the nozzle partition (2), in that one of said partitions (2, 8) is electrically conductive and in that the other of said partitions (2, 8) is electrically insulating and the use of such a torch in an electric arc welding or cutting process under a protective gas, particularly a TIG, MIG or MAG welding process.

Abstract: An electrode for use in a plasma arc torch has an insert designed to improve the service life of the electrode, particularly for high current processes. The electrode comprises an elongated electrode body formed of a high thermal conductivity material and having a bore disposed in a bottom end of the electrode body. The bore can be cylindrical or ring-shaped. An insert comprising a high thermionic emissivity material, and in some embodiments, a high thermal conductivity material, is disposed in the bore. The insert can be ringed-shaped or cylindrical.

Abstract: The filler wire in hot wire-gas tungsten arc welding (HW-GTAW) apparatus is heated to near the melting point by application of the hot wire current over a determined length sufficient that the current required is low enough to avoid significant arc blow. This predetermined length of filler wire which approaches the molten state is supported by a ceramic sleeve which in turn may be protected by a stainless steel sheath.

Abstract: The present invention relates to ignition circuitry for a plasma generator. A discharge is created by application of a high frequency or high voltage dc ignition pulse between an electrode and a first nozzle. Following ignition, the discharge is redirected to a second nozzle for the purpose of moving the plasma flow from the ignition zone into the zone of application to the workpiece. The present invention is directed to plasma ignition circuitry for improving this performance. Positive thermal coefficient ("PTC") resistance is shown to be useful in reliably and reproducibly switching the arc. Alternative embodiments of the present invention relate to switching the plasma from a first nozzle to a second nozzle then sequentially to additional nozzles downstream in the flow of plasma gas in which PTC resistance is used to reliably and reproducibly effect the switching.

Abstract: A plasma burner is provided which includes a combustion chamber, in which an arc is generated between an adjustable anode and a fixed cathode. An operating gas is supplied to the combustion chamber for plasma formation. A positioning device enables the anode and the cathode to be positioned relative to one another and fixed.

Abstract: A flow of ionizable gas is provided to a shielded plasma arc torch which includes an electrode, a translatable nozzle, a nozzle retainer, and a shield. After passing through a heat exchanger to cool the electrode, the gas flow enters an annular chamber where the flow is divided into three subflows. A first subflow enters a plasma chamber formed by the electrode, the nozzle, and a swirl ring to pressurize the plasma chamber and support a plasma arc. The second subflow passes serially through apertures in the nozzle retainer and the shield to shield the plasma arc. The remaining flow is vented to ambient. Accordingly, a single gas flow may be employed to independently support multiple torch operating requirements.

Abstract: The invention relates to a plasma torch in which the position of the electrode (4) with respect to the orifice (11) of the plasma nozzle (5) can be adjusted. The electrode (4) is mounted on the body (3) of the torch via a ball-and-socket joint (14), whereby the electrode (4) can be rotated supported by the joint (14) thus facilitating the alignment of its tip in the center of the orifice (11) of the plasma nozzle (5). The ball part (14) of the joint is clamped in the socket (15) by means of a tightening bushing (16). The plasma torch electrode (4) is fixed to the pivotal joint (14) by way of a longitudinally adjustable assembly (12, 17, 20, 25), whereby the tip of the electrode (4) can be moved with the help of the adjustment assembly (12, 17, 20, 25) to touch the nozzle (5) thus effecting the alignment of the electrode in the pivotal support of the ball-and-socket joint (14) and under the guidance of the sliding tip of the electrode (4) to the center of the nozzle orifice (11).

Abstract: The invention relates, on the one hand, to an electric-arc work process, such as a plasma cutting or TIG welding process, in which a torch is supplied with at least one non-oxidizing gas, the said torch being provided with at least one electrode made of pure or alloyed metal, such as a tungsten electrode, characterized in that the said non-oxidizing gas contains a concentration of impurities of the oxygen type [O.sub.2 ] of less than 80 ppmv and a concentration of impurities of the water vapor type [H.sub.2 O] of less than 400 ppmv and, on the other hand, to such a welding gas.

Abstract: A dual flow nozzle shield of a plasma-arc torch positioned in front of a torch end cap and secured in such position by a shield retaining cap. The shield is made from lava or wonderstone ceramics or copper materials. The shield has three support feet for resting on a counterbore section of one end of the cylindrical torch end cap and for providing space between the shield and the shield retaining cap for gas bypass around the outside of the shield. An alternate embodiment of the nozzle shield comprises a plurality of notches around the perimeter of the shield for the bypass gas to pass through. A primary gas enters the shield with a portion of the primary gas going through an orifice in the center of the shield. Both embodiments have a backflow or bypass portion of the primary gas that does not go through the orifice, but instead goes back up and through the space between the posts in one embodiment or the notches in the second embodiment and comes down over the outer side of the shield.