Abstract: A method and apparatus for reducing "arc blow" in multi-electrode welding of a metallic workpiece. Arc blow is produced by interaction between the magnetic fields produced by the closely spaced arcs and electrodes, and takes the form of the end arcs being attracted inwardly towards the others. This reduces the welding efficiency and the maximum welding speed. The invention reduces or eliminates the arc blow by providing shunts made of magnetically permeable material close to the arc-producing ends of the electrodes at the two ends of the row of electrodes. This reduces the concentration of magnetic flux in these regions and reduces the deviation of the end arcs. The invention can be applied wherever multi-electrode welding is used, but is especially useful when the workpiece is made of aluminum as arc blow is a particular problem with this metal.

Abstract: A method and an apparatus for welding an impeller by using TIG process are provided in which one of the blades to be welded to a side plate or shroud plate is disposed so as to form a V-channel with the plate, the V-channel being oriented to face upwardly, and a torch head supported at the tip of a torch rod is placed above a weld line produced by the intersection of the blade and the plate so as to contact the inner surface of the V-channel keeping a proper distance between the tip of the tungsten electrode encased within the torch head and the weld line on which a filler wire of suitable length is disposed.

Abstract: A method of improving the reproducibility of the welds in an electric spot welding machine comprises prior to the initiation of a welding operation passing a preheating current of lower magnitude than the welding current through the parts to be welded. When either the total electrical workpiece resistance of the parts to be welded has fallen below a given limit or when its rate of decrease is slower than a predetermined limit the changeover from preheating current to welding current is effected.

Abstract: Disclosed is a method of plasma treatment of materials comprising introducing a plasma-forming mixture including carbon-containing compounds chosen from the class of hydrocarbons or carbon monoxide into the space between the electrodes of an electric arc device to provide deposition of carbon at least on one of the electrodes of an electric arc device in the course of arc burning, striking an electric arc, and introducing an oxidizing agent into said space between the electrodes to improve the stability of arc burning, the oxidizing agent being introduced into said space between the electrodes over a time interval between the instant when a heat flow into the electrode whereon carbon is deposited reaches its maximum value and the instant when said heat flow drops down to a steady value.

Abstract: An electro-slag welding method using as a consumable electrode a strip of mild steel and an electric insulating material. The steel strip has a width substantially equal to the thickness of the plate material to be welded. The electric insulating material is composed of a slag-forming agent, a deoxidizing agent and an alloying agent and is disposed between the steel strip and the material to be welded, and also between the strip and shoe, if necessary.The electric insulating material used in the welding method is provided in the form of two plates disposed on opposite sides of the steel strip, or in a hollow rectangular form to enclose the steel strip.The electric insulating material is molded from powdered slag-forming agent, deoxidizing agent and alloying agent with a net of a mild steel material, which is used as core.

Abstract: A weld and process for making same and usable in the arc-welding of cupro-nickel (ASME P.34) parts particularly pipe ends using a flux-coated stick electrode, characterized in that an "open V" butt weld is employed with a root face having a mean width greater than 1/16 inch (1.5 mm) and not greater than 1/8 inch (3.2 mm) and a root gap from 2 to 3 mm. The process is further characterized in that the welding is carried out solely from the open side of the V without employing additional inert gas shielding, backing material or subsequent welding at the reverse face.

Abstract: A method of consumable electrode arc welding with the end of the electrode submerged into the molten pool wherein the maximum cross sectional dimension of the electrode end to be submerged into the molten pool is chosen so that it does not exceed twice the minimum dimension of this cross-section. Said dimensions are made to fit the required width of the weld by adopting the minimum dimension of said cross-section of less than the width but no less than half the width, for the same weld width required. The arc length is set below said minimum dimension, and the consumable electrode is fed at a speed lower than the welding speed, choosing the ratio of the consumable electrode feed speed to the welding speed, for the same weld width required, so that the greater the cross-sectional area of said end of the consumable electrode, the smaller is the ratio.

Abstract: A method and a device for adaptive control of the weld parameters in automatic arc welding processes to weld together two workpieces. The arc is arranged to oscillate in the transverse direction of the groove and by measuring the welding current and/or welding voltage on two separate occasions during the deposition of the root run characteristic values are obtained. The values obtained on these two occasions are combined mathematically with a calculated rated value. This rated value corresponds to the height of the root bead of the weld. The discrepancy of the obtained values from the calculated rated value is used to control means arranged to set the weld parameters, thus ensuring that a homogeneous weld is obtained, irrespective of groove variations, such as variations in the gap width between the two workpieces, or variations of other factors affecting the weld.

Abstract: A method of welding the ends of submerged pipes in a gaseous atmosphere at any depth comprises isolating the ends of the pipes by introducing obturators therein and then introducing the pipe ends into an open topped receptacle which is capped with an underwater personal carrying intervention unit. The closed receptacle is filled with gas and then a sleeve is positioned between the ends of the pipes and welded to the pipes.

Abstract: A process for improving the mechanical properties of welded silicon steel. The weld heat affected area of welded silicon steel is heat treated while retaining the welded lengths within a clamping fixture so as to restrain movement thereof from the initiation of welding through the completion of the heat treatment.

Abstract: For welding rotor blades to a rotor disc of a rotary machine, a welding process is used wherein grooves, called blind slots, are formed through the disc wall thickness but not to the extent to pass through the entire thickness, whereafter the blades are basted by a Tungsten Inert Gas run without added welded material, the blind slots being then filled up by a series of Tungsten Inert Gas welding passes but with added weld material. Headroom limitations are offset and the weld seams come out more robust and with a better surface quality.

Abstract: A spindle for an axle is capable of supporting a vehicle wheel which is rotatably mounted thereon. The method for forming such a spindle includes providing a hollow tubular blank having a generally uniform external diameter and wall thickness and forming the blank to generally reduce its diameter to thereby provide a pair of axially separated wheel bearing mounting regions for supporting the vehicle wheel. A portion of the blank inwardly of the inner bearing region is provided a frusto-conical outer surface. A collar having an inner surface to match the taper of the frusto-conical surface is installed thereon for providing an axial stop for the adjacent bearing. Several alternative methods are provided for securing the collar thereon.

Abstract: In an automatic arc welding method for welding metallic materials having a vertically curved weld line, a change in the arc voltage is compared with a arc length setting voltage and the resulting difference signal is used to control the vertical position of a welding torch and hold the same at a predetermined distance from the materials to be welded, while on the other hand in response to a signal generated from an obliquity detector made integral with the torch, the torch is controlled at an angle corresponding to the oblique angle of the materials to be welded and at the same time the welding speed is controlled at a constant value in response to a signal corresponding to the torch angle.

Abstract: A method and apparatus for welding or brazing of sheetmetal or plate covered with a temperature degradable protective coat, such as zinc or plastic. A cooling saddle supplied with liquid nitrogen is arranged on the side of the plate opposite that adjacent the welding torch. During the formation of the weld, gaseous nitrogen escapes through holes in the saddle to cool the protective coat and keep it from melting or volatilizing.

Abstract: The invention concerns a process for the final assembly of a nuclear reactor vessel comprising two sub-assemblies which are brought together and welded along mating surfaces. At least three female centering stubs, each associated with a seat recessed relative to the outer surface of the stub, are provided on the mating surface of one of the sub-assemblies, and at least three male centering stubs, corresponding to the seats of the female stubs, are provided on the mating surface of the other sub-assembly, the positions of the stubs being registered relative to elements for positioning internal fitments of the vessel. The two sub-assemblies are brought together to engage the male stubs in the female stub seats and to bring projecting annular ridges on the mating surfaces into contact. A key is inserted into a socket defined by one of the pairs of stubs and the stubs are then joined to each other by point-welds.

Abstract: A unitary welded connection between a projecting leg of a cell connecting strap and collector tabs emanating from the plates of the cell is disclosed, the leg having boss protrusion(s) to eliminate bridge welds.

Abstract: A process for balancing a crankshaft having pin portions and associated balancing weight parts which counterbalance the pin parts comprising welding masses to the balancing weight parts to compensate for unbalance of the crankshaft. The welding takes place after the crankshaft has been heat treated. The weld masses are directly formed on opposite sides of peripheral surfaces of the balancing weight parts without any preliminary formation of grooves in the peripheral surfaces for the weld masses.

Abstract: A method for cutting by a plasma arc in which the nozzle is directly contacted with the base metal to be cut and is at the same electrical potential, and wherein the electrode is first approached near to the base metal to strike the arc and then withdrawn from it to an appropriate cutting distance, and which permits a thinner cutting line to be made and thinner materials to be cut.

Abstract: In welding or working operations using an electric arc a nitrogen compound is introduced into the working or welding area for the purpose of decomposing ozone in said area. The nitrogen compound is preferably purely nitric oxide, but may also be nitrous oxide (N.sub.2 O) or ammonia (NH.sub.3).

Abstract: A method is provided of vertical gas metal-arc two-sided welding of thick plate in a single welding pass on each surface of the plate. The method includes providing a first weld groove on one surface of the plate into which a weld bead is deposited in a single pass. Thereafter, a second weld groove is formed on the opposite surface of the plates by removing base plate material along the joining line to a depth extending at least to the first weld bead penetrating from the welding pass in the first weld groove. The plates are further joined together by depositing a weld bead in a single pass along the second welding groove. The welding is provided by impressing a direct electric current of from 290 to 420 amperes between an electrode and the plates shielded primarily by argon gas.A metal article and a welded joint are also provided.

Abstract: Workpieces, such as structural steel, are cut under water by a plasma burner having a needle electrode with the plasma arc slightly under the water level and the plasma arc being enveloped during the ignition and cutting by a compressed air sheath outside the nozzle which strongly contracts the plasma cutting arc.

Abstract: A method of welding utilizing consumable and non-consumable electrodes blanketed with inert gas to weld with a minimal amount or no preheating.

Abstract: During arc welding, optical radiation emitted from an arc is detected by means of a photoelectric device, and an electric detection signal from the photoelectric device is used for controlling the travel of a suction hood along a weld line so that the weld fumes may be exhausted through the suction hood and to insure that the weld metal zone is always covered by the suction hood.

Abstract: Welding methods and apparatus, wherein a welding electrode is oscillated by a motor-driven oscillator in back and forth movements transverse to a weld joint, and an alternating welding current is supplied to the welding electrode in timed relation with the welding tip oscillations so that weld metal is deposited along opposite sides of the weld joint in parallel paths without deposit of weld metal at the center of the weld joint.

Abstract: A welding apparatus including a nozzle assembly having a contact extension and a contact tip for guiding a consumable welding wire into a tube hole. The consumable welding wire is guided into the tube hole and an electric current is passed to the wire to produce an arc between the tip of the wire and the sidewall of the tube hole, melting the wire and supplying filler weld to the hole. The nozzle assembly has a gas nozzle; and, during the welding process, an inert gas is delivered into the tube hole through the gas nozzle.

Abstract: The invention relates to a plasma cutting plant comprising a principal generator feeding a plasma arc between a workpiece and an electrode of a torch comprising a tube, with initial ignition by means of an ignition or striking arc between the electrode and the tube, via the resistor and the contactor. A circuit comprising a resistor and an excitation coil of a relay is installed across the terminals of the contactor. When the torch has been brought to the correct distance from the workpiece, the circuit detects this correct spacing and acts on the feed motor to stop the latter immediately.

Abstract: A method for manufacturing a gas turbine combustion chamber that preserves cooling fluid holes therein. Passages are formed in one surface of each of two metal sheets. A plurality of cooling fluid holes are drilled through the passages to the other surface of each sheet. The two metal sheets are abutted face-to-face so that their respective passages form channels and the sheets are thereafter brazed together. The brazed sheets are bent to form an annular shaped chamber having a butt joint running along the length of the chamber. The butt joint is electric-arc welded along each side of the same, there being only partial penetration by each weld thereby avoiding the filling in of any of the cooling fluid holes, in the line of the weld, with melted material.

Abstract: Large metal structures for heavy duty machines are prefabricated from subassemblies. The subassemblies are made with matched grooves, and held together. The subassemblies are machined taken apart transported to the field reassembled and electroslag welded in the area of the grooves.

Abstract: A method of controlling the synchronized movement of a backing shoe in an automatic one-side welding of the type in which a light-transmittable backing material is placed in close contact with the back surface of the welding joint and a backing shoe adapted to be moved along with the movement of a welding apparatus is pressed through the backing material against the back surface of the welding joint just below a welding electrode whereby effecting the welding. The method employs photoelectric detectors which are embedded in the surface of the backing shoe contacting the backing material at four positions, i.e.

Abstract: A contoured welding rod forms a stringer bead to couple the adjacent bevelled end surfaces of an aligned pair of metal pipes or metal sheets. The welding rod is fabricated from an uncoated alloy metal and has an upper section which includes symmetrical side surfaces inclined at an angle equal to the angle of inclination of the bevelled end surfaces of the pipes or sheets. The rod also includes a lower section which is coupled to the lower portion of the upper section and is dimensioned to penetrate through the gap between the adjacent bevelled end surfaces of the pipes or sheets. During the welding operation the upper section of the rod joins the bevelled surfaces of the pipes or sheets, while the lower section of the rod joins the surfaces of the pipes or sheets on the opposite side of the gap between the pipes or sheets.

Abstract: One metallic plate is set upright on another metallic plate and a filler fills each corner formed of both plates. A deposit metal is deposited on and adjacent to each filler to weld the plates to form a recess on that portion to the deposit metal facing a non-welded portion located between the welded plates. Alternatively the recess may be formed by supplying an inert gas to a space formed between the two plates and simultaneously depositing a deposit metal on the plates across the space.

Abstract: Disclosed herein is an improvement of a welding process for welding a steel pipe, wherein a gas metal arc welding is performed to form the first welding layer and a submerged arc welding is performed to form the last welding layer. According to the conventional gas metal arc welding process, i.e. the MIG or CO.sub.2 welding processes, the combined use of a high welding current and a welding wire having a small diameter is known to bring about the rotation of the welding arc and the formation of an undercut along the toe of the weld metal. The purpose of the present invention is to weld a steel pipe having either a large thickness or an excellent ductility at a temperature of less than -40.degree. C., or both. According to the present invention, the combined use of a high welding current and a wire having a small diameter is possible, by employing a gas mixture containing an inert gas as a major part thereof and CO.sub.2 as an additional part thereof as a shielding gas.

Abstract: The specification discloses a method and apparatus for assuring the integrity of outside weldings of pipelines. Pipe sections are prepared for welding by forming a beveled profile with a relatively narrow annular contact band on the ends of each pipe section. When the pipe sections are abutted end to end for welding, the leveled profiles form a relatively deep groove on the outside of the pipe between the pipe sections, with the annular contact bands abutting and spaced inwardly from the grooves. The contact band on at least one of the pipe sections is circumferentially prepared such as by knurling to provide controlled spacing between the contact bands of the pipe sections. A welding arc is applied to the bottom of the groove from the exterior of the pipe sections to weld the annular contact bands together. Welding penetration is enhanced by the circumferential preparation of the contact bands.

Abstract: A narrow weld-groove welding process, in which a bare welding wire is fed into a weld groove defined between the opposed surfaces of two pieces of metals for producing a metal arc therein for welding. In this process, a welding wire is subjected to a plastic deformation of a wave form, before being fed into a nozzle hole provided in a contact tip, and then the wire is fed into a nozzle hole, while maintaining elasticity tending to cause waving, whereby the tip of a welding wire being fed through a nozzle exit is automatically waved between the opposed surfaces of metals to be joined, with the tip of wire being alternately faced in the opposite directions, in response to the weaving motion thereof, with the feeding of the welding wire and progress of welding. In addition, the apparatus for use in a narrow weld-groove welding process is also disclosed.

Abstract: A process for adjusting a welding torch with respect to a weld joint formed between two workpieces is disclosed, including determining operating quantities for arcs located in at least two positions relative to said weld joint, deriving characteristic values for each of those operating quantities, mathematically combining such characteristic values, and comparing the mathematical combination with a theoretically calculated value for such characteristic values, and then adjusting the position of the welding torch in accordance with the difference between the mathematical combination of those characteristic values and their theoretically calculated value.

Abstract: Relates to a flux dam for submerged arc vertical position welding. The dam comprises a sheet of high temperature stable non-metallic material, a permanent magnet aligned with a first pole thereof substantially at a first surface of the sheet for magnetically attaching the sheet to a vertical workpiece generally parallel to and spaced by the thickness of the workpiece from a generally horizontal weld area of the vertical workpiece to an abutting horizontal workpiece, the magnet extending generally towards a second surface of the sheet, the magnet being affixed in the aforementioned alignment thereof. Also relates to an improvement in a welding method using said dam.

Abstract: An apparatus for arc welding of a pair of spaced steel plates from one side only using a grooved back-up plate which gives a good weld bead shape on the under side, gives high linear welding speeds, and avoids contamination of the deposited weld metal by the metal from the back-up plate. A pair of consumable electrodes connected in electrical series between the output terminals of the power source and with one connected by an independent connection to the workpiece are advanced into the weld gap on lines of movement which intersect at a point above the lower surfaces of the plates so that an arc is maintained between the electrodes spaced from the base of the back-up plate groove. A separately energized electrode trails the first two electrodes and deposits a weld bead on the first deposited weld metal while it is still hot.

Abstract: Apparatus for automatically welding a plug which is previously driven into holding engagement with the tube sheet to plug a leaky tube which has been reamed out to produce a pressed fit with the plug.

Abstract: A groove is provided on the side of a metallic structure opposite to the side thereof which is exposed to a corrosive atmosphere, and the groove is subjected to build-up welding while cooling with a liquid coolant, whereby any stress corrosion cracking which otherwise occurs on the side of the structure to be exposed to the corrosive atmosphere can be prevented. Especially, this method of manufacture is appropriate for the repair welding of a butt-welded pipe of austenite type stainless steel, and it is effective to perfectly prevent the stress corrosion cracking of the pipe prone to be caused by reactor water during use in a nuclear reactor.

Abstract: Plasma-MIG welding in which a thermally ionizable gas stream is flowed through a nozzle non-consumable electrode having a central orifice and a surrounding annular opening toward a workpiece and is thereby split into a central gas column enveloped by an annular gas shield. A consumable electrode is fed through the central gas column toward the workpiece, with the establishment of a MIG-arc therebetween. A plasma arc is then spontaneously established by means of the MIG-arc between the nozzle non-consumable electrode and the workpiece. The central plasma gas column is accelerated by constriction of the annular gas shield downstream of the nozzle non-consumable electrode.

Abstract: Disclosed is a method of reinforcing an aluminium alloy piston ring groove wherein the piston body is fused to a certain depth around the periphery thereof in the zone where the ring groove is to be cut, with simultaneous introduction of an alloying addition into the fused aluminium alloy of the piston body, thus forming an annular wear-resistant weld therein, whereupon the ring groove is cut in the periphery of said weld.

Abstract: A process for implanting a precise quantity of radioactive metal on a metal substrate such as a cutting tool or other metal part subject to wear at the area or areas where the part is expected to wear during its operation. The presence of the radioactive spot can be sensed to determine the extent of wear during use. The radioactive metal is deposited from a wire formed of a core of the radioactive metal surrounded by a sheath of metal having a high thermal and electrical conductivity relative to the core. In operation, the wire contacts the metal surface under pressure and electric current is passed through the wire in order to (1) form a pit on the tool surface, (2) weld the radioactive metal in the pit and (3) evaporate a small portion of the conductive sheath adjacent the pit. A second current then is passed through the wire to break it near the bottom of the pit, leaving a small quantity of radioactive material welded to the bottom of the pit.

Abstract: The corrugation is removed from an end portion of a helically corrugated tube, and an internally threaded sleeve is threaded onto the tube. The sleeve has an unthreaded extension which is being drawn by a suitable tool to engage the smooth wall portion of the tube and is subsequently welded thereto.

Abstract: A method and apparatus for lowering the contrast range between a welding arc and its surroundings for remote viewing of an arc welding process. A monochromatic light source (10) is used to illuminate the area surrounding the welding arc (18) and a narrow band interference filter (22) tuned to the wavelength of the monochromatic light (10), is placed in front of a viewing camera (24). The monochromatic light enhances the arc background while the filter (22) attenuates the arc illumination that reaches the camera for a more desirable contrast ratio so that the arc, weld puddle and surrounding area can be visible with a high degree of definition on the monitor.

Abstract: Non-continuous forms are welded on an automatic device using a continuous welding process (e.g., Tungsten Inert Gas Process (TIG) with a continuous welding arc. The noise level of the welding system is below that which is prescribed by the Operational Safety and Health Act (OSHA). The device includes apparatus for indexing and positioning the non-continuous forms relative to the welding electrode. The device further includes apparatus for chilling the non-continuous forms during the welding process, and apparatus for periodically shunting the welding arc away from the non-continuous forms so as to maintain a continuous welding arc.

Abstract: A plasma-MIG welding system includes establishing a plasma arc between a primary non-consumable electrode and an auxiliary non-consumable nozzle electrode to provide a plasma flow downstream of the primary non-consumable electrode and out through such nozzle electrode. A consumable electrode is fed through the plasma flow out through the nozzle electrode, a MIG-arc being established between the consumable electrode and a workpiece. A gas stream consisting of an inert gas and an oxidizing gas is flowed past the consumable electrode in a manner to completely envelope the same and into admixture with the plasma flow without coming into contact with the non-consumable electrode. A separate gas stream provides a sheath for the resulting plasma flow after its passage through the nozzle electrode.

Abstract: A method of connecting metallic parts, and metallic parts so produced, by means of arc fusion welding by producing a low volume welding seam (narrow gap welding), wherein the workpiece parts to be jointed and forming a narrow gap are initially welded at their butt joint by means of, for instance, electron-beam welding, plasma-arc welding, laser-beam welding or argon arc-welding to produce a base seam with or without filler material, and thereafter the workpiece flanks forming the narrow gap are united by alternately depositing weld beads at first one and the other workpiece flank by submerged-arc welding.

Abstract: A submerged arc welding method and more specifically, a multiple electrode welding method is disclosed wherein welding is performed by arranging electrodes in such a manner that the distance becomes at least 300 mm between a first molten pool formed by multilayer welding or by a single or plural electrodes preceding along the weld line and a subsequent molten pool formed by a single subsequent electrode or plural subsequent electrodes, as well as a submerged arc welding method which is characterized in that there is formed a slag having the components listed below on the weld metal formed by an electrode or a preceding electrode forming a preceding layer, and welding is carried out as such, without removing the slag, using an electrode or a subsequent electrode forming a subsequent layer;TiO.sub.2 : 20-65% by weight (up to 60% by weight, based on the total TiO.sub.2 amount, of which may be substituted by ZrO.sub.2);CaF.sub.2 : 9.6-40% by weight, andAl.sub.2 O.sub.3 : 10-56% by weight.

Abstract: A method for butt welding pipe sections together wherein each pipe section has a beveled end includes positioning the pipe sections adjacent one another so that the beveled ends define a weld groove and locating filler material of elongate dimension having a triangular cross-section so that an edge portion thereof protrudes through the weld groove. The filler material is fused to the weld groove by striking an inert gas-shielded arc between a Heliarc torch electrode and the beveled ends and advancing the electrode relative to the filler material so that a weld bead is formed having a convex profile on the interior surfaces of the pipe sections adjacent the weld groove.

Abstract: A method of treating electrodes intended for operation in argon as electric arc cathodes. Each of the electrodes being treated consists of a holder with an active insert. The active insert comprises elements selected from the series of rare-earth elements, yttrium, alkali-earth elements, elements of Group IV A of the periodic system and compounds thereof, taken separately or in combination. The electrodes are treated in an electric arc burning in an atmosphere of argon and an active gas, such as nitrogen or oxygen. During the course of treatment the electrode functions as a cathode. A mixture of argon and oxygen or argon and nitrogen is fed to the cathode area of the arc. The duration of the electrode treatment cycle is at least 100 times less than that of the electrode operation time in an argon arc. Treatment is conducted by currents that do not exceed the maximum operating current values of the treated electrode. The volume concentration of the active gas in the mixture varies from 0.1 to 100%.