Abstract: In a welding gun apparatus, an improved welding gun quick connector assembly in which supply conduits may be quickly and easily connected and disconnected from a connector body. Supply conduits are securely retained by circumferentially overlapping flanges fastened down with a screw threadably adapted to a passage in the connector body. A seal intermediate between supply conduits and connector body is provided to prevent fluid and gas leakage.

Abstract: An improved system (50) for shielding a circumferential region about elongate workpieces from air contamination during welding or heat treatment includes a pair of generally cylindrical shields (52, 54) which define central openings for receiving the workpieces, and which are positioned in longitudinally spaced apart relationship about the joint or region to be welded or heat treated. The shields (52, 54) are of symmetrical but otherwise identical construction. For example, the shield (52) includes a first annular chamber (70) and associated annular diffuser positioned adjacent the process zone, and a second annular chamber (86) and associated cylindrical diffuser (90) extending away from the zone. The chambers (70, 86) are connected to independent sources of inert gas, which flows both into and out away from the process zone to eliminate air contamination from aspiration and the like.

Abstract: An improved welding method for welding an inner seam of a longitudinally welded steel pipe along an inner groove by welding electrodes held by a boom which is supported by a tracing roller moving along the inner groove of the steel pipe. According to the invention, at least one metal plate is urged against at least one end of the steel pipe after tack welding the seam on an opposite side of the inner groove of the steel pipe to be welded. Lateral angular deformations of the end of the steel pipe are prevented on both sides of the seam. Such deformations are due to the load of the boom when the tracing roller leaves the end of the steel pipe for the metal plate. Thus, the invention provides for prevention of hot cracking at the end of the pipe.

Abstract: A process for producing an ERW tube having welds which have been improved in toughness without adversely affecting the toughness of the parent metal of the tube is disclosed. The process comprises forming a continuous low alloy steel strip into a tubular shape through a series of forming rolls, continuously carrying out electrical resistance welding of a seam which is formed from the opposite side edges of the hoop and which extends in the longitudinal direction to produce an electrical resistance welded tube, heating the welds of the thus obtained electrical seam welded tube to a temperature not lower than the A.sub.c3 point, then cooling the heated welds at cooling rate of 15.degree.-30.degree. C./sec for at least between 800.degree. C. and the A.sub.r1 point, and tempering the thus cooled welds of the tube at a temperature of 450.degree.-800.degree. C.

Abstract: A welding device which provides a sort of a template function for guiding the electrode and tig torch of a gas tungsten arc welding procedure, the device providing a smooth and conical guide surface for the template-effect of an adjustable-radius guide surface, each circular portion of which is concentric about the axis (axes) of the tube(s) to be welded.

Abstract: A welding electrode is provided which is suitable for welding chromium containing ferritic corrosion resistant steels. The electrode comprises a low-carbon manganese steel core wire having a carbon content of less than 0.1% by mass, and a manganese content of 0.35-0.60% by mass. The electrode has a basic chromium alloyed flux coating, which upon welding, deposits a low-carbon chromium martensitic ferritic weld metal comprising about 90% by mass low carbon martensite and about 10% by mass ferrite and having a carbon content of less than 0.04% by mass.

Abstract: A scissors-type electric welding apparatus is provided which has a transformer, a pair of electrodes, a pair of first arms movably mounted on the transformer, an electrically insulated articulation shaft, and a pneumatic jack. A pair of second arms are pivotably connected to the articulation shaft. The second arms support the electrodes on one end and are connected to the jack on the other end in order to move the electrodes apart to position the electrodes for welding workpieces. The electrodes are electrically connected to the first arms through the second arms. Each second arm includes a contact member mounted on the articulation shaft. Each first arm includes a free end which carries a contact shoe for interacting with a contact member. A biasing member is provided for urging the contact shoes against the contact members.

Abstract: The pressure-differential method for sleeve-to-tube joining comprises inserting a sleeve within a tube and joining the sleeve to the tube. An internal heating device is then inserted into the sleeve for bonding the sleeve to the tube. The portion of the sleeve to be joined is then sealed so that the portion of the sleeve to be joined may be internally pressurized. Once the sleeve has been so pressurized, the heating operation may be begun. In the case of welding, as the welding progresses the molten weld pool under the arc is continuously driven by the internal pressure gradient toward the external tube. In this manner the arc force is cushioned by the molten pool at all times thus preventing the weld arc from piercing through the sleeve. In the case of brazing, as the heating progresses the sleeve becomes more pliable such that the internal pressure causes the sleeve and braze material to closely contact the inner surface of the tube.

Abstract: A composite electrode configuration prevents mushrooming of resistance spot welding electrodes due to local high contact pressure and current densities. For a truncated electrode, an outer sleeve of high strength and high electrical resistivity material is attached to the end of the electrode and takes the high contact stress at the edge of the flat end face. A spherical end electrode has a plug of higher strength material in the center where the highest contact stress exists, and the outer sleeve reduces the joule heating effect. A transverse insulating spacer is a thermal and electrical barrier.

Abstract: A welding apparatus for internally welding sleeves to tubes comprises a central shaft with an electrode attached thereto which are capable of being inserted in a tubular member. A plurality of remotely actuable seals are disposed on the welding apparatus and around the electrode for establishing a sealed chamber in the sleeve in which the welding may take place. The welding apparatus is capable of supplying an inert shielding gas to the sealed chamber for pressurizing the sealed chamber during the welding process and while the electrode completes a weld around the inner circumference of the sleeve. The apparatus may also be used to internally braze the sleeve to the tube.

Abstract: A method of pool-slag welding is carried out in the well-known manner and arrangement, however, with determined altering current intensity and/or voltage. A control unit is used which is suitable for the pulsewise altering of the values of current intensity and/or voltage which are necessary for welding. Altering current intensity is carried out advantageously by regulating the speed of feeding of the welding filler wire. The method and apparatus makes the production of intermittent welds possible, which are of better quality, greater toughness and better impact strength than the welds produced by known methods and apparatus.

Abstract: In a resistance welding apparatus of a detachable grip type an improvement consists in that each pipe grip has a bracket (16) whereon two double-arm levers (18), one per side member (3), are pivoted. Similar arms of each lever (18) are interconnected by an extension spring (19), while the other arms are operatively associated with swinging jaws (14) adapted to abut against the pipe surface in their operating position. Each side member (3) is provided with a stop (21) for limiting the movement of the levers (18) relative the corresponding side member (3) in the direction of the action of the extension spring (19).

Abstract: A torch for gas-shielded arc welding in a deep narrow groove comprises a current contact torch bit (1) with an electrode (2) and a nozzle for supplying the shielding gas to the welding zone, which communicates with a gas-feeding tube (4) and is provided with at least one row of horizontally arranged holes (5). The nozzle is a closed chamber (3) made as a symmetrical wedge whose sharp edge faces the electrode (2) and is in one plane with the axis thereof. The side walls and bottom of the chamber (3) feature at least one additional row of holes (6) whose axes lie in one plane approximately perpendicular to the walls (7) of the groove.The torch is designed primarily for welding of very thick workpieces.

Abstract: Ground metallic adding material is fed into the welding gap. Electrodes are introduced into the gap in pairs, one electrode in a pair opposite the other, at an angle equal to the angle of divergence of the end faces being welded together. The electrodes are positioned so that their larger faces are parallel with the end faces being welded together and the smaller faces extend beyond the side surface of the workpiece being welded.

Abstract: In an apparatus and a method of at least partially suppressing oxidation of can components or the like during resistance roller welding with the aid of an inert gas, the steps include welding the can components to one another, so as to obtain a hot welding seam, supplying the inert gas to the hot welding seam so as to envelop it at least partially, and to create a region of the inert gas in contact with the surrounding atmosphere, so that oxidation of the hot welding seam is at least partially suppressed.

Abstract: A method and apparatus for collecting molten metal and/or slag together with fume generated by the air carbon-arc cutting and gouging process. The method and apparatus are characterized in that a refrigerated surface is used to intercept and cool the molten particles to prevent adherence of the particles to the collector or agglomeration of the particles inside the collector.

Abstract: A pistol grip brazing tool utilizes an insulative frame to mount a pair of elongated support elements, one fixed and the other reciprocating. The support elements, in turn, mount at their front ends a pair of electrodes in opposed relation and at their rear ends brazing cable connectors. Conductive links affixed to the support elements are adapted with interconnecting conductive cable lengths such as to conduct brazing current between the electrodes and the cable connectors in shunt relation with the support elements. The flow of brazing current is controlled to insure that brazing operations are performed without undue arcing.

Abstract: An apparatus for spot arc welding overlapping pieces in which a pair of contact electrodes with concave portions are arranged opposite to each other, and at least one electrode has a central hole to accommodate a consumable electrode; the concave portions are shaped to correspond to the calculated shape of the reinforcements at both sides of the spot welded joint.

Abstract: A carbon rod assembly is disclosed which includes a first carbon rod piece having a projection at one end thereof and a second carbon rod piece having a socket hole at one end thereof. External and internal screw threads of 1/2 to 3 turns are formed on the projection and socket hole respectively, so that the first and second carbon rod pieces are firmly connected by inserting the projection into the socket hole and thereafter rotating the carbon rod pieces relative to each other.

Abstract: An apparatus for gas-shielded arc welding comprises a mechanism (1) for guiding and feeding an electrode to a welding zone (3), a nozzle (4) for feeding a protective gas medium to the welding zone (3) and a TV transmission camera (6) for realtime monitoring of the welding process. A cover plate (8) made of an optically transparent material is provided at the end (7) of the gas nozzle (4) which is remote from the welding zone (3), and a lens (9) of the TV camera (6) is installed above the cover plate (8) coaxially therewith. The distance ("a") from the cover plate (8) to the lens (9) is selected in such a manner that the zone (3) of sharpness of the lens is located beyond the edge (11) of the gas nozzle (4) which is adjacent to the welding zone (10) and extends over the components of the welding process.An apparatus for gas-shielded arc welding is designed preferably for welding thick plate materials, for example, pressure vessel casings.