Abstract: A method for detecting a surface welding quality of friction stir welding includes: acquiring a continuous surface depth image of a welding seam; intercepting a surface depth image segment of the welding seam with a proper step size, and dividing the intercepted surface depth image segments of the welding seam into a front reference region, a thinned region and a rear reference region; judging whether flatness of the front reference region is less than a threshold, and if yes, taking a height of the front reference region at this point as a latest reference height; if no, judging whether the flatness of the rear reference region is less than the threshold, and if yes, taking a height of the rear reference region at this point as the latest reference height; if no, taking the reference height of previous depth image segment as the latest reference height; and calculating a difference.

Abstract: A system for heating a selected section of a conductive ribbon comprises a non-conductive base and conducting pads. Further, the system comprises a variable voltage power supply electrically coupled to the conducting pads and a sensor. A processor is programmed to enable the variable power supply to produce a voltage signal across the conducting pads to cause the selected section, which includes a biological sample and is clamped to the non-conductive base via the conducting pads, to heat up. The processor receives, from the sensor, an electrical measurement. A correction for the voltage signal is computed based on the measurement to achieve a desired temperature, wherein the desired temperature is for processing the biological sample and the correction accounts for a variance in the selected section. The applied voltage signal is adjusted based upon the correction to regulate the selected section of at the desired temperature for a time.

Abstract: A clamp system and method for measurement and control of welding a first substrate to a second substrate is provided. The system comprises a squeeze clamp having to a first end and a second end. The system further comprises a motor connected to the squeeze clamp such that the first and second ends are movable to clamp the first substrate to the second substrate. The system further comprises at least one of an electromagnetic flux sensor, a current sensor, a position sensor, and a gap sensor disposed on one of the first and second ends for determining a first measured variable between the first and second substrates. The system further comprises a controller to control the motor to clamp the first substrate to the second substrate based on the first measured variable. The controller is in communication with the electromagnetic flux sensor, the current sensor, and the gap sensor.

Abstract: This welding method is a flash butt welding method of a pair of track rail steel pieces, having: a preheating process in which electric current is made to flow for a predetermined time in a state in which the welding surfaces of a pair of track rail steel pieces are forcibly brought into contact with each other, and vicinities of the welding surfaces are heated by resistance heating; a former flashing process in which flashing is partially caused in the welding surfaces, and the welding surfaces are heated by the resistance heating and arc heating of the flashing; and a latter flashing process in which the flashing is furthermore caused throughout the entire welding surfaces, and the entire welding surfaces are uniformly heated by the resistance heating and arc heating of the flashing, in which a latter flashing velocity is 2.1 mm/sec to 2.8 mm/sec in the latter flashing process.

Abstract: The invention relates to a welding head for a welding device for welding components which are not rotationally symmetrical onto workpieces such as for example metal sheets, with a head attachment, the head attachment having a holding device for the component and being designed for carrying a welding current to the component, wherein the holding device is mechanically connected by means of a connecting device to an interface device, via which the welding current can be supplied, the connecting device being subdivided into a first connection piece and a second connection piece, which are electrically insulated from each other.

Abstract: The continuous rolling method and the continuous rolling apparatus provide good product quality and product yield by successively joining pluralities of traveling hot steel pieces by flash welding, and by rolling thus prepared endless steel piece, thus preventing generation of flaws in the rolling step, thereby manufacture steel rods, wires, and the like by the continuous rolling technology. The method has: a heating step for heating billet to a specified temperature; a flash welding step for joining the trailing end of preceding billet with the leading end of succeeding billet while they are traveling using flash welding; a deburring step for removing burrs from the welded part; a trimming step for trimming corners of cross section of the deburred welded part; and a rolling step for rolling the joined billets.

Abstract: In a force freeze welding method and system for joining metal work pieces, a controlled and programmable electrical potential is applied to a circuit including a first work piece (130) and a second work piece (140). The first work piece (130) is linearly translated towards the second static work piece (140) to engage along a faying interface (190). The first work piece (130) and the second work piece (140) move together at a controlled rate and voltage is applied to the circuit which produces heat to soften or plasticize the faying interface (190) during a flashing stage (310). A position offset (210) or abrupt compression force is applied to at least one of the first work piece (130) and the second work piece (140) prior to applying an upset (330) to force the first work piece (130) and the second work piece (140) together to weld the first work piece (130) and the second work piece (140) along the faying interface (190).

Abstract: A method and apparatus for detecting a joint between workpieces is provided. At least one light line is recorded by the light section method to detect the three-dimensional course of the joint and a grey-level image of the joint is also recorded. The grey-level image is evaluated to assess the quality of the joint.

Abstract: A resistance butt flash welding machine comprises two work piece clamping platens, at least one of which is movable with respect to the other, an electric servo motor operatively mechanically connected to the movable platen, and a programmable electrical control connected to the servo motor to control the motor, and programmed to regulate the pattern of timing of changes in motion of the movable platen, to control speed of the motion and to control the upsetting force applied to the movable platen required to forge together work pieces clamped in the platens. The process of use of the machine includes programming the programmable control.

Abstract: A resistance butt flash welding machine comprises two work piece clamping platens, at least one of which is movable with respect to the other, an electric servo motor operatively mechanically connected to the movable platen, and a programmable electrical control connected to the servo motor to control the motor, and programmed to regulate the pattern of timing of changes in motion of the movable platen, to control speed of the motion and to control the upsetting force applied to the movable platen required to forge together work pieces clamped in the platens. The process of use of the machine includes programming the programmable control.

Abstract: A process for the acquisition of data in the form of measurements and calculations, for diagnosis and decision assistance for an electric direct spark butt welder and for the resulting weld seams comprises the respective steps of measurement of the instantaneous alternating voltage at the terminals of the primary (19, 33) and of the secondary (16, 35, 36) of the welder transformer, and between the jaws (18, 39) of the welder dies; measurement of the instantaneous current in the primary (24, 34) and the secondary (17, 37, 38) of the transformer; measurement of the instantaneous displacement (41, 42) of the mobile die (4); storage in memory of said voltages, said currents and said displacement during the welding process; calculations of the energy supplied by the primary and the secondary, preferably to the jaws (5, 6), as a function of time; calculation of the energy supplied by the secondary to the jaws and of the heat energy dissipated during sparking as a function of the displacement of the mobile die; calc

Abstract: The invention concerns a method for controlling the butt welding, by flash welding, of two metallic parts (A, A′) in a welding machine of the type comprising two pairs of clamping dies (2, 2′) mounted respectively on a fixed frame (1) and on a mobile frame (1′) for contacting rear (3) and front (3′) ends of both parts (A, A′) and the flow of an electric welding current.

Abstract: The invention relates to an installation for welding metal bands comprising two retaining members (2, 2′) for the ends of both bands, mounted respectively on a fixed frame (1) and a mobile frame (1′), means for shearing both facing parallel edges (m1, m2) on the ends of both bands (M1, M2) and electric power supply means (3) for flash butt welding of the said bands. According to the invention, the electric power supply means of both bands comprise a direct current generator (3) connected to continuous modulation means (34) of the voltage applied between the retaining members (2, 2′) in relation to the sizes of the bands (M1, M2) in transversal section and according to the nature of the metals to be welded.

Abstract: The invention relates to a machine for butting two metal bands (M1, M2) and a method for implementing such a machine.

Abstract: A flash-butt welder having a stationary head 41 and a moving head 42, a pair of electrodes 45a, 45b, and 46a, 46b coupled to each of the stationary and moving heads, respectively, power source transformers 12 through 16 are located at the stationary head 41 side. Four bus bars 21 through 24 connecting the power source transformers 12 through 16 with the electrodes 45a, 45b, 46a, and 46b are arranged at symmetrical positions surrounding a billet 10. However, the number of bus bars, 22 and 24, which are connected to the electrodes 46a and 46b at the moving head 42 side is half the total number of four bus bars.

Abstract: A method and apparatus are provided for flash butt weld joining adjacent rail ends on site during initial field installation where at least one of the rails is fastened to the roadbed, and inclosure butt welding rails as in de-stressing long sections of rail track where both rails are fastened to the roadbed. The method and apparatus apply electrical power to the adjacent rail ends while simultaneously effecting relative closing movement between the rails ends through actuating means so as to bring the rail ends into position to effect current flow between the rail ends, and determining a force necessary to move the adjacent ends into a welding position under varying environmental conditions of the rails as the adjacent rail ends close and during flashing of the adjacent rail ends due to the current flow.

Abstract: A flash-butt welder having a stationary head 41 and a moving head 42, a pair of electrodes 45a, 45b, and 46a, 46b arranged to each of the stationary and moving heads, respectively, wherein power source transformers 12 through 16 are located at the stationary head 41 side, four bus bars 21 through 24 connecting the power source transformers 12 through 16 with the electrodes 45a, 45, 46a, and 46b are arranged at symmetrical positions surrounding a billet 10, while the bus bars, 22 and 24 as half of the number are connected to the electrodes 46a and 46b at the moving head 42 side.

Abstract: A system for automatically feeding studs to the electrode of a manual stud welding tool. The system comprises a magazine associated with the tool. The magazine receives a tandem row of studs mounted in and collated by a disposable mounting and collating strip assembly. A drive assembly is associated with the magazine to advance the mounting and collating strip assembly such that each stud, when it becomes the forwardmost stud of the tandem row, is properly positioned with respect to the tool to be welded to a workpiece.

Abstract: A machine for flash-butt welding of rails, incorporates two tong-type clamping devices made in the form of two two-arm levers carried by a common central axle with insulation from each other and capable of being displaced along the axle relative to each other by two flashing-upsetting hydraulic cylinders connecting them and having bimetal current-carrying rods. Each of the two-arm levers is hinged at one end to the rod or the clamping hydraulic cylinder case, respectively, and the other end is fitted with the clamping and current-carrying jaws. Two welding transformers built into the hollow two-arm levers of one of the two tong-type clamps are joined by current-carrying jumpers through the current-carrying part of the rods of the flashing-upsetting hydraulic cylinders to the current-carrying clamping jaws. A clamping hydraulic cylinder is made with a hydraulic intensifier built into its rod.

Abstract: An apparatus for joining billets in continuous rolling mill comprises a pair of parallel rails 14, a travelling welding machine 4 having first support rolls 54,55, a travelling grinding machine 5 having second support rolls 56a, 56b,57, a first group of carriages 41,42,43 each of which has a third support roll 51,52,53 for supporting billets, and a second group of carriages 44,45,46 each of which has a fourth support roll 58,59,60 for supporting billets. The travelling welding machine welds a rear end of a preceding billet with a front end of a succeeding billet while moving on the pair of rails. The travelling grinding machine removes burrs on a weld zone of the billets while moving on the pair of rails. The first group of carriages is arranged upstream of the travelling welding machine and is connected with the travelling welding machine by a flexible joint member.

Abstract: A flash welding machine is capable of cutting ends of a pair of preceding and following weld members 1, 2 by means of a shear device 26, 27 and then flash welding them with each other. The flash welding machine can coat an appropriate amount of combustible fluid on the cut end surfaces of the weld members 1, 2. When a first end sensor 31 and a second end sensor 31 sense widthwise leading ends of the weld members 1, 2, a first and a second nozzle 35, 36 start coating the combustible fluid on the cut end surfaces of the weld members 1, 2 from the widthwise leading ends of the weld meets 1, 2. The nozzles 35, 36 stop coating when either one of the sensors 31, 33 senses a widthwise trailing end of one of the weld members 1, 2. Thus, it becomes possible to coat the combustible fluid on the cut ends of the weld members 1, 2 over an area extending from the widthwise leading end to the widthwise trailing end thereof.

Abstract: A flash butt welding facility exhibits a housing (1) and a slide (2) linearly displaceable in the former. Respectively one clamping system is installed in the housing (1) and in the slide (2), by means of which profiled workpieces, e.g. rails (5a, 5b), can be retained and positioned. A device for displacing the clamping systems, especially for compressing profiled workpieces (e.g. rails), comprises at least one press cylinder (11) arranged above the workpiece clamping axis (17) and acting in the longitudinal direction and at least one lever (8) rotatably connected to the slide (2) in the force application point (9). The press cylinder (11) is connected to one end of the lever (8). The center of the lever (8) is articulated (7a) to the housing by way of a pull rod (6a). The pressing force produced above the rail clamping axis (17) is made to be effective in the clamping axis in this way.

Abstract: Techniques for assuring the accuracy of the welding of a part including a part calibration cycle, a tap check cycle and a gap detection cycle. The part calibration cycle determines the electrical load presented by the part to the welder transformer. The tap check cycle verifies that the operator has set the correct tap on the primary of the welder transformer, The gap detection cycle finds the actual spacing between the platen when the ends of the part are substantially touching so that the ends of the part can be accurately spaced at the beginning of the weld cycle.

Abstract: A mobile electric flash-butt welding unit for welding together adjacent ends of track rail sections comprises a pair of welding heads displaceable in a longitudinal direction towards each other, each welding head comprising two tong-like parts pivotal towards each other and carrying clamping electrodes for engaging the sides of a respective one of the rail section ends. Actuating cylinders extend in the longitudinal direction and are connected to each welding head for pressing the welding heads in the longitudinal direction towards each other, and clamps are connected to each welding head and are spaced in the longitudinal direction from the actuating cylinders connected thereto, each clamp comprising jaws for gripping the sides of the respective rail section end therebetween.

Abstract: A process and apparatus for leak-proof sealing of a metallic capsule closed by a stopper and joining the capsule to a metal cable by arc welding, wherein a capacitor is charged, the capsule with a striking tip at one end or the stopper with an ignition point and the cable are clamped at their ends, connected to the terminals of the capacitor, moved together and welded together by discharging of the capacitor with the formation of an arc.

Abstract: The machine incorporates two clamping means, a static one fitted to a bedframe and a movable one mounted on rods which are attached to upsetting hydraulic cylinders with their ends with provision for reciprocating back and forth. Each clamping means consists of a base and a holding-down plate which is hinged to the base and displaced by a hydraulic cylinder a body of which is hinged to the base and a piston rod of which is hinged to the holding-down plate interacting with a holding down roller in clamping workpieces. The machine is provided with a fastener in the form of an inverted L-shaped lever, a means of adjusting the alignment of the workpieces for welding, and a means of setting a gap between the workpieces, made as a plunger and an adjustable stop installed coaxially.

Abstract: Apparatus for electrical flash butt welding the ends of metal sheet or strip including a pair of flat faced parallel welding electrodes extending across the full width of the metal sheet or strip, one on each side thereof, and an electrode cleaning device comprising a support assembly having mounted thereon an extendable electrode cleaning means including a cleaning head having a plurality of upward extending cleaning members and a plurality of downwardly extending cleaning members the cleaning head adapted to simultaneously remove dirt and contaminants from the contact surfaces of opposed welding electrodes.

Abstract: An apparatus for tensioning or longitudinally sliding a rail of a laid track to reduce a gap between adjacent ends of longitudinally successive rail sections to be welded together to form the rail, the fastening elements of the longitudinally successive rail sections having been loosened, which comprises a closed, ring-shaped mechanical structural unit including two longitudinally spaced pairs of rail clamping jaws and two transversely spaced hydraulic cylinder-piston devices connecting the pairs of rail clamping jaws and operating the same. These pairs of rail clamping jaws are spaced longitudinally and the cylinder-piston devices are spaced transversely to define a sufficient central space in the ring-shaped mechanical structural unit for receiving a flash-butt welding head.

Abstract: A mobile electric flash-butt welding machine comprises machine frame, undercarriages supporting the machine frame on a railroad track, and a drive for propelling the machine frame along the track. The machine frame carries a hydraulic fluid supply pump, an electric current generator, a motor for operating the pump and the generator, a longitudinally, transversely and vertically adjustable electric flash-butt welding head for selectively welding together the adjacent rail section ends of a respective one of the track rails, the welding head comprising two welding halves movable towards and away from each other in a direction of the rail, hydraulic cylinders for moving the two welding head halves in said direction, a pair of clamping and welding jaws on each welding head half, and a hydraulic clamping cylinder connecting the jaws of each pair.

Abstract: Disclosed is a machine for flash butt welding of pipes located in the bore of the pipes welded together, a housing (2) whereof is provided with rigidly attached thereto a first supporting disc (3) and a second supporting disc (4) and with a pipe flashing-and-upsetting means (5) which has a carrier (7) and a hydraulic actuator (6) for displacing said means along the housing (2) and also has two pipe clamping means (9, 10) each whereof is provided with a carrier (12 and 13) and self-contained hydraulic actuators (11) imparting axial motion to this clamping means.

Abstract: The disclosed process includes the steps of and upsetting the flashing parts being welded. The flashing is conducted with concurrent measurement of useful electric power and an electric parameter of the flashing process which is related to the power by a function which maximizes the useful power at a predetermined value of said electric parameter. Then the value and sign of the power and parameter increments are determined within one and the same period of time. The parts are brought closer together up to the moment when the ratio of the power and parameter increments reverses ints sign. Then the parts begin to be separated up to the moment when the value of said ratio reaches the preset value selected to suit the welding circuit resistance and the cross sectional area of the welded parts.

Abstract: In an apparatus for the butt welding of hollow molding of aluminum with two contact clamps (4, 5), movable toward each other, for the ends of the moldings to be joined together, one contact clamp (4) is fixed at the machine frame, and the other contact clamp (5) is arranged on a table (3) supported at the machine frame (18) by way of two parallelogram guide arm pairs (19, 20). Trough-like recesses (15) are provided in the mutually opposing end faces of the contact clamps (4, 5), a conduit for the feeding of protective gas during the welding operation terminating in the zone between the contact clamps (4, 5).

Abstract: There is proposed a control device for a flash-butt resistance welding mane, which comprises a welding transformer (1) whose primary winding is in series with a welding current pickup (7) connected to an electrohydraulic drive (30) of the moving electrode of the machine via a drive control unit (12). Said drive control unit (12) comprises two input amplifiers (14) and (15), first inputs thereof being coupled with the output of the welding current pickup (7), while second inputs of the amplifier (14) and (15) are coupled to a control voltage source (13). The output of each input amplifier (14) and (15) is connected, via transistor (21) or (22) and a voltage divider, to the input of an operational amplifier (29) whose output is connected to the input of the electrohydraulic drive (30), a welding voltage stabilizing unit being inserted into the primary circuit of the welding transformer (1), the control input of said stabilizing unit (6) being connected to the secondary winding of the welding transformer (1).

Abstract: Flash-butt welder in which the piston rod of a pneumatic cylinder is connected to one end of a pivotable lever arm. A pneumatic system sequentially supplies air at two different pressures to the cylinder. Fixed and movable platens, each with a work piece clamping jaw, are fitted onto a unitary shaft which is mounted in laterally spaced and generally parallel relationship with the pneumatic cylinder. The movable platen is moved by the opposite end of the lever arm along the shaft toward the fixed platen. The movable platen includes a laterally extending arm portion for angular orientation of the platen on the shaft. A switch is disposed to be actuated by the lever arm as it advances to a predetermined position which energizes a solenoid valve to supply substantially higher pressure air to the cylinder. An hydraulic cylinder, disposed in spaced parallel relation to the shaft, includes a piston rod engaged with a pivotable linkage carried by the arm portion of the movable platen.

Abstract: A welding apparatus for welding a trailing end of a preceding strip and a leading end of a subsequent strip including a shear device for cutting them in parallel and a back bar device for supporting the ends of the strips. Provision is made to detachably connect the shear device and the back bar device and move them along a common rail between the strip ends.

Abstract: A welding fixture by which two elongate members are manipulated in a manner to become butt welded together. Two gripping members in the form of groups of spaced slip assemblies are enclosed in mounted relationship within a housing. The slips of each group circumferentially extend about a longitudinal axis of the housing, with the slips of each group being radially spaced from the longitudinal axis of the members to be joined. A first group of slips are mounted for movement within a plane which is perpendicular to the longitudinal axis of the members to be joined. The other group of slips are likewise arranged within a plane spaced from and parallel to the first plane. All of the slips are moved with great force towards the longitudinal axis of the members to be joined. The fixture includes means by which the members are moved toward one another with great force. Each group of slips further include an electrical contact which provides a source of current to each of the members to be joined.

Abstract: A method and apparatus for flash welding are disclosed wherein a first predetermined voltage is applied between a pair of workpieces to be welded to generate flashes therebetween, and a second predetermined voltage lower than the first predetermined voltage is then applied between the workpieces to maintain fine flashes when the temperature of weld surfaces of the workpieces has reached a predetermined temperature. The workpieces are upset when the total number of flashes has reached a predetermined value. The pressure welding is maintained with an upsetting pressure sufficient to upset the workpieces and slightly higher than a pressure at which the workpieces are deformed near their recrystallization temperature until the temperature of weld surfaces has decreased to lower than the recrystallization temperature. The applied voltage and the upsetting pressure are controlled in accordance with the weld progress.

Abstract: A flash welding machine for butt welding the trailing edge of a preceding metal strip to the leading edge of a following metal strip in a rolling mill or the like. A preceding carriage and a following carriage are provided, movably mounted on a common set of rails. Each carriage is provided with electrodes capable of clamping respective ones of the preceding strip and the following strip when the two strips are in abutment with on another. Welding cylinders are provided for selectively joining the two carriers when the two strips are in abutment and the welding operation is to be performed, and then releasing the carriers from one another.

Abstract: A stud welding gun has a forepart which includes the delivery end of an automatic stud-feeder and is secured to the housing by a quick releasable joint so as to be readily replaceable by another forepart supplying a stud of different size. The gun includes a pneumatic piston and piston rod which serves to push a stud into the collet after delivery to the gun. The piston rod is detachable from the piston and means is provided for locking it in the forepart so that it is replaced into the forepart for studs of different size.

Abstract: A machine for electrical resistance welding of chain links has upsetting bars (10) which are engaged against the arcuate ends of a chain link (1). On either side of the welding zone the legs of a link are gripped by pairs of electrodes (12) attached to the ends of a two-armed clamp (14). The arms (13) of the clamp are mounted for pivoting in a plane at right angles to the chain link, and also about an axis in this plane extending at right angles to the upsetting direction and passing through journalling head (20) attached to the end of a piston rod (21) of a counteraction cylinder (20). The ends remote from the electrode jaws (12) of the clamp arms (13) are acted on by an operation cylinder (30) which, via a link system (16, 16), gives the clamp a gripping movement about the link leg. The cylinder (20) with cylinder (30) and the clamp (14) commonly form a welding head which is pivotable about an axis (z-- z) at right angles to the upsetting direction.

Abstract: An internal apparatus for flash welding pipes together in end to end relationship both under factory conditions and in the field, for example in laying trunk pipelines, comprises an elongate supporting member carrying an axially movable clamping assembly with electrode jaws for clamping one pipe, an axially immovable clamping assembly with electrode jaws for clamping the other pipe, and a doughnut-type welding transformer. The welding transformer is disposed at the side of the axially immovable clamping assembly, which is distant from the joint. The axially immovable clamping assembly is mounted on the elongate supporting member in a manner to provide an annular clearance therebetween such that there are extending therethrough two coaxial contact tubes, which are electrically insulated from one another and connect the welding transformer with the electrode jaws, whereby in operation a welding circuit is established.

Abstract: In a flash butt welder for joining strip ends, the improvement for improving the quality of flash butt welds made in specialty grade steels, such as high strength low alloy, as well as for considerably reducing the upset current requirement, by applying a protective atmosphere of combustible gas, such as propane, natural gas, or hydrogen during the flash butt welding process. Welds free from any detectable defects can be made with lower upset current densities thus extending the equipment welding capacity.

Abstract: A pipe resistance butt welding apparatus comprises a body with an elongated arrying member and two internal expanding clamps including current-feeding shoes. One of the clamps is rigidly attached to the body, whereas the other is movably mounted on the elongated carrying member and connected with a drive intended to communicate reciprocating motion to the other clamp. A trimming mechanism for removing flash is mounted on at least one of the internal expanding clamps. The body of the apparatus mounts centering supporting rollers and driving wheels, the former and the latter being secured thereto by means of spring-loaded levers. The driving wheels are connected with a rotation drive intended to rotate the wheels. The body carries a powder cylinder and spring-loaded three-arm rockers, the latter being turnably mounted. The first arm of each of said three-arm rockers carries a driving wheel, the second arm carries an additional supporting roller, and the third arm is connected with a rod of the power cylinder.

Abstract: The primary winding of a welding transformer is provided with controlled rectifiers and the primary winding of a current transformer. The secondary winding of the current transformer is connected to a welding current pick-up. The phase angle of opening of the controlled rectifiers is varied through a phase shifter and a programmer. A pulse shaper is provided for shaping pulses synchronized with the voltage of a supply circuit and has an output connected to a phase delay unit. An OR circuit is provided having inputs connected to the output of the welding current pick-up and to one output of the programmer, and an output connected together with the output of the phase delay unit through AND logical circuits and an inverter to the inputs of a voltage switching flip-flop having outputs each being connected in pair with another output of the programmer through additional AND circuits to corresponding inputs of the phase shifter.

Abstract: An electrical control circuit which provides means of initiating the start of upset of a flash welding machine at an operator selectable value of flashing electrical energy. The energy signal for this circuit is taken from an energy monitor, such as the output of the circuit shown in U.S. Pat. No. 4,084,075. The control circuit, by means of a single adjustment of electrical switch means, may include a few additional electrical components to enable initiation of the start of upset, or termination of upset, as a function of platen position rather than as a function of flashing energy. Further, by simple adjustment of additional electrical switch means, further electrical components may be included to control the distance the movable platen moves during the upset portion of the welding cycle. Also, a meter may be included in the circuit to display either upset distance or upset initiation.

Abstract: Improved apparatus and method for performing flash welding is disclosed. The apparatus moves adjacent surfaces of workpieces toward each other and applies electrical energy between them for flash heating the surfaces in a flashing step, after which it forces the surfaces together in an upsetting step, while continuing the application of the electrical energy for a predetermined time. Apparatus is provided for calculating and monitoring the amount of electrical energy applied to the workpieces during welding, along with control circuitry, for limiting the amount of electrical energy applied during the upset step to a predetermined function of that applied during the flashing step. An energy recorder produces an indication of the amount of electrical energy applied to the workpieces during welding.

Abstract: A welding apparatus comprises a pair of clamping devices for clamping the workpieces to prevent slip under applying significantly large force to the butting surfaces for the butt welding operation and a pair of electrode tables for feeding a welding current. The welding apparatus need not comprise a step gauge bar nor an auxiliary clamp in order to set the projecting degree.

Abstract: A bulge (12) formed by coldwelding two wire sections (10-11) is removed by advancing the wire through a bore (91) formed in a split cutting tool (64) having a pair of stepped-back tapered surfaces (92,96) at one end. The tapered surfaces terminate along a diameter of the bore to form a pair of spaced semi-elliptical cutting surfaces (93,97) which are successively rendered effective to remove semi-circular sections of the bulge. The apparatus includes facilities (31,32) for temporarily holding the wire in place within the cutting tool (64) and a clamping arrangement (35,36) for securely holding the wire during the weld bulge removal operation.

Abstract: A pipe resistance butt welding apparatus disposable within the pipes to be welded comprises a fixed expanding clamp and a movable expanding clamp, provided with clamping elements and actuating cylinders and intended to fix the pipes to be welded with respect to the apparatus. A cylinder to effect an axial movement of the movable expanding clamp is installed at the end at which this expanding clamp is located; the axial movement provides for drawing together the ends of the pipes to be welded in the course of fusion and upsetting. The cylinder for the axial movement of the movable expanding clamp is coupled with the actuating cylinder of the same clamp and with the clamping elements. The devices making up the apparatus and the cylinders are coaxially installed within a body wherefrom the clamp elements extend outwardly to engage the inner surface of the pipes being welded. Modifications of the apparatus for weld-joining of medium and large diameter pipes respectively are also described.

Abstract: Method and apparatus for detecting whether or not the gap in adjoining ends of a ring-like workpiece to be flash welded is of normal size, or is so much larger as to produce an unsatisfactory weld. The invention provides means whereby the amount the movable platen of a flash welder moves in a direction toward the stationary platen is compared with its position when the ends abut and flashing begins. If the ends are not materially beyond a predetermined normal gap, the welding action proceeds; however, if the ends are spaced beyond such normal gap, further action of the flash welding process is aborted, or a signal is activated; or both abortion and signal are provided. The invention is especially adapted for use in welding rings which are formed and welded in high production, such as rings that are further processed to make rims for tires of a vehicle.