Abstract: An internal bore welding torch assembly and method for use in making remote arc welds inside metal tubes. The torch assembly includes a torch body unit of plastic electrical insulating material, to which is connected the necessary welding services of coolant, shield gas, and electric power. The body unit contains a removable and rotatable welding wand which is made of flexible plastic and has a welding electrode oriented radially at its outer end. For making a weld, such as for repairing a damaged tube, a metal sleeve is first inserted into the tube the flexible welding wand is then inserted into the tube and the radial electrode positioned adjacent an end of the sleeve. The flows of coolant and shield gas are provided through the torch body unit to the wand, and the wand is rotated while making the metal arc welds desired to seal weld the sleeve ends to the tube.

Abstract: A tube sheet welding apparatus for the rear or back face of a tube sheet. The welding head apparatus includes a welding head housing with an internal opening therethrough. The particular tube to be welded is to be located through the internal opening. The welding head housing is to be separatable into two separate halves and to be clamped tightly onto the tube to be welded. The welding electrode is mounted within a welding electrode housing which is located within the welding head housing. The welding electrode, as well as the welding electrode housing, is rotated through a gear assembly to complete the welding operation of the tube to the tube sheet. After welding, the welding head housing is split apart permitting separation of such from the tube that has now been welded permitting movement of the welding head housing to another tube that is then to be welded. Inert gas is to be supplied to the welded area through an inert gas passage assembly located within the welding head housing.

Abstract: The welding head assembly for welding together a pair of cylindrical tubes wherein one of the tubes protrude along with a mass of other similar tubes from a tube sheet. To precisely locate the welding head position at an exact position for each and every produced weld there is utilized a locator plate assembly which is to be fixedly mounted a precise distance from the tube sheet directly on to the tube which protrudes from the tube sheet. The locator plate assembly includes a position locator mechanism which connects with the face of the tube sheet to precisely locate the locator plate assembly a precise distance from the tube sheet. A location gage assembly is to connect with the locator plate assembly to initially establish the desired position for the locator plate assembly. Upon removal of the location gage assembly from the locator plate assembly, a welding head is to be engaged with the locator plate assembly.

Abstract: A device for welding together coaxial tube sections, comprising a cage adapted to surround the extremities of said tube sections, and provided with sleeves to be clamped on said tube sections for aligning the latter, guiding means for welding electrode carriers being connected to said sleeves which are adapted to guide welding electrodes and associated equipment along the welding seam to be formed between said tube sections.

Abstract: In order to join a tube to a tubesheet of a heat exchanger, the end of the tube is inserted into a socket at the end of a hole that passes through the tubesheet. The socket is large enough to receive the tube, but the hole is not, so the tube bottoms out in the socket and is thus located both radially and axially by the socket. A ring mold is fitted around the tube and moved against the tubesheet, so that its end fits into an annular groove that surrounds the socket in the back face of the tubesheet. The ring mold has a chamfered confining surface that surrounds the tube where the tube emerges from the socket. Once the ring mold is in place the portion of tube that is within the socket is welded autogenously to the tubesheet by rotating an electrode within the hole. The molten weld metal flows outwardly to the confining surface, but is prevented by that surface from flowing circumfentially, even when the welding is performed with the tube in a horizontal position.

Abstract: Internal pipe welding apparatus, including a pair of internal pipe clamps between which is disposed a rotative welding head support. The welding wire and gas feed conduits are disposed through passages through the central hub of one of the clamps. The welding head support is rotated by a ring gear engaged by a gear carried by a shaft disposed through a passage of the central hub of the other clamp. The gear engagement with the ring gear is adjustable to minimize vibration and chatter. The welding wire feeders are mounted on a block support at the front of the first mentioned central hub.

Abstract: A welder for automated closure of fuel pins by a gas tungsten arc process in which a rotating length of cladding is positioned adjacent a welding electrode in a sealed enclosure. An independently movable axial grinder is provided in the enclosure for refurbishing the used electrode between welds.

Abstract: A tungsten electrode (35) is positioned adjacent the root face (15) of a tube (10) with the tube and the electrode being connected to a source of direct current (40) such that the electrode is positive with respect to the tube. The electrode is mounted in an assembly (30), and the assembly is provided with a shielding gas from a source (48). The electrode assembly is mounted for rotation on an orbiting head (60) with the electrode axially spaced from the root face. As the electrode is rotated about the tube, the root face (15) and a portion (20) of the inner surface and a portion (25) of the outer surface are simultaneously cathodically cleaned. Preferably, the electrode (35) cleans the root face from two to four times in preparation for a subsequent welding operation.

Abstract: The adapter is arranged to be mounted to the horseshoe travelling carriage for a weld head in a pipe welding system to support the torch or weld head at an acute angle to the plane of rotation of the travelling carriage and thus to a plane normal to a pipe axis. This positioning of the weld head or torch facilitates socket welding; that is, welding about the intersection point of larger and small diameter pipes. The adapter comprises a mounting plate and a movable plate supported at an angle to the mounting plate by appropriate guide rods. Left and right racks adjacent to the guide rods and secured to the movable plate are driven by a single pinion bridging the racks and mounted between fixtures secured to the mounting plate. The movable plate is constrained from movement in a plane parallel to itself by the guide rods. A motor operates the pinion so that the weld head can be moved closer to and further from the socket area to be welded as appears necessary to effect a high quality weld.

Abstract: A confined space welding apparatus which is to interiorly weld a tube to a structure such as a wall of an enlarged chamber. The position of the weld bead is initially determined through a set gage. This set gage is then employed to accurately position the welding electrode within the welding apparatus. The welding apparatus is includes collapsible handles to facilitate insertion of the welding apparatus within the enlarged chamber. The collapsible handles are then moved to their extended operable position and then the welding apparatus is securely clamped within a conduit positioning the welding electrode at the area to be welded.

Abstract: An orbiting welding head for welding tubing and the like together. A U-shaped tube clamp unit has a pair of jaws in which two tubing sections to be welded together are held with the edges of such tubing sections in abutment against each other. A welder unit is incorporated in a cassette having a housing with an electrically non-conductive outer wall portion. This cassette is inserted into the U-shaped tube clamp and removably joined thereto by means of a locking ring. The welder unit has a welding electrode which protrudes from a horseshoe shaped rotatable electrode drive member. This drive member has a ball bearing support which comprises a plurality of ball members which protrude from the rotatable drive member at the opposite side faces thereof and which ride in respective grooved races formed in the main body of the cassette. The drive member is rotatably driven by means of a motor driven gear train.

Abstract: A welding apparatus for pipes which provides for a guide means which is to be fixedly secured to the pipe adjacent the welding area, a first carriage and a second carriage is movably supported upon the guide means with each of the carriages supporting a pair of spaced apart welding heads. Attached to the guide means is a driving chain. Mounted on each of the carriages are motor means which, in turn, operate through the driving chain to move the carriages in a prescribed manner with respect to the guide means. The welding heads of each of the carriages move within the same plane but each are movable in a separate one hundred and eighty degree arc thereby forming a continuous circle. Associated with each welding head is a weld groove tracking system which automatically maintains each welding head correctly aligned within the welding groove. The entire apparatus of this invention, when combined with appropriate electronic computer equipment, automatically welds an adjoined pair of piping sections.

Abstract: A pipe clamping structure is arranged to clamp an in-place pipe to be welded. A welding mechanism in turn is coupled to the pipe clamping structure for rigid guided movement in directions parallel to itself towards and away from the clamping structure in an axial direction along the pipe. The welding mechanism in turn supports a horseshoe-shaped weld head support rotor which receives the pipe in the horseshoe opening and is arranged to rotate about the pipe axis. A torch head is carried on the horseshoe rotor so that a 360.degree. weld can be achieved and simultaneously, the welding mechanism can be oscillated back and forth by the rigid guidance and alignment coupling with the clamp structure. In addition, the torch head is held on a link plate to the rotor, the link plate being swingable to vary the arc gap and thus provide appropriate voltage control.

Abstract: The invention relates to a method and an apparatus to perform plasma welding, by providing a cooling water temperature detector at the inlet side of cooling water in the plasma welding torch, controlling the temperature at the inlet side of the cooling water running into the plasma welding torch at a set temperature of more than 4.degree. C. and less than 18.degree. C., starting a plasma arc when the temperature of the cooling water reaches a specified point after starting to pass the cooling water, and moving the base metals and the torch relatively upon lapse of a specified time allowed to form a keyhole after start of the plasma arc.

Abstract: An arc welding system for welding the edges of an irregularly contoured product comprising facially opposed sections held in joined position wherein, in the embodiment illustrated, a pair of arc welding torches, having arc generating tips are supported in product straddling relationship on a carriage for welding travel along different irregularly contoured lengths of the perimetral marginal boundary of the product, and control mechanism is provided for simultaneously altering the position of each torch tip in a portion of its welding travel to maintain each torch tip axis substantially perpendicular to the path of travel.

Abstract: The method includes aligning a first plurality of cylindrical workpieces of a first diameter such that the longitudinal axes thereof are substantially coincident and welding the workpieces together end-to-end to form a cylindrical member of a desired length. The welding step includes rotating the workpieces about their longitudinal axes while maintaining a welding electrode at a fixed position along the workpieces and at a fixed distance from the outer circumference of the workpieces. The method includes cutting openings in the cylindrical member wherein the cylindrical member is rotated about its longitudinal axis while causing a cutting means to move linearly along the length of the cylindrical member. In one embodiment, the method is repeated with a second plurality of cylindrical workpieces of a greater diameter with some of the steps in processing the first and second plurality of workpieces being carried out at substantially the same time. Other forms of the apparatus and method are disclosed.

Abstract: A welding apparatus which is designed to weld together tubular members having any exterior configuration. The welding electrode is mounted on mounting structure which in turn is movably mounted upon the periphery of a housing. The workpiece to be welded is fixedly secured and centrally disposed within the housing. The welding head is to move about the workpiece and also tilt in respect thereto to maintain the longitudinal center axis of the welding electrode continuously perpendicular to the workpiece surface. Step motors are employed to both drive the welding head about the workpiece and also tilt the welding head with respect to the workpiece. The particular exterior configuration of the workpiece has been preprogramed into a memory unit. The memory unit operates through an electronic circuit to operate the step motors to locate the welding head at the precise desired location along the entire length of the welding path.

Abstract: A welding torch made of a high temperature plastic which fits over a tube intermediate the ends thereof for welding the juncture between the tube and the back side of a tube plate and has a ballooned end in which an electrode, filler wire guide, fiber optic bundle, and blanketing gas duct are disposed.

Abstract: Herein disclosed is an automatic welding apparatus which comprises an arcuate frame including a welding unit and a pair of wire feeders, and an arcuate frame including a running truck and a pair of clamping mechanisms for fastening the outer circumference of a pipe to be welded. The aforementioned two arcuate frames are detachably connected at two positions thereby to form a ring shape. Thus, the pipe is automatically welded while the truck is being made to run in the circumferential direction. The running truck of the welding apparatus thus constructed carries both a mechanism for effecting close contact with the outer circumference of the pipe and a shock absorbing mechanism so that the distance between the leading end of a welding torch and the outer circumference of the pipe may be constant at all times.

Abstract: A compact welding wire feed device is provided capable of being mounted directly on a welding head carriage. The device comprises a ball bearing having an inside race with tangential entrance and exit guides to the race adjacent to opposite axial ends of the bearing. A hub member has an outside diameter less than the inside diameter of the race so that the hub member can be coaxially received in the race and a welding wire passed through the entrance guide and wrapped around the hub and out the exit guide. By now side-loading or expanding the hub against the inside of the race and driving the hub rotationally, the welding wire is continuously fed out the exit guide. The coaxial relationship of the hub and race provides for a very compact structure thereby permitting mounting of the wire feed directly on a welding head carriage adjacent to a weld head or even permitting the feed wire itself to be used as an electrode in a MIG welding system.

Abstract: A method and apparatus for welding girth joints in pipelines using two welding heads comprises the steps of moving each of the welding heads upwards around the pipeline along the respective section of the girth joint, feeding a welding wire to each of the welding heads so that the welding wire is fed substantially tangentially with respect to the surface of the pipe, and forming a circumferential weld by moulding it to hold the molten metal of the welding bath in the welding zone. An apparatus for carrying out the method for welding girth joints in pipelines comprises an annular track structure having at least two carriages mounted thereon which are connected with drives adapted to impart a translatory motion to the carriages. Each of the carriages carries a welding head provided with a welding wire feeder and a weld moulding member arranged opposite to the joint being welded.

Abstract: Welding apparatus utilizing a continuous belt in conjunction with a slidable guide pin and spindle disposed in a carriage that causes a welding torch to form a circumferential weld when the guide pin is in a tube and moves the torch rapidly between the tubes when the guide pin is retracted from the tubes.

Abstract: Pipe welding clamp apparatus, including a pair of clamp assemblies, one being of conventional design and the other being of a special design permitting access to the axial space between the clamp assemblies so that internal welding assemblies may be disposed partly within said axial space and partly at a location opposite said special clamp assembly from said axial space. Each welding assembly includes a relatively large welding electrode reel and an electrode feeder at said location, communicated with a torch assembly in said axial space through a flexible tube. Each torch assembly includes means for torch position adjustments angularly and radially, and includes novel means for oscillating the torch so that a wider root weld is formed which will bridge the welding gap between adjacent pipe ends in spite of torch position misalignment and in spite of irregularities in pipe alignment and welding gap width. Novel clamp locator means and wheel support means are also disclosed.

Abstract: A welding process, such as a GMA welding process, employs a consumable electrode with the consumable electrode being oscillated back and forth over the surface of an object to which welding material is to be applied or across the gap between two pieces of metal to be welded together. At the ends of the swings of the consumable electrode an impact force is applied to the consumable electrode to interrupt its movement, thereby causing molten metal at the end of the consumable electrode from which the arc is struck to be impelled therefrom.

Abstract: The apparatus includes a pair of rotatable headstocks which are spaced apart. A side beam extends along at least a portion of the distance between the headstocks with the side beam being substantially parallel to a line connecting the centers of rotation of the headstock. The headstocks are respectively of a configuration to securely receive an end of a first one of a plurality of cylindrical workpieces. Support means is provided for rotatably supporting the plurality of cylindrical workpieces in end-to-end manner with the longitudinal axes thereof being substantially coincident. Controllable welding means and controllable cutting means are coupled to the side beam and are capable of linear translation therealong. Controllable drive means is provided for: rotating the headstocks so that the cylindrical workpiece secured thereto is caused to rotate about its longitudinal axis; causing the welding means to translate along the side beam; and causing the cutting means to translate along the side beam.

Abstract: Traveling carriage apparatus, adapted to travel along a track disposed about or upon an object, to carry a device such as a welding torch to do work upon the object or upon other apparatus supported thereby. The apparatus is hinged end-to-end, preferably having three hinged-together portions, the angularity at the hinges being adjustable so that the apparatus may travel along a track which is either curved or flat. The apparatus is supported by track-engaging sets of wheels at its opposite ends. A retractable drive wheel assembly is carried by one of the hinged portions of the apparatus.

Abstract: Gas-shielded, arc welding apparatus for securing a tube to the sidewall of a pipe or the like and facilitating removal of the welding apparatus after completion of the weld includes a locating fixture adapted for clamping engagement with the pipe and for positioning a welding head with rotary guide means coaxially aligned with the tube, a welding torch assembly being supported for rotation upon the guide means and supplied with power during rotation for welding the tube to the pipe.

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: One or more pairs of vertically-spaced-apart sidewardly-aimable plasma arc cutting torches, the upper one angled upward and the bottom one downward, on the end of a horizontal boom movable longitudinally fore and aft and angularly sideward, are used to double-cut the tube bundle of a steam generator progressively in a manner clearing a path that accommodates torch assembly advancement.

Abstract: An automatic welding apparatus including a movable welding torch carried by a composite frame adapted to control the relative position of the torch with respect to a workpiece holder. Either the workpiece holder or composite frame may be supported on a movable base comprising a truck mounted on a track for movement in a longitudinal direction. The truck is capable of being fixedly positioned at a number of predetermined work stations along the track.

Abstract: The bellows sections welder according to the invention comprises a bed carrying a stationary support and a movable support with a driver chuck and a driven chuck, respectively, which chucks are kinematically interconnected. The bed further carries a welding torch and a yoke disposed between the chucks and intended for centering the ends of bellows sections being welded. The movable support is driven by at least two pneumatic cylinders symmetrically arranged with respect to the longitudinal axis of the welder. Viewed in the direction of the work movement, the movable support is preceded by adjustable stops and followed by a means to receive welded bellows sections.

Abstract: A machine for the automatic welding of circular assemblies, comprising a fixed frame provided with means for receiving and holding an assembly to be welded, a welding-platform rotatively mounted on said frame, a drum rotatively mounted on said fixed frame about an axis parallel to the axis of said platform, a first and second spools constituted by a portion of said platform and of said drum, respectively, means for feeding the welding torch, sheaths for guiding said feeding means, one end of each sheath being fixed to said drum while its other end is fixed to said platform, and means for rotatively driving said platform and drum simultaneously.

Abstract: In the welding of tubes with bevelled ends without heels or root-faces, all the weldings beads are made from the outside of the tubes with the tubes being in contact with local gap not exceeding 2 mm. The first and second welding beads are made both by the up-hill method and the down-hill method with the axis of the welding torches at the same inclination to the normal or the radius of the pipe and the accuracy of welding is improved by the use of mechanical guiding means for the welding means comprising at least one roller which bears on the bevelled ends of the tubes adjacent the welding zone.

Abstract: A welding device for operating in exiguous spaces, in particular for butt-joint welding parts, e.g. tubes, includes a rotor equipped wih an orbiting welding-torch and connected to a driven motor through a flexible transmission member. A control and feed device communicates with the rotor and the torch through the flexible transmission member.

Abstract: A method for assembling successive ducts end to end with a pipe-line constituted by the assembled ducts comprising: providing inner equipments for said ducts each comprising means for vacuum-tight connection with the inside of a duct and means protruding from the duct for vacuum tight connection with the pipe-line; placing said inner equipments in each successive duct in an equipping station, connecting said equipment to the inside of the duct at both ends to close an inner vacuum tight space inside the duct; connecting said space to pumping means and evacuating said inner space by said pumping means while transferring said duct and inner equipment from said equipping station to a welding station; positioning said duct in alignment and abutment end to end with the pipe-line in said welding station; locking the duct in fixed position with respect to the pipe-line, sealingly connecting said equipment with the pipe-line inside the pipe-line, and sealingly connecting a vacuum tight welding chamber of a rotative w

Abstract: An orbital welding apparatus for butt welding tubular pipes includes a non-consumable electrode for establishing an electrical arc and means for storing and dispensing consumable weld wire through an aiming conduit. The weld wire is a solid monofilament wire helically coiled into a plurality of closely spaced convolution having a hollow core to provide minimum bending stiffness and a low constant spring rate in the bending mode so that it can negotiate sharper bends without permanent deformation. It is stored around a spool which is rotatably mounted in a non-rotatable magazine having a fixed block at one end. The fixed block supports a friction member formed by a plurality of axially projecting spaced loops of resilient filaments which engage the smooth end of the spool to provide a low uniform frictional drag balancing the low spring force of the weld wire as it is uncoiled from the spool and is fed to the aiming conduit by a pair of powered feed rollers having a resilient outer periphery to grip the wire.

Abstract: Apparatus for precisely positioning the seam on an end of a nuclear reactor fuel rod opposite from a welding electrode in a weld chamber. The circumferential seam is formed by abutting surfaces at the end plug-fuel tube interface, and it is important that the seam be located in an exact position relative to the welding electrode tip. This is accomplished by providing a stop member against which the fuel plug rests during the time an end plug is welded. The distances are chosen such that when the end plug is fully seated in the stop member, the electrode tip and seam will be located in optimum positions to effect the making of high quality welds. Open communication is established between the inside of the fuel rod and vacuum equipment which is used for evacuating the fuel rod of air or other gases during the welding operation through an axial passageway in the stop member.

Abstract: A TIG pipe welding method which employs two sets of machine guide surfaces on the pipe ends. First radially inner guide surfaces cooperate with a sensor coupled to the welding torch to continuously monitor the arc gap between the welding electrode and the weld puddle as the welding electrode moves around the circumference of the pipe. The second set of radially outer surfaces cooperate with a welding carriage to guide the carriage and welding modules around the pipe joint. The carriage is constructed to provide a sealed welding chamber surrounding the electrode. An additional flow of shielding gas is provided around the torch electrode of a TIG or hot wire TIG welding module to augment the normal gas shield.

Abstract: A compact automatic pipe welding apparatus having a base member separable into three sections and having a welding unit, detecting unit and a driving unit which are distributed on the circumference of the base member at an equal distance from one another is suitable for use in welding work in limited space, as is the case of installation or repair of pipings in nuclear or chemical plant. For enhancing the welding precision, ring gears are provided for interlocking a plurality of clamping means for securing the base member to the pipe stably.

Abstract: A welding machine for welding pre-weld flanges and slip-on flanges onto pipes which includes an upper welding station and a lower welding station for respectively welding a flange onto a pipe from the outside and the inside of the pipe. Both welding stations are as a unit supported by a stand.

Abstract: Apparatus for rapid and automatic welding of joints which interconnect sections of pipe, and in particular oil or gas transmission pipe. The system includes at least one torch transport assembly which simultaneously moves a plural number of welding torches along a path parallel to the pipe joint being welded. The torch transport assembly includes track segments which surround circumferential portions of the pipe joint, with a welding torch carrier and multiple torches being independently movable along each track segment. The torch transport assembly is mounted on a support apparatus which is rigidly clamped to the pipe sections during welding, and which permits the torch transport assembly to be rapidly positioned in rough alignment with a pipe joint. The torch transport assembly and selected operating parameters of each welding torch are adjusted to accurately position each torch with respect to the pipe joint, and to repeatably provide programmed welding parameters resulting in a uniform pipe joint weld.

Abstract: Apparatus is disclosed for transporting heavy equipment such as welding current generators, a prime mover therefor, and associated devices or supplies, on and along a pipeline, the pipeline serving as a monorail. The apparatus, of elongated construction along the pipeline, is supported at one end and propelled along the line by power driven traction means engaging the top part of the pipeline. The opposite end of the apparatus is supported on a pair of laterally spaced swivel mounted wheels which engage the sides of the pipeline laterally away from and somewhat below the top of the line. The latter wheels give lateral support and stability to maintain the apparatus in a substantially upright position on the pipeline. Sensing means, such as a pendulum, mercury switch means, or equivalent, detect incipient tilting or motion towards instability and are used to steer the swivel mounted wheels, either directly or indirectly.

Abstract: A machine for automatic weld of abutting pipes or accessories for ducts, or generally of circular solids, by the TIG or PLASMA process, with or without weld metal, comprising a control unit for programming the weld parameters according to cycles suitable to the different types of welds, and a stationary body which can be tightened on the pipes to be welded, supporting a welding torch capable of performing a multiplicity of revolutions about the pieces to be welded, comprising means for tightening said machine on the ends of the pipes to be welded, comprising an element fixed to the body of the machine, and an element movable with respect to the stationary element; means for positioning the welding torch with respect to the ends of the pipes to be welded; means for rotating in a controlled way said torch with respect to the ends of the pipes to be welded, so as to render possible to change several times, even during the same revolution, besides between one revolution and the next one, the welding parameters (s

Abstract: Disclosed is a control apparatus for an automatic pipe welder, for controlling the automatic pipe welder which continuously butt welds pipes while it is running along a welding line on the periphery of a pipe, in accordance with predetermined welding conditions for each of a plurality of welding areas sectioned along the welding line. All of the welding conditions for the welding areas are stored in a digital storage device while welding conditions on an area currently being welded are stored in another storage device. The contents of the second-mentioned digital storage device are converted by a digital-analog converter to analog signals, which are then held respectively in corresponding sample and hold circuits. Outputs of the sample and hold circuits are supplied as control commands to respective control units which control the welder in accordance with the welding conditions. In this manner, the construction of the control apparatus and a control panel thereof is simplified.

Abstract: The orbital welding torch described herein has a horse-shoe shaped body arranged to engage partially around the tubes to be butt welded when inserted from one side of the tubes, and a crescent shaped table carrying a welding head which is rotatably carried by the body so that rotation of the table relative the body orbits the welding head around the region of the weld, the open mouth of the table being capable of alignment with the open mouth of the body to enable the body to be inserted from one side of the tube to engage partially around the tubes.

Abstract: An apparatus for welding the adjoining ends of annular work members, such as lengths of pipe, employing an arc nozzle for melting and depositing metal in the gap between said adjoining ends. A drive motor coupled to the nozzle drives the nozzle laterally back and forth across the gap while the current that flows in said arc is integrated to generate a physical representation of magnitude of the integral. Means are provided to arrest the motor each time the magnitude reaches a predetermined threshold value, and to reverse the direction of travel of the motor.

Abstract: A tool holder head, particularly for supporting a welding yoke or gun in a welding machine, enables the welding gun to be moved in three degrees of freedom. The head comprises a bushing rigidly mounted on a movable support member of the machine and three hollow shafts movably mounted one within the other in the bushing and each driven by a separate motor and connected by gear means to a tool support.

Abstract: A welding torch assembly including a torch base, and a torch body which can be rapidly removed from the torch base and replaced without the use of tools, and without separately disconnecting welding current, coolant, or shielding gas lines.

Abstract: Method for controlling an automatic pipe welder is disclosed. In the automatic welder which requires remote control, welding conditions for butt welding pipes are stored and an actual joint geometry or groove shape is sensed. From signals relating to the stored welding conditions and the sensed groove shape, a control command signal in actual welding is produced to effect welding under an optimum condition. On the other hand, an arc condition at an actual welding point and a melting condition of a metal are monitored and displayed to modify the welding conditions in accordance with the monitored condition to control the automatic pipe welder.

Abstract: Apparatus for rapid and automatic welding of joints which interconnect sections of pipe, and in particular oil or gas transmission pipe. The system includes at least one torch transport assembly which simultaneously moves a plural number of welding torches along a path parallel to the pipe joint being welded. The torch transport assembly includes track segments which surround circumferential portions of the pipe joint, with a welding torch carrier and multiple torches being independently movable along each track segment. The torch transport assembly is mounted on a support apparatus which is rigidly clamped to the pipe sections during welding, and which permits the torch transport assembly to be rapidly positioned in rough alignment with a pipe joint. The torch transport assembly and selected operating parameters of each welding torch are adjusted to accurately position each torch with respect to the pipe joint, and to repeatably provide programmed welding parameters resulting in a uniform pipe joint weld.