Abstract: Disclosed is an automated cutting of a cylindrical workpiece. According to a method a cutting device is positioned, a motor is activated to rotate about an axis to cut the cylindrical element, and cutting the cylindrical element. Further disclosed is an apparatus and system to automate the cutting of a cylindrical workpiece.

Abstract: A device for dyeing columnar objects rotates the columnar object as they brush past an endless, absorbent, dye-carrying belt. The colored dye from the belt rubs off onto the columnar object, providing an even and consistent coating of dye.

Abstract: The invention described herein generally pertains to systems and methods for accurately and precisely mounting an orbital welder for static use. Clamp systems as described herein can include a keyed welding clamp assembly for retaining the orbital welder having an orbital welder clamp, a clamp adapter, and a clamp mount. Similarly, methods herein can include disposing a welder extension in a first extension recess of a first clamp portion and a second extension recess of a second clamp portion, aligning an alignment key with a first key recess of the first clamp portion and a second key recess of the second clamp portion, and closing the first clamp portion toward the second clamp portion using a clamp mechanism. An operational welding system including clamps herein can further include the orbital welder and/or components thereof.

Abstract: Provided is a pipe welding apparatus, including: a support fixed to the ground; a torch which is supported by the support and is formed to correspond to a welding portion of a pipe; and a first rotation part for rotating the torch in a circumferential direction of the pipe up to a predetermined angle.

Abstract: A welding bug (1) comprising a welding torch (3) for welding in a groove (19). The welding torch (3) is mounted for rotational movement about an axis (21) that is substantially horizontal, relative to the welding bug, (typically tangential to a pipe during use) so that the torch is moveable, during use of the welding bug (1) when arranged to enable the torch to weld in a groove, between (i) an operating position, and (ii) a disengaged position in which the welding torch is positioned away from the groove (19). The welding bug may be less cumbersome and more compact than some known arrangements.

Abstract: An apparatus for processing an inside of a pipe which performs various works from an inside of a pipe, includes traveling drive units, a working device, rotation support mechanisms, a coupling mechanism, and suspension devices. The traveling drive units are inserted into the inside of the pipe, and the working device is moved in a circumferential direction along the inside of the pipe by the traveling drive units.

Abstract: A welding apparatus (24) is adapted to be mounted on a guide ring, the welding apparatus comprising a housing (25), a pair of rollers (29, 31) mounted on each side of the housing, said pair of rollers comprising a first roller (29) having a tubular outer surface and a second roller (31) having a conical outer surface, the pairs of rollers being mountable on either side of a guide ring such that an edge of the guide ring passes between each pair of rollers, the conical roller (31) on one side of the housing being laterally movable within the housing (25). The guide ring (1) comprises two arcuate components (2) connected by a flexible hinge (11), and has a removable gear rack (6). A plurality of resilient spaces (8) are mounted on the inner surface of the guide ring (1).

Abstract: A welding bug (1) comprising a welding torch (3) for welding in a groove (19). The welding torch (3) is mounted for rotational movement about an axis (21) that is substantially horizontal, relative to the welding bug, (typically tangential to a pipe during use) so that the torch is moveable, during use of the welding bug (1) when arranged to enable the torch to weld in a groove, between (i) an operating position, and (ii) a disengaged position in which the welding torch is positioned away from the groove (19). The welding bug may be less cumbersome and more compact than some known arrangements.

Abstract: A welding head carrier for use in welding the inner surface of a tube includes inter alia a welding head provided with a welding torch and a camera, a wireless camera mounted at the inner side of the tube to monitor whether cables are entangled, a wireless receiver for receiving wirelessly an image from the wireless camera, including a camera controller for controlling the camera and the wireless receiver, display for displaying the welding operation and the inside of the tube. Fixing units can be adjusted in length depending on the size of the tube, thus eliminating the need for the rebuilding or replacement of the welding head carrier, leading to cost savings. The welding head can be easily mounted, regardless of size and configuration of the welding head, and the range of use of the welding head carrier can be extended.

Abstract: An apparatus for processing an inside of a pipe which performs various works from an inside of a pipe, includes traveling drive units, a working device, rotation support mechanisms, a coupling mechanism, and suspension devices. The traveling drive units are inserted into the inside of the pipe, and the working device is moved in a circumferential direction along the inside of the pipe by the traveling drive units.

Abstract: Method and apparatus for friction welding termination elements at first and second ends (21, 23) of a cylindrical shaft (15) in alaignment with an axis. A shaft receiver (17) receives the cylindrical shaft (15), and a first chuck (70) grips and rotates the cylindrical shaft (15) in alignment with the axis. A second chuck (75) grips the cylindrical shaft (15) and translates the second chuck (75) between first and second axial positions. A first termination receiver (155) receives the first termination (30) and axially translates same to a first installation position. An installation drive (90) urges the first termination (30) axially toward the cylindrical shaft (15) as it is rotated. A second termination receiver axially translates second termination (32) to a second installtion position in allignment with the axis. A second installation drive (91) urges the second termination element (32) axially toward the cylindrical shaft as it is rotated.

Abstract: This invention relates to a device for welding a flange (3) of a part (1) having a shaft (2) and the flange (3) to a steel plate (44). The device comprises a supporting shaft (26), on the end of which a hole (37) for receiving the shaft (2) of the part (1) is formed, a supporting member (27) fitted on the axis of the supporting shaft (26) in a rotary manner, a supporting pipe (33) fitted into the supporting member (27) and having a electrode wire (36) inside, and driving mechanisms (40, 41, 42). In this device, the electrode wire (36) is directed so as to face the flange (3) of the part (1), whose shaft (2) has been received in the receiving hole (37). To achieve this arrangement, the head (34) of the tip of the supporting pipe (33) is positioned near the opening of the receiving hole (37) on the end of the supporting shaft (26), wherein the tip of the electrode wire (36) moves around the flange (3) as the supporting member (27) rotates.

Abstract: An apparatus and method for precisely aligning and holding two thin walled stainless steel sanitary tubing segments end-to-end to allow for tack welding of the segments together during a tube assembly process are disclosed. The apparatus includes two pivotally connected C-shaped clamp halves that contact almost an entire circumferential path along the outer walls of both aligned tubing segments. The apparatus is not designed to reshape the ends of the tubing segments, but rather is designed for precision alignment of the ends of the tubing segments during the tack welding process. The process includes use of an apparatus constructed in accordance with the principles of the invention.

Abstract: A method and apparatus for creating second order vibrational modes. The apparatus includes a signal generator, a piezoelectric transducer, a plurality of wave propagating beams and reflecting boards. An electric field applied by the signal generator to the piezoelectric transducer induces a unidirectional vibration of the transducer. The vibration is propagated through the beams and reflected by the reflecting boards in a closed polygonal loop. The final reflection direction is perpendicular to the original vibration. A circular or elliptical vibration of the apparatus results. The circular or elliptical vibrational energy can be imparted to the wire bond of an integrated circuit to add strength to the connection.

Abstract: The present invention relates generally to an apparatus and method for performing tube-to-tubesheet welding within box headers and, in more particular, to a GTAW welding gun that has a long generally tubular barrel which is small enough in diameter to pass through the plug holes on one side of a box header and long enough to reach over to the point of connection on the opposite tubesheet. Additionally, and as a critical part of the instant invention, the torch is fitted with a semi-automatic cold wire feeding apparatus and an associated wire feed liner that is constrained to be proximate to the exterior of that tube throughout said barrel's length. Thus, both the barrel of the welding torch and its accompanying wire feed liner are sized to fit within and pass through a plug hole.

Abstract: A principle of surface interlocking wherein the imperfections of two parallel surfaces deform and interlock under pressure. The surface interlocking enables the combination of a bridging element and a bonding tip of a diffusion bonding apparatus to pick up, transport, position at a unique location, and bond the bridging element in place to the conductors or pads. In the invention a single point bonding tip as part of a bonding apparatus is used to pick up the, to be, bridging metal object transport it to the bonding site and perform the entire bridging bonding operation all in one sequence of steps.

Abstract: A method for welding horizontal pipe along the inner diameter of the pipe and outer diameter of the pipe to prevent weld root defects on the bottom half of the pipe.

Abstract: An apparatus for processing curved surfaces, in particular a pipe surface, using processing means which are guided over that surface at a distance thereabove by means of a guide to be pre-arranged on that surface, wherein the guide consists of a flexible body provided with two parallel edges witch extend some distance above the surface for processing, and a carrier for the processing means is provided with a follower system consisting of at least three follower members which are ordered in a triangle and which co-act with the edges, this such that the carrier follows the curved surface at a fixed distance during movement along the guide, whereby processing of the surface can be performed under uniform conditions which enhances precision and therefore quality.

Abstract: A workholder to hold a workpiece, especially an end fitting, in accurate axial and angular orientation for orbital welding. It can optionally provide protection for sensitive surfaces on a fitting during the welding and handling processes.

Abstract: A welding mechanism for build up of a conical surface includes a base assembly with a base gear fixedly mounted thereto, and a slide rail assembly rotatable about a base axis. The slide rail assembly includes a slide rail positionable parallel to the conical surface, a slide carriage moveable along the slide rail, carrying a welding torch, a rotatable lead screw in threaded engagement with the slide carriage, and a carriage gear rotatable with the lead screw and engaged with the base gear. Rotation of the slide rail assembly moves the torch on the slide carriage circumferentially along the conical surface, and, simultaneously, rotation of the slide carriage assembly, by inter-engagement of the carriage and base gears, causes the slide carriage to move along the slide rail carrying the torch radially along the conical surface, the torch moving in a spiral path, about the base axis, along the surface.

Abstract: An arrangement for providing a seal fillet weld on a titanium tube sheet and tube includes an enclosure having a closed top and an open bottom opposite the top. The enclosure is positioned over the tubes to be welded on the tube sheet. A rotating seal welding head is contained within the enclosure for performing the welding operation on the tube and tube sheet. Trapped air is purged from the enclosure and inert gas is provided to the enclosure for creating an inert gas atmosphere for facilitating the welding operation. A rubber gasket is used to seal the enclosure to the tube sheet for ensuring a sealed inert atmosphere.

Abstract: An apparatus for performance of cutting and welding operations includes an enclosure which encloses a drive motor and which supports a drive wheel and an idler wheel for driving the enclosure along a track. A first support rod projects from the enclosure and a second support rod is adjustably mounted on the first support rod. A torch for cutting and welding is adjustably mounted on the second support rod and a variety of linear and curved tracks are provided, thereby facilitating performances of cutting and welding operations on a range of workpiece configurations.

Abstract: An apparatus for forming circular weld joints includes a support frame, a motor having a primary drive shaft, a secondary drive shaft coupled to the primary drive shaft, and a hub mounting plate affixed to the support frame. A floating hub assembly is included and a chuck which is coupled to the secondary drive shaft and has at least one radially offset receiving bore. A MIG-type welding tip is rotated in a circular path upon activation of the motor to form a circular weld. Stabilizing guide members and depth guides are provided which extend outwardly from a support frame to ensure proper positioning of the welding tip during the weld forming operation.

Abstract: A clamping device for holding cylindrical workpieces having a nominal radius R which varies from a minimum of (R-A) to a maximum of (R+B), where A and B are the limits of the tolerance range for the nominal radius. The clamping device includes opposed clamp halves each having a clamp face adapted to be moved toward and away from one another and each of the clamp halves carrying a rigid collet element adapted to engage on opposite sides of cylindrical workpieces when the clamp halves are moved toward one another. According to the disclosure, each of the collet elements has a semi-cylindrical clamping surface extending inwardly from the clamp face of the respective clamp half. Each semi-cylindrical clamping surface has a radius substantially equal to R+B) with the center of the radius being offset outwardly of the clamp face of the respective clamp half an amount at least equal to (A+B).

Abstract: A mobile robotic platform and guide means therefor having a carriage with one or more uniquely constructed drive rollers having radially-extending metal filaments embedded in a complaint material and which coact with a track defining the guide means which has a length of textured material, such as wire mesh secured thereto. The coaction provides an infinite pitch rack drive. The mobile robotic platform can have the carriage thereof provided with two or more tractor units pivotally mounted thereto and each of which carry a pair of the aforesaid drive rollers whereby the carriage can follow guide means of varying contours with controlled travel and continuous operation of an operative device carried by the carriage.

Abstract: A track assembly for mounting a welding head assembly onto a pipe for the purpose of welding the pipe. The track assembly includes a flexible annular base which is to be located about the pipe in close proximity to the exterior surface of the pipe but spaced therefrom. Located between the annular base and the pipe are a plurality of spaced-apart foot pad assemblies. Each foot pad assembly includes a pair of contact pads which function to exert a continuous spring force between the annular base and the pipe. Each contact pad is connected to a separate spring assembly which can be mutually adjusted to vary the amount of spring force between the flexible annular base and the pipe. Mounted on the exterior surface of the annular base is a track which is to connect with the welding head assembly upon which the welding head operates to move circumferentially about the pipe. A latching assembly in the form of an over-center latching mechanism is used to secure together the free ends of the annular base.

Abstract: An apparatus for circumferentially and longitudinally positioning a weld head or other tool with respect to the surface of a pipe. A first annular ring is affixed to the pipe. A longitudinally movable annular indexing track is also circumferentially fitted about the pipe and rides upon a plurality of support rods mounted to the indexing track. The support rods are slidably received within corresponding holes in the clamping ring and extend longitudinally and parallel to the outer surface of the pipe. A motor mounted to the fixed ring drives a ring gear concentric to the fixed ring to reciprocate a ball screw which moves the second longitudinally moveable ring toward and away from the fixed ring. An orbitally moveable third annular ring is circumferentially mounted to the second ring, and a second motor mounted to the fixed ring drives a telescoping drive shaft which rotates the orbital third ring.

Abstract: A welding head base to facilitate the mounting of a welding head assembly thereon for the purpose of welding a joint between abutted ends of a pipe. The base is mounted on the edges of a thin, sheet material, continuous band track and is capable of low frictional movement, through a series of wheel assemblies, relative to the track. Each wheel assembly includes a wheel with each wheel including an enlarged flange to facilitate the mounting of the welding head base onto the track. Mounted on the fixed section of the base is a sprocket assembly with a sprocket wheel that is to be rotatably driven by a motor. The sprocket is to engage with a series of gear teeth formed within the track. The sprocket assembly is to be movable from an operating position (in engagement with the track) to a retracted position (spacing the sprocket wheel from the track). Movement of the sprocket assembly is caused through the use of a manually operated cam assembly.

Abstract: Welding carriage, including an articulated body having support wheel sets on its end sections, one of said end sections supporting a drive assembly movable toward and away from a track upon which the carriage travels, the drive assembly including two tandem drive wheels driven by an electric motor supported by the drive assembly. The carriage may support one welding head or plural welding heads, so that one or more weld beads may be formed as the carriage travels past a section of a welding groove.

Abstract: Track to provide travel of a welding carriage about a pipe, including a metal band bent to encircle a pipe and being supported by slotted crossbars, the slots of the crossbars providing resiliency to the band so that the band will yield when tightened about the pipe, and so that the pipe may expand and contract under changes in temperature without longitudinal overstressing of the band and the latch connecting the ends of the band. The invention includes locator apparatus for spacing the track from the end of a pipe, including one or more adjustable locking pliers fitted to provide pipe end and track engagements and suitable to serve as a guide for locating the position of the track with respect to the pipe end.

Abstract: A welding device for building up metal for repair or construction of a metal bores, outside diameters and circular faces by laying down single or continuous metal weld beads in a pre-selected pattern; including a base member to receive a rotatable table with a drive is provided on the base to rotate the table at selected speeds. An elongated tubular spindle is provided to rotate with the table. Conduits for welding wire, welding current (power) and a shielding gas supply is provided to the spindle to supply gas, power and wire to the area adjacent the point of exit of the wire. The tip of the spindle serves as one electrode contactor in a welding process and the metal to be welded serves as the other.

Abstract: A device for overlay-welding a pipe interior having an arm extensible into the interior of a respective pipe, the arm carrying a welding head at a free end thereof includes a rotating device in the form of a wheel surrounding and supporting the pipe, and a swiveling device disposed in the wheel for moving the pipe in a circular arc about the center of the wheel and transversely to the plane of the wheel, the arm being curved and being secured to a part of the swiveling device connected to the wheel, the welding head being rotatable in the plane of the wheel for overlay-welding pipes formed at least partly with a bend therein.

Abstract: A new and improved fillet welding equipment is disclosed which can be used to butt a pipe member against a plate-like surface and then weld the entire periphery of the butted pipe member. In this fillet welding equipment, a pair of welding torches are arranged such that their respective nozzles are opposed to and spaced about 90 degrees from each other. This pair of welding torches can be rotationally moved simultaneously and continuously through their respective predetermined ranges of about 90 degrees to weld one half round section of the entire periphery to be welded, which results in the reduced welding time.

Abstract: An elongate deformable ribbon drive rail for carrying a working apparatus having a toothed drive gear and support mechanism is provided in the form of a first narrow elongate strip of metal of width to carry the support mechanism, a second narrower strip of metal having a regular series of corrugations extending lengthwise thereof fixed to the first strip intermediate its edges at each valley of the second strip and adapted to be engaged by the toothed drive gear while the edges of the first strip engage the support mechanism.

Abstract: An apparatus for supporting and moving tools for fixing a cluster of tubes to the tubular plate (2) of a steam generator, comprising a first running track (25), a carriage (26) movable on this track, a horizontally alignable support (39) resting on the carriage 26, a second running track (43) carried by the support (39) and perpendicular to the track (25), and at least one supporting structure (42) consisting of a base (45) movable on the second running track (43) and carrying a vertical column (46), a tool holder (54) being mounted to move on the column (46) to offer a tool opposite each of the holes in the plate (2) in succession by virtue of a motor driven guiding and displacing elements (53-55) carried by the column (46) and of elements (31, 50,51) for moving the carriage (26) and the structure (42). The invention applies particularly to assembling the steam generator of pressurized-water nuclear reactors.

Abstract: A guide apparatus comprises an annular rail and jaws for attaching the annular rail onto a cylindrical member to be inspected by an inspecting probe on the rail. The attaching jaws are provided on the rail and include at least two radially stationary jaws and at least one radially movable jaw. Each of the radially stationary jaws has a jaw surface to be abutted on an outer periphery of the cylindrical member. A radial distance between the abutting surface of the radially stationary jaw and the inner peripheral surface of the rail is discontinuously variable.

Abstract: Apparatus for automatic welding of complex contours made up of rectilinear and curvilinear portions. Such apparatus includes first and second movable carriages guided for reciprocation in directions parallel to each other and having a welding torch, a driving unit, and a gear rack with which a driving gear is permanently in mesh. The gear rack is permanently affixed to a first one of said carriages whereas the driving gear is mounted upon a shaft fixedly journalled upon the other of the carriages. The first and second moving carriages are mounted on first and second drive screws, respectively, which are connected to the driving unit by means of a selective motion reversing mechanism. The welding torch is affixed to the shaft bearing the gear which is in mesh with the rack. If suitable torches are used, the apparatus can also be used for cutting, building-up, and surfacing operations.

Abstract: The disclosure concerns a procedure for replacing a worn bolster ring on a freight car truck bolster which utilizes a motorized circle cutting and welding machine which rests upon the bolster and is centered by supporting structure positioned by locating pins which engage two pairs of mounting holes for the side bearing cages. The worn ring is cut from the bolster by a cutting torch driven around the circumference of the ring by the motorized machine. Then, the replacement ring is placed on the cut bolster surface, centered with respect to the axis of the motorized machine and tack welded, and finally welded to the bolster by a welding head which traverses the inner and outer peripheral surfaces of the ring under the control of the motorized machine.

Abstract: A method of repairing the housing of a control rod driving system of a nuclear reactor, the housing being inserted through the wall of a pressure vessel of the reactor into a cylindrical sleeve secured to the inner surface of the vessel, which housing is jointed by welding to the cylindrical sleeve. The method comprises the steps of: cutting the housing in the circumferential direction of the housing at a position defined between the weld joint and the inner surface of the reactor vessel and surrounded by the cylindrical sleeve, thereby to divide the housing into a first housing part still attaching to the weld joint and another removable housing part; removing the removable other housing part; inserting a second housing part into said cylindrical sleeve through the wall of the nuclear reactor vessel; and uniting the first housing part and the second housing part by welding thereby to form a new housing for the control rod driving system.

Abstract: A semiautomatic weld grinding apparatus for grinding the surface of a weld seam interconnecting two perpendicularly disposed tubular sections. The grinding apparatus is capable of grinding off excess weld from a saddle-type nozzle to shell weldment that follows a circular path through a plurality of planes. Alternatively, the apparatus is adaptable to function as a welding or a cutting apparatus that follows the saddle-shaped path created at the interface of two perpendicularly disposed tubular sections.

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: 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 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: 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: An improved smoke exhaust apparatus for a rotary welder which comprises an elongated stationary carrier having a support member mounted thereon for rotation about an upright axis. Plenum and shroud elements are vertically spaced apart and are connected to such support member for rotation therewith. The plenum is provided with intake and exhaust ports. The shroud includes a horizontally disposed plate having a depending skirt around a portion of the periphery thereof to provide an opening in the side of the shroud. Smoke inlet ports are provided in the plate and tubes connect the smoke inlet ports to the respective intake ports whereby suction applied to the exhaust ports of the plenum causes flow of air from the interior of the shroud upwardly through the smoke inlet ports, the tubing and intake ports and into the plenum from which such flow passes outwardly of the exhaust ports.

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 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: Apparatus comprising a frame disposable in spaced relationship about a pipe uses a ring mounted thereon for carrying a welding head around the pipe. A welding torch is provided on the head for movement into the welding area to form a weld about the pipe during rotation of the ring.

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.