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: Improved methods and apparatus for welding, wherein during welding the welding electrode is oscillated laterally of the weld path, and the welding current pulse frequency and oscillation frequency are correlated whereby weld metal droplets are deposited when the electrode is at its limit of movement away from center at each side of the weld path. During each cycle of oscillation of the welding electrode, a controlled number of weld metal droplets is deposited at each side of the weld path. An electrical circuit controls the electrode oscillation frequency and the welding current pulse frequency to be in correlation, and controls the number of weld metal droplets deposited at the opposite sides of the weld during each oscillation of the welding electrode.

Abstract: Method and apparatus for double jointing pipe, wherein a first pipe section is moved onto a pipe support roller assembly and moved lengthwise over a boom which carries a pipe clamp and internal welder at its end. A second section of pipe is then moved onto the pipe support roller assembly and moved lengthwise into engagement with the first pipe section. After the first and second pipe sections have been properly aligned and the clamps expanded to hold the pipe sections in welding positions, the pipe sections are rotated simultaneously while both internal and external welds are made simultaneously. A cap weld may also be formed with the pipes clamped as described, or the pipes may be moved to another support roller assembly and the cap weld made while the connected pipe sections are on the second support roller assembly. The methods and apparatus disclosed result in considerable savings as to both the cost of equipment and operating costs.

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

Abstract: 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: Track apparatus, consisting of a circular track adapted to be affixed end-to-end around a pipe, usually adjacent an end thereof, to support a carriage apparatus for travel about the pipe, welding equipment, or the like, being mounted on the carriage apparatus for use in welding the pipe to another pipe abutted end-to-end therewith, or for other similar purposes. The track is supported by circularly spaced crossbars each provided with inwardly projecting spring biased pins upon which the crossbars are supported. A latch device for affixing the ends of the track together is provided. The track has frictional engagement means around its outwardly facing surface for engagement by drive wheels of the carriage apparatus.

Abstract: Rotary internal pipe clamp apparatus for use in welding pipes together end to end, said apparatus having a first set of circularly spaced pipe engagement elements for disposition within the end of one section of pipe, and having a second set of circularly spaced pipe engagement elements for disposition in the end of a second length of pipe abutted end to end with the first length of pipe. Each set of circularly spaced pipe engagement elements is expanded and retracted by rotation of a circular disc to which said pipe engagment elements are linked by toggle elements. In addition, the apparatus includes a welding back up assembly which is expandable and retractable simultaneously with the second set of pipe engagement elements. The welding back up assembly includes plural peripheral bands or strips which are supplemented by shorter peripheral bands or strips which separately retract and expand.

Abstract: Rotary internal pipe bending mandrel, wherein sets of pipe engagement elements at opposite sides of the pipe interior are actuated by generally radially disposed toggle elements which expand and retract the pipe engagement elements by rotations of a central assembly. The elements which support the pipe engagement elements are disposed in circularly spaced groups which are axially spaced along the direction of the pipe, and each group is separately expanded by a separate fluid motor assembly. The apparatus has improved the load bearing characteristics because it has positive end engagements of the toggles, whereby the pins or shafts on which the toggles are pivotally mounted are not excessively strained.

Abstract: Method and apparatus for bending coated pipe including heating a specific area of the pipe coating by resistance heating to prevent damage at all areas of the pipe coating during bending of the pipe. The pipe bending equipment includes an upper bending die, and a lower pin up shoe and a lower strongback. The strongback has resistance heating means in a recess which is positioned over a specific area of the upper surface of the strongback, for heating the pipe coating prior to bending of the pipe. By heating of a relatively small specific area of the pipe coating, damage to the entire area of the coating is avoided.

Abstract: Apparatus for finishing the ends of pipes, particularly for shaping the ends of pipes preparatory to welding the pipes together end-to-end, wherein the cutting tool or tools employed to finish the pipe end are urged against the pipe end hydraulically, and wherein the hydraulic fluid is pressured by a hydraulic pump which operates in response to rotation of the pipe end finishing apparatus. A variety of cutting tools may be employed, singly or in combination, for finishing the butt end of the pipe in flat, beveled, or stepped condition.

Abstract: Traveling support apparatus for supporting welding device or other apparatus for peripheral travel about a pipe. The support apparatus utilizes endless belts disposed around paired wheels at opposite sides of the apparatus to propel the apparatus along a track. The endless belts are pivotally supported for equal pressure engagements with the path along which the support apparatus travels. The support apparatus engages opposite sides of a track in the form of a strip or band spacedly surrounding a pipe to support a frame which is held firmly against movements toward or away from the track so that the supported apparatus is reliably held in position with relation to the pipe.

Abstract: Pipe bending mandrel wherein oppositely disposed pipe wall engaging elements are connected to a drive unit at one end by toggle elements permitting inward and outward movements of the pipe wall engaging elements, and wherein said pipe wall engaging elements are connected to a longitudinal axial shaft of the drive unit by plural axially spaced toggle elements which move the pipe wall engaging elements inwardly or outwardly upon reciprocating movements of the shaft in opposite directions.

Abstract: Internal mandrel for use in bending the ends of pipes, wherein a hydraulic cylinder actuates a system of levers and toggles to apply force across the interior of an end of a pipe in the direction in which the pipe is to be bent to prevent distortion and collapse of the pipe during bending adjacent to its ends.