| 摘要 |
1,189,741. Welding by fusion. CRC-CROSE INTERNATIONAL Inc. 12 Jan., 1968 [12 Jan., 1967], No. 1782/68. Heading B3R. Apparatus for internally welding pipes endto-end comprises a clamp for internally gripping and shaping each of the pipe ends to be welded and one or more welding heads mounted on the clamp to move along the joint. The apparatus is movable along the inside of a pipe by a trolley 49 having wheels 50 driven by an air motor. Universal couplings 70, 72 connect the trolley 49 to the clamping and welding device 20 having supporting wheels 45 and a carriage carrying an air bottle 60 which if desired can be filled by a tube extending along the pipe. The device 20 has two sets of clamping members 22 radially movable by toggle links 115 actuated pneumatically under sufficient pressure to ensure that a distorted pipe end is deformed to its proper circular section while welding is performed. A piston 74 may be actuated to free a ball joint 79 to enable the members 22, each of which may carry a pair of pipe engaging rollers, to be aligned at the correct spacing from the pipe end by gauging blocks pivotally mounted on the members 22 or by independent magnetic blocks positioned on the pipe. The device 20 drivingly mounts a ring 30 to which are detachably secured a number e.g. four, inert gas shielded consumable electrode arcwelding heads 32 each having a U-shaped frame 160 supporting an electrode reel 165, feed motor 166 and welding nozzle 184. The cables and conduits 38 for the welding heads 32 are brought to a common point 37 and supplied through a cable 35 extending along the pipe. Welding is effected by movement of the ring 30 through a little over 90 degrees so that two heads 32 make a downward weld completing one side of the seam. Subsequently the other two heads 32 are used to weld the other side also downwardly. The gauging blocks may be retractably mounted on the clamping and welding device 20. In a modification, the ring 30 is internally toothed and forms part of a driven epicyclic gearing unit. In a further modification, the welding heads 585, Fig. 10A, are separate motorized trolleys running in a recess 500 in the clamping device and having rollers 522 engaging grooves in the recess 500 and a driven pinion engaging a rack on the base of the recess. The rollers 522 on one side are movable inwardly to permit removal of the welding trolley. In a further modification the internal clamps when engaging the pipes can be drawn together by a pneumatic ram to bring the pipe ends into firm abutment. |
