Patent GB-1107953-A (GB)
Title: Method and apparatus for welding pipe sections together
Inventor: HORNING WILLIAM ANDREW
IPC: B23K9/028
Filed: 1965-08-31
Abstract: 1,107,953. Welding by pressure. R. H. DYER, and L. W. BURNETT. 31 Aug., 1965 [14 Sept., 1964], No. 37211/65. Heading B3R. In welding two metal pipes together along adjacent curved ends in contact with welding material a welding member in contact with the welding material is moved relatively to the pipes and current is passed through the welding member and welding material. An apparatus for welding end-to-end pipes 2, 3, Fig. 10, having bevelled edges with a ring 7 of welding material, having projections 7<1>, located in the groove formed by the edges, comprises a frame 8, Fig. 4, having a structure 9 supported by a crane 10. Semi-circular hollow jaw members 11, 12 are pivoted at 23 to the frame 8 and hydraulic cylinders 25, 26 are connected between the jaws and the frame to pivot the jaws to close about the pipe ends. Locating pins 30 on the frame engage sockets 36, 37 secured to the pipes and screws 32 on the jaws engage the pipes. Semicircular guide members 54, Fig. 2, are secured to the inner walls of the jaws to provide a pair of spaced closed circular tracks about the pipes when the jaws are closed and first and second semi-circular gear sections 57, 58 have wheels 59 rotatably mounted thereon and engaged in the tracks. The gear sections abut when the jaws are closed and form a gear cage 60 driven about the pipes by a pinion 96 on an hydraulic motor 95. A carrier 61 is secured to the section 57 and carries in bearing blocks, arranged for radial movement towards and away from the pipes, a welding roller 66. An hydraulic cylinder 75 applies pressure to the welding roller 66 via levers 71 and to roller bearings 78 extending from levers 76 to engage electrical contact wobble rings 80, 81. Two pairs of semicircular wobble rings 80, 81 are resiliently mounted on the guide members 54 by springs 82 to engage the pipes on opposite sides of the welding material 7. A pair of semi-circular slip-ring sections 85 located in the jaws are connected at 87 to transformers mounted on the jaws so that when the jaws are closed the sections 85 form a slip-ring engaged by brushes 91 on the carrier. A reciprocating hammer 93 is provided on the carrier to act on the ring 7 immediately after welding. Further transformers supported on the jaws are connected to the wobble rings. The transformer secondaries are connected in threephase relation. An internal mandrel (123), Fig. 5 (not shown), has segments (124) in contact with the pipes to align and draw the pipes together and provides a back-up support during welding. In operation the pipes are cleaned, the welding wire 7 is placed over one edge and the pipes are drawn together by the internal mandrel. The spacer member to provide the sockets 36, 37 is arranged on the pipes and the jaws are opened to locate them on the pipes and then are closed. The welding roller is urged against the ring 7 and current flow started and when sufficient heat is developed the carriage is caused to travel about the pipes. The first weld may be a high-speed tack weld followed by a low-speed weld pass-the hammer 93 being operated during welding.