STRAIN RELIEVING DEVICE OF BUTT WELD ZONE OF PIPE

摘要

PURPOSE: To rapidly execute welding of the butt weld zone of pipes with good accuracy by winding a long body around the weld zone. ;CONSTITUTION: The long body 3 has plural cross arms 4 connected freely rotatably with the end parts each other by means of hinges 5 and rollers 6 disposed freely rotatably at the respective hinges 5. A hydraulic jack 7 exists between both ends of the long body 3. The long body 3 is wound around the peripheral surface of the butt weld zone 2 of the pipes and the rod of the hydraulic jack 7 is extended. The movement in the tightening direction of the cross arms 4 by the hydraulic jack 7 is smooth as the respective rollers 6 rotate. Averaged correcting pressures act at equal intervals corresponding to the spacings between the respective rollers 6 on the outer peripheral surfaces of the pipes 2a, 2b. The force acting on the butt weld zone 2 of the pipes heads toward the central direction of the pipes with the rollers 6 as fulcra. The strains in the butt weld zone 2 of the pipes are corrected and the joining accuracy at the respective ends of both pipes to be butted is extremely enhanced. The butt weld zone 2 of the pipes is tack welded at plural points between the adjacent strain correcting rollers 6 and 6. The strain relieving device 1 is thereafter removed from the butt weld zone 2 of the pipes and the weld zone is subjected to regular welding.;COPYRIGHT: (C)1995,JPO