GB1426227A - Method and apparatus for welding - Google Patents

Abstract

1426227 Welding by pressure TRANTER MFG Inc 6 Jan 1973 [3 April 1973] 26975/73 Heading B3R In welding a workpiece comprising a pair of components having flat surfaces in face to face contact, relative movement is effected between the workpiece and a welding device, the relative movement including a series of movements performed along parallel paths and further movements performed along paths interconnecting the parallel paths, the welding device being operated during the movements along the parallel paths so as to produce rows of parallel weld lines, some being continuous while others are discontinuous. In an embodiment a pair of rectangular plates 12 are welded together face to face with a parallel pair of continuous resistance seam welds 14 along the margins, continuous resistance seam welds 14<SP>11</SP> inwardly from the margins and rows of discontinuous welds 15 the welded plates being subsequently subjected to internal hydraulic expansion to produce a heat exchanger plate. The welding is effected in an apparatus comprising a table 17 having a notch 18 to accommodate a resistance roller seam welder 20, a plate support carriage 30 being slidable on guide rods 32 and movable by an endless belt system. The rollers 21, 21<SP>1</SP> of the welder are rotated by knurled rollers 22 engaging the rollers and the upper roller 21 is carried on the piston of a pneumatic cylinder 24. The housing 45 of the carriage 30 carries screwed rods 46, transverse to the direction of travel of the carriage, which are connected to a bar 48 guided by rods 49 slidable in the housing 45 and clamps 51, 52, 53, pneumatically operated, are mounted on the bar 48 for carrying the plates to be welded. A motor 44 drives a pulley 42 which is belt connected with a pulley 40 having an overrunning clutch and mounted on a shaft 39 driven from a gear-box 79, another pulley 38 on the shaft 39 driving the endless belt 35 connected to the carriage 30. A motor 55 on the carriage causes transverse movements of the bar 48 and shafts 92, 93 driven from the gearbox 79 drive the knurled electrode roller driving rollers 22. An automated card controlled computer unit 58 controls the major portion of the operation of the apparatus. In operation the plates 12 are clamped to the bar 48 by devices 51, 52, 53, a push button 87 is pressed and the motor 44 causes the carriage to move to the left to take up a weld start position in contact with an automatic stop 56. The upper roller electrode 21 is lowered when another button 68 is pressed and when button 71 is pressed the carriage is moved to the right by a main motor 75 operating through gear-box 79 under the control of a card in the unit 58 and lines of continuous and discontinuous welds are formed. The plates are then turned through 180 degrees and the process repeated. The welded plates are then unclamped from bar 48 and are turned through 90 degrees and clampedto a guide. 57 latched to the carriage 30 for movement therewith. Welding in lines at 90 degrees to those previously made is effected on the plates.