GB866603A - Improvements in or relating to welding apparatus - Google Patents

Abstract

866,603. Welding by fusion. ROLLSROYCE Ltd. March 4, 1959 [May 1, 1958], No. 13984/58. Class 83 (4). A clamping device for use in butt-welding sheet metal workpieces consists of a backing bar and two spaced clamping devices arranged to move in straight lines towards the backing bar. An arc-welding machine which is doubleended to cater for cylindrical workpieces 72 of different size has at each end a fixed backing bean 13 having a copper insert on which the edges to be welded are located. Clamps having fixed frames 11 on supports 12 are provided with series of fingers 19 with copper tips 19a which clamp the edges to be welded against the backing beam 13. The fingers 19 of each clamp are connected to a bar slidable vertically on a key 20 under the action of inflatable hoses 21, 22. A channel-sectioned beam 18 in which the key 20 is secured is slidable horizontally in the frame 11 by inflatable hoses 24, 25, hose 25 acting on a member 40 connected by screws 40a to the beam 18. Inward horizontal movement of the clamp is limited by a spacing bar 26 of stepped construction which is adjustable by a pin 26d to present different thicknesses to projecting portions of the frame 11. The hoses are inflated with compressed air under the control of valves. Welding is effected by an argonshielded non-consumable electrode torch 16 with the aid of filler wire fed from a reel 17. The welding head is mounted on a carriage running on ribs on one of the frames 11. In a modification, the clamps have cylinders engaging fixed pistons within the beams 18 and the hoses 21, 22 are dispensed with.