GB910271A - Improvements in or relating to apparatus for welding tubes or electric cable sheaths - Google Patents

Abstract

910,271. Making tubes and cables; welding by fusion. PIRELLI-GENERAL CABLE WORKS Ltd. June 16, 1960 [June 26, 1959], No. 21984/59. Classes 83 (2) and 83 (4). In making a thin-walled tube or cable sheath a strip of metal is passed longitudinally in succession through forming means to bend the strip transversely and through closure means effecting in combination with the forming means, abutment of the strip edges at a predetermined position between the closure means and a subsequently encountered restraining member and the strip edges are welded together at the said position by electric arcwelding means. The gapped tube is fed from forming rolls 2, Fig. 2, through closure rolls 4 which bring the tube edges together beneath the welding torch 3 and the welded tube is then passed through an apertured restraining block 6. The rolls 4 are mounted on levers 7 the adjusted positions of which are fixed by screws 9. In a modification, a tubular sleeve is held within the tube where it passes through the closure rolls and under the torch and may be used when the tube forms a cable sheath, the cable passing through the sleeve. In a further modification, the closure means 19, Fig. 4, and the restraining member 6 are combined in a single structure formed with a cut-away portion 16, to expose the tube, in which portion the welding torch is located above the point of abutment of the tube edges. The tube may be elliptical in section.