GB1151348A - Method of Forming a Weld under Pressure between adjacent Metal Portions - Google Patents

Abstract

1,151,348. Welding by pressure. AMERICAN MACHINE & FOUNDRY CO. 9 Sept., 1966 [21 April, 1966; 5 May, 1966], No. 40453/66. Addition to 1,150,770. Heading B3R. In welding two metal portions, the portions are held fixed with respect to each other and with faces thereof extending longitudinally in parallel directions, an elongated metal filler member is positioned in contact with the portions in the region of the faces, high frequency current is caused to flow in the filler member and portions to soften them and the filler member and portions are subjected directly to a mashing force to weld the portions and filler member together. Two sheet metal strips 25, 26, Fig. 1, which may be the end portions of large coils of strip are clamped in abutting relation by jaws 29, 29<SP>1</SP>, 30, 30<SP>1</SP> over a back-up bar 28, high-frequency current from a source 31 is supplied by contacts 32, 33 at or adjacent the seam line and a metal strip 34 or foil preferably of the same metal as the strips 25, 26 is fed to rest on the seam line to be engaged by the contacts 32, 33. A pressure roll 35 mounted on a frame carrying the contacts is moved along the seam line or the workpieces are moved relative to the roll 35, which may be used as a contact, to compress the foil strip against the seam line. The strip may be forced down into the surface of the strips 25, 26 as at 34<SP>1</SP>, Fig. 3. Conductive tabs 38, 39 may be employed to ensure that the weld extends to the ends of the seam line. The foil strip may be supported beneath the seam line, i.e. remote from the roll 35 or the filler may be in the form of wire fed beneath the roller 35 or foil or wire may be applied to both the upper and lower surface. To prevent overheating of the filler wire it may be fed through an insulated tubing. Flat or concavo-convex strips or the edges of a length of tubing having depending lips which are abutted and a length of filler wire is fed to the shallow groove formed by the abutting lips which are held together by clamps or rolls. In welding a workpiece 61, Fig. 14, on edge to a workpiece 62, a triangular filler strip 63 is fed into the corner between the workpieces and after being heated by the contact devices the assembly is pressed to a roll 64 reacting against a roll 65. Two such strips may be fed into the corners above and below workpiece 61 and the strip may be of circular section. In welding bevelled edges 71, 72, Fig. 18, of workpieces 73, 74, a filler strip 70 of trapezoidal cross-section is fed to be welded between the spaced edges 71, 72. Such welds may be around pipes, tanks or submarine hulls. In a further embodiment a filler piece of inverted T-section is fed between parallel edges and concave pressure rolls may be used to shape the ends of the filler piece. Induction heating may be used and ferrous metal or aluminium and copper may be welded. The filler may be coated with flux, e.g. borax.