GB374339A - Improvements in and relating to methods of and apparatus for arc welding - Google Patents

Abstract

374,339. Uniting by fusion. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, London.-(Assignees of Brophy, G. R. ; 19, Dean Street, Schenectady, New York, U.S.A.) Sept. 3, 1931, No. 24781. Convention date, Sept. 4, 1930. [Class 83 (iv).] In metallic or carbon are welding the parts are enclosed in a chamber having a wall of fluxing material, which is partly consumed by the heat of the arc to form a protective medium over the fused metal. An arched chamber 3 may be formed by a folded sheet or several sheets of paper, the edges of which are secured by clamps 4, 5, 6 to the work parts 1, 2, one end of the chamber being preferably closed. The parts may rest on a table or bed 7 having a chill insert 11. The paper is in part burnt by the heat of the arc or by contact with the electrode 9 to furnish an atmosphere of carbon monoxide and carbon dioxide. The paper may be loaded with kaolin or clay or saturated with sodium or potassium silicate so that it does not burn readily and also deposits flux on the weld. The chamber may also consist of asbestos, impregnated cloth, or thin walled glass, in the form of an inverted slitted troughlike member &c., or may consist of a frame with a covering of paper secured thereto. The top of the member may be slit or perforated, or may be of reduced section so that the electrode may pass through it. A paper shield may be slit by charring thereof during the progress of the welding operation. Any carbon precipitated on the fused metal reduces oxygen dissolved in the metal with the liberation of heat and also increases the carbon content thereof.