Patent GB-390256-A (GB)
Title: Improvements in electrodes or welding rods for use in electric arc welding
IPC: B23K35/04
Filed: 1931-12-08
Abstract: 390,256. Uniting by fusion. QUASIARC CO., Ltd. and STROHMENGER, A. P., 15, Grosvenor Gardens, London. Dec. 8, 1931, No. 34021. [Class 83 (iv).] A welding electrode or rod is made by first applying to a metal core by a painting or dipping process a uniform covering of paste giving a substantial body of slag when the electrode is fused and then wrapping around the paste a flux coating of mineral fibres, such as asbestos, in the form of a yarn or sliver so as to form a separate layer binding the paste in position. The core 2 which has previously been straightened, may be led through a heater 3 and a ring 1 dipping in a paste container 4, the core being rotated during its passage through the apparatus. A series of containers and rings may be used for thin pastes. The paste may in another form be sprayed on a rotating core. In a further form the core may be fed by rolls 7 through a straightener 8, and cutter 9 and the cut lengths automatically gripped in turn by spring or magnetic clamps 10 on an endless band 11 which carries them through a tank 13 containing paste and then through a drying oven 14. The coated wires are automatically detached at 15 from the conveyer. A series of paste containers alternating with dryers may be used. After the core has been coated with paste the coating of mineral fibres is then applied, which may subsequently be impregnated with alkaline salts &c. to lower the fusion temperature of the asbestos. If the asbestos is to be applied directly after the paste, a stiff or viscous paste is used, but if a more fluid paste is used, it may be set by heat or chemical action with reagents such as lime and sodium silicate or both, prior to application of the asbestos. The yarn may be soft so as to spread laterally during the finishing operation. A number of plies of yarn disposed side by side may be applied or two or more overlapped slivers. The yarn or sliver may include mixtures of blue asbestos with nitrated cellulose, together with potassium dichromate as described in Specification 363,815. A thin layer of asbestos paper or cellulose paper may be applied to the paste before winding on the yarn so as to smooth out inequalities in the paste surface. The paste may contain ingredients chemically equivalent to blue asbestos, such as ferrous silicate, together with ferromanganese, ferro-vanadium, ferro-titanium, &c., and a binder of sodium silicate &c. A steel electrode containing 1 per cent of carbon, 0.1 per cent of silicon, 0À8 per cent of manganese, and 1 À5 per cent of chromium may be provided with a paste consisting of 45 per cent of Fe2O3' 13 per cent of Mn, 20 per cent of Ca(HO)2, 2 per cent of (C6H10O5)n, in the form of soluble starch, 5 per cent of Na2SiO3, 5 per cent of Na2CO3, 5 per cent of Cr, and 5 per cent of C. An electrode for depositing stainless steel may have a steel core containing 18 per cent of chromium, 8 per cent of nickel, 0À1 per cent of carbon, 0À5 per cent of silicon, and 0À5 per cent of manganese with a paste consisting of 25 per cent of Fe2O3' 18 per cent of Ca(HO)2, 2 per cent of (C6H10O5) , 5 per cent of Na2SiO3, 5 per cent of Na2CO3, 10 per cent of Cr, 10 per cent of C, and 25 per cent of CaF2. Specification 197,196, [Class 83 (iv), Metals, Working], also is referred to.