Improvements in weld backing members and an improved method of forming welded jointsin metallic members or between metallic members

摘要

993,755. Welding by fusion. STEWARTS & LLOYDS Ltd. Nov. 18, 1963 [Feb. 13, 1963; Dec. 5, 1962], Nos. 45949/62 and 5858/63. Heading B3R. In a method of welding, the seam is backed by a member 10, e.g., mild steel, spray coated on its weld engaging surface with a refractory oxide, e.g. alumina or zirconia. The backing may be in the form of a strip for a U-seam or a seam shaped as shown in Fig. 3, a ring for butt welding tubes or for welding a branch 22, Fig. 6, to a main pipe 23, a shaped bar for welding one side of a double V-seam, Fig. 5, or for making an external joint between perpendicular plates 26, 27, Fig. 7. The ring may be split and secured in place by expandable means. In welding strip 34, Fig. 9, to form a helically jointed tube the backing may be a strip fed from a reel 32 or an endless strip and held in place by a roller device 35. Alternatively the backing may be an oxide coated roller. The refractory oxide is applied by a flame spraying process as described in Specification 745,257.