FORFARANDE FOR BAGSVETSNING MED ICKE-SMELTANDE ELEKTROD I SKYDDSGASATMOSFER

摘要

The inert gas arc welding process employing a non-consumable electrode consists of the following steps. Before the welding process the edges (5, 6) of a butt joint (1) are machined to produce a truncated surface (7) and the electrode is lowered the whole depth (h) of the weld seam. The truncated surface (7) is then melted over the whole thickness ( delta o) in the first pass and a weld root (8) of the first layer (9) is formed. With each successive pass the energy of the arc (4) per unit length is changed relative to the preceding pass. When a depth of h SIMILAR (0.3 to 0.4) delta of the weld seam is reached and its width is B SIMILAR (1.0 to 1.3)h, the electrode (2) is removed from the region of the weld seam and is arranged above the surface of the butt joint (1) in the region of the joint (3). Furthermore, the energy of the arc (4) per unit length is discontinuously raised compared to the preceding pass and the edges (5b, 6b) of the butt joint (1) are completely melted, with the formation of a layer (13) on the surface of the joint, whereupon the energy of the arc (4) per unit length is changed from pass to pass.