Abstract
According to the rule of high pressure gas in Japan, it is limited strictly to generate the weld defects in weld zone. In this report, on high pressure gas piping of aluminium, an automatic all position welding process without blowhole is investigated. The following results were obtained in this study.
It was found that the quality of weld zone by using He-DCEN·TIG is better than that of Ar-AC·TIG. In He-DCEN·TIG, shielding gas flow conditions influence on generating blowhole, but back shielding gas has no effect on it. In brushing treatment of root face, many weld defects such as aluminium oxide inclusion are produced. On the other hand, in the case of mechanical treatment that the root face becomes fiine smooth, occurrence of these defects decreases.
