拡散性水素低減トーチのガス流体解析

抄録

This study aims to reduce diffusible hydrogen in GMA and FCA welding. For this purpose, a novel welding torch with a dual structural gas nozzle, which enables to suction hydrogen source gas evaporated from a wire, has been developed. In order to improve the suction efficiency of this evaporated gas, precise control of the suction gas flow is indispensable. In this paper, as the first step of research, ignoring the evaporation of hydrogen source gas from the wire, only influence of the suction nozzle structure and torch operating condition on the suction gas flow pattern was investigated through numerical simulation. As a result, it is suggested to be especially effective in reducing diffusible hydrogen to extend the suction nozzle length within a range not disturbing the arc, or to design a nozzle structure that provides an equivalent effect with the extension of suction nozzle length.