Abstract
It is well known that angular distortion in conventional welding has been predicted by heat input parameter proposed by Satoh and Terasaki, however, it is also well known that angular distortion in new welding process such as Tandem Arc welding has not always been predicted by conventional heat input parameter. Thus, welding distortion characteristics in multiple-heat-source welding have been investigated thermal conductivity theory and numerical simulation. First, an influence factor concerning angular distortion in multiple-heat-source welding has been extracted by thermal conductivity theory. As the result, the following factors are given as an influence factor for angular distortion in multiple-heat-source welding; heat input parameter, distance between two heat sources, heat input ratio, and welding speed. Based on them, the effect on angular distortion in multiple-heat-source welding has been evaluated by numerical simulation. In multiple-heat-source welding, angular distortion is possible to differ greatly by influence of distance between two heat sources or heat input ratio, even though heat input given to weld joint is equal. That is, multiple heat sources are appropriately arranged, then, angular distortion is expected to be able to be reduced effectively.
