플라즈마 스트림 이론에 의한 C-형 스트립 TIG 클래딩에서 광폭 비드를 위한 공정 연구

Abstract

As the importance of offshore and chemical plant industry has emerged, the demand for special metal products to improve corrosion and heat resistance increased, and the cladding technology has risen as a major concern. In current small-diameter pipe cladding, TIG welding of low productivity is mainly used, and a study on a material in the form of a flat type strip which increase a productivity by 3 folds in existing low productivity wire shape has been proceeded, and it was thereafter developed as C-type of concaved shape by applying the plasma stream theory to a flat type strip. In this study, a productivity is examined by comparing the deposition rates of a flat type strip and C-type strip, and a method of obtaining broad beads to solvea high bead height problem caused by the increase of deposition cross-sectional area due to the low welding speed in a high deposition rate, which is a problem of C-type strip, was studied through a change of process condition. As a result, when a weaving width was increased, a bead width was increased, and an increase of bead width when dwell time was applied was confirmed. In addition, a tendency of bead width increase was appeared when the welding current is increased, and a phenomenon of bead width increase was also observed when an experiment was done with increased amount of He in shielding gas. Through these broad bead experiments above, a method of solving a high bead height problem of CS-TIG was confirmed, and it is considered to be one step forward advance in a practical use of CS-TIG.