Analysis of Welding Start Part Defects According to the Shape of the Electrode Tip during Shield Metal Arc Welding

Abstract

The main device material used in power generation facilities is high-tension steel, which has a significant impact on weldability and longevity. Therefore, high-base flux and high-base low-hydrogen welding rods are used to reduce hydrogen content.<br/> In this study, welding equipment, polarity, and prior technology were reviewed to implement rapid arc stabilization using AWS E7016 low hydrogen welding rods based on user needs for power generation facilities and global standards, and various shape designs of welding rod fleets were attempted. This increases the arc start current density to induce metal transfer mode using the Hollow Electrode effect and the increase in current value at ignition, thereby implementing initial arc safety and optimal welding atmosphere to solve fatal early welding defects such as pores, slag mix, and fusion.