Development of a Supporting System of Pass Design in Multi-pass Welding Based on GMAW Weld Pool Simulation

Abstract

The multi-pass welding process is an indispensable to build a large construction. An automated welding system by a welding robot is desired to realize a high-productive process. Normally, so many welding tests are carried out to determine the optimum welding condition. However, there are many disturbances in the manufacturing site, and the welding quality becomes worse even though the optimum condition is used. Therefore, to realize a high-productive automated welding system, a pass design system which can optimize and correct the welding condition depending on disturbances is required. In this study, a supporting system of pass design in multi-pass welding process is constructed by using numerical simulation of the weld pool.

In this study, the system is applied to the multi-pass groove welding in horizontal position. Weld pool simulation is carried out to obtain the relationship between the welding condition and shape of the weld bead, and make a database of the system. This system can show the optimum welding condition depending on the gap size between the base metals. In addition, the system can correct the welding condition pass by pass depending on the shape of the previous pass. Finally, this system is applied to the experiment and the weld region shows good quality so the gap can be filled without defect. Therefore, the system developed in this study can support to optimize and correct the welding condition depending on the disturbance.