Design of Fixture for Welding

Abstract

Defects commonly found in welding include distortion, overlapping, warping, and misalignment. Welders probably observe more frequent problems as such if lacking proper fixturing devices. Existing fixture designs are tedious to use, and they could induce even more defects. In this study, four design alternatives of a welding fixture were initially conceptualized from a survey of 25 experienced welders before the best one was selected based on reliability, rigidity, and ease of use. The design was made of SS400 steel because of its exceptional mechanical and thermal properties. A structural analysis was performed using the finite element method to evaluate the strength and stability of the design while in use. Experimental results revealed that this fixturing device could withstand forces exerted vertically from screw clamping. It could also tolerate high temperature from a welding arc and restrain the workpiece as deformed by the heat. This novel design will minimize set-up time, chances of defect formation, and a need for post-welding quality improvement.