A methodology for assessing most vulnerable welding procedure specifications and imperfection factors

Abstract

The determination of appropriate welding conditions are significantly challenging as welding characteristics are inherently non-linear and complex. Many researchers have developed algorithms and/or mathematical models to control welding parameters achieving desired weld bead geometry. The difficulty in representing the exact relationship between welding conditions and weld defects in terms of algorithms and/or mathematical models jeopardises the level of weld quality. The unstable welding conditions induce unacceptable weld beads, resulting in poor mechanical and metallurgical properties at welded joints leading to defective welds. This manuscript suggests a methodology to assess the most vulnerable welding procedure specifications (WPSs) and imperfection factors that contribute to the majority of defective welds annually. Based on the identified WPSs, it also suggests a methodology to recognise the most critical imperfection groups and the related imperfection sub-groups as specified in NS-EN ISO 6520-1. This enables the formulation of optimum cost vs. quality improvement solutions for technicians, engineers and managers.