ANALISIS KUALITAS HASIL PENGELASAN MENGGUNAKAN METODE SIX SIGMA GUNA MENGURANGI WELD DEFECT

Abstract

Welding is a method used to join metals. If a weld is of poor quality, it can become a weak point in a structure or component, potentially leading to structural failure or serious accidents. Quality inspection is necessary to ensure that the welds meet safety standards and can support the expected loads. However, welding often results in imperfections or defects that require repair. Therefore, the author conducted an analysis of the welding results using the Six Sigma method to identify common defects and assess the performance of the welding process, with the aim of proposing corrective actions. The goal of these improvements is to reduce the number of weld defects and achieve a higher sigma level. The research identified three common types of defects in water wall tube welding: porosity, cluster porosity, and worm holes. The baseline DPMO (Defects Per Million Opportunities) value found was 16,116.04, with an average sigma level of 3.73, indicating 16,116.04 defects per one million opportunities, which is on par with the average industry standard in Indonesia. Consequently, the author recommends implementing improvements using the PDCA (Plan-Do-Check-Act) method to increase the sigma level and reduce the DPMO value by 61.47%, resulting in an average of 1 defect per joint per day. These improvements also have the potential to save costs, enhance time efficiency, and improve workplace safety and health.