Solder Lead Waste Reduction of a Selected Mobile Phone Factory: A Six Sigma DMAIC Approach

Abstract

Six Sigma is an explicit statistical method of reducing variability and improving processes. Our research works with internal customers within the assembly lines. This study aims to identify and analyze the VOC of internal customers and show improvement based on the VOC. The Six Sigma DMAIC method was followed to conduct this research. Six mobile phone assembly lines were selected to collect wastage data for two months after identifying the problem. Collected data were analyzed in MS Excel, and this analysis showed that the wastage rates were 91.38% in July 2024 and 80.67% in August 2024. The average waste rate was 0.44 g/unit and 0.41 g/unit in July 2024 and August 2024. The root cause analysis, and cause and effect diagram illustrated that most of the reasons behind wastages were related to soldering operators. An awareness and training session was conducted. We collected data for the next month and found the wastage was reduced to 69.27% in September 2024, which is a 24.5% reduction considering August 2024 as the base. The average waste rate was reduced to 0.28 g/unit. The effectiveness of following the Six Sigma method to solve quality or wastage issues is evident hereafter accomplishing this research.