Reducing Defects during Wrapping Process in Plastic Straw Manufacturing: A Six Sigma DMAIC Approach with FMEA Prioritization

Quality is a crucial element in maintaining competitiveness within the manufacturing industry, especially in high-demand and globally competitive sectors, such as the production of plastic straws. Consistently meeting quality standards is essential for ensuring customer satisfaction, minimizing waste, and improving production efficiency. Inconsistent quality can lead to increased production costs, loss of customer trust, and reduced market competitiveness. This study examines quality control in the plastic straw production process at PT. XYZ by using the Six Sigma approach, specifically applying the DMAIC method. The research addresses recurring quality issues in the form of product defects that exceed the company’s 1% maximum allowable reject rate, particularly in the wrapping process. In the Define phase, the wrapping process was identified as the Critical to Quality (CTQ) point contributing most significantly to overall defects. The Measure phase revealed a Defects Per Million Opportunities (DPMO) of 2,558.08 and an average sigma level of 4.3, showing a process with moderate capability. The Analyze phase used a Fishbone diagram to identify root causes of defects across five main factors: man, machine, method, material, and environment. The Improve phase applied Failure Mode and Effects Analysis (FMEA) to prioritize risks and suggest corrective actions based on their Risk Priority Number (RPN) values. The findings highlight that systematic analysis using Six Sigma tools effectively identifies critical quality problems and proposes targeted improvement strategies. Moreover, the results propose actionable recommendations focused on supplier quality, machine maintenance, operator training, and component reliability to address defects that occur during the wrapping process