Quality Control Analysis Using Six Sigma Method and Root Cause Analysis on 100ml Bottles at PT. XYZ Pandaan

This study investigates quality control of 100ml bottle products at PT. XYZ Pandaan using the Six Sigma methodology and Root Cause Analysis. The primary concern is a high defect rate, which negatively impacts production efficiency and product quality. Over a 30-day observation period, 9,810 sample units were examined. Five major defect types were identified: black spots, oil stains, uneven bottle mouths, folded mouths, and deformations. Pareto analysis revealed that black spots, uneven mouths, and folded mouths constituted over 80% of total defects. A P-chart analysis indicated an unstable process. The Defects Per Million Opportunities (DPMO) was 5,708, corresponding to a sigma level of 4.03. The process capability index was 1.34, suggesting the process is capable but requires refinement. RCA was employed to develop improvement strategies, including operator training, preventive maintenance, and stricter quality control. The proposed control plan includes SOP implementation, daily checklists, continuous training, and visual management tools.