Lowering Customer Claim &; Ng Ratio on Jack Bracket Part Using Lean Six Sigma-DMAIC Method at PT. XYZ

PT. XYZ is a manufacturing company that produces Sub Assembly products for two-wheeled and four-wheeled vehicles. Broadly speaking, the stages of the Jack Bracket production process consist of five processes, namely  the sharing stage in the Raw Material Line, the Stamping process  in the Small Press Line,  the Spot Welding Stage in the Welding Assy Line  and the Checking Stage   in the Final Inspection Line. This research was conducted at  Line Assy Welding where  the Line produces Jack Bracket parts and Line Final Inspection. Based on  NG Outflow &; NG Ratio data  in the period July to December 2023, 57 pcs of spot defects were  obtained and the number of internal process defects was 32,325 PPM which is equivalent to sigma level 3.3. After applying the six  sigma method, the number of NG Customer Claims is nil (0 pcs) and the level of product defects can be reduced to 7,500 PPM which is equivalent to sigma level 4.