A Plan-Do-Check-Act Based Process Improvement Intervention for Quality Improvement

Waste from raw materials has a direct influence on the final price of a product. However, since waste has no added value to products, customers are unwilling to pay for it. Reducing waste along the production process and supply chain allows companies to decrease costs and remain competitive in product prices. This research is conducted in a medical device manufacturing company located in Tijuana (Mexico). The company found a negative variation in part number 9540, a metallic foil used for hot stamping. During inventory cycle counts, the company found that they were purchasing rawer material than necessary due to a 50% of waste generated along the production process. We implemented two process improvement methodologies, namely Practical Process Improvement (PPI) and the Plan-Do-Check-Act model, to eliminate 100% of the raw material waste, specifically regarding the foil's waste. The improvement project comprised two phases: a) adjusting the parameters of the hot foil stamping machine and b) replacing the hot foil stamping machine with a pad printing machine. In our research, the PPI methodology is presented in 8 detailed stages as a simple problem-solving method, in contrast with five stages reported in other documented cases. This case study presents how a company can apply continuous improvement programs and its managerial implications, even without having a structured and defined systems for quality, such as Six Sigma or Lean Manufacturing implemented. After the two implementation phases, the improvement project led to economic savings of $\$ $ 165,000 in a year.