Mix attainment improvement

Abstract

This Capstone Project was conducted at St. Jude Medical’s manufacturing plant in Caguas, Puerto Rico, focusing on improving the Mix Attainment metric, which measures the timely conversion of mechanical heart valve (MHV) production orders into finished goods. The project utilized the Define, Measure, Analyze, Improve, and Control (DMAIC) methodology. During the Define phase, key project elements such as the project charter, SIPOC diagram, VOC, and CTQ diagrams were developed to outline objectives and deliverables. The Measure phase established a baseline, revealing a year-to-date Mix Attainment rate of 56% as of June, with the Master MHV Family chosen as the pilot group due to its 63.82% share of production. The Analyze phase identified non-quality-related issues, such as failure to follow FIFO principles, process inefficiencies, and excess inventory, as primary contributors to late work orders, accounting for 25% of delays in Pareto analysis. Quality-related issues were excluded as they were being addressed by the Quality Department. In the Improve phase, the team recommended process changes, including kitting verifications in the Carbon Prep area to eliminate backtracking, reducing release inventory from two days to one shift, and streamlining FIFO and rework processes. These improvements reduced Lead Time by 49.81%, from 5.36 to 2.69 days, and yielded estimated savings of $60,475.88 with a payback period of just 46 days. To sustain improvements in the Control phase, procedures such as kanban audits and weekly rework reporting were implemented. If fully adopted, these measures can enable St. Jude to achieve a 100% Mix Attainment rate, even with reworks. This project demonstrates the effectiveness of DMAIC in optimizing manufacturing processes and achieving substantial cost savings while enhancing operational efficiency.