Scrap and Rebuild and Overhaul Reduction

In manufacturing, scrap and rework add cost to finished products and affect delivery commitments. If companies understand the root causes of failures that result in scrap and rework, they can correct the problems.

This project used historic manufacturing data to analyze and identify the finished products and subassemblies causing the most scrap and rework.

The team identified the main drivers of rework and scrap using the 80/20 Pareto Principle, which states that for many outcomes, roughly 80% of consequences result from 20% of causes. The team employed MS Excel data analysis tools, including pivot tables and sorting. and constructed a complex three-level Pareto chart to identify the main components that cause rework across four different manufacturing cells. These levels break down to a specific component in the manufacturing where failures occur. They conducted a root cause analysis using Ishikawa Diagrams, also known as fishbone or cause-and-effect diagrams, along with the 5 Whys problem-solving technique, to distinguish potential causes of rework. The team’s analysis highlights specific areas that require improvement, facilitating production engineering efforts for root causes of rejections and pointing toward corrective actions.