A waste relationship model and center point tracking metric for lean manufacturing systems

Abstract

Lean manufacturing is about eliminating waste, which requires the creation of waste metrics that are tracked in order to create the conditions for its elimination. In this article, metrics used to monitor the seven traditional non-value adding wastes types of overproduction, defects, transportation, waiting, inventory, motion, and processing are explored and a “center point metric pair” is proposed that can give systematic insight into system waste performance and trade-offs. For example, lower work-in-process levels (inventory waste) may require more replenishment (transportation waste) in order to maintain production. A waste relationship model is proposed that can be used to derive the relationship between different wastes in a Pareto-optimal waste-dependent lean system. The trade-off relationships are statistically verified using simulation experiments across different system configurations, complexities, and planning scenarios.

Keywords:

• Lean manufacturing
• waste relationships
• performance metrics
• trade-offs
• decision making

Acknowledgement

The authors thank the support of the Canadian Auto21 Network Centres of Excellence and the University of Calgary.