Single Minute Exchange of Die (SMED) is a cornerstone of lean manufacturing and can help to reduce setup time and improve productivity enabling smaller batch sizes to be produced whilst reducing lead time.

The method developed in Japan by Shigeo Shingo, and has proven its effectiveness in many companies by reducing changeover times from hours to minutes. The successful implementation of SMED and quick changeover is the key to a competitive advantage for any manufacturer that produces, prepares, processes or packages a variety of products on a single machine, line or cell. SMED and quick changeover allows manufacturers to keep less inventory while supporting customer demand for products with even slight variations. SMED has a lot of hidden benefits that range from reducing WIP to faster ROI of capital equipment through better utilization

Effective SMED programs identify and separate the changeover process into key operations –

External setup involves operations that can be done while the machine is running and before the changeover process begins. Internal setup are those that must take place when the equipment is stopped. Aside from that, there may also be non-essential operations.