Single minute exchange of die. This is the name given to a series of techniques developed by Dr. Shigeo Shingo (co-developer of Toyota Production System with Taiichi Ohno) that analyzes and seeks to reduce all the aspects of operator involvement in the setup and changeover of machines.
The simple steps of the SMED system are:
- Observe and document ALL setup and changeover activities,
- Separate the external steps from the internal steps,
- Convert internal steps to external steps,
- Streamline ALL external and internal steps.
Most production managers are quick to see the benefits of increased up-time and productivity from machines that have experienced the results of good setup reduction routines, however, the greatest benefit to quick changeover is the manufacturing flexibility and enhanced response time that allows the production of smaller lot, larger variety runs on the same machine.
This is another example of translation difficulties from Japanese into English. The intent of SMED was stated by Dr. Shingo as changeover within ten minutes, or single digit.