SMED: Single Minute Exchange of Dies

These modern times of rapidly increasing diversity and smaller batch sizes, setup time reduction is of crucial importance for the profitability of many companies. For example, bottling industries sometimes spend more than 20% of their planned production time on changeovers. Fortunately, these setup and changeover times can be reduced significantly when the SMED system is applied. The SMED system has a proven track record in many types of industries. You may wonder: "Is it magic, or something everybody can apply?". Fortunately everybody can apply the SMED system to reduce their setup times, and there is nothing magic about it!

Single Minute Exchange of Dies (SMED) is the approach to reduce output and quality losses due to changeovers. The method has been developed in Japan by Shigeo Shingo, and has proven its effectiveness in many companies by reducing changeover times from hours to minutes. "The flow must go on", was Shigeo's reaction when he witnessed change over times of more than 1 hour. Based on his huge experience, he developed a method to analyse the changeover process, enabling local personnel to find out themselves why the change over took so long, and how this time can be reduced. In many cases, change over and setup times can be reduced to less then ten minutes, so the change over time can be expressed with one single digit, and is therefore called "Single Minute Exchange of Dies".

This analysis consists of the following 4 phases:
1. mixed phase
2. separated phase
3. transferred phase
4. improved phase

The method's strength is the systematic approach to analyse what is actually done and how time is spent during the changeover activity. Through the analysis, a better understanding is gained on how to do certain activities, when the line is running. Also it is determined, what can be done to reduce the "fine tuning" activities after the actual changeover.

Changeover losses is one of the 6 big losses that have been defined within the TPM method.