Single-Minute Exchange of Die – or “every single redundant minute can kill you” :) It is one of the most important methods of lean production. SMED - rapid conversion - provides a rapid and efficient way of converting a manufacturing process from running the current product to running the next product. Ideally the change-over and the start-up should take less than 10 minutes.


Can you achieve it?


Toyota boasts of this statistics:

- 85% of all change-overs last less than 100 seconds,

- 14% last less than 10 minutes,

- 1% last more than 10 minutes.


    Method SMED is actually very simple. If we do not take in consideration technical improvement of working conditions as such, then only by change of organisation of work we can save 30 up to 50% of the relevant time necessary for change-over.


Let´s make clear what actually change-over time means, let´s clarify what is the start and what the end point.  When considering ordinary mass production, then the change-over time is the time taken to stop production and start production of the same, or another, product. By other words change-over starts when the production cell produces the last product and ends when the first good product of the same or another type is produced in the same production cell.


This indicates that not only the time necessary for tool change, but all service and setup times count.