SMED: how do you reduce changeover time in seven steps?
Short answer
SMED (Single-Minute Exchange of Die) is a method for reducing the changeover time of a machine or line. You film a changeover, separate the tasks that can be done during production (external) from those that require downtime (internal), convert as much internal work as possible to external and standardise the rest. Digital work instructions make sure every shift actually follows the new method.
Which seven steps do you follow?
Work with a small team of operators, a technician and a team leader. Use one changeover as the starting point for each step.
- 1Choose the changeover. Pick a changeover that happens often and causes a lot of downtime.
- 2Film and measure. Record a complete changeover and note the time for each task.
- 3Separate internal and external. Mark which tasks require downtime and which do not.
- 4Make internal external. Move staging, looking up and preparing to before the stop.
- 5Speed up what stays internal. Quick-release couplings, fixed stops and working in parallel.
- 6Standardise. Capture the best method as a digital work instruction.
- 7Measure and improve. Compare every changeover with the baseline and adjust.
What is the difference between internal and external tasks?
Internal tasks can only be done when the machine is stopped. External tasks can be done while the previous order is still running. The more you do externally, the shorter the downtime.
| Task | Now | After SMED |
|---|---|---|
| Staging format parts and tools | internal | external |
| Looking up settings | internal | external (in the instruction) |
| Changing format parts | internal | internal, with quick-release couplings |
| Checking the first product | internal | internal, with fixed checkpoints |
An example breakdown. Your own changeover determines which tasks can be external.
How do you sustain the new changeover time?
- Capture every step in a digital work instruction, with a photo or video of the correct execution.
- Make checks mandatory: a step only proceeds once the checkpoint is ticked off.
- Measure every changeover: time and start-up scrap per shift, so deviations become visible.
- Improve the instruction, not the people: operator feedback goes straight into the next version.
Frequently asked questions
That depends on how many tasks are internal today. Measure a few changeovers first; then you will see how much can move to external. That baseline is also the starting point of a pilot.
No. It works wherever a line or machine stops for a changeover, including food, pharma and packaging.
They secure the new method: every shift follows the same steps, checks cannot be skipped and you measure every changeover.
