VSM Studio
VSM guide / Lean tools / SMED changeover reduction
SMED changeover reduction
Single-Minute Exchange of Die, step by step: time each element of a changeover with the stopwatch, separate internal from external work, plan the improvements and see the new changeover time. Free, no sign-up.
The SMED method in four steps
1. Observe and time
Film or watch one full changeover, last good part to first good part. Use the stopwatch's Lap button to log every element.
2. Separate
Mark which elements are done while the machine is stopped. Many of them (getting tools, preheating, paperwork) could be done while it still runs.
3. Convert
Move those elements outside the stop: prepare the next job's tools, material and settings before the machine stops.
4. Streamline
Shorten what must stay internal: quick clamps instead of bolts, standard heights, presets instead of trial adjustment, two people in parallel.
Why changeover time matters on a value stream map
Long changeovers force big batches, and big batches create the inventory triangles that make lead time days instead of hours. Cut the changeover and you can run smaller batches and a shorter EPEI (every part, every interval) with the same capacity.
In the VSM Studio builder, open SMED on a process box: it starts from that step's changeover time, and Apply to map sets the new changeover so EPEI, batch sizes and the simulation update.
Questions
What does SMED stand for?
Single-Minute Exchange of Die: Shigeo Shingo's method to bring changeovers under ten minutes (a single-digit number of minutes) by separating, converting and streamlining setup work.
What is the difference between internal and external setup?
Internal work can only be done while the machine is stopped, like removing the old die. External work can be done while it runs, like fetching the next die or preheating it. SMED moves as much as possible to external.
How much can SMED reduce changeover time?
First rounds commonly cut changeover by 30–50% just by separating external work, with no investment. Streamlining with quick-release fixtures and presets often reaches 75–90%.
How do I measure a changeover?
From the last good part of the old job to the first good part of the new one at full speed, including adjustments and first-piece checks. The stopwatch in this worksheet logs each element with Lap.