What SMED is
SMED (Single-Minute Exchange of Die) is a methodology created by Shigeo Shingo to cut changeover or setup time to under 10 minutes (single digit). Long setups are one of the main reasons companies end up producing in large batches, which runs counter to Just-in-Time.
Internal vs. external setup
Internal setup
Activities that can only be done while the machine is stopped, like physically swapping a die or tool.
External setup
Activities that can be prepared while the machine is still running, like staging tools or pre-heating dies.
The right question isn't "how do we change over faster," it's "what part of this changeover actually needs the machine stopped?"
Step-by-step application
- Film the current changeover start to finish and time every activity
- Separate internal from external activities
- Convert as much internal work to external as possible
- Simplify remaining internal activities (standardize heights, use quick fasteners)
- Eliminate trial-and-error adjustments with markings and jigs
Cutting setup time is what makes the production leveling described in the Heijunka article actually achievable.
Want to apply SMED alongside leveling?
Read about Heijunka and how to distribute production evenly.
Read the article
About the author
Lean Manufacturing & Behavioral Management Specialist
Over 20 years in the automotive and metalworking industries (GM and Dana), Lean Manufacturing practitioner since 2006. SENAI instructor and mentor in Brazil’s Brasil Mais Produtivo program, delivering consulting, training and audits for 50+ companies, combining quality, productivity and people development.