SMED (Single Minute Exchange of Die)
SMED is a method for drastically reducing setup times. Goal: Every changeover in under 10 minutes -- in the single-digit minute range.
SMED (Single Minute Exchange of Die) was developed by Shigeo Shingo at Toyota. The method distinguishes between internal setup (machine stopped) and external setup (machine running).
The core of SMED: Shift as many setup steps as possible from internal to external. This means: Prepare everything while the machine is still running. Then only perform the unavoidable steps with the machine stopped.
In practice, setup times are often dramatically underestimated because they are accepted as 'necessary.' SMED shows that 50-90% reduction is almost always possible -- often through simple organizational measures without any investment.
Shorter setup times enable smaller batch sizes, which in turn reduce lead time, lower inventory levels, and increase flexibility. SMED is therefore a key enabler for one-piece flow and just-in-time production.
Practical Example
A stamping press has a setup time of 90 minutes. After SMED analysis: 35 minutes are external setup (preparing tools, pre-sorting bolts, reading the next order). These are completed before the stop. Another 25 minutes are eliminated by using quick-release clamps instead of screws. New setup time: 30 minutes -- a 67% reduction.
How Leanshift Helps
The stopwatch function in Leanshift captures every individual setup step with timestamps. Through Muda analysis, you can immediately separate internal and external setup and document SMED progress.
Frequently Asked Questions
What does SMED actually mean?
Single Minute Exchange of Die -- die change in the single-digit minute range. The goal is not necessarily under one minute, but under 10 minutes (single digits).
What is internal and external setup?
Internal setup: Activities that can only be done with the machine stopped (e.g., changing the tool). External setup: Activities that can be prepared while the machine is running (e.g., staging materials).
How long does a SMED implementation take?
An initial SMED workshop typically takes 2-3 days. The first improvements (30-50% setup time reduction) are often immediately achievable. Further optimization follows iteratively.
Related Terms
OEE (Overall Equipment Effectiveness)
OEE is the key metric for machine and equipment productivity. It combines availability, performance, and quality into a single percentage value.
Cycle Time
Cycle time measures how long a single process step actually takes -- from start to finished result. It is the foundation of every process analysis.
Kaizen
Kaizen means 'change for the better' and describes the philosophy of continuous, incremental improvement by all employees -- every day, everywhere.