Lean methodology
SMED
A method to reduce changeover times and recover available production time.
SMED (Single-Minute Exchange of Die) is a Lean method to systematically reduce changeover times for machines and processes. The method was developed from the 1950s onward by the Japanese industrial engineer Shigeo Shingo and found a major application within the Toyota Production System. The name refers to the goal of reducing changeovers to single-digit minutes (less than ten minutes), although this is not achievable for every process.
In manufacturing, SMED is applied to, for example, product changeovers, tool changes, and machine setups. First, a distinction is made between internal operations, which require the machine to be stopped, and external operations, which can be performed while it is running. By carrying out preparations beforehand and simplifying and standardizing the remaining tasks, the required downtime decreases. These principles are also useful in logistics processes, such as changing packaging formats or converting packaging lines.
Properly applied, SMED leads to less downtime, greater available capacity, and more flexible planning. Shorter changeover times make smaller batch sizes economically more viable, allowing inventories to decrease and organizations to respond more quickly to customer demand. The result is a more agile operation, with fewer startup losses and better utilization of people and resources.
What is SMED?
SMED separates tasks that can only be carried out while the machine is stopped from preparations that can be done in advance.
When do you use it?
SMED is suitable for machines or lines where long changeovers increase batch sizes, limit flexibility, or reduce capacity.
What are the benefits?
Shorter downtime, smaller production batches, and more flexibility to respond to changing demand.