Single-minute exchange of die

Single-minute digit exchange of die (SMED) is one of the many lean production methods for reducing inefficiencies in a manufacturing process.

They developed a structured approach based on a framework from the US World War II Training within Industry (TWI) program, called ECRS – Eliminate, Combine, Rearrange, and Simplify.

Besides claiming to have invented this quick changeover method (among many other things), he renamed it Single Minute Exchange of Die or, in short, SMED.

[4][5] Toyota found that the most difficult tools to change were the dies on the large transfer-stamping machines that produce car vehicle body parts.

Installing the die against these measurements, rather than by human eyesight, immediately cut the change-over to a mere hour and a half.

Using these processes, Toyota engineers cut the change-over time to less than 10 minutes per die, and thereby reduced the economic lot size below one vehicle.

SMED makes load balancing much more achievable by reducing economic lot size and thus stock levels.

The SMED concept is credited to Shigeo Shingo, one of the main contributors to the consolidation of the Toyota Production System, along with Taiichi Ohno.

Issues of effective communication between the operators must be managed to ensure safety is assured where potentially noisy or visually obstructive conditions occur.