02-09-2017, 11:49 AM
SMED is one of many lean production methods to reduce waste in a manufacturing process. It provides a fast and efficient way to convert a manufacturing process from running the current product to running the next product. This rapid change is key to reducing the size of production lots and improving flow (Mura), reducing production loss and production variability.
The phrase "minute only" does not mean that all changes and starts should take only one minute, but they should take less than 10 minutes (in other words, "minute of a single digit"). Closely associated is an even more difficult concept, One-Touch Dying Exchange, (OTED), which says that changes can and should take less than 100 seconds. A die is a tool used in manufacturing. However, the utility of SMED is not limited to manufacturing (see value stream correlation).
Frederick Taylor analyzed the non-valuable parts of the configurations in his 1911 book, Shop Management (page 171). However, he did not create any structured method or approach around him.
Frank Gilbreth studied and improved work processes in many different industries, from masonry to surgery. As part of his work, he also studied the changes. His book Motion Study (also from 1911) described approaches to reduce preparation time.
Even the factories of Henry Ford were using some techniques of reduction of the configuration. In the 1915 publication Ford Methods and Ford Stores, the layout reduction approaches were clearly described. However, these approaches never became mainstream. For most pieces during the twentieth century, the economic order quantity was the gold standard for lot size.
The Toyota JIT workflow had this tool change problem took between two and eight hours, Toyota could not afford the lost production time nor the huge batch sizes suggested by the economic order amount. Batch reduction and reduced installation time had been underway in TPS since 1945, when Taiichi Ohno became manager of Toyota's machine shops. On a trip to the USA in 1955, Taiichi Ohno observed Danly stamping presses with rapid die change capability. Subsequently, Toyota bought several Danly presses for the Motomachi plant. And Toyota began working on improving the changeover time of its presses. This was known as Quick Die Change, or QDC for short. They developed a structured approach based on an industry-wide (TWI) training program called ECRS - Eliminate, Combine, Reorganize, and Simplify.
Over time they reduced these times of change from hours to fifteen minutes in the sixties, three minutes in the seventies and then 180 seconds in the nineties.
In the late 1970s, when the Toyota method was already well refined, Shigeo Shingo participated in a QDC workshop. After he began to disclose the details of the Toyota production system without authorization, the business connection was abruptly terminated by Toyota. Shingo moved to the United States and began consulting on lean manufacturing. In addition to claiming to have invented this method of rapid change (among many other things), it changed the name of Single Minute Exchange of Die or, in short, SMED. The single minute represents a minute of a single digit (ie less than ten minutes). He promoted TPS and SMED in the United States.
The phrase "minute only" does not mean that all changes and starts should take only one minute, but they should take less than 10 minutes (in other words, "minute of a single digit"). Closely associated is an even more difficult concept, One-Touch Dying Exchange, (OTED), which says that changes can and should take less than 100 seconds. A die is a tool used in manufacturing. However, the utility of SMED is not limited to manufacturing (see value stream correlation).
Frederick Taylor analyzed the non-valuable parts of the configurations in his 1911 book, Shop Management (page 171). However, he did not create any structured method or approach around him.
Frank Gilbreth studied and improved work processes in many different industries, from masonry to surgery. As part of his work, he also studied the changes. His book Motion Study (also from 1911) described approaches to reduce preparation time.
Even the factories of Henry Ford were using some techniques of reduction of the configuration. In the 1915 publication Ford Methods and Ford Stores, the layout reduction approaches were clearly described. However, these approaches never became mainstream. For most pieces during the twentieth century, the economic order quantity was the gold standard for lot size.
The Toyota JIT workflow had this tool change problem took between two and eight hours, Toyota could not afford the lost production time nor the huge batch sizes suggested by the economic order amount. Batch reduction and reduced installation time had been underway in TPS since 1945, when Taiichi Ohno became manager of Toyota's machine shops. On a trip to the USA in 1955, Taiichi Ohno observed Danly stamping presses with rapid die change capability. Subsequently, Toyota bought several Danly presses for the Motomachi plant. And Toyota began working on improving the changeover time of its presses. This was known as Quick Die Change, or QDC for short. They developed a structured approach based on an industry-wide (TWI) training program called ECRS - Eliminate, Combine, Reorganize, and Simplify.
Over time they reduced these times of change from hours to fifteen minutes in the sixties, three minutes in the seventies and then 180 seconds in the nineties.
In the late 1970s, when the Toyota method was already well refined, Shigeo Shingo participated in a QDC workshop. After he began to disclose the details of the Toyota production system without authorization, the business connection was abruptly terminated by Toyota. Shingo moved to the United States and began consulting on lean manufacturing. In addition to claiming to have invented this method of rapid change (among many other things), it changed the name of Single Minute Exchange of Die or, in short, SMED. The single minute represents a minute of a single digit (ie less than ten minutes). He promoted TPS and SMED in the United States.