SMED Part 2 – Quick Releases
A commonly used lean tool/concept in manufacturing is Single Minute Exchange of Dies (SMED) or quick changeover. By definition changeovers from one job to the next is waste. It does not add any value to the product/service, nor is the customer willing to pay for it. Since it is waste but necessary in many operations, the goal should be to be as quick and as efficient when changing over as possible.
Shigeo Shingo showed how getting changeovers done in just a few minutes can reduce the batch size that can be produced, which creates less inventory and increases the cash flow. When achieved, a changeover that is done in less than 10 minutes will save a lot of money. The ideal state is to get the changeover to instantaneous so no capacity is lost.
During my time I have seen what I call three levels of the SMED concept that can help depending on where you are with implementing quick changeovers or lean. This is the second of three parts explaining the different levels I have seen. I hope this will help others with their SMED efforts.
Another big concept in SMED that I have seen help many times, is the quick release and tool modification concept. Too many times, I have seen examples of turning screws or bolts that are 2 inches long in order to secure something. Quick release clamps give the functionality of holding something in place without the need to screw something in.
(click on image for larger view)
The example above shows a screw with a knob that was used on 4 corners of a screen to hold it in place. A team changed this to 4 lock down clamps that take less time to secure than one of the screw knobs.
Another concept is trying to find ways to modify tools that are used in order to prevent wasted movement during the changeover. I worked with a team one time that needed 2 different size wrenches to do the changeover inside a piece of equipment. Everything they needed the other size they would have to get out of the equipment, get the wrench and then get back in to work. The team decided to cut the two wrenches in half and weld the sizes they needed together in order to make things quicker. Here is another example:
On the left the operator has to scoop the powder and then strain it into a container and then pour it into the machine. The modification on the left had the strainer built right into the pour slot for the powder on the machine.
Getting quick releases and modifying tools may be something that can help your SMED efforts.