Down Time Clock
I do not know how many times we had discussions about Equipment Down time and OEE. There are so many definitions about equipment Down Time. If machine is not scheduled to run is this considered Down Time? When the Operator goes on a coffee break – is this considered Down Time? Do we include this in our calculations of OEE? When we conduct a changeover on a press how much time is actually spend on set-up (exchange of dies) and how much time we spent on adjustments – starting, stopping, adjusting, starting, stopping, etc … How much time is spend waiting for the inspection of the first piece?. We huff and puff and argue – since we all want our numbers to look good.
So, here is a simple idea for you. A Down Time Clock. In its purest form it is an analog clock as shown on a picture. The trick is how it is connected to the machine. We use here a “reverse logic”. What that means is that when the machine is running (operating, producing parts) the clock is NOT running. The clock stops. When the machine stops – the clock starts to run.
Down time clock - please click on the file name to view the presentation.
This is how it works – at the beginning of each shift a clock is reset to 12:00. By the end of the shift I know exactly how many minutes the machine was down – not producing parts. The Supervisor records the actual Down Time per shift and the clock is reset to 12:00 again. Simple.
You can see in my picture that the machine was down for 2 hours and 50 minutes. That’s 170 minutes of Down Time per shift. When I started working on this project we were told the “we do not have enough capacity”. After we installed the Down Time Clock and reduced Down Time to less than 30 minute per shift – plenty of capacity was found. We saved about $2000,000 – we did not need to by an extra machine. AND that’s what Lean Transformation is all about.