Calculating OEE on a machine that runs different jobs

Ask the expert, Source : The Manufacturer
Published : 06 Nov 2009 16:07

Question: How would you calculate OEE on a machine that runs different jobs?

There are various ways in which OEE is calculated but the version we advocate a lot is shown below:-

So when we consider 1 machine running multiple jobs let us remind ourselves of what OEE is trying to do – it is trying to diagnose to us machine losses due to a number of different factors. So we know that running different jobs may well affect the Availability % given the second loss (Set Ups) could increase if we need to change from part A to part B. Then we need to make sure in our calculation of Productivity that we are using the right ‘theorectical’ cycle time or standard. It may be that different jobs have different cycle times. Therefore it would not be prudent to calculate productivity using the same theorectical cycle time as some jobs may achieve >100% productivity (which means the standard or theorectical cycle time is too low) and conversely some jobs may achieve a very low productivity % using standards or theorectical cycle times which are highly inflated for this job.

In summary, 1 machine running multiple jobs could see a lower Availability % due to changeovers and then we need to ensure that the different jobs use the right standards / theorectical cycle time to calculate Productivity %.

Comments on this story

click here to add a comment