Overall equipment effectiveness - Computing OEE taking all machines taken together

[Andrews]

We are computing OEE taking all machines that we have inhouse together. Setting time, breakdown hrs., etc are taken for all machines together and a single OEE is computed. Is this right? or should we compute for only the contsraint machine.

[Marc]

I would be looking at each machine. You may have a process where you have recognized a 'constraint' machine and bought a second one or something like that. I don't know how you could do a single OEE without having data on each machine/operation/etc.

[peteroldfield1971]

You could measure this in 2 ways. First, calculate OEE for individual machines. Then use these figures to calculate plant efficiency. This would highlight individual machine concerns. You could have a plant efficiency at 75% but this would not show that 2 machines could be running at different levels of efficiency. So in effect one machine could be carrying the other. I guess its all down to the amount of time and effort you can put into it each week/month and what data is available.

I have attached an example of the difference in machine efficiency and plant efficiency for you to review.

[Randy Stewart]

If you are using OEE to establish throughput, you are making it more difficult to identify bottle necks by lumping all equipment together.

What I have found to be very beneficial in the past has been to do a Value Stream Map before applying the OEE calculations. It identifies restraints and then you can put actual numbers on how the restraints are detrimental to the process.

[Andrews]

Thanks everyone for the response.

Randy,
What does value stream map mean? Kindly explain.

[Howard Atkins]

For some reason there was no reply-
Try the folowing threads

Have any of you heard of a Value Stream Mapping

VSM (Value Stream Mapping) - Use constraints or leave 'wide open'?

[Marc]

Howard - Thanks for noticing and helping out!

Also see: OEE - Overall Equipment Effectiveness - Initials and Definition

[wmarhel]

Here's another worksheet. Just enter the data in the yellow fields.

Wayne