Q: I’m running tube mill machine and the machine warm up time is 3 hours, after 3 hours we are able to feed the coil or production start.

Should we consider the 3 hours warm up time as a down time within our OEE? Since in that period we are not able to make any production.

Arno Koch • In order to run production in a correct way, the machine needs to have a certain temperature. So having the machine on the right temperature is a requirement that belongs to your conversion proces, in order to be able to run correctly. Right?

Heating during shifttime

When you heat the machine during shifttime, it reduces its availability to run production. So it reduces the machines conversion capacity. That is what OEE wants to visualize. So we register this time as downtime for OEE.

Heating outside shifttime

You might want to choose to heat the machine outside the regular shifttime: You WILL now register the time as ‘unscheduled’; so it an operational loss to be shown in the OOE since it is also here blocking potential production time (i.e. this time will not be available for new extra shifts).

This might be cheaper since it might require no staff to be present, and when the team comes in, it can start running immediately: OEE goes up, OOE is still affected.

What if you run 24/7

Now what if you would fully schedule the machine (24/7)? In such case the machine will rest on temperature so you do no longer need to spent time on heating: so no reduction on OEE, OOE nor TEEP! This is the difference with ‘Maintenance’, which can NOT be taken out of the machines activities since you need to do it anyway at some point!

Here too: If HEATING reduces your effectiveness: stop it, otherwise: do it and show it!

See also:

Should preventive maintenance go in or out the OEE?

Should breaks go in or out the OEE?

Why ‘Cleaning’ and ‘Maintenance’ should go into the OEE

OEE – OOE – TEEP explained