Updating the oee towards the iei
“This morning when I arrived at the plant, with my warm coffee in hand, I was interrupted by the quality manager with the scorecard of the month’s indicators. Why the hell are we down 0.2% in OEE compared to last month’s average? I don’t know, let me get on with it and I’ll tell you something this afternoon.” ….. Buff, what a day we have ahead of us, it’s time to review all the production data to see which casing has broken on the packaging line, which is always doing its thing…., as if we had nothing else to do!”
Nowadays, a manufacturing process cannot be understood without an Overall Equipment Effectiveness (OEE) control. But if we stop to think about it, things are no longer as they used to be. At least, not like when OEE (Overall Equipment Effectiveness) was defined more than 40 years ago. Neither the machinery had the same PLC’s, nor the current networks and databases, nor the Scada software, nor the MES and much less the ERP. They have little to do with the last decades of the last century. Today everything is for yesterday and the data has to be there immediately.
The context is not the same either. Who would have thought that in the last three years, a global pandemic would be declared, that the logistics chains that have brought us this far would fall like a house of cards, that we would see the automotive industry giant tremble because of component shortages, that purchasing departments would have to negotiate raw material prices every week because they suffer the highest variations known to our generation, that changes in energy prices have pushed inflation to double-digit figures not seen since the end of the cold war and that we would see a war in Europe that rewrites centuries-old military strategies due to changes in technology, and that it is difficult to imagine the consequences we will have in the medium and long term… . . Yes, I think you will agree that the times we live in have changed somewhat.
And yet here we are, with the initial story about the OEE which has interrupted our coffee. Isn’t it about time to update the index a bit?
“It took us a while, but after reviewing the week’s production data, we finally found the reason for the decrease, we found an increase in the temperature of a drive, which, without being critical and without triggering alarms, caused excessive consumption. When we went to check the drive, we saw that it was fine and luckily we asked the operator of the same shift that had problems. The failure was caused by a damaged part of the conveyor chain. It caused only sometimes a small jam that caused part of the line to fail. The operator, following the rules, removed the product that was getting stuck on the belt and passed it to discards.”
What if the OEE, which we already monitor, included more information that would help us detect this type of problem? Wouldn’t it be better to have it within a single indicator?
If we do, we have the iei, the industrial efficiency index, a value that adds two of the important parameters that today should already be included, energy and raw material. In a single indicator, we can group and not only know how much we manufacture, but we can also know how we manufacture it. In the same indicator we have the energy we use, whether it is electricity, gas, steam or compressed air, as well as the ratio between raw materials entering the process and the amount that is lost due to discards, scrap, samples for off-line quality controls or production failures.
The advantage of grouping them into a single indicator, in addition to reducing the KPI’s to control, is to be able to automate the reports in case of deviation, to be able to generate alarms, to have a control of incidents and to have a history that allows us to draw correlations or conclusions to improve the process continuously.
Isn’t it time to adapt to the current era and be able to have that coffee with a little more peace of mind?
Miguel Madrid
(Versión en español aquí)