Q: What is a ‘World Class OEE’?
Dennis McCarthy • When I say that Effectiveness is a measure of how well you did what you planned to do I want to be sure that the measure excludes time when you didn’t expect to run the machine. For sure the goal is to maximise effectiveness.
The “85% OEE is world class” comes from a TPM book writen by Mr Nakajima who set out what he rightly considered to be world class in a machine shop in 1970’s. This was based on zero breakdowns, 10% of time on set ups, 5% performance loss due speed losses and 1% quality defects. That is still pretty impressive for a machine shop but even a poor process plant would run much higher OEE.
A more robust measure of world class is the OEE improvement trend. From a standing start a 50% increase in OEE over 3 years is a common achievement which often exceeds what they thought of as 100%,
The key for me is to keep it simple, aim for 80% of the answers with 20% of the data and use the measure to drive the improvement trend. As you approach 100% you will also improve process capability and can increase the precision of your measure to raise the bar further. OBE (Overall Batch Effectiveness) has a higher data capture overhead so only use it if you need to.