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Monday, February 4, 2019

PEMAC Conference Discussion About The Lies Reliability People Tell.


We talked about lies nothing but lies… In our PEMAC Conference table sessions we talked about some of the maintenance and reliability models and tools that we use and some of the subtleties that often aren’t understood or taught correctly. 

We discussed the six failure curves of RCM (Reliability Centered Maintenance) and how many think and explain them as relating to types of asset or classes of assets but in reality they relate to types of failure modes of assets. This means that one asset could have many failure modes that relate to different curves so suggesting that one of the curves represents an asset class is incorrect. This explanation helps individuals to then understand that 68% of the failure modes are infant mortality according to the Nolan and Heap study, but 68% of the assets don’t always fail in the infant phase. It is like the difference in an ice cream shop saying 68% of our flavors have chocolate in them but it does not mean that 68% of the ice cream the shop sells has chocolate in it. Some people like vanilla and maybe a lot do. If so, you could sell a majority of vanilla even though most of your other flavors have chocolate in them. With this logic, you could have 68% of your failure modes be infant mortality but when you look at the number of failures they would be a majority of wear out because of the environment or equipment type or process.

The second lie we talked about was RCA (Root Cause Analysis). The table discussed that there is no such thing as root cause because every single problem has root causes. All problems need both actions that happen instantaneously and conditions that have existed over time. The example we used was fire. Fire does not have a cause it has three causes. Ignition which is likely instantaneous and fuel and oxygen which are likely conditions that have existed over time. The key is it takes all three causes not just one root cause.

We finished up by talking with the group about where and how they could use these learnings in their site to improve their reliability programs. 

Do you agree with our thoughts? Share your opinions below. 

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