From a Different Angle: A Perspective - Predictive Maintenance or Detective Maintenance?

Are you a big believer in oil analysis, vibration analysis, infrared and the use of various kinds of ultrasound? Are you in favor of the tons of new technologies that let you look into aspects of a machine and see its condition in new ways?

So, what is the problem? The problem is with imprecise language.

How about predictive maintenance (PdM)? If you think it’s hogwash, snake oil, you’re not alone. Only in the last year or two, using big data analysis and Watson-like tools, is any of PdM providing predictions worth the paper they are printed on. So, what is the problem? The problem is with imprecise language. The problem is when words are recruited to mean something different than what they actually mean. When you say something where the meaning is not what the words mean at closer look, you will (intentionally) confuse people.

Is infrared scanning really as its dictionary meaning of “relating to or having the effect of predicting an event or result?” Think about it from your experience – you can predict a failure from a scan, but the scan itself is in no way a predictive.

Figure 1

Perhaps the name of predictive maintenance should be changed to detective maintenance. What is it that you are actually doing? Let’s take a look at an infrared picture (see Figure 1). Sure, you could argue that the middle wire will fail. It might be true, but it is not accurate.

What if it is said that infrared is a way to detect issues that could lead to problems? So, Figure 1 is actually a condition that might lead to problems. Therefore, you have successfully detected potential problems with no bogus prediction involved.

How many times have you faced down meetings where your toes were held to the fire, so to speak, because a prediction from your predictive maintenance didn’t turn out? Executives love it when the maintenance folks scream the sky is falling because their predictive gear says it.

Consider that scenario versus you have detected an anomaly and plan to investigate, fix it, watch it, sit on it, whatever. It sounds more credible, doesn’t it?

Someday soon, there really will be predictive maintenance systems that will text you, “Get out of the area if you want to live” or something equally clear.