More preventive maintenance is not necessarily the answer

More is not necessarily better when it comes to preventive maintenance. In order to strike the perfect balance, you have to find the right amount of maintenance as well as what tools best accomplish the job.
By Shon Isenhour, Eruditio October 17, 2017

Image courtesy: Bob VavraLet’s first talk in extremes: there are some facilities that are truly reactive in nature and only fix equipment when it breaks. This keeps them very busy and leaves little time to do preventive (PM) or predictive (PdM) maintenance. This can lead them into a death spiral of unreliability. Many of these sites believe that if they could just get a bunch of PMs, then they will escape the spiral.

On the other side of the spectrum, there are facilities that over time or, in response to an incident, have created a large portion of their backlog that consist of PM work. Again, they face many breakdowns and unreliability. If PMs are good why might these facilities experience an increase in breakdowns and unreliability?

One answer is infant mortality. In other words, by doing more invasive PM inspections, such as opening a gear box to inspect the teeth, they actually induce failures. These failures can come from dirt and debris that accidentally get into the box while it is open, or it may result from improper reassembly upon completion. In this example and many others, the use of PdM tools could eliminate unnecessary PM activity, eliminating the infant mortality issue entirely.

The second enemy in using too much PM is the possible loss of effectiveness due to low quality procedure, or poor execution in the field. This could result from labor overload, or from a lack of training on the added task. Many facilities ramp up the number of PMs by getting suggested PMs from vendors or coping other facilities PM procedures. This leads to tasks that don’t address the failure modes and in many cases, may not even address the equipment in question. 

So if you want to increase your level of preventive maintenance and your reliability take these steps:

  1. Create a plan of what equipment and when. This could be based off of criticality.
  2. Generate solid craftsman-reviewed PM tasks that are failure mode based and detailed to the right level. You can base them off of examples if they are reviewed and verified prior to deployment.
  3. Finally, use the predictive maintenance tools to eliminate the invasive preventive maintenance that plagues you by adding defects to your system.

Grow a good program a little at a time as apposed to a bad program overnight.

Shon Isenhour is a founding partner at Eruditio and is a part of Plant Engineering’s editorial advisory board. Eruditio is a CFE Media Content partner. This article originally appeared on Eruditio’s website.