In our last iLearnReliability Tip #3: Critical Asset Assessment, we discussed completing an FMEA and some data analysis on our most critical assets. It is now time to take a hard look at our asset's Preventive Maintenance (PM) library. Often times reliability engineers and managers struggle to find the manpower resources to deploy condition monitoring.
Here is a great way to find "hidden resources". Scrub your PM library based on criticality. A key RCM principle to consider is that for a PM task to be considered viable it must: 1. Be non-invasive or intrusive to the equipment 2. It must be quantifiable in nature 3. It cannot be replaced by a condition monitoring task
PMs often require machines to be taken out of service, are intrusive to the machine where we may accidently introduce a fault, and often times are not quantifiable in nature. Experience demonstrates that in many cases, only 30%-40% of a manufacturing facility's PM library is valid as written, based on the rules above.
So take a hard look at your PMs. You may find that 30% of your PMs are unnecessary (based upon the rules above) and can be replaced by predictive maintenance techniques, 30% of your PMs will provide more value if updated, and 30%-40% of your PMs are likely to be valid in their current form.
Imagine what you can do with the human resources that you've made available through the elimination of unnecessary PM tasks? You can 1) deploy additional condition monitoring technologies to gain better insight of your asset condition, 2) avoid introducing faults by eliminating intrusive inspections, and 3) gain better overall insight of asset condition to support improved reliability... all with your existing workforce.