We all know that preventive maintenance is critical to supporting your assets — but can you do too much of it? Learn how to find the right balance!
Written by Paul Lachance
Ok, before I begin, I need to state: I am a big fan of preventive maintenance (PM) and am not advocating that maintenance operations teams stop doing them. However, applying computerized maintenance management systems (CMMS) intelligence allows maintenance teams to reduce PMs while still achieving maximum uptime.
Traditionally, most organizations issue PMs on a calendar basis. As an example, a manufacturer needs to periodically check on one of the plant’s air handling units (AHU). In a perfect world, a CMMS system triggers a reminder that a PM is due on the unit and the work order is completed in a reasonable timeframe, such as once every four weeks. Even when running a paper-based system, most organizations schedule calendar-based PMs.
But what if that interval is too frequent? In some cases, for example, PM will be completely skipped if there are not enough resources to get it done. In other cases, you struggle to get them done every time, only to find out that you might be doing them too often. There are other variables to drive more efficient, less frequent PM schedules by using meter reading.
The Case for Meter Reading-Based PMs
In many cases there is data to support more intelligent PM scheduling. For example, say that your AHU manufacturer’s suggested maintenance protocol is every 500 operating hours, rather than every four weeks. Unless that AHU is running 24/7, 500 hours of usage will stretch well beyond four weeks.
Most CMMS systems allow users to enter meter readings (MRs), numerical readings that can be associated with any asset. A CMMS system can set MRs different variables, i.e., hours run, pressure, temperature, widgets produced, etc., and show maintenance staff when an MR for a piece of equipment is outside of acceptable tolerance. MRs can also be used for trending purposes.
Another excellent use of MRs is to help determine when PMs should be performed. For example, if you want to track “hours run” for an AHU, take periodic meter readings. Once you hit a threshold of 500 hours, you can then initiate a PM.
Too Much of a Good Thing
But to prove your current PM schedule is too frequent, you should start taking metering readings and tracking them in your CMMS system. It may turn out that your AHU unit is running 15 hours per day, averaging 105 hours of runtime per week versus the total 168 hours that make up a week. Initiating a calendar-based PM schedule every four weeks, based on the 105 hours of weekly run time, would trigger the PM every 420 hours – 80 hours shy of the manufacturer’s recommended schedule or nearly or an extra week of unnecessary maintenance checking. Over time, these extra PMs would add up to wasted parts and labor costs.
A manufacturing operation may need to schedule PMs based on accumulating production volume, i.e., output in widgets produced, with maintenance warnings issued at set intervals. A calendar-based schedule will not change as production volume changes over time, again risking too frequent or infrequent PMs.
Do Your Research
To develop a more accurate PM schedule based on meter readings, know your equipment and gather accurate data to support the manufacturer’s recommended maintenance schedule. Rely on your equipment vendor or previous experience to determine the most accurate intervals to perform PMs. Make sure your CMMS system supports both calendar and meter-reading based PMs.
Can you schedule too many PMs? Yes, you can. Still, too many PMs are probably better than not enough. CMMS and meter readings can help any organization implement a more intelligent, accurate and efficient PM schedule that strikes the right balance.
To learn more about PM scheduling, read our free e-book, "Kickstarting Your Modern Maintenance Program for Manufacturing"!
ABOUT PAUL LACHANCE
Paul Lachance has spent his entire career devoted to optimizing maintenance teams by enabling data-driven decisions and actionable insights. He wrote his first CMMS system in 2004 and has since spent his professional career designing and directing CMMS and EAM systems. A regular speaker at national tradeshows, he’s been featured at IMTS, Fabtech and SMRP as well as several industry magazines. He currently serves as the Senior Manufacturing Advisor for Dude Solutions.