If you were asked what asset absolutely could not stop running in your facility could you identify it? Right now, you are probably thinking through the equipment you have or maybe you already know. You just performed a basic criticality assessment. One of the most fundamental and important tasks you can do for your company is to identify which assets cannot unexpectedly shut down.
Unplanned downtime is the worst-case scenario for any manufacturing company. Lost production effects everyone in the company from scheduling to billing. Mitigating or eliminating unplanned downtime should be the goal of every maintenance technician. Knowing which assets must stay running based on the impact they have on plant production is the first step towards making your life easier. This critically assessment will help you determine which assets in your facility need to be monitored and what frequency of monitoring is appropriate. You will likely decide that some assets should have no monitoring and are best left to run to failure.
The question asked at the beginning either made your minds gears turn or your thoughts went directly to the asset that must run. How did you make that call? What factors did you use to determine that asset was most important? There are many other factors besides production that play a role in determining the criticality of monitoring assets. Here is a quick summary of some factors that need to be considered.
Are there health and/or safety concerns? Some assets can cause significant health, environmental, and safety issues if they fail. If your assets failure will cause any of these to become an issue then it needs to ascend the list of what is most important. While production loss can be very financially painful to the company an environmental or safety hazard can be much worse. No one wants to have an injured coworker or environmental damage occur during an unexpected asset failure.
Will it cause lost production? One of the most stressful times for the maintenance staff is when a production line goes down. Because these outages can quickly cost thousands of dollars, every minute of lost production is cause for concern and in the maintenance world with the production/plant manager breathing down your neck those minutes seem like hours. In determining criticality of each asset, you need to consider how many people will be idled and how large an impact will it have on production if this asset is unavailable. This should be a heavily weighed factor when deciding where an asset falls on your criticality ranking.
Is a batch of product likely to be ruined? In some plants, an extended outage can ruin thousands of dollars of product. For assets that have this vulnerability the cost of a ruined batch needs to be considered and appropriate redundant systems considered. Where this is too costly or not feasible, spare parts should be stocked and a high criticality ranking for monitoring should be considered.
How vulnerable is the asset? An asset under optimal running conditions will run for quite a long time. Reality tells a different story. Often the conditions the asset operates at are less than optimal which shortens the mean time to failure. Understanding and identifying these assets is important to knowing how critical monitoring will be.
Are spares readily available? It always seems like the most important assets are the hardest to quickly repair. No one wants to go to management and tell them that a critical asset has failed and a needed part replacement is days, weeks, or even months out. This can lead to expensive expediting costs and overtime patch work repairs to get back running. Maintaining adequate spares is important but this is not always feasible especially if the spare is very expensive. If the spare is inexpensive it should be kept on the shelf if possible. If spares are readily available and easy to change out then this asset will have a lower rating but if the spare is cost prohibitive, then the monitoring criticality rating will need to be higher.
These factors all play into the criticality assessment of your plants assets. The more historical operating information you can gather as well as equipment manufacturers recommendations the easier completing this assessment will be. This is the first step in helping decide upon a course of action for condition based monitoring, preventative maintenance and predictive analysis. It’s also the starting point for raising the bar on the reliability of your equipment keeping your plant profitably running letting you sleep better at night.