How to Simplify Maintenance for Critical Production Equipment

In most plants, the most critical production equipment is also the most complex. That complexity means it is the hardest to maintain and the most likely to break down. The designation of production equipment as “critical” is nearly always based on revenue, which means those breakdowns are the most costly. Follow these tips for preventing critical equipment breakdowns and reducing the duration of those that occur.

1. Fix motor lubrication. Motor bearings are lubricated by injecting grease into the zirc provided for that purpose. But not all grease is the same — some greases are incompatible with others, and mixing them isn’t much different from pushing sand into the bearing. Color code all of your grease tubes, and put corresponding color-coded tags on each motor. This will help motor uptime plant-wide. For critical equipment, also install a placard or tag that specifically names the grease to be used.
2. Fix the top five failure modes (by likelihood). First, identify these modes. If you’ve had the equipment for a few years, this information is in your CMMS; simply generate a report, and sort by frequency. For each one, devise a solution. For example, a particular photoeye shakes loose from its mount, causing the PLC to miscount. Change the locking hardware (new bolt, nut, lock washer), and then add a thread-locking compound on the threads. It won’t come loose. Or perhaps a particular 2A fuse blows every few weeks. You track down the cause to a design flaw where one coil too many is powered through that fuse. You could move a couple of coils to a new, additional circuit, or you could rewire using heavier conductors and the next size up fuse.
3. Fix the top three failure modes (by cost per event). You might not have this information readily available for a report from your CMMS, but it’s not going to be rocket science either. If excess glue builds up on the palletizer common to Lines 3, 4, and 5 and causes the motor overloads to open, that’s going to be costly because all three lines will have to stop. Several fixes are possible, and employing as many as practical is the best approach. For example, install some kind of glue guards, automatically monitor (and alarm) the motor current, have a box of overloads ready at the palletizer (and have it checked at the start of each shift), install vibration sensors at any location where dried glue has caused binding, and use photo eyes (with alarm) to ensure the crates/cartons/boxes orient properly into the palletizer so the glue goes where it is supposed to go. And, of course, calibrate and maintain the gluing system.
4. Use video. These days, many people tackle projects that are above their skill level after watching videos on how to do that kind of project. Videos don’t erase a big skills gap, but they definitely can bridge a small one. Maintaining or repairing complex equipment is often challenging because of “How do I?” questions. A maintenance tech who is generally capable can figure out a simple system without much effort. But “on the fly” for a complex system can lead to serious mistakes. A two-minute video showing the exact test sequence or the correct way to make an adjustment can save an hour of trial and error.
5. Use kitting. It might not seem to make good financial sense to buy special tools, jigs, PPE, and test equipment and then store them in a locker near a piece of critical equipment just in case it breaks down. But in nearly all cases, it does. Tally up the cost of these items, and then calculate the cost per hour of downtime. Make a kit with these items, and then label the box of the kit so at a glance people can see what’s in it. Ensure that checking the kit contents is part of the scheduled PM.
6. Manage space. OSHA publishes minimum working space requirements, and those are also in the NEC. Yet in many facilities, these are treated as maximums. For critical equipment, you need to determine how much space it takes to efficiently maintain and repair that equipment. The OSHA table may say 3 ft, but that is for personnel safety — not for revenue protection. If certain functions will require using lifting equipment, then mark off space on the floor to accommodate that equipment. Go all the way back to the main aisle. If maintenance will require using sets of test equipment, allow space for maneuvering a maintenance cart. A good way to ensure you have adequate space is to do a dry run of each anticipated “lots of space” task and see how much you need. Make a video because you will have to fight for that space at some point.
7. Outsource if practical. Often what’s complicated about a particular piece of critical equipment is one module, type of technology, or major component. It may be impractical to send your own people to school on that and somehow give them enough practical experience, but an industrial services firm that services your area may have several people with the required training and experience. Giving them a maintenance contract that includes being on call for breakdowns could be just the solution. This kind of arrangement is often the best solution for electrical infrastructure as well.