How do you maintain compressed air equipment during a slowdown or complete shutdown? With COVID-19 impacting commerce and production across the globe, this is a question many manufacturers are facing right now.
While some essential businesses are ramping up operations or rapidly retooling to make much-needed medical supplies, others find themselves bringing manufacturing lines to a halt. The coronavirus has forced many businesses deemed “non-essential” to slow operations to minimize the number of people on site or to shut down entirely. If you are in this category, maintaining compressed air systems may be the farthest thing from your mind…but it shouldn’t be. Operating at reduced capacity for extended periods can lead to damage to your air compressor and other system components if they are not maintained properly. Taking a few key actions now and over the course of the slowdown will prevent unnecessary repair costs and ensure that your compressed air system will be ready to roar back to life when you are.
How Operating at Reduced Capacity Affects Your Air Compressor
Rotary screw air compressors—by far the most common type of air compressor deployed in manufacturing—are especially susceptible to damage during a slowdown or shutdown. These compressors are designed to operate at or near maximum capacity. When demand for air drops too low, a couple of things can happen:
- The system will not run hot enough to burn off excess water in compressor coils and lubricating oils. When water does not burn out of the oil, the oil will break down more quickly and will not provide sufficient lubrication for the pump.
- The system will begin short cycling (turning on and off too frequently). When demand is low, the system will shut off the motor to go into standby mode. When pressure in the system drops below a certain level, the system will turn back on again until it is brought back up to pressure. Frequent loading/unloading cycles cause excess wear on the compressor motor and controls, leading to early failure.
How to Protect Your Air Compressor During a Slowdown or Shutdown
There are several steps you can take to protect your compressed air system during a slowdown or shutdown. These include both one-time actions, such as shutting down a compressor or adjusting compressor controls, and ongoing inspection and maintenance activities. Your plan of action will depend on whether you are shut down entirely or operating at lower capacity and how long you anticipate your slowdown will last.
Shut Down Unused Air Compressors
If your manufacturing facility has completely shut down production, you should shut down air compressors as well. This will prevent damage to the system caused by operating in low-demand conditions. If you have multiple compressors and are anticipating an extended slowdown, shut down all compressors except the smallest one that will meet your air demands.
Increase Load on the System Artificially
If you are operating at significantly reduced capacity, one way that you can protect your air compressor is to increase air demand artificially. This can be accomplished by bleeding off air periodically. Venting your compressed air system once per day so that the compressor can operate at temperature for at least 30 minutes will enable the system to burn off excess water in the oil and compressor coils.
Adjust Compressor Controls
Many rotary screw air compressors have an “auto dual” option that will automatically put the compressor in standby mode when more air is not needed. This will reduce excessive idling time and wear and tear on the system. This works best if you have plenty of air storage. Without adequate storage (the recommended amount is 3-5 gallons of storage per CFM of compressed air), the system will cycle on and off too frequently.
To reduce short cycling, you can adjust your compressor controls to broaden the operating pressure band. Typically, pressure bands are kept within a narrow range (5 – 10 PSI) so that the system always has enough pressure to meet demand. When demand is low, that means the system is cycling off every time the pressure drops by this amount and staying on just long enough to bring it back up to pressure. Widening the pressure band to a 25 PSI range, for example, will lengthen your load/unload cycles: the system stays off for a longer period as pressure drops, and then stays on longer to re-pressurize the system. Lengthening cycles reduces wear and tear on the compressor motor and controls.
Check Oil, Drains, Dryers and Filtration Equipment Daily
Regular maintenance of your compressed air system is always important, but during a slowdown, it is doubly so. Air compressors running at lower duty cycles tend to pass more moisture and oil downstream. This will cause problems for your system if not detected and addressed.
Oil should be checked daily for excessive water. Do this in the morning before the machine is started. Simply drain a small amount of oil out of the sump tank. Since oil is heavier than water, any water that has accumulated in the pump oil will have settled to the bottom overnight. If you see water coming out of the sump before you see oil, you know that you have a problem. Draining the excess water from the sump daily prior to starting the machine will help. You should also follow the instructions above for artificially increasing demand to burn off excess water each day.
It is also important to check drains, dryers and filtration equipment daily. Excess oil passed through the system can build up in filters and drains downstream, causing them to fail or reducing system performance. Plan to change filters and clean drains more frequently to compensate.
Downsize Your Compressor
Downsizing your air compressor is a last resort, especially in response to a temporary, crisis-driven slowdown such as the one we are seeing now. If you believe that your business will rebound to full volume after the current crisis has passed (and we believe most will!), it doesn’t make sense to reduce your manufacturing capacity permanently. Downsizing your air compressor is a step that should only be taken if you believe that you will be permanently operating at reduced capacity.
On the other hand, if you were already considering purchasing a backup air compressor, now may be a good time. Installing a smaller backup system enables you to shut down your main air compressor temporarily and switch over to your new backup for the duration of the slowdown. Then, when business is back to normal, you can keep the smaller compressor as an emergency backup or use it to increase manufacturing capacity. If you’re worried about cash flow, you can buy a used air compressor for as little as half the cost of a new system.
Get Ready to Ramp Back Up
While things may look dire right now, the current crisis will pass. When that happens, many manufacturers will find themselves busier than ever as they ramp up to fulfill backed-up orders and pent-up demand.
Now may be a perfect time to consider making needed efficiency improvements or repairs, so your compressed air system is ready to operate at peak performance. With manufacturing lines already stopped, this work can be completed without interfering with production. If you are experiencing a slowdown or shutdown, it is likely that your people are already out of the building, minimizing virus exposure risks.
If you’ve been putting off regular preventative maintenance, you should do it now. This may be a great time for an in-depth system evaluation, inspection and tune-up. Fluid-Aire Dynamics can evaluate your system, perform standard maintenance, and recommend improvements or preemptive repairs that will improve the efficiency of your system and prevent problems down the line.
Should you repair leaks in your compressed air system during a slowdown? There are different schools of thought on this question. Repairing leaks will make your system more airtight and efficient—generally a good thing! However, this will also further reduce demand on your compressed air system, which could put additional stress on your air compressor if you don’t compensate in other ways.
We recommend taking advantage of the time when your facility is idle to complete leak repair so that you will be running at maximum efficiency when your lines are ready to start rolling again. You may even be able to get this done for free through the Fix-it-Now Leak Repair program. Just be aware of how much further demand has been reduced after the repair. You may need to bleed off more air after leak repair to maintain higher demand or take other compensatory actions.
Other Energy-Efficiency Upgrades
A slowdown may also provide an opportunity to take the time for other system upgrades to improve energy efficiency or increase your capacity. You may want to consider adding a backup system, re-configuring air supply lines, upgrading to variable speed drive, adding air receiver tanks to improve storage capacity or making other improvements.
Your energy company may even help you pay for improvements that increase the overall efficiency of your system. Introducing energy-saving improvements now will pay dividends when you are back to operating at full capacity.
Let Fluid-Aire Dynamics Prepare You for Better Days Ahead
At Fluid-Aire Dynamics, we firmly believe that the best days for American manufacturing are still ahead. We are working with our customers to ensure that we all get through this together.
Fluid-Aire Dynamics is considered to be an essential business, and we are still operating to perform repairs, maintenance and upgrades for our customers. (Of course, we are following all health recommendations during this time to protect your people and ours.) We can work with you to evaluate your system, help you maintain it while demand is low, and make sure you are ready for the next business upswing.