Air compressors use considerable volumes of energy during a typical work cycle. When you add up all the expenses of operating a facility, any savings can help you boost your bottom line. With air compressors, savings come down to efficiency, which depends on a steady maintenance regimen. The following 13 ways to reduce compressed air costs can help you increase your productivity, boost your earnings and prevent costly repairs and system downtime.
Think of it this way. A calendar week consists of 168 hours. Unless you actually use your compressor for processes that run nonstop, 24/7, there is no reason to have your compressor running every hour around the clock. If you only use the compressor for eight, 10 or 12 hours per day, five days per week, you would only need to have the compressor on between 40 and 60 hours in a given week. By cutting the hours of usage down to a typical working week, you could cut your energy consumption down by two-thirds and see significant savings in your subsequent energy bills.
To save money on compressed air costs, it is crucial to eliminate air leaks as much as possible. With air compressors, four-fifths of the energy consumed in a given cycle turns to heat, and only the remaining 19 percent yields air power. When leaks and other performance issues plague the compressor, the overall efficiency drops even lower than that one-fifth level. It is, therefore, essential to inspect your compressed air system for leaks regularly and perform maintenance when necessary.
Most leaks are hard to detect because they are either located in hard-to-access spots or the rupture is not large enough to be audible at arm’s length. Depending on the scope and magnitude of your operations, the costs associated with air leaks could spill into the four- or five-figure range each year. The most effective way to reduce leaks is to use an ultrasonic leak detector, which can detect some of the smallest and faintest leaks. With a leak detector, you can spot and remedy leaks in their formative stages before they expand and lead to costlier problems.
The first place to check is the pipes, which could be vulnerable to cracks if corrosive elements are allowed to deposit along the length of a given pipe or any of the connecting points. If you spot dust particles or sludge around the piping, clean these spots as thoroughly as possible. To keep each surface in optimal condition, you must keep each pipe clean and dry.
During these inspections, check the filters and drains to ensure that no dust or water accumulates within the system. When mist and dirt get trapped within the compressor and deposit on various internal parts, corrosive gunk can take hold and lead to rust, leaks and system strain.
Even when your system is free of leaks and dirt, you can cut compressed air costs even further by reducing the pressure to the levels required for a given operation. At many facilities, pressure levels are set to maximum thresholds to accommodate the highest-pressure applications. The trouble is, these high-pressure tools and applications might only account for a fraction of the air-powered arsenal.
If you only use high-pressure tools on a part-time basis, consider the possibility of separating those tools from the rest of your equipment. This way, you could run your compressor at medium pressure and save energy through most of your working hours and only increase the pressure when necessary.
If you operate a large facility with multiple compressors, designate each machine for different pressure levels. For example, if you have a range of lower- or medium-pressure applications and only one or two that require high pressure, you could save energy by moving those latter applications to a second compressor specifically designated for such tools.
Further problems could arise if the timer drain gets stuck in the open position. Depending on the placement of your air compressor and the maintenance schedule of your staff, an open drain door might go unnoticed for several weeks or months. That whole time, compressed air will inevitably leak from the system.
To get around this problem, use a zero-loss drain. This way, your system will not be vulnerable to air loss each time you drain the system. By investing in a zero-loss drain, you can save in the long run by preventing the air loss and maintenance costs that will mount over time due to the problems associated with timer drains.
Pressure drop is liable to increase when the routing is lengthy and complicated. The longer each flow must travel, the more the pressure drop will be by the time the air reaches its end-point destination. If the pipes are changed in a way that doubles the flow, the pressure drop could increase four-fold. Consequently, your pneumatic processes would be rendered weaker, and the system overall would be less efficient because of tight, lengthy piping.
In recent years, piping has changed on newer compressed air systems. If your current piping was used years earlier on a smaller compressor, consider a new arrangement. If your pipes are smaller than the outlets on your compressor, trade up to a new set of pipes that are wider in diameter. Rather than complicate matters, arrange your pipes so that the flow is wide and as short as possible.
To further cut compressed air operating costs, clean the filters throughout your system on a regular basis. On each unit, the filters play a critical role in the process of the system by capturing dust and dirt from the incoming air. This way, the ambient air is free of air-bound particulates by the time it enters the pressurization chambers. Without the filters, the pressurized air would likely be contaminated and rendered far less effective for pneumatic applications. Moreover, dust and dirt would filter through the air compressor and accumulate on various internal parts.
Depending on the volume and frequency of your operations, each filter should be cleaned on a weekly or monthly basis. Make sure that all dirt is removed before you restart the compressor. Additionally, clean any secondary filters, such as air-line or point-of-use filters situated outside the compressor room or away from the actual units. When a filter appears worn or soiled with residue, change out the filter with a matching replacement.
When it comes to the operation of your system, one thing is certain — maintenance amounts to savings on compressed air operating costs. To maximize the functions of your air compressor, you must inspect the unit on the outside and inside periodically. In addition to the pipes and filters, you should regularly inspect the motor fans, drip tray, belt and lubrication.
The fans in your air compressor perform a crucial function by lowering the heat inside your unit. To keep the fans fully functional, check the blades for dirt or lint. If one of the blades appears dull or cracked, trade out that fan for a newer duplicate.
Each time you open up the air compressor, inspect the belt to make sure that it has the proper flex to function properly. Give the belt a slight pull to test its elasticity and run your finger across the side for signs of cracks or dullness. When you check the lubrication, make sure that it has the proper color and viscosity. If the machine has been excessively hot, the lubrication could melt and leave the internal parts vulnerable to grinding and rust.
In some cases, various minor acts of compressed air usage can amount to wasteful behavior. For example, if pneumatic blowers are used by factory floor personnel to dust off tables and shelves, air power is being consumed for a function that could just as easily be performed with manual brushes.
In other cases, extraneous compressed-air usage can quickly become a costly habit. For example, if air blowers are being used to cool the interior of an industrial facility, you could be faced with soaring energy costs over a function that would be much better achieved with fans or an air conditioning system.
In a compressed air setup, the size and placement of the air receiver is a major determining factor in the overall operating cost of the system. For each successive pressurized air supply, the air receiver functions as a placeholder between the compressor and the system at large. Within the air receiver, the pressure is modulated to suit the demands of the application at hand.
In some factories, technicians place the air receiver before the air dryer. This way, lingering traces of oil and condensate are removed from the process before it reaches the dryer. The downside to this arrangement is that the receiver is forced to hold denser supplies of air. If the demand surpasses the capacity rating, the dryer might get overloaded and increase the dew point pressurization.
The other option is to place the receiver after the dryer. This way, spikes in demand are received with dry air. For protective purposes, the ideal arrangement is to affix the supply side with two receivers. In this arrangement, the first receiver controls condensate dropout while the second handles varying demand levels.
Before these questions can be answered, the applications of your compressed air system must be taken into account. For example, the level of your drying needs could depend on whether you operate in a humid environment. That said, certain principles apply in all cases. For starters, never allow pressurized air to dry beyond the required level of the application, as doing so will make your operations more costly. The more efficient option is to first use a refrigerant dryer and only apply further drying on an as-needed basis, as determined by the application. To avoid additional pressure drop, limit your use of filters to the bare necessity.
One of the easiest ways to save money on compressed air energy is to pay for a professional tune-up of your air compressors and peripheral parts. When you hire a third-party maintenance technician to come to your facility, that person will likely spot issues that your in-house staff may overlook. Professional maintenance techs have inspected hundreds of different air compressors and know about all the common mistakes that users make with these machines.
A professional technician will come to your facility with equipment and tools to evaluate and tighten up your system in all the weak spots. If your connectors are loose, the technician will tighten these spots and run a test on the compressor to verify that the leaks have been sealed. If your compressor is losing oil, the technician will diagnose the problem and rectify the situation, whether this involves a new compartment or a new set of fasteners.
If the time has come to replace your current air compressor, you might discover that a completely different type of compressor will make your operations far more efficient and help you save money.