6 steps to optimizing your compressed air system

If you’re a follower of the EXAIR Blog, you’re probably well aware that compressed air is the most expensive utility in an industrial environment. The average cost to generate 1000 Standard Cubic Feet of compressed air is $0.25. If you’re familiar with how much air you use on a daily basis, you’ll understand just how quickly that adds up. To make matters worse, many compressed air systems waste significant amounts of compressed air just through leaks. According to the Compressed Air Challenge, a typical plant that has not been well maintained will likely have a leak rate of approximately 30%!! Good luck explaining to your finance department that you’re carelessly wasting 30% of the most expensive utility. To make sure you get the most out of your compressed air system, it’s important to follow the Six Steps to Optimizing Your Compressed Air System.

Starting with Step 1: Measure the air consumption to find sources that use a lot of compressed air. In order to have an understanding of your compressed air usage across various processes and in your entire facility, you have to measure and produce a baseline. Without a measurement of usage, there’s no way to determine your actual costs or evaluate opportunities for savings. To do so, EXAIR offers a range of Digital Flowmeters from stock. The Digital Flowmeter provides a digital readout of the exact amount of compressed air being used. Many companies will install the DFM on each major leg of their air distribution system to allow for constant monitoring and provide a benchmark of compressed air usage.

Once you’ve measured your baseline, it’s time to explore another simple avenue of savings. Step 2 in the process is finding and fixing leaks in your current system. EXAIR offers our Model 9061 Ultrasonic Leak Detector to allow you to locate and fix any leaks within your distribution system. With an unmaintained system wasting on average 30% of the produced volume, this one seems like a no-brainer but is often overlooked. If you can hear the leak without the help of a device like the ULD, it’s a VERY bad leak. These should be located, tagged, and repaired ASAP!

After getting a baseline measurement of the air consumption in your facility of compressed air usage and locating and fixing leaks in your system, it’s time to begin implementing some changes. Step 3 of the 6 Steps to Optimizing Your Compressed Air System covers upgrading your blowoff, cooling, and drying operations using engineered compressed air products. EXAIR manufactures a variety of products that can help to ensure you’re using your compressed air in the best way possible. While it may seem simple, easy, and cheap to use something like an open-ended pipe or tube for blowoff, the fact of the matter is that the volume of air that these homemade solutions use quickly make them more expensive. Look no further than EXAIR when seeking a safe, efficient, and reliable engineered blowoff solution.

EXAIR Intelligent Compressed Air Products such as (left to right) the Air Wipe, Super Air Knife, Super Air Nozzle, and Air Amplifier are engineered to entrain enormous amounts of air from the surrounding environment.

Step 4 may be the easiest of any of the others. TURN IT OFF! You can’t waste compressed air when it’s turned off. By strategically placing valves at various points throughout the distribution system, it allows you to isolate areas of the facility that may not require continuous compressed air usage. It isn’t exactly feasible to eliminate every single leak, so even if you’ve closely followed Step 3 it’s still beneficial to close some valves here and there to further reduce your consumption. In some applications, such as products traveling on a conveyor, it may be possible to utilize a product like EXAIR’s Electronic Flow Controller to ensure air isn’t wasted in between parts on the conveyor.

The 5^th step in the 6 steps to optimizing your compressed air system highlights the use of intermediate storage of compressed air near the point of use. Receiver tanks are installed in the distribution system to provide a source of compressed air close to the point of use, rather than relying on the output of the compressor. Compressed air receiver tanks are an integral part to many compressed air distribution systems. Compressed air is stored at a high pressure after drying and filtration, but just upstream of point of use devices. The receiver tank is charged to a pressure higher than what is needed by the system, creating a favorable pressure differential to release compressed air when needed.

Think of a compressed air receiver tank as a “battery”. It stores the compressed air energy within a system to be used in periods of peak demand, helping to maintain a stable compressed air pressure. This improves the overall performance of the compressed air system and helps to prevent pressure drop. They should be placed strategically to provide a source of compressed air to intermittent high-volume applications.

The last step, Step 6, discusses the use of pressure regulators at the point of use. Pressure regulators are available to control the air pressure within the system and throttle the appropriate supply of air to any pneumatic device. As the last of the six steps to optimizing your compressed air system, controlling air pressure so that you’re only consuming as much as necessary can have a dramatic impact. EXAIR sells a variety of systems that will include a suitably sized pressure regulator to ensure you’re operating as efficiently as possible.

Follow these 6 steps and make sure you get the most out of your compressed air system!

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@EXAIR.com
Twitter: @EXAIR_TD

Even casual readers of the EXAIR Blog will notice that we Application Engineers are keen on efficiency. I just counted sixty-seven blogs on the site that discuss our Six Steps To Optimizing Your Compressed Air System. Some offer a broad overview, while others focus on specific steps, and one tells us more than I ever expected to learn from an engineering blog about…Bigfoot.

I’m going to take a different tack here – no; I’m not going to write about the Yeti or the Loch Ness Monster, but I may try to get the Jersey Devil into a blog someday. I will, instead, relate some real-life examples of the success of implementing each individual step. It’s important to note here that they don’t have to be done in order, or even in total, to achieve impressive results.

Measure the air consumption to find sources that use a lot of compressed air. Like I just said, you don’t HAVE to do these steps in order, but if you DO intend to pursue a comprehensive solution, this is where you want to start. The facility manager of a large manufacturing plant did just that when a series of Digital Flowmeters were installed in the branch lines to their production cells. By comparing their present-day actual usage to the original design specifications, they noticed that usage in a certain cell (due to business growth) had increased to the point that they had raised the main header pressure in an attempt to keep point-of-use pressures at proper levels. By installing a larger diameter branch line to that cell, they were able to reduce main header pressure from 120psig to 100psig, reducing their compressors’ energy usage (and their share of the electric bill) by 10%.

Summing Remote Display (left) for remote indication and totalizing data. USB Data Logger takes data from the Digital Flowmeter to your computer and outputs to its own software (shown above) or Microsoft Excel.
Find and fix the leaks in your compressed air system. A factory once noticed they were losing header pressure overnight, when they were closed. Using an Ultrasonic Leak Detector, they identified some small leaks that nobody thought were all that significant…until they did the math, comparing previous compressed air consumption (including those leaks) to that of their “new and improved” leak-free system. Fixing those leaks saved them just over a million cubic feet of compressed air a year. The exact figure was 1,062,500 cubic feet, annually. I know this is accurate, because it was us.
Upgrade your blowoff, cooling and drying operations using engineered compressed air products. This could apply to almost every single order we process, so I’m going use an example from my first day here. During training, I learned that a customer had recently called to get air consumption data on some EXAIR products they were going to implement as part of an upgrade that was also going to involve purchasing a new compressor. Their main usage was a number of open-end blow offs that ran continuously. After outfitting those with Model 1100 Super Air Nozzles and Model 9040 Foot Pedals (so the operators had simple, hands-free control over blowing cycles), they not only found they didn’t need a new air compressor, but were able to shut down an existing 50HP air compressor.

Foot Pedal + Air Hose + Super Air Nozzle = Instant Blow Off System!
Turn off the compressed air when it isn’t in use. There are a few methods for doing this, and they’re all pretty easy:
- Good. Manual shutoff valves (1/4 turn ball valves are great for this) can be used by mindful operators to shut off compressed air use between production cycles, during lunch breaks, and (I hope this is patently obvious to the most casual observer) at closing time. I’ve talked to users about doing this, but I don’t have any great success stories about this method. It relies on someone’s memory in knowing when to operate the valve…and nobody’s remembered to call me back with a full report either.
- Better. If you only need air blowing while a machine is running,
  
  EXAIR stocks Solenoid Valves in a variety of sizes & voltages
  
  most any qualified industrial electrician can wire a solenoid valve into the on/off control of the machine. Better yet, if the system has programmable logic control (PLC), it can be used to open & shut that same solenoid valve, to effect blow off only as needed. I worked with an automotive parts manufacturer who had a robot passing parts between a pair of Model 110042 42″ Aluminum Super Air Knives. They had taken care to accurately position the Air Knives, and program the robot’s movement & speed, to optimize blow off…but the Air Knives were running continuously. After a brief conversation with the line foreman, they bought and installed a Model 9065 1 NPT 24VDC Solenoid Valve and “told” the PLC to turn air flow on as the robotic arm approached the Air Knives, and turn it off right after the part had passed through.
- Best. In the absence of programmable logic, the simplicity of the EXAIR EFC Electronic Flow Control just can’t be beat. It’s a standalone system that consists of a Solenoid Valve that’s operated by a photoelectric sensor and controlled by a programmable timer. Whether it’s a tenth of a second, or a few minutes, waste is waste, and it adds up. Consider this application writeup from our Optimization Products catalog section:
  
  Turning air off when it’s not needed adds up, even if it’s just for a few seconds at a time.
Use intermediate storage of compressed air near the point of use. If

Prevent intermittent demands from starving other loads with intermediate storage.

compressed air is used in any sizable amount in your facility, odds are, you have a compressor room. If it’s done right, this is a good thing for your compressor, but it CAN present some challenges for distribution over large areas. A user of EXAIR Super Ion Air Knives, for example, installed a Model 9500-60 Receiver Tank in an area some distance from the compressor room to maintain higher air pressure than line loss (from the length of the header pipe) was allowing. Their other option was to increase their overall header pressure; this allowed them to maintain current costs…increasing system pressure by 2psi equates to a 1% increase in compressed air generation costs.
Control the air pressure at the point of use to minimize air consumption. In addition to controlling OVERALL compressed air system pressure (see examples 1 & 5 above), using Pressure Regulators to control the supply pressure to specific compressed air operated products will save you money too…the lower the supply pressure, the lower the consumption. A Model 1101 1/4 MNPT Super Air Nozzle, for example, uses 14 SCFM when supplied at 80psig…that’s where we publish its performance, because that’ll give a good, strong blast of air, suitable for a wide range of typical industrial air blowing applications. A tube manufacturer once replaced two open blow off devices that used about 38 SCFM each with Model 1101’s. Even though that cut their air consumption by more than half, they were able to cut it even further by regulating the supply pressure to 56psig…that’s the pressure at which they could still get the job done consistently, resulting in ANOTHER 25% reduction in compressed air consumption.