Opportunities To Save On Compressed Air

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.

  1. 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.
  2. 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.

  3. 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!
  4. 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.

       

       

       

  5. 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.
  6. 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.

If you’d like to find out more about any, or all, of the Six Steps To Optimizing Your Compressed Air System, give me a call.

Russ Bowman, CCASS

 

 

 

Application Engineer
EXAIR Corporation
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Find Compressed Air Leaks with an Ultrasonic Leak Detector

The Ultrasonic Leak Detector (ULD) is a hand-held, high quality instrument that can locate costly leaks in a compressed air system. The definition of Ultrasonic as defined by Merriam-Webster is: “having a frequency above the human ear’s audibility limit of about 20,000 hertz —used of waves and vibrations.” The human hearing range depends on pitch and sound. Sound is a measure of how low or high the volume of loudness in terms of decibels (dBA) and “Pitch” is measured in Hertz (Hz).The overall spectra of the emitted ultrasonic sound is “white noise”, white noise is the broad band emission of sound.

Humans can detect sounds in a frequency range from about 20 Hz to 20 kHz. (Human infants can actually hear frequencies slightly higher than 20 kHz, but lose some high-frequency sensitivity as they mature; the upper limit in average adults is often closer to 15–17 kHz.)

The Model 9061 ULD is designed to locate the source of ultrasonic sound emissions and is used to find compressed air leaks. These ultrasonic sound emissions are converted by the ULD to a range that can be heard by humans. All this being said, the EXAIR ULD makes finding your air leaks fast and efficient.

The Model 9061 comes complete with with a hard shell plastic case, headphones, parabola, tubular adapter, tubular extension and a 9 volt battery. The ULD can be adjusted to filter out background noise typically heard in manufacturing environments by using the X1, X10 and X100 sensitivity settings. The “on/off” thumb wheel can be used for sensitivity adjustment within each of theses settings. The parabola or tubular extension can be attached to the ULD masking out background noise and finding the ultrasonic sounds being generated from the leaks.

Compressed air is an expensive cost center so using the ULD to detect and fix air leaks can not only be fun but also show a payback on investment with just one leak detection. The illustration below demonstrates just how a payback occurs.

EXAIR has many tools and accessories for your intelligent air needs and want to hear from you as we have Application engineers ready to assist your projects and compressed air challenges.

Eric Kuhnash
Application Engineer
E-mail: EricKuhnash@exair.com
Twitter: Twitter: @EXAIR_EK

Installing Secondary Receiver Tanks: Step 5 in Optimizing Your Compressed Air System

SixSteps

The 5th 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. Secondary, or intermediate 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.

receiver_tank

They can be strategically placed to provide a source of compressed air to intermittent high volume compressed air applications. Rather than having to pull from the compressor, a receiver tank can be sized to provide the short-term volume of air for a particular application. In a previous post, we’ve highlighted how to calculate the necessary receiver tank based on the air consumption and duration of the application.

EXAIR offers from stock a 60-gallon receiver tank designed specifically for these higher-usage intermittent types of applications. Model 9500-60 can be installed near the point of high demand so that you have an additional supply of compressed air available for a short duration. The tank comes with mounting feet and is designed to stand up vertically, saving floor space. The tank meets American Society of Mechanical Engineers (ASME) pressure vessel code.

If you have an application in your facility that’s draining your compressed air system, a receiver tank could be the ideal solution. Give us a call and one of our Application Engineers will be happy to help evaluate your process and determine the most suitably sized receiver tank.

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

Does a 38 Day Simple ROI Sound Good? Use Engineered Compressed Air Blowoff Products!

After getting a baseline measurement of the air consumption in your facility 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.

sixsteps_3

This step can have the most impact when it comes to your bottom line. The energy costs associated with the generation of compressed air make it one of the most expensive utilities for any industrial environment. Because of this, we need to ensure that the places in your facility that are using compressed air are doing so efficiently.

EXAIR manufactures a variety of products that can help to ensure you’re using your compressed air in the best way possible. What 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. Super Air Nozzles have been designed to entrain ambient air along with the supplied compressed air, allowing you to achieve a high force from the output of the nozzle while keeping compressed air usage to a minimum. In addition to saving air, they’ll also provide a significant reduction in overall sound level.

drilled pipe
homemade drilled pipe

Another product that can be used to increase the efficiency of your blowoff processes is the Super Air Knife. Available in lengths ranging from 3”-108” and in a variety of materials, the Super Air Knife is the ideal replacement for inefficient drilled pipes. Again, it may seem cheaper to just drill a few holes in a pipe whenever you need to cover a wide area but the volume of air consumed in addition to the incredibly high sound level will quickly drain your compressor. The Super Air Knife is also designed to entrain ambient air, at a rate of 40:1! Allowing you to take advantage of the free ambient air in addition to the supplied air.

Let’s compare the costs difference between a homemade drilled pipe and EXAIR’s Super Air Knife. The Super Air Knife has a precisely set air gap across the full length of the knife, allowing for an efficient and quiet laminar airstream. When compared to a drilled pipe, the air consumption is dramatically reduced as is the sound level. For example, let’s take an 18” section of drilled pipe, with 1/16” diameter holes spaced out every ½”. At 80 PSIG, each hole consumes 3.8 SCFM. With a total of 37 holes, this equates to a total of 140.6 SCFM.

3.8 SCFM x 37 = 140.6 SCFM

A Super Air Knife, operated at 80 PSIG with .002” stock shim installed will consume a total of 2.9 SCFM per inch of knife. An 18” SAK would then consume just 52.2 SCFM.

2.9 SCFM x 18 = 52.2 SCFM

140.6 SCFM – 52.2 SCFM = 88.4 SCFM saved 

Replacing an 18” drilled pipe with a Super Air Knife represents a total reduction in compressed air consumption of 63%! How much does this equate to in $$$? A reasonable average of cost to generate compressed air is about $0.25/ 1000 SCF. Let’s assume just a 40hr workweek:

88.4 SCFM x 60 mins x $0.25/1000 SCF = $1.33/hr

$1.33 x 40hr workweek = $53.20 USD

$53.20 x 52 weeks/year = $2,766.40 USD in yearly savings

The 2019 list price on a Model 110018 Super Air Knife is $397.00. By replacing the homemade solution with an 18” Super Air Knife, the return on investment is just over 38 working days of an 8-hr shift. If your plant runs multiple shifts, or works on weekends, it pays for itself even quicker.

Not only are these homemade solutions expensive to operate, they’re not safe either. Familiarize yourself with both OSHA 29 CFR 1910.95(a) and 29 CFR 1910.242(b) and you’ll learn just how expensive it can be if you were to be found using these devices during a random OSHA inspection. Make sure you’re utilizing the most expensive utility as efficiently and safely as possible. If you need help with determining which products are best suited for your application, give us a call. Our team of Application Engineers is ready to help!

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