## How to Calculate the Cost of Leaks

Leaks are a hidden nuisance in a compressed air system that can cause thousands of dollars in electricity per year. These leaks on average can account for up to 30% of the operation cost of a compressed air system. A leak will usually occur at connection joints, unions, valves, and fittings. This not only is a huge waste of energy but it can also cause a system to lose pressure along with lowering the life span of the compressor since it will have to run more often to make up for the loss of air from the leak.

There are two common ways to calculate how much compressed air a system is losing due to leaks. The first way is to turn off all of the point of use compressed air devices; once this has been complete turn on the air compressor and record the average time that it takes the compressor to cycle on and off. With the average cycle time you can calculate out the total percentage of leakage using the following formula.

The second method is to calculate out the percentage lost using a pressure gauge downstream from a receiver tank. This method requires one to know the total volume in the system to accurately estimate the leakage from the system. Once the compressor turns on wait until the system reaches the normal operating pressure for the process and record how long it takes to drop to a lower operating pressure of your choosing. Once this has been completed you can use the following formula to calculate out the total percentage of leakage.

The total percentage of the compressor that is lost should be under 10% if the system is properly maintained.

Once the total percentage of leakage has been calculated you can start to look at the cost of a single leak assuming that the leak is equivalent to a 1/16” diameter hole. This means that at 80 psig the leak is going to expel 3.8 SCFM. The average industrial air compressor can produce 4 SCFM using 1 horsepower of energy. Adding in the average energy cost of \$0.25 per 1000 SCF generated one can calculate out the price per hour the leak is costing using the following calculation.

If you base the cost per year for a typical 8000 hr. of operating time per year you are looking at \$480 per year for one 1/16” hole leak. As you can see the more leaks in the system the more costly it gets. If you know how much SCFM your system is consuming in leaks then that value can be plugged into the equitation instead of the assumed 3.8 SCFM.

If you’d like to discuss how EXAIR products can help identify and locate costly leaks in your compressed air system, please contact one of our application engineers at 800-903-9247.

Cody Biehle
Application Engineer
EXAIR Corporation
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## EXAIR Super Air Knives: Customized for You

In a recent blog “EXAIR Super Air Knives: Overview”, I shared the features and benefits that puts the “Super” in the Super Air Knives.  But, let’s not define ourselves by our widest range of lengths and materials that we stock.  EXAIR can also customize the Super Air Knives to fit your requirements.  Many manufacturers like to make their standard items and expect the customers to adapt to their design.  But at EXAIR, customer service is our primary focus.

EXAIR manufactures our products at one location in Cincinnati, Ohio.  So, this gives us the flexibility to do many things like making adaptive configurations with our Super Air Knives.  Here are some examples that our customers requested.

• Special lengths: EXAIR stocks standard incremental lengths from 3” (76mm) up to 108” (2.74 meters) in aluminum, 303SS, and 316SS materials; or 3” (76mm) to 54” (1,372mm) for PDVF Super Air Knives. But sometimes, the Super Air Knife has to fit into a specific area where a standard length will not work.  This is where EXAIR exceeds, and we can make any length metric or imperial between the ranges above.

• Other materials: There isn’t a single material that is inert to all chemicals. In some rare cases, the environment can chemically attack our Stainless Steel or PVDF Super Air Knives.  So, a different material may have to be used.  For the customer above, they required a PVC material for a phosphorous environment.

• Critical Dimensions: When the Super Air Knives have to adapt inside machines or in tight areas, we can modify the profile.  We have two special applications (reference above) that needed a design change for fit and function.  A curved Super Air Knife was used to hold tubes on a rotary table; and a thin Super Air Knife that was only 11/16” (17.5mm) thick cleaned a mold for circuit chips.

• Add-ons: EXAIR understands the importance of connecting to our Super Air Knives to get the greatest performance.  Our stock product has ¼” NPT inlet air ports along the bottom and one at each end.  We have ¼” – 20 threaded holes for mounting along the bottom as well.  But if you want threaded holes in a specific location for mounting or need the inlet air ports to be metric threads, EXAIR can accommodate these features.

• Situational Applications:  Super Air Knives can have complex or simple changes depending on the application.  As an example, EXAIR created a design for a double-sided Super Air Knife to blow a laminar stream of air 180 degrees apart (reference photo above).   A simpler proposal was to replace the cap screws in a 316SS Super Air Knife with hygienic screws for food applications to remove crevices for bacterial growth.
• OE Protection: In today’s market, it is important to protect your business.  At EXAIR, we can make a special Super Air Knife to blow, dry, or cool in your custom machines.  With a unique model number, EXAIR can help support and protect your business for future and replacement business.

Remember, your imagination is the beginning of creation.  If you cannot find a specific design to be used in your compressed air application, don’t give up.  Contact an Application Engineer at EXAIR to see if we can help you.  We have a team of engineers that can evaluate the fit and function to create a “Super” blow-off solution.  For the customers above, we were able to propose a unique Super Air Knife to work in their application; not the other way around.

John Ball
Application Engineer
Email: johnball@exair.com

## Save Thousands of Dollars – Just Like You Did When Upgrading Your Light Bulbs

The cheapest and easiest solution isn’t always necessarily the best. The best example I like to use to highlight this is the incandescent light bulb. They’re definitely the cheapest to buy, but over the useful life it will cost more in electricity to operate and it won’t last nearly as long as an LED light bulb. When you compare the costs of electricity as well as the lifespan of an incandescent bulb, it becomes quite clear that the initial price difference between the two will be quickly recouped over the lifetime of the LED bulb. Once it pays for itself, it doesn’t just stop saving you electricity. These savings continue to compound.

The same can be said when comparing the Super Air Knife to a commonly seen homemade alternative, drilled pipe. While it only takes a matter of minutes to drill a few holes into a section of pipe, the operating costs (electricity required to generate the compressed air) are significantly higher than that of the Super Air Knife. In addition, it’s not nearly as effective and is considered unsafe under OSHA 29 CFR 1910.242 (b) and depending on operating pressure is likely also considered dangerous due to the high sound levels as outlined in OSHA 29 CFR 1910.95(a).

Air exiting out of drilled holes in a pipe will create a turbulent airstream. This turbulence not only contributes to the high sound level but it’s ability to entrain surrounding ambient air is minuscule. The air entrainment ratio of a compressed air solution refers to the relationship between supplied compressed air and the free ambient air that is brought into the primary airstream. The higher the amplification ratio, the less compressed air necessary to complete a similar task. For a drilled pipe, the amplification ratio is generally around 3:1. With the Super Air Knife, this is dramatically increased with an amplification ratio of 40:1.

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.

Once the knife has paid for itself, it doesn’t just simply stop saving you money. That savings continues to compound and add to your bottom line. Don’t waste unnecessary air (and money) by using solutions that aren’t engineered to do the job in a safe and efficient manner. Reach out to an Application Engineer and get yourself an Intelligent Compressed Air Product that’s Built to Last.

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

Light bulb photo courtesy of Pixabay.

## Webinar by EXAIR: Use This, Not That – Four Common Ways to Save Compressed Air in Your Plant

Not much in life is free anymore. So, make sure and take advantage of EXAIR’s upcoming FREE webinar at 2:00 PM ET on 10/17/2019. Not only are we providing it for free, but in this webinar we’ll be discussing how you can save money by reducing your compressed air consumption. Something for free, that will help save you money? Almost unheard of these days!!! Hosted by one of our highly-trained Application Engineers, Jordan Shouse, you’ll learn about four common ways that you can easily save air in your facility.

Compressed air is often referred to as the fourth utility in industry. When used improperly, compressed air is extremely expensive. Homemade devices such as open-ended and drilled pipes, inefficient air nozzles, leaks, etc. all contribute to increased energy costs. In addition to being wasteful, these devices are not safe and compliant with OSHA standards and regulations. By using an Intelligent Compressed Air Product, you’ll be both saving money and creating a safer environment for your operators.

In this webinar, you’ll gain an understanding of the places in your facility that are wasting the most compressed air. We’ll educate you on the various engineered solutions available from EXAIR to help eliminate unnecessary compressed air usage. You’ll gain the knowledge necessary to determine the best solution based on the application, sound level, compressed air usage, and compliance with OSHA safety requirements. You’ll also learn about the various solutions available to help understand and optimize your compressed air system. You can’t begin implementing a plan to reduce air consumption until you fully understand the usage in your own facility and processes. EXAIR’s line of Optimization products are ideal to help you gain a baseline measurement and begin implementing new products and processes that’ll only help add to your bottom line.

After the conclusion of the webinar will be a brief Q&A session where you can ask any questions you have about any of the topics covered. Unable to attend the webinar live? Don’t let that stop you from registering! Afterwards, each registrant will receive a link via e-mail where they’ll be able to access the full webinar at any time. Make sure and take advantage of this opportunity to gain some knowledge about the usage of your compressed air. You’ll be glad you did!

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