Super Air Knife Math – When 72 + 72 = 75

The Super Air Knife is the latest generation of EXAIR engineered air knife that dramatically reduces compressed air usage and noise when compared to other blowoffs.

Super Air Knife Data

From the chart above, the Super Air Knife when supplied with 100 PSIG of compressed air has a sound level of just 72 dBA (A-weighted decibel scale) when measured from 3′ away.  72 dBA is a moderate sound level, and some common comparisons are ‘normal speaking voice’ at 70 dBA and ‘living room music’ at 76 dBA.

For many processes, such as a bottling line drying operation, a pair of the air knives delivers the best performance. When asked, “what is the sound level for (2) of the knives,” a little Acoustic Engineering is in order. Because the decibel scale is logarithmic, the result is not as simple as adding 72 + 72 = 144.  144 dBA is in the range of a jet aircraft take off! Thankfully, both the actual sound level and the numerical value are determined another way.  I’ll spare you a lot of the math but the equation is as below.

Capture

… where SL1, SL2, SL3 are the sound levels in dBA of the each sound makers, for as many that are being combined.

In the case of (2) Super Air Knives operated 100 PSIG, the combined sound works out to be a quiet 75.0 dBA — a powerful, efficient and quiet product ideal for many applications and process within the manufacturing environment.

Super Air Knife

Super Air Knife

As a helpful rule of thumb- combining any (2) items will yield an increase of 3 dBA, combining (3) results in a rise of 4.8 dBA, and combining (4) results in a 6 dBA rise over just (1) of the items.

The Super Air Knives have been successfully used in a wide range of applications, including part drying, sheet and conveyor cleaning, web cooling, scrap removal, pre-paint dust blowoff, and many, many more.

To discuss your application and how an EXAIR Intelligent Compressed Air Product can make your process better and quieter, feel free to contact EXAIR and myself or one of our other Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

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Super Air Knives Make Beer Bottle Labels Stick; EFC Optimizes Efficiency

The Super Air Knife has been featured as the cover photo of every EXAIR Compressed Air Products catalog since I got here in 2011…except for Catalog #26 in 2013, which featured the Super Ion Air Knife. BIG difference, right there.

The highlighted application photos may change from catalog to catalog, but one that always remains is the iconic (I think, anyway) image of the Super Air Knives blowing off the orange soda bottles:

This is a darn-near ‘textbook’ application for the Super Air Knives…the even, laminar flow wraps around the bottles, stripping moisture away. Among other reason why this is important, it improves the next step in the process – the labels stick better.

One of the many simple and effective ways an EXAIR Super Air Knife is commonly used.

In my younger, intemperate days, I’d join my friends at a popular watering hole to celebrate special occasions like…well, Tuesday, for example. Sometimes, there’d be a ballgame on the TV, or lively conversation, to entertain us. Other times, we’d make a game out of trying to separate the labels from the beer bottles, in one piece.

Some years later, I tried to teach my young sons this game…except with root beer bottles. It didn’t work near as well, because these labels adhered much tighter to the root beer bottles in my dining room than the ones on the beer bottles at the bar.

Some years after that (those boys are teenagers now,) I became an Application Engineer at EXAIR, and found out that this drying-the-bottles-to-make-the-labels-stick-better thing was for real, because I got to talk to folks in the bottling business who told me that the Super Air Knives had made all the difference in the world for their operation.

Just the other day, I had the pleasure of helping a caller who operates a micro-brewery, and had just installed a set of 110009 9″ Aluminum Super Air Knives for the express purpose of (you guessed it, I hope…) making their labels stick better. The only thing that could make it better, according to them, was if they could use less compressed air, and they were interested in what the EFC Electronic Flow Control could do for them.

Click here to calculate how much you can save with an EXAIR EFC Electronic Flow Control.

As a micro-brewery, their production lines don’t run near as fast…nor do they want them to…as some of the Big Names in the business. As such, there’s some space between the bottles on the filling lines, and they thought that turning the air off, if even for a fraction of a second, so they weren’t blowing air into those empty spaces, would make a difference. And they’re right…it’s a simple matter of math:

Two 9″ Super Air Knives, supplied at 80psig, will consume 26.1 SCFM each (52.2 SCFM total). This microbrew was running two 8 hour shifts, 5 days per week. That equates to:

52.2 SCFM X 60 minutes/hour X 16 hours/day X 5 days/week X 52 weeks/yr = 13,029,120 standard cubic feet of compressed air, annually.  Using a Department of Energy thumbrule which estimates compressed air cost at $0.25 per 1,000 SCF, that’s an annual cost of $3257.00*

Let’s say, though, that the micro-brewery finds that it takes one second to blow off the bottle, and there’s 1/2 second between the bottles.  The EFC is actually adjustable to 1/10th of a second, so it can be quite precisely set.  But, using these relatively round numbers of 1 second on/0.5 seconds off, that’s going to save 1/3 of the air usage…and the cost…which brings the annual cost down to $2171.00*

*As a friendly reminder that the deadline to file our USA income tax returns is closing fast, I’ve rounded down to the nearest dollar.  You’re welcome.

That means that the Model 9055 EFC Electronic Flow Control (1/4 NPT Solenoid Valve; 40 SCFM) with a current 2017 List Price of $1,078.00 (that’s exact, so you know) will have paid for itself just short of one year. After that, it’s all savings in their pocket.

If you’d like to find out how much you can save with EXAIR Intelligent Compressed Air Products, give me a call.

Russ Bowman
Application Engineer
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Super Air Knife Cleans Rotary Mesh Screen

Last week I worked with an OEM who was looking for a more effective method of cleaning the wire mesh on the rotary screeners they manufacturer. Rotary screens, also know as trammel screens (think of a washing machine drum), separate solid materials by passing the parts through a rotating perforated cylinder, typically elevated on the feed side, to help keep the material moving through to the exit side. With the spiraling motion of the cylinder, the smaller parts begin to pass through the mesh screen, where they are commonly recovered in some type of hopper or fed onto a conveyor system.

Example of a screener/trammel used to separate gravel and sand.

In this particular application, their proprietary machine design features a non-vibratory system used in separating pet foods. The screener is working as far as separation but the problem they were having was as the pet food passes through the rotating mesh cylinder, it leaves an oily residue on the screen. Due to this being a food application, they are unable to use any type of cleaning brush over concerns that some of the fibers may break loose, contaminating the finished product, so they were looking at using air as an alternative solution.

I recommended they incorporate our 48″ Stainless Steel Super Air Knife in the application. The Super Air Knife is our most efficient unit, as far as compressed air usage, using only 2.9 SCFM per inch of knife when operated at 80 PSIG supply. The end to end, high velocity airflow produced by the unit would span the 48″ width of the screen. The top of their machine is removable, so I suggested they also incorporate our Model # 9060 Universal Mounting System. The Model # 9060 provides for an easy installation as well as a simple way to change the distance and direction of the knife to provide the most effective blowoff. With the cover off, they could easily move the knife into position to perform the cleaning.

Super Air Knife mounted to Universal Mounting System. (note: longer knives require multiple systems)

If you are considering an Air Knife to use in your process and would like to discuss the application, please give us a call at 800-903-9247.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

Trommel and sluicebox image courtesy of Roy Luck via Creative Common License

Slick Application for a Super Air Knife

A few weeks back I worked with a customer on an unusual application for one of our Air Knives. The company runs a camp, located in the North-Central part of the United States, complete with their own ski hill for skiing, snowboarding or tubing. They use a conveyor belt ski lift where the skier or snowboarder will stand on the belt and be transported back to the top of the hill for another run. They were starting to see some safety issues arise when the mat would get wet and freeze, causing the skiers to slip and fall back.

Photo of the ski belt conveyor

In an effort to remedy the situation, the installed a brush to try and help remove some of the snow and ice from the belt and while this helped a little, there was still moisture on the belt that would re-freeze. To aid in the drying process, they tried to use a floor blower aimed at the belt but the turbulent airflow seemed to “push” the water around rather than wipe it clean and dry. Out of ideas, they found EXAIR while doing an internet search and decided to give us call for assistance.

Further reviewing the details of the application, I recommended our 30″ Stainless Steel Super Air Knife for the application. The Super Air Knife provides an high velocity, laminar sheet of air across the length of the knife. The laminar flow from the air knife, would assure an even drying effect across the belt, rather than the turbulent flow from the blower. The stainless steel construction of the knife would hold up to the potentially harsh environmental conditions as well.

Super Air Knife available in aluminum, 303ss, or 316ss construction in lengths from 3″ up to 108″.

After some correspondence back and forth regarding air requirements and installation recommendations, the customer was able to source a rental compressor and ordered the 30″ Super Air Knife to test under our Unconditional 30 Day Guarantee. After a few weeks of testing, they were able to effectively dry the belt to an acceptable level, increasing the overall safety for their guests.

30″ SS Super Air Knife mounted under the belt on the “return” side.

 

Clever installation allowed for easy angle adjustment to ensure the airflow contacted the belt for optimal blowoff/drying.

EXAIR offers the quietest (69 dBA at 80 PSIG) and longest (up to 108″) Air Knives on the market today and we stock them in the most materials (aluminum, 303SS, 316Ss and PVDF) to best suit your application. To see how you might be able to utilize an Air Knife in your unique application, give us a call at 800-903-9247.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

 

 

 

Super Air Knives Used as a Non-Contact Barrier in a Non-Woven Application

An overseas customer manufactures a 2.2 meter wide non-woven material.  In one of their processes, the media would travel through a spray booth to apply a water-based surfactant.  The surfactant was atomized and blown onto the top and bottom of the material.  The spray booth was equipped with a fume hood to capture any excess mist.  The material would then travel out of the spray booth and into the oven to dry.

Area between Spray Booth and Oven

Area between Spray Booth and Oven

Because they were running at a speed of 160 m/min, a draft was being created as the media was exiting the spray booth.  This draft was strong enough to overcome the vacuum pressure from the fume collection system.  This would allow the excess mist to escape the spray booth.  It was then collecting on the surface of the oven and floor outside the containment area.  This created a safety issue as well as a large mess.

In looking at the problem area, the dimension of the opening of the spray booth was 2.65 meters by 300 mm.  To blow a good curtain of air to contain the mist, we needed to have a laminar flow to create that “wall”.  I recommended two pieces of a model 1102108 Super Air Knife Kits.  At 108” (or 2.74m) long, they are the longest Super Air Knives in the market.  With a steady flow of air along the entire 2.74 meter length, it can generate that curtain of air across the entire opening of the spray booth.  The laminar flow was key as they did not want to disturb the spraying nozzles inside the booth.

The Super Air Knife Kit also comes with a filter, a regulator, and a shim set.  With the included shim set, the force can be changed dramatically by using a different thickness of shim.  Since they did not need much force to keep the mist inside the spray booth, they opted to put a thinner shim inside the Super Air Knife.  This would reduce the amount of compressed air needed, and with a regulator, the customer could “dial” in the correct amount of force to create the proper air barrier.  The Super Air Knives were mounted above and below the material to blow directly across the opening of the spray booth.  Any fine mist that would come in contact with the air would be deflected back into the spray booth.  With the extra mist removed from the process, the fume extraction system could then perform its duties the way it was intended. With air being used to create that barrier, it did not disrupt the structure of the material or the surfactant on its surface.

Super Air Knife

Super Air Knife

If you require a non-contact barrier for your application, EXAIR Super Air Knives could be your solution.  For this customer, we were able keep the work place safe and mess-free.

 John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

Super Air Knives Replace Manifold Of Flat Nozzles, Saves Air, Saves Money

Last week I fielded a call from a steel plant who was using a manifold of 50 stainless steel, flat nozzles evenly spaced across a 130″ area, to blow off light scale and cooling water from steel sheets. The nozzles were working somewhat but they were seeing some “streaks” of scale and water remain after the initial blow off point. They were considering adding another manifold of nozzles as a secondary treatment but were concerned with the amount of air a setup like that would require, as well as the cost as each nozzle cost nearly $250.00 each. Operating at close to 80 PSI, they determined that each of the nozzles was using around 35 SCFM or roughly 1,750 SCFM for the manifold. Adding another manifold would obviously double that figure to 3,500 SCFM which would be a TON of compressed air to blow off water and light material.

Competitor Nozzle

Example of similar nozzle to what the customer is currently using.

After some further discussion, I recommended using (1) of our 60″ and (1) of our 72″ Stainless Steel Super Air Knives, coupled together, to provide a 132” laminar sheet of airflow. The laminar flow of air would be even across the entire 132″ length, eliminating any weak or dead areas like they are seeing with the existing setup, which is causing the streaking. The Super Air Knife uses only 2.9 SCFM per inch of knife when operated at the same 80 PSIG supply, so for 132″ of Super Air Knife, they would be using approximately 383 SCFM, much less than the current 1,750 SCFM, alleviating their concern for increased air demand. With the amount of air they would be saving, they could purchase the 60″ and 72″ Stainless Steel Super Air Knives, and the coupling kit to REPLACE their existing manifold system, eliminating the need of adding another manifold.

sak-coupled-together

Coupling brackets used to join Super Air Knives together end to end, providing a seamless, uninterrupted flow for wider than 108″ applications.

To discuss how an EXAIR product can help you decrease your air usage while providing superior results, contact one of our application engineers at 800-903-9247 for assistance.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

 

 

30′ Long Super Air Knife

Earlier this month, I got a call on a Wednesday afternoon from a gentlemen at a sawmill in the Pacific Northwest. He indicated that they had a saw machine that was 30′ long, and it had a special scanner system to detect problems with the cutting which ran the full 30′ length.  In a sawing operation, there is sawdust and chips, and they can adhere to any surface including the scanner window.  When the debris would build up, the scanner system would give off false detection signals and cause issues with the operation.  We discussed the Super Air Knives as a way to blow off the scanner window, and be able to cover the entire 30′ length.  He asked for a quotation for a 30′ long Super Air Knife (and that doesn’t happen very often!)  And oh, by the way, delivery was needed on Friday (in 2 days!)

EXAIR manufactures Super Air Knives in lengths up to 108″.  To get to 30′, we looked at using (3) 108″ and (1) 36″ length.  Due to the length, the 108″ have to ship by freight truck, while all of the other lengths can ship via UPS or Fed Ex.  Since the customer was needing an overnight shipment, we had to take this into account.

We settled in on a system of (6) 54″ and (1) 36″ Super Air Knife. An added benefit to this arrangement was to allow the individual control of operation of the units, with each length blowing for a short duration, on down the line, until each had cycled.  This kept the instantaneous air consumption to a reasonable level, instead of 1 very large demand for cleaning the whole 30′ at once.  A quotation was sent out Thursday morning.

bracket-sak-2

Coupling Bracket Kit – Used to Join (2) Super Air Knives

We received the order Thursday afternoon, shipped it later that day, and it delivered to the customer the next day on Friday. Installation occurred over the weekend.

The following Tuesday, I got an email – first to thank us for working so quickly from inquiry through to delivery for the 30′ of Air Knives, and then to ask to place another order for exactly the same set.  Turns out, there is a right edge scanner and a left edge scanner, and they were ready to do the other side.  We had a little extra time, and shipped out the full set a couple days later, and standard shipping still got to them before they were ready to install.

To discuss your application and how the EXAIR Air Knives can benefit your process, feel free to contact EXAIR and myself or one of our other Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

Send me an email
Find us on the Web
Like us on Facebook
Twitter: @EXAIR_BB

 

 

 

 

 

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