## Air Knife Shim Adjustment can be Key to Successful Applications

On January 2, 1960 Little Anthony & The Imperials appeared on The Dick Clark Saturday Night Beech-Nut Show to sing Shimmy Shimmy Ko Ko Bop. While I wasn’t around at that time, I have heard the song quite a few times and get it stuck in my head more than I have heard it. What does that song and EXAIR have to do with each other? Well, we shimmy shimmy Super Air Knives to dramatically increase or decrease their flow and force.

The stock shim that is assembled in every Super Air Knife is a .002″ (0.05mm) thick. This sets a continuous opening the full length of the knife that drives the performance of the knife. The shim sets the gap height between the cap and the body of the Super Air Knife. If we evaluate a 24″ Super Air Knife with the stock shim installed we could calculate the airflow opening of the knife as the surface area of a rectangle.  To obtain the surface area we take the length of the air knife times the thickness of the shim.  See the example below.

As you can see with the stock .002″ thick shim installed we are actually operating at a surface area opening of 0.048 square inches.  If we were to install the .004″ thick shim into the knife then we would double the height which in turn doubles the surface area, shown below.

This doubling effect will increase the force out of the Super Air Knife when applications require more power.  Thinning out the shim will have the exact opposite effect, if the shim thickness is reduced to .001″ thick then the air consumption and force will be reduced.

Changing the shims out of the Super Air Knives is a fairly simple task as shown in the video below.  Installing a different thickness of shim is a coarse adjustment to the volumetric flow needed for your application.  Then a pressure regulator can be used to fine tune the needed force and flow for the ideal setting to meet your needs, and operate at maximum efficiency for the application.

If you would like to discuss this further or even see what kind of custom thicknesses we can offer on the shims to truly make a tailor fit Super Air Knife for your application, please contact us.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

Little Anthony & The Imperials “Shimmy Shimmy Ko Ko Bop” – [Merlin] XelonEntertainment, WMG (on behalf of Turntable Recordings LTD); ARESA, LatinAutor, União Brasileira de Compositores, Spirit Music Publishing, UNIAO BRASILEIRA DE EDITORAS DE MUSICA – UBEM, Abramus Digital, BMI – Broadcast Music Inc., and 4 Music Rights Societies – https://www.youtube.com/watch?v=5mLjZRAXRRA

## Super Air Knives in Agriculture

I spoke with an international agribusiness that specialized in improving processes with cutting-edge technologies in the agricultural sector.  They started a project with a company to improve their drying process for potatoes.   This company was washing 10 tons of potatoes per hour during 16-hour days.  The potatoes would travel along a conveyor that was 90cm (35.4”) wide after the washing system where they had three blower air knives to remove the water from the surface.  Since the project scope was to increase productivity, the agribusiness company targeted their biggest issue, the blower air knives.

They described the two main problems that their customer was experiencing.  First, the conveyor had to run at a slower rate to remove enough water from the surface of the potatoes before packaging.  Thus, the feed rate into the washing system ran intermittently to not overload the drying process.  The main issue was that the blower system was limited with force.  It could not generate a strong enough air stream to properly dry the entire spud at higher speeds.  Thus, the conveyor system was not at an optimal range.

The second issue was premature spoilage of the potatoes which had to be discarded.  I remember when my family would store potatoes in bunkers under the ground to keep them cool.  This would help to slow the bacterial growth which causes spoilage.  Blower systems generate hot air from the electric motors.  Since bacteria growth is enhanced with warmer temperatures, the potato company was noticing poor appearance and early spoilage.  To increase their profits, they wanted to dry the potatoes without heat.

EXAIR has been manufacturing leading-edge technology since 1983, and we could offer a solution.  For removing water from the surface of the potatoes; the EXAIR Super Air Knife would be the perfect instrument.  This compact system is easy to install; and it does not have any moving parts to wear or need shutdowns for maintenance.

I recommended to replace the three blower-air knives with one piece of a model 110236SS Super Air Knife Kit.  The kit includes a 36” (914mm) 303SS Super Air Knife, a filter, a regulator and a shim set.  The regulator and shim set are specifically designed to control the force requirement and air usage to the Super Air Knife.  So, you can fine tune the correct amount of force to blow around the entire potato for effective drying.  For a stock Super Air Knife, the model 110236SS can generate 5.6 pounds of force (2.55 Kilograms) at 80 PSIG (5.5 Bar); a tough target for a blower air knife.  The agribusiness was excited about the concept and wanted to know more.

Another unique feature with the EXAIR Super Air Knife is the engineered design.  We are able to reach a 40:1 amplification ratio.  That means for every 1 part of compressed air, we can entrain 40 parts of ambient air.  What does this mean?  First, the Super Air Knife is very efficient within your compressed air system as we are using mainly free ambient air.  Second, since majority of the air is ambient, the temperature of the air is not heated; thus, a cooler air stream.   And third, by adding the mass of the ambient air, it gives a stronger blowing force.  So, the Super Air Knife was able to meet both of the agribusiness requirements.  In the end, we were able to cut scrap and increase the production rate by almost 10%.

If you need to dry your agricultural items with cutting-edge technology, EXAIR would be the manufacturer for you.   We are staffed with Application Engineers to find solutions and improvements, and we will be happy to discuss your application.  For this agribusiness company, they were excited to work with EXAIR to get a great result for the company above in the potato arena.

John Ball
Application Engineer
Email: johnball@exair.com

## Proper Plumbing Prevents Poor Performance

There’s nothing quite like an ice-cold Coke from McDonald’s. While there’s many reasons for this, one of the reasons for the unique experience of a McDonald’s Coke lies in the straw itself. In their drinks, they provide wider straws that are designed to help enhance the taste of Coca-Cola, or so they claim. Another impact of this is it allows you to drink significantly faster. The wider the opening for liquid to pass through, the more volume you’re able to drink. Imagine trying to drink your Coke, or any other beverage, through a coffee stirrer. I imagine you’re going to have a difficult time and a dry mouth as you try and force what little amount of liquid you can through the small I.D. of a coffee stirrer. Try that with a milkshake and the problems compound…..

The same is true when it comes to plumbing of your point-of-use compressed air products. I recently assisted a customer that was experiencing lackluster performance from the Super Air Knife they purchased. The application was fairly straightforward, they were hoping to reduce the rate of rejected material on their production line of plastic sheets. The sheet goes through a washing process to remove any residual contaminants, then would air dry as it made its way down the line. As the material dried, there were water spots left on the material that would have to then be cleaned off. In the hopes of speeding up the drying process, they purchased a Model 110060 60” Super Air Knife to provide a wide laminar sheet of air to dry the material.

When they hooked everything up, the flow from the knife seemed far less than they were expecting. They were supplying full line pressure (just over 90 PSIG), so in theory they should feel a strong blast of air from the knife. When they installed a pipe tee and pressure gauge directly at the inlet, they noticed the pressure was dropping to 35 PSIG while the knife was in operation. When this occurs, it’s indicative of a lack of volume of air. This can be caused by undersized compressor,  or improper plumbing. In their case, they were only plumbing compressed air to one center inlet of the knife. For a 60” knife, EXAIR recommends a minimum of (4) air inlets to ensure adequate volume.

The size of these lines is also critical. You can’t force greater volumes of air through a smaller hose or pipe, just like you can hardly drink through a coffee stirrer with any great success. A 60” knife requires a supply pipe size of 1-1/2” for up to a 50’ run, if you’re trying to supply a knife of this length with a 100’long, ¼” ID hose, you’re not going to get the performance you expect. If you’re experiencing less than optimal performance from any of your EXAIR Intelligent Compressed Air Products, there’s a good chance air supply is the culprit. The first step is determining what the actual inlet pressure is, install a pipe tee and pressure gauge right at the inlet. Then, give us a call and we’ll help work through the proper line sizes and ensure that you’re getting the most out of our products.

I hope I didn’t make you hungry or thirsty… But I think I know where and what I’m having for lunch 😊!

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

## Next Level Customer Service

I recently spoke with a customer who is a casting / machining manufacturer.  They had an automated cell that was finish machining a feature on a cast aluminum part then placing it on a conveyor belt for an operator to pick up and continue processing.

The parts were placed 3 pieces wide per row and the conveyor would index with every three parts.   The operator would pick three pieces up and transfer them to another station during the machining time.  These parts were carrying residual machining coolant and debris onto the outbound conveyor.

The operator would blow them off with a handheld blow gun and all the coolant and chips would generally end up on the floor in the area causing a slip hazard.  The focus of the project is to eliminate the safety hazards and leave the parts as clean as possible for the inspection and further process.

The metal parts were positioned similar to the parts I placed in the mock up picture below.  The conveyor the customer has is an open mesh conveyor so the process will work better than if it was a solid belt like in the mock up.

The bulk of the concern from the customer was the outside of the part and they stated that anything to blow out the internal is a bonus.  The objective is to get as much coolant off as possible.   For that we recommended they span the conveyor with a Super Air Knife Kit to blow all the parts off at once.  This is mounted closely in the mock up because the customer had space restrictions.

Then, because the parts are always placed in the same location with the same orientation we can locate the ID hole with a Mini Super Air Nozzle on a Stay Set Hose of varying length to reach each set of parts as they come through.  Once I had the idea and the products in place I delivered the customer  a quote and dimensional CAD file for each part.

Another recommendation was to use a regulator and filter to control just the knife then operate the three nozzles off their own regulator and filter so that the forces between the two can be varied and the performance of the other is not effected.  Accompanying the models were installation sheets for each item as well.   Followed by the pictures of this mock up for their application.

Needless to say the customer was amazed that we would go to such lengths just to give them more assurance than our 30 day guarantee.  They were extremely thankful and are pleased we shipped from stock and met their installation window.

If you are looking for a creative solution, next level customer service, same day product availability, or just a nice human to talk to about compressed air, contact us.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

## Super Air Knives Save 63% Electrical Cost for a Food Manufacturer Drying Trays

A food manufacturing company was looking for a more efficient way to dry polypropylene trays that were filled with food product. With their current operation, they would send already packed and sealed food trays through a washing system that used sterilized water. The trays would then have to be dried prior to bulk packaging. The operators would place the trays side by side on a 24” wide open-mesh stainless steel metal conveyor with two or three trays at a time (depending on the tray dimensions). They contacted EXAIR because they wanted to replace their “old and inefficient system” with something better.

In my discussions, they gave some additional details of the operation and the problems that they were seeing. The dimensions of the trays ranged from 150 to 200mm long by 100 to 150mm wide by 35 to 50mm in height. They were cleaning at a rate of 30 trays per minute through the washing and drying system. The washer was designed to recycle the water to improve “green” operations. But the trays were carrying much of the water outside the machine. Thus, they would have to stop and refill the wash system with fresh water.

After the washing cycle, the drying section began. It consisted of two parts; a sponge roller and a heated chamber that would blow hot air. First the trays would run under the sponge roller to absorb the water from the top of the trays. A feature that they did not like was the continuous adjustment to the sponge roller for the different tray heights. They had to make sure that they had good contact without stopping the movement.

Also, with bulk of the water being on top of the trays, the sponge surface would get saturated. They would have to stop the process to change with a dry foam pad or replace due to wear. After the sponge roller, it would move into a heated chamber to remove the remaining portion of the water from the trays. They used a 11 KW heating system to blow hot air. This part of their system required a lot of electricity to run. They wondered if EXAIR could help streamline their process and reduce energy costs.

They sent a photo of their system, reference above. As described, the trays were moving intermittently through the wash cycle and then into the drying operation. When gaps are present in a process, the Electronic Flow Control, or EFC, becomes a great product for energy efficiency. It is designed to use a photoelectric sensor to detect a part and initiate a timing sequence. Using a solenoid valve, it will turn on the compressed air only when needed. With the drying operation, I suggested that they could remove the sponge roller and heated chamber, and replace them with two Super Air Knives. In conjunction with the EFC, we can decrease energy usage, reduce downtime, and increase savings. Profit margins can be critical in the food industry, and EXAIR has many ways to help.

To expand a bit more about revitalizing the “old and inefficient system” with EXAIR products, I made some suggestions. I recommended two Stainless Steel Super Air Knife Kits, model 110224SS, to be placed near the end of the conveyor. One Super Air Knife would be positioned above the tray to blow across the top; and one would be positioned below the tray under the mesh conveyor to blow across the bottom.

At a slight blowing angle in a counter-flow direction, the air streams would remove the water from the top and bottom of the tray at the same time. This would create a non-contact “wiping” solution. Now they do not have to worry about parts wearing out due to contact. Another unique feature of the Super Air Knife is the strength of the laminar air stream. It is consistent from 3” (76mm) to 12” (305mm) away from the target. Thus, they can easily set the height of the Super Air Knives to dry all the different trays without adjusting it.

And as an added benefit, the water that was being blown off the trays by the Super Air Knives remained within the washing system. The sterilized water was not being wasted and could be recycled. With the Electronic Flow Control, I recommended the model 9056. It is a user-friendly device with eight different timing sequences. They were able to position the photoelectric sensor near the outlet of the washing system. As soon as the trays were detected, the Super Air Knives would turn on to blow two or three trays at the same time. With the EXAIR products installed, the system went from using 11 KW down to 4 KW, a 63% savings.

EXAIR has helped many customers like this one above. When it comes to energy savings, EXAIR leads the way. With two Super Air Knives and an EFC, we were able to modernized their system; save on water, improve productivity, reduce the overall footprint, and save on their energy usage. If you have a similar application, you can contact an Application Engineer at EXAIR. We will be happy to update your system.

John Ball
Application Engineer
Email: johnball@exair.com

## EXAIR Standard Air Knife Keeps Bottles Free From Contaminants

Recently I worked with a customer on an application to remove contaminants from the inside of glass bottles. During production, dust from the ambient environment was collecting inside of the bottles. They needed a way to remove it prior to filling. The solution was to briefly pause the conveyor, pulsing air into the bottles to free any dust that had accumulated. Their problem was that while the dust was blowing out of the bottle without an issue, some of it was settling back down into the bottles.

The customer needed a way to mitigate the risk of dust particles resettling into the bottles after it was removed. The solution was to install a Model 2012 12” Standard Air Knife to provide a curtain of air across the top of the bottles, catching any freed dust particles and blowing them away from the conveyor.

After noticing positive results, we wanted to take things one step further and help to reduce overall air consumption in the process. The blowoff was achieved with (8) ¼” open tubes operating at a pressure of 80 PSIG. Although they were only operating for a fraction of a second, they still consume a whopping 33 SCFM! Replacing them with Model 1101 ¼” NPT Super Air Nozzles (14 SCFM at 80 PSIG) resulted in compressed air savings of 58%!!

In addition to saving compressed air, the noise level was also dramatically reduced. At just 74 dBA, we’re below the threshold for an 8-hour exposure time for operators according to OSHA. Where earplugs were necessary before, they’re now able to operate safely without the need for PPE to protect their hearing. The second most effective fundamental method of protecting workers, according to NIOSH, is to substitute or replace the hazard with an engineered solution. It’s not possible to eliminate the hazard as a compressed air blowoff was necessary, but the next best step is to replace it with something safer.

In addition to complying with OSHA 1910.95(a), the Super Air Nozzle also cannot be dead-ended. In applications for compressed air blowoff with unsafe nozzles, pipes, or tubes, the pressure must be regulated down to below 30 PSIG according to OSHA 1910.242(b). The installation of an engineered compressed air nozzle by EXAIR allows you to operate safely at much higher pressures.

If you have inefficient blowoff processes in your facility, give one of our Application Engineers a call. We’ll be happy to take a closer look at your application and recommend a safe, reliable, engineered solution!

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

## How to Install A Super Air Knife – From the Basic to the Creative

Occasionally, a caller will ask if we offer installation services for our products. They’re usually very pleased to learn that there’s not all that much to it.

Any of our Super Air Knives can use our Model 9060 Universal Air Knife Mounting Systems (shown below; one on a 12″, and four on a 108″ length) for easy installation and precise aiming.

Shorter lengths, like the Model 110006 6″ Aluminum Super Air Knife (below, left,) can be adequately supported by air supply piping.  We don’t recommend that with longer lengths (due to overhung load concerns) but even a Model 110018 18″ Aluminum Super Air Knife (below, middle,) can be supported by the supply pipe in a vertical position.  We even stock our 3″ Aluminum Super Air Knives with Stay Set Hoses & Magnetic Bases (below, right.)

The Super Air Knife also has a series of 1/4″-20 tapped holes, 2″ apart, along the bottom of the body.  These are often used for installation & mounting as well, and we’ve seen some creative methods, for sure:

EXAIR Super Air Knives come in lengths from 3 inches to 9 feet long.  We stock them in aluminum, 303SS, 316SS, and PVDF.  If you need a custom length or material, though, we do those too.  We can even talk about the best way to mount it.  Call me.

Russ Bowman
Application Engineer
EXAIR Corporation
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