Combining Products For Total Blow Off Of Objects With Complex Geometry

EXAIR Super Air Knives are extremely efficient at blowing off flat surfaces. The laminar air flow they generate makes a stripping/sweeping action, as opposed to the turbulent flow from a non-engineered blow off, which really just beats on the surface. If the object being blown off, though, has features such as holes, recesses, grooves, bosses, “nooks & crannies”, etc., it may be challenging to get those features 100% blown off, 100% of the time.

If the object you’re blowing off is flat, the laminar air flow from a Super Air Knife is ideal. They come in lengths from 3 inches to 9 feet long.

Depending on the size & shape of the feature presenting the challenge, the first thing we might recommend is to adjust the angle at which the Air Knife’s flow contacts the surface. For most applications, you can optimize performance by blowing at as low of an angle as practical. You may need to aim the Air Knife at a steeper angle, for example, if you’re blowing off something that’s dense (like shot blast or garnet, as opposed to dust or chips), or if it’s somewhat adherent to surface (like grease or mud, as opposed to water or light oil). This can also work if you’re trying to blow out a hole, recess, or groove in an object.

EXAIR manufactures a wide variety of engineered Air Nozzles, designed for safety, efficiency, and quiet operation.

Other times, a dedicated blow off may be necessary to pick up where the Air Knife leaves off. In situations like that, we can specify an appropriately sized Air Nozzle, Air Jet, Air Amplifier, or maybe even a smaller Air Knife, to provide more complete removal of whatever you need to get off of the object. It’s fairly common to use Air Nozzles for these applications, and our Air Nozzles & Jets catalog section is a great tool that can be used for selection. It lists them all, from smallest to largest, with airflow patterns, performance data, and dimensions.

EXAIR offers solutions for plumbing, installation, and aiming the Air Nozzle too:

  • Swivel Fittings are installed on threaded pipe, and provide 50° of angular movement. Just loosen the lock nut, aim the Nozzle, and re-tighten for rigid & secure placement.
  • Stay Set Hoses are likewise be threaded into 1/4 FNPT connections, with the Air Nozzle secured onto the other end. These come in lengths from 6″ to 36″, with 1/8 FNPT or 1/4 MNPT threads for the Air Nozzle.
EXAIR Stay Set Hoses and Swivel Fittings are ideal for installation and positioning of your Super Air Nozzle.

Metal tubing with compression fittings is another option, that can be used to install & aim an Air Nozzle. Copper tubing is relatively easy to bend by hand. Stainless steel tubing usually requires a tube bender tool, with the advantage that it can’t easily be bent by hand…on purpose or by accident. While metal tubing is certainly an option, it is generally reserved for applications where the ability to readjust is not necessary. The Stay Set hoses and Swivel Fittings tend to work better when flexibility is required.

The copper tube used to have a crimped end that was aimed at the part in the chuck. They simply cut it off and used a compression fitting to install the Super Air Nozzle.

If you’ve got a blow off application that’s not working the way you want it to, it’s highly likely that EXAIR has a solution. We would love to share our ideas with you. Give me a call.

Russ Bowman, CCASS

Application Engineer
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Optimizing Your Compressed Air Usage With Engineered Products

The first new car I ever bought was a 1995 Ford Escort Wagon. I’ve mentioned this before in posts about preventive maintenance, the importance of proper filtration, and brand loyalty. Those blogs were primarily about my experiences with that little red wagon, but today I wanted to discuss the primary reason I bought the car in the first place.

I had a 50-mile round trip commute to work, and my old Pontiac Grand Prix with the small block V8 engine was a great ride for sure. Some quick math, however, showed that if I went with something with better gas mileage, I could save quite a bit of money on gasoline. My calculation was almost $1,000 a year, just on driving back & forth to work. After figuring in the rest of my driving for the first year, it was more like $1,400 a year.

Similar to my “upgrade” to a more fuel efficient vehicle, upgrading blowoff, cooling and drying operations using engineered compressed air products is Step #3 in EXAIR’s Six Steps To Optimizing Your Compressed Air System. We’ve assigned an order to these steps in accordance with basic good engineering practice & protocol, but it’s not necessary to follow them in any particular order. In fact, all six steps really don’t apply to every single compressed air system.

Step #3 does apply to most systems, though. I spent a fair amount of time in all sorts of industrial facilities in my previous roles, servicing industrial & chemical pumps, and almost all the time, regardless of the industry or the size of the facility, the maintenance part of the facility used air guns. However, I don’t recall ever seeing an engineered nozzle on one before I came to EXAIR. Since then, I’ve worked with a BUNCH of users to dramatically reduce compressed air consumption by replacing their cheap and inefficient air guns with EXAIR Safety Air Guns, or by retrofitting EXAIR Super Air Nozzles onto their existing air guns. We actually carry adapters to fit our Super Air Nozzles to a number of readily commercially available air guns for that very purpose.

The five families of EXAIR handheld blowoff products include VariBlast Precision & Compact, Soft Grip, Heavy Duty, SuperBlast, and TurboBlast Safety Air Guns. They’re available with a range of engineered Super Air Nozzles, Extensions, and Chip Shields.

In addition to air guns & nozzles, our Air Knives have a long history of replacing drilled pipes & pipe manifolds with inefficient nozzles used to make a curtain of air flow. The following chart details the savings you can realize from the use of a 24″ Super Air Knife instead of similar devices for a 24″ wide air curtain:

Even though an electric powered blower will use less electricity than the amount of electricity an air compressor uses to supply an engineered product like the Super Air Knife, the maintenance costs make the total cost of ownership eclipse that of the engineered Air Knife.

Our Case Study Library (registration required, but it’s free & fast) documents many real-world situations where customers worked with us to gather & publish “before/after” documentation, proving out the benefits of Step #3. I encourage you to check those out, and if you think you might have an opportunity to do a Case Study with us, we offer discounts or credit for that…give me a call.

Russ Bowman, CCASS

Application Engineer
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BELIEVE

Okay, in case you haven’t been around the past year or two, and you have no clue where that simple word/statement comes from, then let me be the first to tell you that Ted Lasso is a great show, and you should check it out. So what does that have to do with EXAIR? Well, I like to think that sometimes the Application Engineers here are a lot like the coaching staff on the show. Sometimes we are strategic, we want to assert our experience and knowledge, and others, we are like Ted where we just ensure the thoughts and ideas you have already had.

That’s the fun part of being an Application Engineer here at EXAIR. I get to speak, chat, or email with both existing customers and potential new customers, resellers, and even catalog houses who all are trying to do one thing, improve a process or help someone out. Recently I was working with a manufacturing company trying to determine how fast they can cool a slab of steel with a Super Air Knife. Now, I by no means have a background in thermo like Russ Bowman, but he was busy preparing for our Spring Webinar to share some knowledge on Compressed Air System Storage. (If you haven’t checked a webinar out, most are available on our website in our knowledge base. ) So, I took the time to try and remember some of the tools I learned while at the University of Cincinnati. Thermodynamics was by far one of the hardest classes for me, The Algebra was always easy, I just always looked at the problems sideways I guess, and worried about too many variables. The truth of it is, if you keep it simple you can generally get somewhere close. so I took that approach. First I looked at what heat load would be generated by the steel slab.

\K.I.S.S. – Keep It Simple Stupid – Not always my forte!

I looked at the basic Heat Transfer equation – Q=c x m x ΔT where:

Q = Heat
c = specific heat capacity
m = mass
ΔT = Change in temperature

I was able to locate the mass of the carbon steel plate with 1/2″ thickness. So I calculated the mass of the sheet. Then looked up the specific heat of the same plate, and took the change in temperature from what the customer stated the plate started at and finished at.

This resulted in a heat load. Then to calculate how much cooling a Super Air Knife could provide I utilized another calculation that gives the BTU constant of a cubic foot of air moving and I did decrease the efficiency of the knife due to some assumptions on space and temperature constraints. The resulting factor was the customer would need 6 Super Air Knives to blow the sheet down as it travels 5 feet per minute on a 60′ long conveyor.

This again had several assumptions and I made that very clear to the customer. To convert the amount of air a Super Air Knife puts out and how much cooling it can use, I did make some clear assumptions on the temperature of their atmosphere and the amount of entrainment then I used a calculation that we adapt for Vortex Tubes and Cabinet coolers to determine what cooling load will be achieved if the air pressure or temperature is less than optimal on one of those products.

In the end, the customer received an educated estimation or calculated answer with listed assumptions, to solve their issue with cooling a steel slab before it is stacked together. I really only used two calculations and manipulated some variables to try and make sense of what I knew and what the customer needed. The best part is, this whole process is backed by our 30-day guarantee on stock products which our 48″ Super Air Knife is. So this customer can take my basic math, use my suggestions, place an order, and test it out in their facility for a factual performance test to then proceed with a permanent solution.

If you would like to discuss any point of use or potential application for compressed air in your facility, please contact an Application Engineer today!

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

EXAIR Super Air Knife Helps Bakery Protect Sheet Pan Coating

A bakery had a process where they cleaned baking sheets after they made cakes, breads, and donuts.  The system consisted of scraping the pans with brushes prior to running them through a washing system.   The excess crust material had to be removed as it could cause problems with the washing machine.  The baking sheets had a non-stick coating to help in the baking process.  The issue that they were having was that the brushes would start to remove the non-stick coating over time, causing the pans to rust.  If you needed more iron in your diet, this would not be the proper way.  The baking sheet was 18” (457mm) wide by 36” (914mm) long.  They contacted EXAIR to see if we had a better way to clean these sheets without damaging the coating. 

EXAIR has been supplying powerful non-contact ways to clean, dry, and cool products.  For this application, I recommend the model 110218SS Super Air Knife Kit.    The kit includes an 18” (457 mm) 303SS Super Air Knife, a filter, a regulator, and a shim set.  The stainless-steel construction would protect against the harsh detergents that are used in the process.  If additional protection is required, EXAIR also provides 316SS material.  The unique feature of the Super Air Knife is that it entrains ambient air at a rate of 40:1 to deliver a hard-hitting force with a small amount of compressed air.  In addition, the filter would capture any contamination from the compressed air line to keep the surface clean.  The regulator and shim set would be used to control the amount of force required to remove the debris. 

The Super Air Knife was placed just before the washing system to remove the baked contamination.  The brush system was removed.  As a bonus, they realized that they did not need to replace the brushes quarterly, which added replacement costs and maintenance time.  Sometimes these savings are overlooked.  The setup was really easy, as they only had to run compressed air to the Super Air Knife and mount anywhere from 3” (76mm) to 12” (305mm) from the sheet instead of having to periodically adjust the brushes due to the bristles shortening.

After the installation, they were amazed at the power of the Super Air Knife.  And with the non-contact cleaning, the non-stick surface was able to last much longer without having to replace the pans.  Currently, the baking sheets are lasting twice as long as they were before they started using our product.  If you have an application, where you would like to protect the surface, EXAIR has a variety of products that can create a non-contact way to clean, dry, and cool.  An Application Engineer can assist you. This customer above could now have their cake and eat it, too.

John Ball
Application Engineer


Email: johnball@exair.com
Twitter: @EXAIR_jb