Super Air Knife Makes EVERYTHING Better

When we compare the EXAIR Super Air Knife to other methods of providing a curtain or sheet of air flow in terms of operating cost, efficiency, safety, and sound levels, the Super Air Knife is ALWAYS the clear choice.

The EXAIR Super Air Knife is the most efficient and quietest compressed air blow off product on the market today.

The Super Air Knives successfully replace these, and many other methods of providing a curtain or sheet of air flow all the time, while saving compressed air and decreasing noise.  The word “replace” oftentimes means “do the same job as.”

What you’re about to read is NOT one of those times.

A paper products manufacturer has a machine that treats a specialty product, and the process generates ozone (O3) at levels that would exceed personnel exposure limits, so they need to be contained.  They installed a long piece of drilled pipe to blow an air barrier, but they could only run the machine at about 65% of their desired capacity before the ozone level in the operators’ area exceeded their limits.

This company was familiar with several of our product lines already…they had several Cabinet Cooler Systems, a Reversible Drum Vac, and Super Air Knives in a variety of applications, so they knew how they worked.  Since the barrier needed to be 120″ long, though, this was going to be a much larger scale than they were used to.

Not only was the drilled pipe loud and inefficient, it was not particularly effective either.

Still, the installation of two Model 110060 60″ Aluminum Super Air Knives, coupled with our Model 110900 Air Knife Coupling Kit, was quick and easy.  Then came the good part: they found they were able to operate the machine at 100% capacity, while keeping the ozone at a safe level in the operators’ area.

EXAIR Super Air Knives provided a total solution: quiet, efficient, and most of all, EFFECTIVE.

Then came the better part:  The machine was pretty loud (we couldn’t do anything about that,) at 93dBA when it was running.  With the drilled pipe in operation, it was 94.5dBA.  When they took that out and installed the Super Air Knives, there was no net increase in noise level…it remained at 93dBA.

THEN came the even better part: Compressed air consumption was reduced to about 30% of what the drilled pipe was using.  Right in line with our table above.  Just another validation of the trustworthiness of our published data.  As EXAIR’s President is fond of saying, “Claims are easy, proof is hard.”

If you’re looking for a quiet, efficient – and effective – solution for a compressed air product application, give me a call.

Russ Bowman
Application Engineer
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Versatile, Efficient And Quiet: The EXAIR Super Air Knife

It would be a memorable day in Application Engineering if one of us didn’t handle at least one call regarding a Super Air Knife. They’re just used for so many different purposes: from debris blow off, to drying, to cooling – in fact, a good number of “Super Air Knife calls” start as “Vortex Tube calls,” because both have their place, depending on factors such as how hot the part to be cooled is, what temperature you want to get it to, how fast does it need cooled, etc. More on that here, and here…today, I’m going to write about environmental containment and separation.

In a nutshell, that means keeping smoke, fumes, powder, etc., inside an area, or at the very least, away from another area. A couple of examples of this are documented in the Super Air Knives section of our latest catalog. If you don’t have one, click here.

The first features:

lens clearing
(2) Model 110024 24″ Aluminum Super Air Knives, which keep the smoke from machining oil that burns off during an engine test directed into the vent hood.

The second utilizes:

A Model 110006 6" Aluminum Super Air Knife to keep the slag, spatter, and smoke from a laser cutter away from the lens of the machine's visual inspection system.
A Model 110006 6″ Aluminum Super Air Knife to keep the slag, spatter, and smoke from a laser cutter away from the lens of the machine’s visual inspection system.

A third, which I don’t have pictures of yet because it’s brand-new, is a little larger scale: a recent caller was looking for a way to keep ALL the powder inside his powder coating spray booth. There’s an open vent with runs all the way across the top, and, when the booth is in operation, a very small plume exits along its 90″ width. They purchased a Model 110296 96″ Aluminum Super Air Knife Kit to blow a continuous curtain of air across this 4″ wide gap, angled down slightly into the booth. The Kit’s Pressure Regulator allows them to “dial down” the air flow to a level just high enough to keep the powder from exiting the gap, but also low enough to not disturb the powder coating process inside the booth.

A self contained blower unit was actually their first idea…these are very popular for large doorways…you’ve probably even seen them on large doors on shipping docks, or forklift paths inside plants where it’s necessary to keep pollutants from one room from entering another. For this situation, though, the compact size, low sound level, and precise adjustability of the Super Air Knife’s air flow made it the logical choice.

If you’d like to know more about EXAIR Super Air Knives, or any of our Intelligent Compressed Air Products, give me a call.

Russ Bowman
Application Engineer
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What Size Pipe Should I Use?

Yesterday, I had a customer with a tough application for a Standard Air Knife. The customer was quenching individual 11″ x 11″ steel plates in oil after they had been heated to over 1,200° Celsius. Following quenching, the plate is pulled out of the oil with a fair amount of excess oil still attached. This excess oil is relatively hot and could be dangerous, if it drips from the plates as they are conveyed to the next process. The oil removed from the tank is also lost, so the tank needed to be refilled regularly. This oil added up to quite a large expense every year for this company. The customer installed (2) 12″ Standard Air Knives above the oil quenching tank to blow the oil off of the plate back into the oil quenching tank as the plate is raised out of the tank and in between the two air knives.

How the Standard Air Knife Works
How the Standard Air Knife Works

The customer called to express some disappointment about the air knife performance, I asked him a few questions about his application.

Q:What pressure is supplied to the air knife?
A: 100 PSI
Q: Where are you measuring this pressure?
A: That is our shop pressure and the pressure I’m measuring at the regulator.
Q: How are you connecting the regulator to the air knife?
A: We are using 10 feet of 3/8″ ID tubing.

At this point I suspected that the problem was in the compressed air supply line. To confirm this, I asked the customer to install a pressure gauge in the unused air inlet of the air knife. This pressure gauge read only 52 PSIG. The customer had a pressure drop of 48 PSI through the 10 foot of 3/8″ tubing, fittings, and valves that connected the regulator to the air knife.  The 12 inch Standard Air Knife utilizes 41 SCFM of compressed air when fed with 80 PSIG. In order to determine what to expect for a reasonable pressure drop, you could use EXAIR’s Air Data charts. According to EXAIR’s air data chart, for 1/8″ schedule 40 iron pipe, which has around 1/4″ ID (Which is very similar to the Inside Diameter of the 3/8″ tube) at 8 SCFM of flow the line will create a 18.6 PSIG pressure drop. When you try and shove more than 8 SCFM through the 3/8″ OD (1/4″ ID) tubing, you create a higher pressure drop. In this customer’s case it created a 48 PSI drop across the air line. This 48 PSI pressure drop was caused by the supply line as well as the fittings or valves used to connect valve to the regulator. This pressure drop limited the air knife to only 52% of its performance. In an application with a viscous fluid like oil , this drop in pressure led to lower force upon the steel plate and disappointing performance.

After getting the proper plumbing in place, the pressure drop was eliminated and the the Air Knives were operating at peak performance to remove the oil from the plates.

During the course of our troubleshooting, the customer also discovered Russ Bowman’s excellent video Proper Supply Plumbing for Compressed Air Products. In the video, our customer discovered the impact both the cross sectional area and overall length of compressed air piping can have on the performance of an air operated device.

The customer wanted to use a 12″ Air Knife to blow off the oil from the plates, which is a great application for the air knife. By properly plumbing the supply of an Air Knife, the customer contained hot oil, reclaimed quenching oil for future use, and maintained a clean shop floor. This installation was well worth the time and effort of installing the air knife properly. If the customer would like, we also have a Super Air Knife which will only use 35 SCFM and could help to save more compressed air. This savings of 7 SCFM may not seem like much, but it will have a significant impact on the energy cost of running his air compressor.

Dave Woerner
Application Engineer
@EXAIR_DW
DaveWoerner@EXAIR.com

Engineered Solutions Are Cost Effective

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One of the easiest ways to solve a blow off application is to install an open pipe or tube; it’s generally quick and available. They are easy to make, mainly you just need some pipe, maybe a hacksaw and hammer, and a way to hook them up to your compressed air system.  They will provide a good amount of force but at the cost of safety, noise level, and air consumption. That’s right: it will cost you in SAFETY, NOISE EXPOSURE and COMPRESSED AIR CONSUMPTION. I’m going to go out on a limb here (not really) and wager there are a number of folks in any organization unwilling to pay those costs – if you are willing, you may want to reconsider.

I have been to many manufacturing facilities where they have used copper line to bend into a tight space and then pump 85 psi into the pipe in order to try and blow a piece of lint out of a roller or to keep trim from getting caught in a pulley system.  In some cases I have seen 3/8″ ID pipe to keep dust and lint out of a pulley.

This is not needed at all.   The estimated flow through a 3/8″ ID tube that is around 3′ long would be roughly 109 SCFM when powered at 85 psig.   All to keep dust off and loose fiber out of a certain area.  The reason they plumbed this large of a piece of tubing into the area was simple, it’s what they had and it worked great (words from the maintenance worker). For additional reference, our 91 SCFM air nozzle produces 4.5 pounds of force which seems a bit of overkill when you can blow dust away with your breath.

20140903_164126

In one instance I looked over the material and scrap they were trying to keep from getting to the outer workings of the machine I made the recommendation for them to utilize a model 1100SSW, –  a 1/4 NPT Stainless Steel Super Air Nozzle w/ Swivel Fitting.   This would give them flexibility to target the right area through the swivel and require them to change the existing tubing out to a schedule 40 threaded pipe, or use a compression style fitting.

By replacing the single nozzle, the customer was able to reduce compressed air consumption in just this single blow off point from 109 SCFM at 85 psig to 14 SCFM at 80 psig inlet pressure.  This single replacement equates to saving 95 SCFM, or $11.40 per 8 hour shift that the blowoff is operated.   If the customer operated this blowoff 24 hours a day it would take a mere 4 days to pay the unit back in air savings.

The above savings do not include the benefit of being able to reduce the overall operating pressure of the compressed air system feeding this application to 80 psig, instead of 85 psig. In case you weren’t aware, if you lower the pressure value where your compressor shuts off, say from 85 psig to 80 psig, it will save an estimated 2.5% of drive energy for their air compressor.   Depending on the type and size of the compressor this could amount to a substantial savings.  This system pressure reduction will also lower the operating pressure of any leaks that may be within the system which will also be another amount of savings.  All of this is from simply replacing open pipe with an engineered nozzle.

This was just one area where the quick and easy way turned out to be the costly and dangerous path.  The best part about our engineered solution is they are all in stock, ready to ship same day.  This means you can find the problem today, have a solution waiting to be installed tomorrow.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

Outside Your Comfort Zone?

Over the past several months I have found myself more and more outside of my comfort zone throughout the day.  This feeling has been declining over the past few months, however, as the situations which cause discomfort seem to come up more and more every day so my comfort zone is constantly expanding. I like comfort zones, but also understand that being outside of them helps me to learn and gain new experience. I bring this up because I had a customer come in yesterday so they could be shown a demonstration of an EXAIR Super Air Knife.

Now, customers coming in is not a problem at all, I spoke with him last week and we discussed the application.  This time, it was outside of his comfort zone so he wanted to come in.  Well, when I got the call I had a visitor I grabbed a single business card and walk out to find that there were four gentlemen waiting to see me, not just one.  Still, not a problem. I showed them to our fully stocked demo room and we proceeded to discuss their application.  They were hoping to make the environment their employees work in a little cleaner.  They had new down draft work benches which had three sides on it.

The problem the team was having is that all their operators were using hand-held grinders to deburr parts as they were manufactured.   The downdraft table was added to help prevent the dust and debris from getting all over the operators, however it wasn’t working good enough.  So they started looking and found EXAIR Super Air Knives.  They didn’t believe that a Super Air Knife would move enough air and still be quiet enough to have an operator sitting at the station, so they drove down to our facility and I showed them all the benefits that a Super Air Knife has.  This was all based off a 6″ Aluminum Super Air Knife I had handy.  I then swapped the stock .002″ thick shim out with a .001″ thick shim.  They were amazed at how quiet the Super Air Knife was (with either shim) and how the flow of air was enough to disturb and direct dust but not over powering and blowing parts off the table. LSAN I could definitely see that they were impressed by the simplicity of working with the Super Air Knife and the performance it achieved. But alas, they were still trying to figure out how a 48″ would work, so I went straight out and got a 110048 off the shelf and hooked it up for them.  That was all that they needed in order to really get the wheels in their heads spinning into overdrive.   They all left with my contact information and catalogs in tow but I didn’t hear them stop talking about the possibilities until they were in the car.

The fact of the matter is that they were outside of their comfort zone and had no concept of how you could make compressed air blow in a laminar sheet to help contain dust in a down draft work bench.  Once they saw how easy the Super Air Knife was to hook up and mount they were instantly back into their comfort zone of making their employees happy and safe. If you have some applications using compressed air and you are well out of your zone, contact us.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

You Make A Better Door Than A Window

As a life-long smart aleck, this phrase has always been one of my favorite ways to gently request that someone move to one side or the other so that I can see what they’re looking at. As I’ve mellowed with age, it’s largely replaced the more demanding “Yo, down in front!!” which I’ve learned to save for only the most urgent of situations. These usually occur at sporting events, where, unfortunately, it’s some of the more tame language you’ll hear at stadiums and ballparks these days.

In industry, there are certainly proper places for doors: Nothing beats a solid-core, well-sealed door to keep welding smoke out of the office space at a manufacturing company. On a smaller scale, sand blast cabinet manufacturers realize that their cabinets’ doors are so important, they put switches on them to prevent you from starting one up with the door open.

But what if it’s not practical – or possible – to put a solid boundary between a contained area and the general environment? EXAIR Super Air Knives are successfully used in “air barrier” applications in industries as diverse as metal processing, pharmaceuticals, high detail printing, and commercial laundry equipment.

Air Knives aren’t the only EXAIR product with documented success in this area: In addition to cleaning the rod, this Super Air Wipe, installed flush with the wall of the enclosure, also keeps the oil & mist contained inside the processing machinery:

AirWipe

Our Line Vac even got a piece of the action with a commercial maker of baked goods: A part of their process involves mixing sugar into a vat of melted butter. The heat and steam tended to melt the sugar, though, before it made it all the way down the chute into the vat. This not only wasted a good deal of the sugar, but made for a real hassle in cleaning the chute. They installed a Model 6066 3” Stainless Steel Line Vac in the chute, which not only kept the sugar moving fast enough to prevent it from melting, but it also kept the heat & steam from “migrating” up the chute.

If you have an air barrier application you’d like to discuss – or any compressed air application, for that matter – we’d like to hear from you!

Russ Bowman
Application Engineer
EXAIR Corporation
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