Applications spotlights have become a great resource for our customers to “peak” behind the curtain. For this spotlight, let’s talk about Air Amplifiers and cellophane. Cellophane wrapping is a common mid-process way to protect products between steps in the manufacturing process. And even more often, to protect the final product.
When you unwrap the cellophane, it becomes pretty hard to dispose of, it can often be statically charged and not easily tossed in a garbage bin.
A recent customer came to us as they were removing thousands of products from their individual cellophane to bulk pack them for a big box store. This created a huge mess with mountains of trash as tall as the trash can and all over the floor.
Our suggestion was to use an Air Amplifier to carry the trash cellophane away from the unwrapping station to a trash bin with a filtered lid to trap the cellophane. We chose model 6043, 3″ Adjustable Air Amplifier. We chose this method as the Air Amplifier is designed to entrain a very large amount of air at its suction side, allowing the operator to simply get the cellophane near the suction point, and it would be pulled in with the surrounding air.
Mock up of how the station would look. The 6043 has a 3″ ID hose on the outlet that moves the blue cellophane 15 feet to a trash location. The operator in green would just have to get the plastic close and the Air Amplifier does the rest.
In addition to this application and ventilation/exhaust applications, Air Amplifiers can be used – just like our engineered Air Knives and Air Nozzles – as a useful solution for blow off, drying, cleaning, and cooling applications. If you’ve got questions about them (or any EXAIR Intelligent Compressed Air Products), give me a call.
Aluminum smelting is an important process to change alumina ore into aluminum, a lightweight metal. This process uses high heat for a period of time to separate the oxygen from the alumina. The temperature can reach over 1000oF (538oC) to cause this separation. As a reference, two pounds (0.9 Kg) of alumina ore is needed to make one pound (0.45 Kg) of aluminum. Inside the ovens and exhaust ducts, they are lined with a cement brick to contain the heat and fumes. Over time, the brick can get weak and have hot spots. Once the brick is compromised, the system has to be shut down for days to replace the brick. This is an expensive process and time-consuming. To help reduce the hot spots and extend the life of the brick, the smelting company was using ¼” copper tubes to blow compressed air to reduce the heat. This was costing the company a lot of money to operate; so, they contacted EXAIR for a better solution.
They may be inefficient, but they sure are loud…
EXAIR has been manufacturing intelligent compressed air products since 1983. And one thing that we know how to do is to save money on compressed air blow-off applications. For this company above, they had 90 open pipes throughout their plant. I was able to do a quick calculation for this customer to compare the copper tube to a Super Air Nozzle. A ¼” copper tube will use roughly 33 SCFM (935 SLPM) of compressed air at 80 PSIG (5.5 bar). As a replacement nozzle in a hot area, EXAIR recommended a model 1100SS Super Air Nozzle which will use 14 SCFM (396 SLPM) at 80 PSIG (5.5 bar). With a simple connection, they could mount the ¼” NPT Super Air Nozzle at the end of each tube. With the cost to make compressed air at $0.25/1,000 ft3, we can calculate the air savings.
Since they have 90 nozzles, this would save them $4,309.20 each week!
How can we do this? With cooling capacities, it is dependent on the mass of air that can be moved. With our Super Air Nozzles, we are near an amplification ratio of 25:1. This means that for every one part of compressed air, we can entrain 25 parts of ambient air. Also, with our Super Air Nozzles, we can generate a laminar air flow which has a velocity profile that has the air moving in the same direction. An open pipe has turbulent flow, which means that the velocity is traveling in different directions and not working together. And the amplification ratio is very low. I did a demonstration to illustrate this effect here: Video Blog: Laminar and Turbulent Flows. The large volume of air creates good cooling without using too much compressed air to reduce the hot spot temperatures. In keeping the temperature under control, they could continue operations and lessen the concern for untimely shut-downs and costly maintenance.
By using air to cool, you can do it safely and efficiently. As a benefit, the Super Air Nozzles reduced the noise level as well. Saving a lot of money; having an effective way to reduce stress on the cement bricks; and reducing the noise nuisance were great replacements for this company. If you would like to speak about cooling applications, you can contact an Application Engineer; even something as large as a smelting oven.
Quick adjustment by turning the exhaust end into or out of the body to infinitely set compressed air flow and hence, performance.
Super Air Amplifiers (left) can be easily installed using the 2-bolt mounting flange. Adjustable Air Amplifiers are compact & light enough to be supported by supply piping, even using a Swivel Fitting if you like.
Strictly considering air flow performance, there aren’t really any applications where one design will work, and the other won’t. Once the right size is determined, selection comes down to material of construction, how it’ll be installed, where it’ll be installed, and whether it’ll need to be quickly adjusted for flow & force on the device, instead of by regulating the compressed air supply.
I had the pleasure of talking to a caller just this morning about a “textbook” application for an Air Amplifier: welding smoke ventilation.
Maybe instead of a “textbook”, I should call it a “catalog” application because it’s literally the first image you see when you get to the Air Amplifiers section of the EXAIR Catalog.
Another important consideration for the caller was maximizing the exhaust flow. Looking at the performance data for the 4″ Super Air Amplifier and the 3″ Adjustable Air Amplifier, the latter generates just a little higher total air volume at the outlet, which, when you subtract the compressed air consumption from it, gives you the total flow rate of entrained air (and welding smoke, in this case):
The 730 SCFM Air Volume at Outlet, minus the air consumption of 29.2 SCFM, means that it’s drawing in ~700 SCFM. Which is not bad.
The 774 SCFM Air Volume at Outlet, minus the air consumption of 29.2 SCFM, means that it’s drawing in ~740 SCFM. Which is even better.
In addition to ventilation/exhaust applications, Air Amplifiers can be used – just like our engineered Air Knives and Air Nozzles – in blow off, drying, cleaning, and cooling applications. If you’ve got questions about them (or any EXAIR Intelligent Compressed Air Products), give me a call.
Russ Bowman, CCASS
Application Engineer Visit us on the Web Follow me on Twitter Like us on Facebook
1. Efficiency – With an air entrainment ratio of 40:1 (literally means it pulls in 40 SCFM of “free” air from the surrounding environment for every 1 SCFM of consumption), compressed air consumption is dramatically lower than any other blow off device.
EXAIR Intelligent Compressed Air Products such as (left to right) the Air Wipe, Super Air Knife, Super Air Nozzle, and Air Amplifier are engineered to entrain enormous amounts of air from the surrounding environment.
2. Laminar air flow – My colleague John Ball did a bang-up job in a video blog explaining the fluid mechanics theory behind this. Operationally, laminar flow is is beneficial because it’s particularly conducive to generating a stripping or sweeping action, as opposed to the turbulent flow from an open blow off, a blower, or a fan.
3. Quiet operation – The high entrainment ratio that makes the Super Air Knife so efficient also makes for amazingly low sound levels. The outermost entrained air creates a boundary layer that attenuates the sound level of the higher velocity, hard hitting center flow.
4. Lengths available – Super Air Knives are stocked in lengths from 3″ to 9ft. Custom lengths can be made if you’re space-limited for installation, and custom shims can be installed if you want to shorten the curtain width of a stock Super Air Knife. Super Air Knives can also be coupled together for even longer lengths.
Air Knife Coupling Bracket Kits are available from stock for Aluminum, 303SS, and 316SS Super Air Knives.
5. Material of construction – No matter how aggressive the environment is, odds are, EXAIR has a Super Air Knife that’ll hold up to it. Durable aluminum models are good to 180°F (82°C). There are also two Types of Stainless Steel to choose from: 303SS for high strength, and 316SS for protection from chloride pitting corrosion & higher strength. Both 303SS & 316SS are good to 800°F (427°C). For exceptionally harsh environments, PVDF (Polyvinylidene Fluoride) constructed Super Air Knives have Hastelloy C-276 hardware & PTFE shims, which are resistant to UV light, inorganic chemicals, solvents, ozone, weather, fungi, chlorinated hydrocarbons, highly corrosive acids, weak bases, and salts. They’re good to 275°F (135°C).
6. Easy installation – Like all of our products, the Super Air Knives – from the 3″ to the 9ft models – are “user friendly” as far as mounting & installation goes. The Model 9060 Universal Air Knife Mounting System makes for quick installation and easy positioning. 24″ to 42″ Super Air Knives need to be plumbed to both ends…if you hard pipe the air supply, the Super Air Knife itself will essentially be as well supported as the piping. The same holds true for longer Super Air Knives with Plumbing Kits installed. 3″ Super Air Knives can even be fitted with Stay Set Hoses, and Magnetic Bases. And the 1/4″-20 tapped holes on the bottom of the body allow for a wide range of mounting solutions…anything you can put a bolt through, really.
Yes, that’s a door hinge. No, it wasn’t my idea ( but I kind of wish it was.)
7. Low maintenance – With no moving parts, they’ll run darn near indefinitely, maintenance free, as long as you supply them with clean, moisture free compressed air. Oh, and keep them clean, externally, if they’re in an area where environmental contaminants can build up on the precision finished surfaces that are essential to their air entrainment.
8. Reliability – Hand in hand with #7, no moving parts also means there’s not much that can stop them from working. They can operate continuously, if needed, or you can cycle them on & off as frequently as necessary to keep from using valuable compressed air, except when needed.
EXAIR’s award winning EFC Electronic Flow Control can be set to operate a Super Air Knife (or any of our Intelligent Compressed Air Products) in cycles as low as 0.1 seconds.
9. Static Eliminator option -The laminar, high velocity air flow is ideal for many blow off applications, but if static charge is a problem, an Ionizing Bar can be installed, turning the Super Air Knife into a Super Ion Air Knife:
10. Free stuff – OK; this last one is “super” for a limited time. Order a Super Air Knife between 11/1/22 and 12/31/2022, and get a FREE Safety Air Gun. Click here for details.
If you’d like to find out how the Super Air Knife – or any of our Intelligent Compressed Air Products can help you get the most out of your compressed air system, give me a call.
Russ Bowman, CCASS
Application Engineer EXAIR Corporation Visit us on the Web Follow me on Twitter Like us on Facebook
