EXAIR GEN 4 Super Ion Air Knives remove static electricity from plastics, webs, sheet stock and other product surfaces where tearing, jamming, debris or hazardous shocks are a problem. The laminar sheet of air sweeps surfaces clean of static, particulate, dust and dirt. Production speed, product quality and surface cleanliness can improve dramatically.
The GEN 4 Super Ion Air Knife floods an area or surface with static eliminating ions – up to 20 feet (6.1 m) away. A uniform airflow across its length will not cause misalignments to critical surfaces such as webs. Force can be adjusted from a “blast” to a “breeze”. The GEN 4 Super Ion Air Knife is electrically powered, shockless and has no moving parts. It also only requires 3.7 SCFM of compressed air per foot of length at 5 PSIG (105 SLPM per 300mm of length at 0.3 BAR). The sound level is also surprisingly quiet at 50dBA for most applications.
Compressed air flows through an inlet (1) into the plenum chamber of the GEN 4 Super Ion Air Knife. The flow is directed to a precise, slotted orifice. The primary air flow exits, it creates a uniform sheet of air across the entire length that immediately pulls in surrounding room air (2). An electrically powered GEN 4 Ionizing Bar (3) fills the curtain of air with positive and negative charge. The airstream delivers these static eliminating ions to the product surface (4) where it instantly neutralizes static and cleans dust and other particulates.
EXAIR’s GEN 4 Super Ion Air Knives offer a convenient, safe and reliable method for eliminating static charge while improving efficiency and quality. If you have questions or need help selecting the right product for your application please contact on of our Application Engineers.
Vortex Tubes are near the top of the list of the most interesting uses of compressed air: Cold (and hot) air, generated instantly, from a device with no moving parts. Why don’t we use them for EVERYTHING? It’s not that it CAN’T be done, but it can be impractical to do so. Consider:
While researching our Cabinet Cooler Systems, some callers will ask about using this technology to cool a space larger than an electrical panel, like a server room. I spoke with just such a caller once, who had 7.5kW worth of heat estimated in a server room that was under construction, and had been asked to research cooling solutions…so we did:
Since 1 watt equals 3.41 Btu/hr, 7.5 kilowatts equals 25,575 Btu/hr worth of cooling required.
Our highest capacity single Cabinet Cooler generates a cooling capacity of 2,800 Btu/hr, so we talked about ten of them, for ~10% safety factor, which was reasonable for the purposes of our discussion.
Each 2,800 Btu/hr Cabinet Cooler uses 40 SCFM @100psig, for a total of 28,000 SCFM. Using a common thumbrule that says a typical industrial air compressor generates 4 SCFM per horsepower, that means they’d need a 100HP compressor (or that much capacity from their whole system) just to run these Cabinet Coolers. Adding that cooling capacity to their HVAC requirements made more sense.
Of course, with every rule, there’s an exception: an independent crane operator carries a Model 3250 Large Vortex Tubewith him for cab cooling in the tower cranes he’s contracted to operate. While the US Department of Energy considers “personnel cooling” to be an inappropriate use of compressed air, the small fans typically found in these cranes’ cabs offer little comfort to an operator spending all day, 50 feet off the ground, in the summer heat of the Deep South!
Another common question regards the use of a Vortex Tube with another EXAIR product…the most common being an Air Knife. These callers want to blow cold air onto something, but instead of the conical and relatively small flow pattern the Vortex Tube discharges, they want to blow a curtain of cold air. The design & function of both the Vortex Tube, and the Air Knife, work against this idea:
The cold air has to exit the Vortex Tube at, or very near, atmospheric pressure. If it encounters much back pressure at all, performance (as measured by the temperature and flow rate of the cold air) will deteriorate.
An Air Knife, by design, is pressurized all the way to the point where the compressed air flow exits the 0.002″ thick gap. That’s far too much back pressure for a Vortex Tube to operate under.
Even if the Vortex Tube DID supply cold air, under pressure, to the Air Knife, the tremendous amount of environmental air entrained by the Air Knife would still result in a total developed flow temperature that was much closer to ambient temperature for the area.
One “workaround” for this is what we informally call a “cold air knife” – that’s when you plumb the cold air from a Vortex Tube into a length of pipe with a series of holes drilled along its length. Let’s say a building products manufacturer wanted to blow cold air across a 10ft wide continuous sheet of roofing material…because they did:
I recommended that they take a PVC (because it’s non-conductive and wouldn’t transfer heat from ambient as fast) pipe a little longer than 10ft, cap the ends, drill 1/8″ holes every inch (total of 120 holes).
From the table below, we see that a 1/8″ diameter hole can flow as much as 1.1 cubic feet per minute @1psig*, so 120 of those holes will pass ~132 cubic feet per minute worth of air flow.
Four Model 3240 Vortex Tubes were specified: when set to an 80% Cold Fraction, 80% of the 40 SCFM that each will consume, or 32 SCFM, is directed to the cold end. 32 SCFM X 4 3240’s = 128 SCFM. Close enough. They plumbed those 4 Vortex Tubes at approximate equal distances along the length.
AModel 3215 Medium Vortex Tube supplied @100psig will flow 10 SCFM worth of cold air when set to a 67% Cold Fraction**, which will give us a curtain of cold air that’s a little more than 71°F colder than the compressed air supply:
If you’ve got an application involving the need for cold air, on demand, EXAIR has a variety of products that’ll do just that. Give me a call to find out more.
Russ Bowman, CCASS
Application Engineer EXAIR Corporation Visit us on the Web Follow me on Twitter Like us on Facebook
I’ve blogged before about having a fantastic wife and three smart and rapidly growing daughters. Our nightly routine is one that gets to be cumbersome and sometimes painful, at the same time, I wouldn’t change a single aspect as it gives both my wife and me one on one time with each girl. Even my pre-teen daughter still wants this one-on-one time when we just sit and calm down from the day by talking or singing in her case. I know it won’t last forever, so I always try to stay present. Here lately all three of my daughters on different days have asked me what I do at work during the day. It caught me off guard all three times.
They know that I work for EXAIR, and they know we make “stuff”, they’ve been to the company parties and even had lunch with me here in the office, they still didn’t know what I did, and at the time each one asked, even I didn’t know what I did. The answers I gave were all fairly similar. I help people figure out how to fix stuff by using the stuff we make. If they have something from EXAIR that isn’t working then I help them figure out why it isn’t working, and we try to get it fixed. Then they would ask things like, if their car is broken they call you, no that’s only when I’m at home. I tell them I also get to test products and see what they can do, even make videos of what our stuff does. Of course, they wanted to know if I made TikToks and I proudly informed them I do not and that most of this stuff is on a website or on YouTube.
The fact is that they know I love to work with my hands and see my work around the house or at other people’s homes on their cars or on their projects. They know that I value my experiences and I always try to have them recall an experience they may have already had when they are struggling with something. The best is when my oldest is learning about heat transfer. First, we did an experiment with my trusty Zippo lighter, so she experienced that holding your hand six inches over a flame you can feel the warmth but underneath you can’t. Then I showed them Vortex Tube Videos. They didn’t find it as cool as I do. (DAD PUN INTENDED!)
Lucky for me, when people are contacting me at work, they generally get excited about seeing compressed air turned into hot and cold air streams without moving parts and being able to solve heat transfer issues quickly and easily. The exact opposite reaction of young children, which helps me not feel like such a nerd.
The point of this story is that I am here to help, it’s one of the key responsibilities I hold as an Application Engineer here at EXAIR. With that, I share all of my experience that comes with over 15 years in the industry and always keep my eyes and ears open when I don’t know something. If you are at a wall with your point-of-use compressed air system or a process in your manufacturing, contact us and see how our bank of experience can help you to determine the best path moving forward.
Medically speaking, our skin is an organ…and an amazing one at that. It protects our internals from an incredibly harsh environment as we’re bombarded by radiation (sunlight), subjected to summer’s heat & the cold of winter, attacked by fierce invaders (from viruses & bacteria to insects & spiders), all while we carry on at the bottom of a 60 mile-deep ocean (of air!)
Our skin requires some protection too: Sunscreen mitigates some of the harmful effects of solar radiation, shoes protect our feet from the ground, gloves & coats prevent frostbite, and compliance with OSHA Standard 1910.242(b) protects operators who use compressed air devices for cleaning purposes from air embolisms. That’s when air, under pressure, has enough energy to break the skin (tough as it is) and reach the tissue underneath. It’s painful, and serious enough that the victim should absolutely seek emergency medical treatment. If the air breaks a blood vessel and enters the pulmonary system, it can be deadly, in a hurry.
In 1971, the U.S. Occupational Health and Safety Administration (OSHA) determined that air under pressure higher than 30 pounds per square inch is capable of causing such injuries, if the pressurized source is dead-ended into the skin. Based on this determination, they included the following verbiage in Standard 1910.242, regulating the safe operation of hand and portable powered tools & equipment:
1910.242(b)Compressed air used for cleaning. Compressed air shall not be used for cleaning purposes except where reduced to less than 30 p.s.i. and then only with effective chip guarding and personal protective equipment.
In February 1972, OSHA issued Instruction STD 01-13-001 to clarify the meaning of 1910.242(b), with two illustrations of acceptable methods to meet compliance. The first is the use of a pressure reducer (or regulator):
The other method illustrated in the Instruction’s enclosures involves the nozzles themselves:
One design that complies with OSHA 1910.242(b) using this method is the cross drilled nozzle:
If you’re not concerned about high operating cost or deafening noise, you can stop reading now; these are all you need for OSHA compliance with Standard 1910.242(b). If you DO care about spending less money on compressed air or complying with OSHA Standard 1910.95(a) (which you read all about here), let’s spend a minute on engineered compressed air nozzles:
In addition to making them cost less to operate (since most of the total developed air flow is entrained), they’re also VERY quiet (since the entrained air forms a boundary layer on the outside of the air stream), AND they can’t be dead ended:
All EXAIR Intelligent Compressed Air Products, in fact, incorporate a form of built-in “relief device”:
If you’d like to discuss safe use of compressed air, it’s one of our primary goals here at EXAIR – give me a call.
Russ Bowman, CCASS
Application Engineer EXAIR LLC Visit us on the Web Follow me on Twitter Like us on Facebook