Vortex Tubes – The Basics, And Beyond

The Vortex Tube might be just about the most interesting compressed air device around.  They have no moving parts, and they don’t need any but a compressed air supply, which they ‘split’ into a hot air stream, and a cold air stream.

EXAIR Vortex Tubes come in three sizes – Small, Medium, and Large – and 24 distinct Models across those three sizes.  They’re all in stock, along with Hot & Cold Mufflers (for sound level reduction,) Automatic Drain Filter Separators (to keep the air supply clean & moisture free,) Oil Removal Filters (to coalesce any trace of oil from the air supply,) and Solenoid Valves & Thermostats (to automate operation.)

From left to right; a few value added accessories for your Vortex Tube: Hot Muffler, Cold Muffler, Automatic Drain Filter Separator, Oil Removal Filter, and Solenoid Valve/Thermostat Kit.

The Vortex Tube, right out of the box, is easily adaptable to a wide range of cooling (or heating) applications.  If your needs are specific, though, we can customize a Vortex Tube to meet them:

  • Material of construction: our stock Vortex Tubes are made of 303SS and are equipped with a plastic Generator and Buna o-ring.
    • For high temperature (>125F ambient) applications, we can install a brass Generator and Viton o-ring, suitable for ambient temperatures up to 200F.
    • If the environment is particularly aggressive, or if industry codes (I’m looking at you, food & pharma) call for it, we can also make them out of other materials.  We’ve, for instance, made them out of 316SS, complete with material certifications, when needed.
  • Flow & temperature: the Hot Valve can be opened or closed to dial in a particular Cold Fraction (that’s the percentage of the supply air which is directed to the cold end.)  If you know what flow rate and temperature you want, we can replace the Hot Valve with a non-adjustable plug, so your Vortex Tube’s cold flow is only dependent on the compressed air supply temperature and pressure.
  • Accessories: if you’re looking for features like a magnetic base, or a flexible cold air hose, you might consider an Adjustable Spot Cooler.  If you like the idea of tool-free change of air flow/temperature, that’s definitely the way to go.  If you want those other options, and don’t mind using a screwdriver to adjust the Cold Fraction, those other options are compatible with any Medium Vortex Tube.
Model 3925 Adjustable Spot Cooler

These are just a few of the most common possibilities for customizing a Vortex Tube.  If you have a spot cooling application you’d like to discuss, give me a call.

Russ Bowman
Application Engineer
EXAIR Corporation
Visit us on the Web
Follow me on Twitter
Like us on Facebook

Compressed Air Supply Side: What Is A Deliquescent Dryer, And When Would You Use One?

As we head in to the colder months here in Ohio, I will soon be getting my humidifier out of the basement and set up in my bedroom. The dry air that accompanies the onset of winter chaps my lips, cracks the skin on my knuckles, affects my nasal passages, and oftentimes makes me wake up with a sore throat…something I definitely don’t want to happen in the middle of a pandemic! So I put some water vapor in my home’s air, on purpose, to take care of all of that.

Moisture in an industrial compressed air system, however, isn’t good for anything.  It’ll corrode your pipes, get rust in your pneumatic tools, motors, and cylinders, and spit out of your blow off devices, all over whatever you’re using your air to blow off.  Depending on the type of compressor, where, and how, it’s used, there are different types of dryers.  Today, dear reader, we’re taking a look at one of the most basic moisture removal systems: the deliquescent dryer.  The principle of operation is as follows:

  • Deliquescent dryer: how it works (1)
    Incoming compressed air enters near the base, where a form of mechanical separation occurs…the air flows back & forth, around trays of desiccant.  The simple act of changing direction causes a certain amount of free liquid to just fall out and collect in the bottom.
  • The air then flows upwards through the desiccant bed. The desiccant in a deliquescent dryer absorbs moisture (as opposed to the adsorption that occurs in a regenerative desiccant dryer) until they get so wet, they dissolve.
  • The desiccant level has to be monitored (commonly via a sight glass) so it can be replaced as it’s consumed.
  • After the desiccant does its job, moisture free air flows out the top, and gets on with it’s work.

Deliquescent dryers, owing to their simplicity, are the least expensive air dryers.  They have no moving parts and no electricity, so the only maintenance involved is replacing the desiccant media as it’s consumed.  This makes them especially popular in mobile/on-site applications involving portable or tow-behind, engine driven compressors, since they don’t need power to run.

There are several disadvantages, also owing to their simplicity:

  • The deliquescent media has to be periodically replenished.  If you don’t stay on top of it, you can find yourself shut down while you go back to the shop to get a big bag of salt.  That’s time your boss can’t charge your customer for.  Also, the cost of the new media is a continual operating cost of the dryer…something you don’t have to account for with the regenerative desiccant models.
  • Disposal of the waste media can be a concern…you definitely want to check your local environmental regulations before dumping it in the garbage.  Your boss won’t like talking to the EPA about THAT either.
  • They have to be equipped with a particulate filter on the discharge to keep the deliquescent media (which, being a salt, is corrosive in nature) from entering your system.  That would be even worse than water moisture…which this is there to prevent in the first place.
  • They don’t get near as low of a dewpoint as other dryers – the best you can hope for is 20°F to 30°F.  Which is fine, given the above mentioned nature of applications where these are commonly used.  You just wouldn’t want to use them to supply a product like an EXAIR Vortex Tube…which can turn that in to -40°F cold air, causing the water vapor to turn to liquid, and then to ice.  In a hurry.

EXAIR Corporation is in the business of helping you get the most out of your compressed air.  If you want to learn more, please follow our blog.  If you have specific questions, give me a call.

Russ Bowman
Application Engineer
EXAIR Corporation
Visit us on the Web
Follow me on Twitter
Like us on Facebook

 

(1) – Deliquescent Dryer Image: VMAC Air Innovated: The Deliquescent Dryer – https://www.vmacair.com/blog/the-deliquescent-dryer/

Tried and True Products with Modern Performance and Safety Features

Over Labor Day I got the chance to take my dad and his friend climbing in Seneca Rocks West Virginia for the first time in a very long time. Seneca Rocks is a large Quartzite knife edge located in the Monongahela National forest on route 33. The majority of climbing there is what is known as Trad Climbing, which is just short for traditional climbing and is where one must place their own protection to clip the rope into (also pray it holds when you fall). Trad climbing requires a strong mental fortitude and precise physical movements as you jam different parts of your body into various sized cracks.

Me on the left and my Dad’s friend at the trail head for the hike to “the walls”.

In the ever-expanding world of new technology and advancements of outdoor adventure gear, all trad climbers stick with the same gear that was used some 30+ years ago. Although the materials and performance have improved the very principle and mechanics behind them has not. In this case the old saying “If it ain’t broke don’t fix it!” rings true. Sometimes when it comes to a solution, whether its hanging 200’ in the air or updating a process line, traditional is a great choice due to its simplicity and effectiveness.

Compressed air has been around since 1799 but the idea has been around since 3rd Century B.C. making it one of the oldest utilities next to running water. When it comes to manufacturing applications it’s about as tried and true as you can get, so why not look into our engineered products to help you solve your issues. Their simplicity and effectiveness remain, while their efficiency, safety and performance have been engineered to modern day needs.  These modern needs have insisted that products be safer and more efficient then they were 30+ years ago.  

One example of this is EXAIR’s Vortex Tube. Vortex tubes where discovered in 1931 and were exposed to industrial manufacturing in 1945. EXAIR improved upon them when the company began in 1983. Today they are still used for various cooling applications such as replacing mist coolant on CNC machines, cooling down plastic parts during ultrasonic welding, and keeping electrical cabinets cool so they don’t overheat.

Another example is air nozzles, nozzles are used for many different purposes like cleaning or cooling parts. If you are using nozzles from 30 years ago because they are effective, there is a good chance you can improve you r efficiency and increase safety for your personnel with EXAIR’s engineered Super Air Nozzles. They are designed in a variety of styles to fit your needs from tiny micro nozzles to massive cluster nozzles to blow off or cool  a multitude of parts and processes. 

Sub-zero air flow with no moving parts. 3400 Series Vortex Tubes from EXAIR.

If you have any questions about compressed air systems or want more information on any of EXAIR’s products, give us a call, we have a team of Application Engineers ready to answer your questions and recommend a solution for your applications.

Cody Biehle
Application Engineer
EXAIR Corporation
Visit us on the Web
Follow me on Twitter
Like us on Facebook

The Makeup of Earth’s Air

Most people know that oxygen, makes up about 20% of the earth’s atmosphere at sea level, and that almost all the rest is nitrogen. But did you know there’s an impressive list of other gases in the air we breathe

whats in air
Reference: CRC Handbook of Chemistry and Physics, edited by David R. Lide, 1997.

We can consider, for practical purposes, that air is made up of five gases: nitrogen, oxygen, argon, carbon dioxide, and water vapor. But because water vapor is a variable, this table omits it, water vapor generally makes up 1-3% of atmospheric air, by volume, and can be as high as 5%.  Which means that, even on a ‘dry’ day, it pushes argon out of third place!

There are numerous reasons why the volumetric concentrations of these gases are important.  If oxygen level drops in the air we’re breathing, human activity is impaired.  Exhaustion without physical exertion will occur at 12-15%.  Your lips turn blue at 10%.  Exposure to oxygen levels of 8% or below are fatal within minutes.

But here at EXAIR we care about how compressed air can be used efficiently to better your process! 

Any of our products are capable of discharging a fluid, but they’re specifically designed for use with compressed air – in basic grade school science terms, they convert the potential energy of air under compression into kinetic energy in such a way as to entrain a large amount of air from the surrounding environment.  This is important to consider for a couple of reasons:

  • Anything that’s in your compressed air supply is going to get on the part you’re blowing off with that Super Air Nozzle, the material you’re conveying with that Line Vac, or the electronics you’re cooling with that Cabinet Cooler System.  That includes water…which can condense from the water vapor at several points along the way from your compressor’s intake, through its filtration and drying systems, to the discharge from the product itself.
  • Sometimes, a user is interested in blowing a purge gas (commonly nitrogen or argon) –  but unless it’s in a isolated environment (like a closed chamber) purged with the same gas, most of the developed flow will simply be room air.

Another consideration of air make up involves EXAIR Gen4 Static Eliminators.  They work on the Corona discharge principle: a high voltage is applied to a sharp point, and any gas in the vicinity of that point is subject to ionization – loss or gain of electrons in their molecules’ outer valences, resulting in a charged particle.  The charge is positive if they lose an electron, and negative if they gain one.  Of the two gases that make up almost all of our air, oxygen has the lowest ionization energy in its outer valence, making it the easier to ionize than nitrogen.  You can certainly supply a Gen4 Static Eliminator with pure nitrogen if you wish, but the static dissipation rate may be lesser.

If you want to learn more about the compressed air or any of our point of use compressed air products, you can contact an Application Engineer.  We will be happy to help you.

Jordan Shouse
Application Engineer

Send me an email
Find us on the Web 
Like us on Facebook
Twitter: @EXAIR_JS

Air photo courtesy of Barney Moss Creative Commons License