Bifurcation Of Air – The Wonders of Science That Is The Vortex Tube

EXAIR has provided the benefits of vortex tube technology to the industrial world since 1983. Prior to that, French scientist George Ranque wrote about his discovery in 1928 calling it the tube tourbillion. But it wasn’t until German physicist Rudolf Hilsch’s research paper in 1945 on the wirbelrorhr or whirling tube, that the vortex tube entered the minds of commercial engineers. Nearly 60 years later, EXAIR is a leading provider for cooling products utilizing vortex tube technology.

More than 2,000 BTU/hr in the palm of your hand!

EXAIR Vortex Tubes produce a cold air stream down to -50° F and are a low cost, reliable, maintenance-free (there are no moving parts!) solution to a variety of spot cooling applications. These applications span a wide variety of industries and include cooling of electronic controls, soldered parts, machining operations, heat seals, environmental chambers, and gas samples. We’re always finding compelling new cooling opportunities for the vortex tubes.

How a Vortex Tube Works

So how does it produce the cooling stream? Compressed air is plumbed into the side port of the Vortex Tube where it is ejected tangentially into the internal chamber where the generator is located. The air begins flowing around the generator and spinning up to 1 million RPM toward the hot end (right side in the animation above) of the tube, where some hot air escapes through a control valve. Still spinning, the remaining air is forced back through the middle of the outer vortex. Through a process of conservation of angular momentum, the inner stream loses some kinetic energy in the form of HEAT to the outer stream and exits the vortex tube as COLD air on the other side.

The adjustable control valve adjusts what’s known as the cold fraction. Opening the valve reduces the cold air temperature and also the cold airflow volume. One can achieve the maximum refrigeration (an optimum combination of temperature and volume of flow) around an 80% cold fraction. EXAIR publishes performance charts in our catalog and online to help you dial into the right setting for your application, and you can always contact a real, live, Application Engineer to walk you through it.

EXAIR manufactures its vortex tubes of stainless steel for resistance to corrosion and oxidation. They come in small, medium and large sizes that consume from 2 to 150 SCFM and offer from 135 to 10,200 BTU/hr cooling capacity. Each size can generate several different flow rates, dictated by a small but key part called the generator. That generator can be changed out to increase or decrease the flow rate.

While operation and setup of an EXAIR Vortex Tube are easy, its performance will begin to  decrease with back pressure on the cold or hot air exhaust of over 3 PSIG. This is a key  when delivering the cold or hot airflow through tubes or pipes. They must be sized to minimize or eliminate back pressure.

The Vortex Tube is integrated into a variety of EXAIR products for specific applications, like the Adjustable Spot Cooler, the Mini Cooler, the Cold Gun Aircoolant System and our family of Cabinet Cooler Systems.

If you would like to discuss your next cooling application, please contact an Application Engineer directly and let our team lead you to the most efficient solution on the market.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

Next Level Customer Service

I recently spoke with a customer who is a casting / machining manufacturer.  They had an automated cell that was finish machining a feature on a cast aluminum part then placing it on a conveyor belt for an operator to pick up and continue processing.

The parts were placed 3 pieces wide per row and the conveyor would index with every three parts.   The operator would pick three pieces up and transfer them to another station during the machining time.  These parts were carrying residual machining coolant and debris onto the outbound conveyor.

The operator would blow them off with a handheld blow gun and all the coolant and chips would generally end up on the floor in the area causing a slip hazard.  The focus of the project is to eliminate the safety hazards and leave the parts as clean as possible for the inspection and further process.

The metal parts were positioned similar to the parts I placed in the mock up picture below.  The conveyor the customer has is an open mesh conveyor so the process will work better than if it was a solid belt like in the mock up.

The bulk of the concern from the customer was the outside of the part and they stated that anything to blow out the internal is a bonus.  The objective is to get as much coolant off as possible.   For that we recommended they span the conveyor with a Super Air Knife Kit to blow all the parts off at once.  This is mounted closely in the mock up because the customer had space restrictions.

The Super Air Knife Kit with Universal Air Knife Mounting System will firmly mount the knife over the parts and leave adjustment if needed.
The model 1103 Mini Super Air Nozzles with Stay Set Hoses of various lengths easily bend into place and hold their positioning for the side hole on each part.

Then, because the parts are always placed in the same location with the same orientation we can locate the ID hole with a Mini Super Air Nozzle on a Stay Set Hose of varying length to reach each set of parts as they come through.  Once I had the idea and the products in place I delivered the customer  a quote and dimensional CAD file for each part.

Another recommendation was to use a regulator and filter to control just the knife then operate the three nozzles off their own regulator and filter so that the forces between the two can be varied and the performance of the other is not effected.  Accompanying the models were installation sheets for each item as well.   Followed by the pictures of this mock up for their application.

Needless to say the customer was amazed that we would go to such lengths just to give them more assurance than our 30 day guarantee.  They were extremely thankful and are pleased we shipped from stock and met their installation window.

If you are looking for a creative solution, next level customer service, same day product availability, or just a nice human to talk to about compressed air, contact us.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

Quality Of A Knock Off and Racing Motorcycles

That’s right folks, the first track day of the year is getting close.  The first for this year will be held at Putnam Park Road Course, with Midwest Cafe Racers Association.  We will be heading out on Friday, April 19th, for the weekend.  The preparations already began a few weeks ago, actually over a month ago.  This year I am not only prepping my track bike, but also my friends track bike.   The best part is, I am learning more and more about his bike, and the bells and whistles that it has.

One of the many parts to prepping the bike for the track was changing out the coolant to a non-glycol based coolant, changing the tires, removing all glass / plastic from the bike.  Not to mention drilling and safety wiring the oil filler cap, oil drain plug, and oil filter.  Those are simply the necessities, we have taken it a step further and changed out some other stock parts for nicer track ready parts.  The main obstacle has been that he elected to go with a non-branded rear set foot control.  These were copies of a very large name brand rear set foot control.  Everything seemed to fit together until I went to install the shift linkage.  The linkage length should be 9″ long, the one they sent with the new set was actually 9-5/8″ long.  Because of this it actually placed the shift lever about 3″ too low and will not work.   Luckily, I have the knowledge and ability to modify things like this.  After cutting the extra length off and re-tapping the hole, the linkage is now to the correct length on the bike, and ready to go racing.

IMG_2363 IMG_2364

The point to the story is this:  my friend went with the company who said they were just as good if not better than the big name brand, yet considerably cheaper and not made locally.  In the end the quality of the product was not what they made claims of over the internet and they don’t have near the level of support that the brand name does.  After some fixing, the units will work but it could have been a costly replacement as the manufacturer of these doesn’t stand directly behind their product.

Here at EXAIR we have instilled quality into our product and customer service.  If you were to receive a part that doesn’t work, we will be here to help figure out why, and then make the correct actions to remedy your problem as fast as possible.   So don’t always believe what you read on the internet about how great some products are when they are so much cheaper than a well established, market leading brand.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF