EXAIR‘s line of Adjustable and Super Air Amplifiers are the ideal solution for cooling hot parts. Using a small amount of compressed air, they’re designed to entrain massive amounts of free ambient air from the environment. This free air mixes with the primary air stream, achieving entrainment ratios of up to 25:1!
To demonstrate the dramatic difference between the Super Air Amplifier and a standard fan, I created a side-by-side video of the two. Using the 2″ Model 120022 Super Air Amplifier at just 40 PSIG (9 SCFM air consumption) check out just how effective we were at cooling down a stainless steel block:
When fast cooling of a hot part is necessary, look no further than EXAIR’s Adjustable and Super Air Amplifiers. They’re all in stock and can ship same day to the US & Canada with an order placed by 3:00 ET!
The Vortex Tube is a low cost, reliable, maintenance free way to provide cooling to a wide variety of industrial spot cooling problems.
There are two (2) popular uses for the Vortex Tubes. One is to spot cool a warm item as fast as possible. The other is to chill an item to as low a temperature as possible. Because these are very different requirements, different Vortex Tube configurations exist to handle each.
For those applications of spot cooling, we recommend the 3200 series of Vortex Tubes. They are designed to be most efficient at providing maximum refrigeration, which is a function of high cold air flow rate and moderate temperature differential of the cold air to the warm item.
And for those applications of chilling an item to a very low temperature at low flow rate , we recommend the 3400 series of Vortex Tubes. They are designed to be most efficient at providing maximum cold air temperatures, but with a lower cold air flow rate.
An important parameter for the Vortex Tubes is the Cold Fraction. By adjusting the hot valve on a vortex tube, the amount of air that is discharged through the cold end changes. When expressed as a percentage of the total compressed air that is supplied to the vortex tube, we get the Cold Fraction. For example, if the hot valve is adjusted so that for every 10 parts of compressed air supplied, we get 7 parts of cold air, then we have a 70% Cold Fraction. When you know the Cold fraction setting and the compressed air supply pressure, you can use the Vortex Tube Performance tables and get the cold air discharge temperature.
Using the table below left, at 100 PSIG compressed air pressure and a 70% Cold Fraction, we can expect the cold air discharge temperature drop to be 71°F. With 70 ° compressed air temperature, the cold air will be at -1°F.
The 3200 series of Vortex Tubes are for use in the 50-80% Cold Fraction range, and the model 3400 series is designed for use in the 20-50% Cold Fraction ranges, to maximize the performance of each.
In summary, the selection of the Vortex Tube that best meets the application needs is based on the desired cold air flow rate, and the temperature of air desired. Once these are known, using the tables can provide the information needed to select the best option.
For those applications where we are unsure what will work best, we offer the EXAIR Cooling Kits, that include a Vortex Tube (small, medium, or large) and an array of Generators, to allow the configuration of the full range of Vortex Tubes within each size family.
Model 3908 – Small Vortex Tube Cooling Kit – build models 3202, 3204, 3208, and 3402, 3404, 3408
Model 3930 – Medium Vortex Tube Cooling Kit – build models 3210, 3215, 3225, 3230, 3240, and 3410, 3415, 3425, 3430, 3440
Model 3998 – Large Vortex Tube Cooling Kit – build models 3250, 3275, 3298, 3299, and models 3450, 3475, 3498, 3499
If you have questions about Vortex Tubes or any of the 16 different EXAIR Intelligent Compressed Air® Product lines, feel free to contact EXAIR and myself or any of our Application Engineers can help you determine the best solution.
A few weeks ago, we looked at the Vortex Tube and provided a general overview of the device (see that blog here.) In a nutshell – a Vortex Tube uses an ordinary supply of compressed air as a power source, creating two streams of air, one hot and one cold – resulting in a low cost, reliable, maintenance free source of cold air for spot cooling solutions.
One of the features of the Vortex Tube is that the temperature of the cold air and the cold air flow rate is changeable. The cold air flow and temperature are easily controlled by adjusting the slotted valve in the hot air outlet.
Opening the valve (turning it counterclockwise) reduces the cold air flow rate and the lowers the cold air temperature. Closing the valve (turning it clockwise) increases the cold air flow and raises the cold air temperature.
As with anything, there is a trade off – to get higher a cold air flow rate, a moderate cold air temperature is achieved, and to get a very cold air temperature, a moderate air flow rate is achieved.
An important term to know and understand is Cold Fraction, which is the percentage of the compressed air used by the Vortex Tube that is discharged through the Cold End. In most applications, a Cold Fraction of 80% produces a combination of cold flow rate and and cold air temperature that results in the maximum refrigeration or cooling output form a Vortex Tube.
For most industrial applications – such as process cooling, part cooling, and chamber cooling, maximum refrigeration is best and the 32XX series of Vortex Tubes are preferred. For those applications where ‘cryogenic’ cooling is needed, such as cooling lab samples, or circuit testing, the 34XX series of Vortex Tube is best.
To set a Vortex Tube to a specific temperature, simply insert a thermometer into the cold air exhaust and adjust the hot valve. Maximum refrigeration, at 80% Cold Fraction, is achieved when the cold air temperature drop is 50°F (28°C) from the incoming compressed air temperature. See the video posted here for measuring and lowering and the cold air temperature.
For those cases when you may be unsure of the required cold air flow rate and cold air temperature to provide the needed cooling in an application, we would recommend an EXAIR Cooling Kit. The Cooling Kit contains a Vortex Tube, Cold Air Muffler, Air Line Filter, and a set of Generators that will allow for experimentation of the full range of air flows and temperatures possible.
I was recently contacted by an automation company using an induction heating process to heat the flared end of 2 nickel alloy parts, less than 1″ long with a 7/8″ flared end. The parts are only a few inches apart and they are heating the flared end to around 170°C and holding the temperature for about 1 second. They then cool the flared ends by using compressed air blowing through a homemade manifold with drilled holes directing the air across the parts to cool them to room temperature. The homemade manifolds were being used because they were behind schedule on the original project and needed a “quick fix”. While the current setup was working, they were using approximately 30 SCFM of compressed air with a cooling time of around 10 seconds and the operation was very loud. Looking to make some improvements to reduce the amount of air they were using, decrease the cooling cycle and lower the sound level, they turned to EXAIR for assistance.
I recommended they use our Model # 3308 Mini Cooler System with two cold outlets. The Mini Cooler incorporates a Vortex Tube and provides a 50°F temperature drop from compressed air supply temperature – in this case the outlet temperature from the Mini Cooler will be about 30°F. The dual point hose kit splits the cold airflow into two separate airstreams, allowing for a wider treatment area, or in this particular application, the ability to cool two separate parts with just one device. The unit consumes only 8 SCFM @ 100 PSIG, much less than the current 30 SCFM the customer is using now, and produces a low sound level of only 76 dBA. It also incorporates a swivel magnetic base, so installation is simple, making it easy to replace the existing setup.
If you have a cooling application you would like to discuss, please contact one of our application engineers at 800-903-9247 for assistance.
Atomizing spray nozzles atomize fluids to create a fine spray in a variety of patterns for a variety of uses. They are commonly used to mark products, paint or coat, cool, reduce dust, lubricate and clean parts.
With the numerous types of Atomizing Nozzlessold by EXAIR, it can be challenging to shift through all the information. We can help you to narrow down the field to quickly find the correct Atomizing Nozzle for your application. In a summary, here are the basic questions that need to be answered:
1.) Are you using a pressurized liquid feed?
2.) What is the viscosity of the fluid?
3.) What is the liquid feed rate in gallons per hour (gph) or liters per hour (lph).
4.) Should I use the No-Drip option?
EXAIR’s flow chart with easy-to-follow steps will walk you through the decision tree and land you at the best Atomizing Spray Nozzle for your application. In answering these simple questions, this chart will guide you to the correct page in our current catalog to get additional information and specifications. Click on Link below to determine the best nozzle for you.
When it comes to spraying a fine mist, EXAIR has a great range of Atomizing Nozzles. If you follow the flow chart, you will get the best product to spray your liquid and reduce waste. If you have any problems or questions, you can contact one of our Application Engineers at EXAIR.
Last week, I had the opportunity to work with a customer who was trying to cool a thermoformed film from 85° C (185° F) down to room temperature, 21° C (69.8° F) or low enough for the package to be handled by an operator. This container was 270 mm X 170 mm X 100 mm (10.63″ x 6.69″ x 3.94″)
In applications like this, the customer often calls in with the idea of using a Vortex Tube to produce the cold air. There are two reasons to use a different product than a vortex tube in this application. First, a vortex tube is only going to cool a small area, so to cool anything this size would take several vortex tubes. Second, the cold air is going to mix with the ambient air very quickly. When the ambient air mixes with the cold air from the vortex tube, the air will lose the cold temperature generated by the vortex tube. To counter act this mixing, we have had customers create an insulated container to hold cold air from a vortex tube close to a product, similar to a cooling tunnel. This works in some applications, but my customer had a continuously moving line. He did not have time to stop the line and install insulation around each product. He also didn’t have the length of conveyor needed to put a cooling tunnel over the line.
Instead of using the vortex tube, I suggested that he use a 12” (305 mm) Super Air Knife to cool the thermoformed container. The 12” Super Air Knife moves significantly more air than a vortex tube over the surface of the part. Thanks to the 40:1 amplification ration of the Super Air Knife, it creates more cooling to the product and use less compressed air than a series of Vortex Tubes. By mixing a large volume of free ambient air, that is the same temperature he needs to cool the part to, and a small amount of compressed air over the product they can easily cool their part to close to ambient so the operator can handle the part. The best benefit for this customer was they would not need change their manufacturing line. The air knife is the best choice when cooling a very hot, fairly flat, large surface part to a temperature close to ambient. If you need to cool a product to a temperature lower than room temperature, then a vortex tube would be a great product to do the job.
The five C’s of EXAIR products are Cooling, Cleaning, Conserving, Conveying, and Coating. All EXAIR products are suitable for applications in these areas, with varying degree of possibility. When it comes to cooling, one of the most suitable EXAIR products is the Super Air Amplifier.
An Air Amplifier can increase the volume of ambient air directed over an specific area, effectively decreasing the cooling time needed in an application. Air Amplifiers cool effectively due to the fundamental principles of convective heat transfer. In convective heat transfer, cooling capacity can be increased by increasing the temperature differential between the cooling medium and the object to be cooled, or by increasing the flow of the cooling medium.
An Air Amplifier is the best cooling choice when the material to be cooled is at an extremely high temperature. For example, in the application above, 903°C (1650°F) cylinders need to be cooled to ambient temperature as quickly as possible. Vortex Tubes are another product our customers consider for cooling applications. Vortex Tubes are the best choice when the area to be cooled is small and the temperature differential is not as large. A Vortex Tube based solution will provide very cold air, but at a lower air flow over a small area and they were not the best choice for the application in the image above.
In the same application, a Super Air Amplifier can provide large volumes of ambient air over a large area, effectively cooling the cylinders much more efficiently. The cooling can be achieved in less time, and with maximum efficiency of compressed air implementation. Air Amplifiers also offer great benefits over electric fans in this rough environment: they can withstand higher temperatures and there are no moving parts to wear or break.
If you have an application in need of efficient cooling, contact an EXAIR Application Engineer to find out if an Air Amplifier will work for you.