What Is a Centrifugal Air Compressor? How It Works and Why It’s Used in Industry

Published on by Tyler DanielLeave a comment

One thing that’s found in nearly every industrial environment is an air compressor. Compressed air is used to power tools, operate packaging and automation systems, run conveyors, control valves, and more. Pneumatic tools remain popular because they’re smaller and lighter than their electric counterparts, offer infinitely variable speed and torque, and can often be safer than electrical devices in harsh or wet environments.

To power these systems, compressed air must first be generated, and that starts with the air compressor. There are two main categories of air compressors: positive displacement and dynamic. Positive displacement compressors trap a given quantity of air in a chamber, then mechanically reduce the volume to increase the pressure. Dynamic compressors raise air pressure by accelerating continuously flowing air with a high-speed impeller. The velocity energy of the air is then converted into pressure energy.

One of the most common dynamic types used in industrial applications is the centrifugal air compressor. In a centrifugal compressor, air enters the center of a high-speed rotating impeller, which can spin at more than 50,000 RPM. The impeller’s blades fling the air outward by centrifugal force, increasing its velocity and pressure. The kinetic energy of the moving air is then converted into additional pressure as it slows down in a diffuser. Centrifugal compressors are generally used where large volumes of air are required. They can handle flows from a few hundred CFM up to 100,000 CFM or more, with most plant installations falling in the 1,000–5,000 CFM range.

According to the Compressed Air Challenge, some of the key benefits of centrifugal air compressors include their ability to deliver oil-free, contaminant-free air, and the fact that they are often supplied as complete packaged systems up to 1,000 HP. They scale well, as the cost per CFM improves as size increases, do not require special foundation requirements, and are ideal for high-volume air delivery.

Of course, there are trade-offs to consider. Centrifugal compressors have limited capacity control options, reduced efficiency at partial load, and their high rotational speeds require precision bearings and specialized maintenance. They also tend to have a higher initial purchase cost compared to smaller positive-displacement units. Despite these considerations, centrifugal air compressors remain a reliable choice for facilities that require large, continuous volumes of clean, oil-free air.

Once your facility’s air is generated, the next step is making sure it’s used efficiently. Compressed air is one of the most expensive utilities in a plant, and any wasted air means wasted energy. That’s where EXAIR’s line of engineered Air Nozzles, Safety Air Guns, Super Air Knives, and Optimization products come into play, helping you get the most from every SCFM your compressor produces. If you’re looking to improve your system’s efficiency or solve a specific application issue, contact one of our Application Engineers. We’ll help you get the most out of your compressed air system from the compressor room to the point of use.

Tyler Daniel

Application Engineer

E-mail: TylerDaniel@EXAIR.com

X: @EXAIR_TD

Image courtesy of the Compressed Air Challenge

Discover the EXAIR Mini Cooler

Published on by Jordan T ShouseLeave a comment

In the fast-paced world of manufacturing, cycle time is a key factor in profitability. With most industrial operations, as you speed up equipment, heat becomes a big factor. Whether it’s a high-speed sewing machine scorching delicate fabrics or a lens grinder building up friction on optical components, uncontrolled heat leads to defects, downtime, and frustrated operators.

Enter the EXAIR Mini Cooler—a compact, no-moving-parts cooler that delivers instant cold air to keep your small-scale operations running smoothly. If you’re tired of heat-related headaches, this device might just be your next workshop hero. What is the EXAIR Mini Cooler? The EXAIR Mini Cooler is a vortex tube-based spot cooling system designed specifically for small parts and high-speed processes where traditional cooling methods fall short. Powered solely by compressed air, it generates a focused stream of cold air at an impressive 20°F (-7°C), effectively preventing heat buildup without the need for refrigerants, electricity, or complex setups.

At its core, the Mini Cooler is engineered for portability and ease of use. Available in two primary configurations:

Each system comes complete with a swivel magnetic base for quick mounting, a manual drain filter separator to ensure clean air supply, and flexible hose kits tailored to the application. No tools required for installation—it’s ready to go out of the box.

How Does It Work? The Magic of Vortex Technology The secret sauce behind the Mini Cooler’s chill factor is EXAIR’s vortex tube technology, a simple yet ingenious principle that’s been refined over decades.

Here’s the breakdown:

  1. Compressed Air Input: Ordinary shop air (typically 80–100 psig) enters the unit.
  2. Vortex Creation: Inside the tube, the air is forced into a high-speed vortex, splitting into two streams moving in opposite directions.
  3. Heat Separation: The outer stream heats up, while the inner one cools dramatically through energy transfer—resulting in cold air exiting one end (at 20°F) and hot air from the other (which can be easily vented away).
  4. Focused Delivery: The cold stream is directed precisely via adjustable hoses and nozzles, right where you need it.

This process happens instantaneously with zero moving parts, making it maintenance-free and incredibly reliable. Unlike electric coolers that can fail under dust or vibration, the Mini Cooler thrives in harsh industrial environments.

Plus, it’s adjustable: tweak the air pressure or generator for even colder temps down to -50°F (-46°C) if your application demands it.

If you’re not sure which Cooling Product fits your needs, EXAIR Application Engineers are standing by to help specify the right one for you…give me a call.

Jordan Shouse, CCASS

Application Engineer

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External Mix Air Atomizing Spray Nozzles For High Flows, High Viscosity

Published on by Russ BowmanLeave a comment

If you’re just looking to spray water or just about any water-like liquid, you’ve got plenty of options…among them, any EXAIR Atomizing Spray Nozzle. We’d just need to find the one with the flow rate and pattern size & shape you’re looking for. That’s something we can handle in a short phone call, or if you’re a control freak, do-it-yourself-er like me, you can use the spec sheets in our Atomizing Spray Nozzles catalog section.

For applications involving liquids with higher viscosity or suspended solids, we’re going to look at our External Mix Air Atomizing Spray Nozzles. Internal Mix models are limited to liquid viscosity of 300cP or less, and you can’t use Siphon Feds for liquids with higher than 200cP viscosity. While we don’t publish a maximum viscosity for the External Mix models, we have customers who successfully use them with 800cP viscosity liquids. They also have larger internal passages for superior performance with suspended solids.

Two of my favorite examples of applications involving these elements come from the food industry — the snack food sector, specifically. The first one is from a company that makes thin, light crackers called ‘crisps’ that come in different flavors, achieved by coating them with a variety of seasonings. To make the seasonings stick, they needed to spray a light coating of oil onto the surface of the crisps, immediately prior to sprinkling the seasoning onto them, and then baking it in. And they called EXAIR for help in selecting the right Spray Nozzle.

We started our selection of the External Mix line, not only because of the viscosity of the oil (it WAS close to 300cP, which ruled out Siphon Feds, and was close to the upper limit of the Internal Mix models) but also because, with an External Mix, the liquid supply pressure ONLY affects the liquid flow rate, and the air supply pressure ONLY affects the pattern size. So, since they had a VERY specific volume of oil to apply to each crisp, they could set the liquid supply pressure accordingly, and use the air supply pressure to spread it evenly & consistently onto each piece. We know it worked because they sent us a video of it:

Model EF9040SS 14.42 GPH 1/8 NPT No Drip External Mix Narrow Angle Flat Fan Atomizing Spray Nozzle

The other one came from a food production facility as well — this time, from a bakery that wanted to spray oil with a suspension of cheese powder onto dough before baking it. And the reason that the External Mix models are best for high viscosity liquids is the same reason they’re best for liquids with suspended solids. Namely, the liquid doesn’t have to go through a cavity between the Liquid & Air Caps where resistance to flow, either from viscosity or particulate, could cause problems. Since the dough was on a 12″ wide chain conveyor, we specified a Model EB1030SS 14 GPH 1/4 NPT External Mix Wide Angle Flat Fan Pattern Atomizing Spray Nozzle. It’s a fairly continuous run, so they didn’t need (or want) the No-Drip feature to turn the spray on & off. They simply shut the pump and the compressed air off when they’re done making the cheesy dough.

External Mix Atomizing Nozzles are ideal for higher viscosity liquids, and those with suspended solids.

And now…I’m hungry! But seriously, if you need to spray liquid of any kind, EXAIR probably has a Spray Nozzle on the shelf for that…give me a call.

Russ Bowman, CCASS

Application Engineer
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BETE MaxiPass Nozzle

Published on by Al WooffittLeave a comment

Last year we announced our merger with BETE. One of the things that excited us about this partnership was our ability to enhance each other’s product offering. To that end, several BETE nozzles have been available to EXAIR customers for some time. Earlier this year, we added a wide array of BETE options to the EXAIR Catalog 36. In this blog, I want to cover the MaxiPass, or MP series of nozzles.

The MaxiPass boasts a patented design that allows for maximum free passage, ensuring top-notch clog resistance when compared to other whirl-type nozzles. This guarantees dependable performance and high energy efficiency, even when dealing with dirty or lumpy liquids. Unlike standard X-vane nozzles, the MaxiPass is crafted with two distinct S-shaped internal vanes to enhance free passage, making it super reliable even in tough situations.

MaxiPass nozzles create atomization by swirling water internally through its vanes before it exits through the orifice, resulting in medium to coarse droplet sizes. Its spray pattern is more consistent than that of spiral nozzles, ensuring even coverage across various applications.

Great for use in chemical processing, pollution control, and even some fire protection applications, there are a variety of situations where the MaxiPass nozzle will shine. The droplet size produced by the MaxiPass is particularly good at breaking up foam. My colleague, Jordan Shouse, covers how an array of MaxiPass nozzles were the perfect solution for foam suppression in his blog here.

Due to the maximum free passage, the MaxiPass is ideal when working with liquids containing large particulates, like wastewater. This also makes them a great choice for liquid cooling applications, as the MaxiPass will atomize your liquid (which increases the surface area relative to the volume) without the risk of clogging.

Available in 3/8NPT and 3/4NPT sizes, in both poly-propylene and 316SS, with spray angles of 60°, 90° and 120° (with more options available directly from BETE). Flow rates range from 0.70 GPM to over 20 GPM (depending on pressure). If you would like to discuss if the MaxiPass nozzle is right for your application, then give us a call!

Al Wooffitt
Application Engineer

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