Industrial Utility Efficiency    

Profile: Coaire Corporation and Oil-Less Scroll Air Compressors

Compressed Air Best Practices® interviewed Sang Woo Lee, CEO of Coaire Corporation.

Sang Woo LeeSang Woo Lee, CEO of Coaire Corporation.


Good afternoon! Tell us about your background and how you got started in the compressed air industry.

I’m originally from South Korea. I moved to the United States in 1977 and served in the United States Army for six and half years. I eventually settled in Southern California in 1984. In 1986, I started a business that exported and imported Korean-made HVAC components, including scroll-type compressors for refrigeration. Over the next ten years, I learned a great deal about the advantages of scroll-type compressors in the refrigeration industry.

In 1997, I formed a three-way business partnership between myself, a fellow American, and a company in Korea called Kyungwon Century. Kyungwon at the time manufactured both rotary screw refrigeration compressors and rotary screw air compressor pumps under license from Svenska Rotor Maskiner (SRM), which is a Swedish rotary compressor pump designer and manufacturer.

In 1998, the Kyungwon refrigeration and air compressor divisions spun off from each other. The air compressor division became Coaire Technologies. At that time, I became majority shareholder of the Coaire Technologies. Ten years later, I became majority owner of Kyungwon and Coaire Corporation. Today, Coaire manufactures a full line of air compressors for industrial and commercial applications.


Why did you decide to become CEO of a company that manufactures air compressors?

I had enough experience with compressors used in refrigeration to see there was a lot of area for growth, particularly with scroll technology given that its an oil-less air compressor in addition to its efficiencies, noise level and ability to offer customers longevity. I also liked that Coaire has a long history of innovative air compressor technology. In 1968, it became the first Korean company to develop and manufacture a reciprocating air compressor. Later, it became the first Korean manufacturer of rotary screw air compressors, which occurred after it established ties with SRM to develop unique airend technology.

Since 2006, we’ve more than doubled the size of the manufacturing operation located near Seoul and we’ve grown to the point where we now sell air compressors throughout the world using numerous production sites.


Describe Coaire’s U.S. operations and how it supports customers here.

Since the late 1990s, we began assembling rotary screw air compressors at our facility in Southern California. We continue to maintain an inventory there of oil-less rotary scroll and oil-injected rotary screw compressors ready for shipment, as well as an extensive inventory of replacement parts and components.

Due to continued growth in U.S. sales, we’re opening our U.S. headquarters operation in Arlington, Tex., in early 2019, where we will partially assemble air compressors.

The Arlington location is also home base for our sales group that provides sales and service support to customers throughout the United States, Canada and Central and South America. Roeland Meyer, Coaire Director of Sales, has played a key role in our success here in North America. He’s been with us from the beginning and we’re fortunate to have him on our team given his extensive sales experience in the compressed air industry, which dates to 1975.


Please tell us about Coaire’s products and your primary focus in the marketplace.

We’re focused on delivering clean compressed air for diverse applications in a wide range of industries. It’s why we offer oil-less and oil-free technologies.

We offer our CSOF-Series of oil-less scroll air compressors in four models that range from 3 to 50 horsepower (hp). They are available as enclosed packages with a dryer, filter, and receiver tank integrated into one unit, as well as un-enclosed base-mounted units. These air compressors are ISO 8573-1 Class 0 compliant when incorporated with appropriate filters and air dryer.  

In addition to providing oil-less air, these units are extremely quiet. Our 3 HP scroll compressors, as an example, are rated to keep sound as low as 49 dBA. This belt-driven line also includes units with anywhere from two to 10 air compressors in one package, which allows for flexibility of operation in addition to optimizing the life span of the compressors. We offer these packages in sizes ranging from 3 to 50 hp. 

Coaire CSOF8

The CSOF Series of oil-less scroll compressors are available as enclosed, complete packages to provide oil-free air with minimal noise.

In keeping with our goal of providing clean compressed air, we offer our CAF Series of oil-free rotary screw air compressors that range from 50 to 400 hp. We offer belt-driven models for smaller rotary screw models. We also provide a Variable Speed Drive (VSD) option. Our rotary screws from 30 horsepower up use direct drive.

Our other main product line is our CAS Series of oil-injected rotary screw air compressors, which range from 30 to 400 hp. We offer two models, including our direct-driven CAS S air compressor, and our variable-speed drive CAS V machine.

We worked with Sweden-based Svenska Rotor Maskiner to design the CAS line of air compressors with our “alpha” profile airend. With this airend, we’ve reduced the size of the blowhole and eliminated friction between rotors, which in turn, reduces noise level and vibration. The thermal efficiency of the profile is also 9% higher than a conventional profile airend. The end result is a higher level of reliability and long life expectancy.

 Coaire Airend

Coaire’s CAS oil-injected air compressors feature an “a” profile airend, engineered for reliability and quiet operation at high speed.

Please explain why Coaire offers oil-free and oil-less air compressor technologies.

Modern oil-free rotary screw air compressors use pressurized oil to lubricate the rotor shaft bearings, which by design, means there is a very small possibility of oil contamination migrating into the compression chamber.

An oil-free rotary screw air compressor with variable speed drive is typically higher in purchase price than an oil-less scroll air compressors, but these units offer greater duty cycle, plus they deliver a higher volume of air than scroll-type air compressors. However, screw air compressors may not be suitable for many critical applications given the requirements for oil-free air, such as those found throughout the medical industry.

On the other hand, an oil-less scroll air compressor uses sealed, greased bearings located completely outside the compression chamber so there is little to no possibility to contaminate the compression chamber and compressed air with oil. A packaged unit with multiple scroll compressors also offers redundancy, which is essential in many applications. They also go a long way toward achieving energy savings with the use of sequencing control because the unit sequences the start up of the series of air compressors, which minimizes the in-rush or starting electrical current and diminishes the impact of peak load.


Where do you see growing demand for redundancy in air compressors and oil-free air?

Like other companies we see growth in the medical and pharmaceutical industries, which is why oil-less scroll air compressors are preferred if not required. Healthcare facilities in particular design their compressed air systems around the NFPA 99 (National Fire Protection Agency) Standard for Healthcare Facilities (2005 Edition). NFPA 99 defines a medical air compressor in part as a compressor that is designed to exclude oil from the air stream and compression chamber.

Given the current NFPA code and the advantage of built-in redundancy, it’s easy to see why a small scroll air compressor package with multiple compressor pumps is an attractive option to a healthcare facility. The demand for compressed air in hospitals also varies throughout each 24-hour period. The ability to bank multiple small air compressors with anywhere from 3 to 50 hp compressors offers the ability to closely match air demand by turning off unneeded air compressor horsepower, which is yet another distinct advantage because it saves energy.


Are you developing products to capture growth opportunities like these?

Yes. In fact, we’re now rounding out our oil-injected rotary screw air compressors with small models ranging from 5 to 25 HP. We call these our “mini-screw” air compressors.

In addition to medical applications there is increased demand for rotary-type air compressors in a wide range of industrial applications that require compact units in the 5 to 25 hp range. In addition to the need for compact packaging, we’re seeing that sound quality and low maintenance, along with high quality compressed air, are desirable features in many markets.


It sounds like you’ve got a lot of exciting things going on at Coaire.

We definitely do. The market timing is right for us to accelerate our efforts with new and improved products that provide efficiency, ease of maintenance and long-term reliability. Some of the products on the near horizon include a new 10 hp oil-less scroll air compressor, as well as a compressor management system and an energy management system. These types of products lead us to our primary goal, which is to help distributors become energy management leaders since selling air compressors might not be enough to succeed in today’s business environment.


Thank you Coaire for your insights.


For more information, please contact Roeland Meyer, email:; tel: 817-600-7038, or visit

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