Q&A: The need for oil-free compression

Turbomachinery Magazine, September/October 2021,

Brian Tylisz, Senior Vice President of Sales, Americas at Sullair, discusses centrifugal compressor and air compressor technology.

TELL OUR READERS ABOUT SULLAIR.

Since its founding in 1965, Sullair offers a line of portable and industrial air compressors, including Class 0 certified oil-free compressed air solutions. From scroll to rotary screw to centrifugal, the Sullair oil-free portfolio is available in powers from 2 – 30,000 hp and pressures from 15 – 725 psi. Sullair became a Hitachi Group company in 2017. The combination of two compressor OEMs brings more solutions to achieve their compressed air needs.

WHY ARE OIL-FREE COMPRESSORS NEEDED?

70% of all industries use some form of compressed air. In any industry it is used, compressed air directly or indirectly encounters the product being manufactured. In the food and beverage industry, for example, this means the packaging or containers holding the food or beverage, or the food or beverage itself. In pharmaceuticals, this means pills or bottles holding the pills, and so on. When using oil-flooded air compressors—especially if they are not well-maintained—there is a risk of oil passing through the compression chamber, making it downstream, and contacting the product. This jeopardizes the health and safety of the consumer. Therefore, an increasing number of industries—including food and beverage, pharmaceutical, automotive, medical, electronics, and power —are moving to oil-free compressed air systems.

WHAT ADVANTAGES DO OIL-FREE CENTRIFUGAL COMPRESSORS PROVIDE?

Centrifugal compressors provide superior energy efficiency for large volumes of air as advanced technology impellers are designed to match the required airflow and pressure. This means additional energy savings. They also provide low maintenance costs, as they’re designed with many non-contacting internal components. This ensures minimal maintenance needs. Additionally, all moving parts are easily inspected by removing the horizontally split gear cover. Centrifugal compressors provide Class 0 oil-free air for applications where air purity is essential.

HOW DOES THIS IMPACT COST?

Oil-free air compressors are cost-effective when looking at total lifecycle costs. They require minimal maintenance. A properly configured oil-free system lowers energy consumption. Further, many multi-national manufacturers are moving to oil-free compressed air systems to protect themselves against potentially damaging effects—such as contaminating end product, damaging production equipment, causing downtime or damaging their brand’s reputation due to the low quality of the end product and/or product rejections.

WHAT ARE YOUR T-SERIES COMPRESSORS USED FOR?

With T-Series compressors, Sullair offers six off-the-shelf integrated packages, all providing Class 0 oil-free air. Key features include titanium impellers as standard to extend the life of the compressor. An accessible horizontally split gearbox allows for quick inspection. A thrust collar design extends bearing life and increases impeller rotation stability. Additionally, an Allen-Bradley programmable logic controller (PLC) is standard on all models. Sullair T-Series compressors are primarily used in automotive, steel, glass, food and beverage, air separation, large industrial manufacturing, aircraft manufacturing, plant air for chemical, and petroleum processing.

HOW ABOUT YOUR F-SERIES COMPRESSORS?

Sullair f-series compressors are designed to meet specific needs. They are custom engineered to meet high pressure and flow applications. They produce Class 0 oil-free air. There are also custom seal designs available for specialty gases. Our f-series compressors are primarily used for steel, air separation, glass, automotive, process gas for chemical, and petroleum processing.

WHAT IS YOUR JOINT VENTURE WITH IHI?

IHI-Sullair Compression Technology is a joint venture between Ishikawajima-Harima Heavy Industries (IHI) and Sullair to design, produce, and sell advanced centrifugal compressors. We have been part of this joint venture since 2004. The line, branded Sullair powered by IHI, is supported by Sullair distributors throughout North, Central, and South America. The Sullair-IHI centrifugal line is complementary to the rest of our oil-free compressor offerings, engineered and manufactured by Sullair and Hitachi. These include the DSP Series oil-free rotary screw air compressors and SRL Series oil-free scroll air compressors. The DSP Series is supplies oil-free air reliably and efficiently. Features include an air end design optimized for efficiency, an oil mist remover that improves air quality while reducing top off requirements, and a motorized isolation valve that provides additional protection against downstream humidity (A big enemy of oil-free screw compressors).

WHAT TRENDS HAVE YOU NOTICED OVER THE PAST YEAR?

While there are currently few government regulations in place regarding the mandated use of oil-free air compressors, there is a growing push to change this in some industries. This is leading to an increase in multi-national corporations switching to an ISO 8573-1 certified class 0 oil-free compressed air system. Another trend is that as customers continue to emphasize sustainability, energy conservation lies at the forefront. The cost of energy can quickly surpass the upfront cost of an air compressor. Energy conservation favors larger centrifugal compressors.