Screw Blowers: A Comprehensive Guide to Low‑Pressure Efficiency & Reliability

Just as the rotary screw compressor is one of the backbones of the industrial world, so has the rotary screw blower evolved into one of the mainstays of the low-pressure world. Screw blowers are truly multi-faceted. They can be trusted to deliver large volumes of oil-free air, even in the roughest of conditions; typically have lower lifecycle costs due to their energy-efficient design; are easy to install; and aren’t limited to use in one application, but are able to be used in a variety of processes. Let’s learn more about the working principles and advantages of screw blowers!

Screw Blowers: How They Work

Screw blowers are a relatively recent addition to the low-pressure product portfolio, being developed out of the oil-free screw compressor technology and optimized specifically for low-pressure applications. Similar to screw compressors, the screw blower combines male and female rotors that rotate and decrease the available volume between them, which causes the air to compress. They can usually be operated more economically over a larger range of requirements. Depending on the model and provider, they can achieve operating pressures between around 0.3 and 1.5 bar.

Fun Fact: Did you know that there is a pressure range slightly above “low-pressure”? That’s right! This range is typically between 1 and 4 bar and is not handled by low-pressure blowers, but by low-pressure compressors.

Advantages of Screw Blowers

Did you know that up to 80% of the lifecycle costs of a low-pressure come from energy usage? That’s right! This is a big point in favor of choosing a screw blower, as they’re about 30% more energy efficient than traditional lobe blowers. In addition, screw blowers can employ VSD (variable speed drive), which can result in even greater energy savings. This low-pressure technology also offers a wide range of volume flow and pressure, meaning that they’re ideal for many applications. Depending on the pressure conditions, they are used in the following industries or applications:

• Pneumatic Conveyance
• Wastewater Treatment
• Aquaculture
• Combusion Air
• Packaging
• Truck and Railcar Unloading
• Oxidation Air
• Fermentation

Want to learn more about screw blowers – or low-pressure technologies in general? Visit us at www.atlascopco.com/blowers-usa!