Rotary Screw Compressors
GX 2-7 EP & G 7-15 EL Series
Rotary Screw Air Compressors
Atlas Copco’s GX and G-Series of air compressors continues our legendary history of reliability and efficiency with powerful rotary screw elements that provide a 100% duty cycle. GX and G-Series air compressors are designed to operate in extreme conditions even up to ambient temperatures of 46 C/115 F. Available in multiple configurations with an extremely small footprint and lower noise levels, Atlas Copco’s GX and G-Series affords unprecedented versatility of placement and use.
Available options include an advanced electronic controller on the G 7-15 EL, integrated after cooler, tropical thermostat, and built-in dryer on our Full Feature versions.
Rotary Screw Air Compressors
The Atlas Copco GA/GA+-Series of Rotary Screw Air Compressors offers an exemplary range of specifications and options to match your specific requirements. With precision engineering and design innovation, the GA/GA+-Series continues the long tradition of efficiency and reliability that is the Atlas Copco standard. From the harshest working conditions to optimal daily operation, the GA/GA+-Series covers the full scope of working application for your needs.
GA VSD+ Series
Variable Speed Plus, Rotary Screw Compressor
The Atlas Copco GA VSD+ Series of Rotary Screw Air Compressors continues the tradition of pioneering design by creating a high performing compressor that increases overall efficiency and significantly reduces cost. The 15% lower specific energy requirement combines with the Eco-Efficient Variable Speed Drive to create 50% energy savings for operation. The GA VSD+ also provides a 12% increase in FAD over the original GA VSD models. With an impressive list of standard features and low maintenance, the GA VSD+ is the final word in sustainable performance.
The GA VSD+ Series is also available with a wide range of options designed to help you customize it to suit specific requirements. The high ambient versions allow the GA VSD+ to operate in extreme conditions, while the optional energy recovery helps you repurpose heated water for a variety of uses. Available pre-filters, tropical thermostats, and food grade oil add to the versatility of use. Contact the Atlas Copco Sales Team today to learn more about the benefits of the GA VSD+ Series of Rotary Screw Air Compressors and discover how they can work for you.
Benefits of Rotary Screw Compressors
Rotary screw compressors typically are used for continuous, commercial and industrial applications. Here are some of the primary advantages of a rotary screw compressor:
1. Lower noise outputs to meet OSHA requirements
2. Significant reduction in weight, typically by 50 percent
3. Easier maintenance due to fewer wearing parts to maintain or replace
4. Shock-less, non-wearing compression technology
5. Simplified maintenance procedures
6. Extremely low oil-carryover (as little as 3 ppm)
7. Less overall oil consumption
8. Proven reliability in harsh environments
9. Smaller physical footprint, typically by 50 percent
10. No “unbalanced” forces, less vibration transfer
11. Less heat generation
12. Zero reduction in capacity over time
How Rotary Screw Air Compressors Work
A rotary screw air-end or element has twin rotors, male and female parts rotating in opposite directions. Air fills the space between the rotors and, as they rotate, the volume between them and the surrounding housing decreases, compressing the air into a smaller space. There are no valves, or other mechanical forces that can cause unbalance, which allows a screw compressor to operate at high speeds while combining a large flow rate with small exterior dimensions – it packs a good punch for its size.
Types of Rotary Screw Compressors
Rotary screw air compressors are also available in two primary applications: oil injected and oil-free. Here’s a breakdown:
Oil Free – External gears synchronize the position of the counter-rotating screw elements, and, because the rotors do not come in contact and create friction, no lubrication is needed within the compression chamber. As a result, the compressed air is oil-free. Precision engineering within the housing keeps pressure leakage (and drops) from the pressure side to the inlet at a minimum. And because the internal pressure ratio is limited by difference in air temperature between the inlet and discharge ports, oil-free screw compressors are frequently built with several stages and inter-stage cooling to maximize the pressure reach. The gearbox driving the mechanism does contain lubricants; oil-free refers to the compression chamber itself, and the delivered air is free of foreign contaminants beyond those found inherently in the air that passes through the intake.
Oil-Lubricated – In liquid-injected rotary screw air compressors, a liquid is injected into the compression chamber to lubricate and cool the compressor elements moving parts, to cool the air being compressed in the chamber, and to help minimize return leaks into the chamber during discharge. While oil is the most common liquid used today because of its lubricating and sealing properties, water and other polymers are sometimes used. The oil is then separated and passes through a filter and cooler before it cycles back into the process again. The compressed air can still be hot and often is ran through a cooler, depending on end usage.
Which applications should use rotary screw compressors?
Rotary screw air compressors are especially durable and can handle high volume demand for extended periods of time. If you have a high-volume, continuous commercial or industrial application, a rotary screw compressor may be right for you. Smaller jobs, like DIY projects and air for a few pneumatic hand tools, don’t require the power and flow of a rotary screw compressor. If you only need air intermittently and for low-flow applications, this type of compressor isn’t for you.
Have a sensitive application that requires pure air? Rotary screw compressors are available in oil-free versions, as well as traditional oil-injected models.
Should I buy a Piston or Rotary Screw Compressor?
Depending on the work you do and the daily total amount of time you’ll be using your compressor, you’ll need a compressor that fits your workload. Are you using your air powered tools and equipment for just a few hours or are you powering them almost constantly until day’s end? Choose a compressor that will match your duty cycle to supply the correct amount of pressure throughout the day.
A piston compressor is excellent for intermittent work such as an automotive garage where a worker may be using air tools for just part of the day. In this application a rotary screw compressor would be too large and not the optimal choice.
Rotary screw type compressors are better suited for applications with higher demand so that they can run continuously. Many rotary screw compressors are used 24/7 and are the workhorses of many manufacturers. They have become popular because of their efficiency and their ability to keep up with constant demand. They are also notably quieter than many piston compressors.