Rotary screw air compressors are also available in two primary applications: oil free and oil injected. 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 cool and lubricate the compressor elements moving parts, to cool the air being compressed in the chamber, and to help minimize leaks from returns 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 times is run through a cooler, depending on end usage.
Our G and GX oil-injected rotary screw compressors are designed for reliability and efficiency. Will operate continuously in the harshest environments, avoiding costly downtime and production delays
GA & GA+ (5-500 kW) GA VSD (37 -315 kW) GA VSD+ (7-75 kW) Our market-leading GA oil-injected rotary screw compressor delivers outstanding performance, high productivity and low cost of ownership - even in the harshest environments
GR oil-injected 2-stage air compressors provide a reliable air supply of up to 20 bar for high pressure applications in the toughest working conditions. Often used as mine compressor
You can now buy Atlas Copco compressors online! Our online store features compressors from 2-50HP, providing compressed air flows up to 250 CFM, with and without dryers.
The AQ water-injected screw compressors meet your need for pure oil-free air. They deliver best in class energy efficiency for applications that demand reliability and purity
ZR & ZT Meet our top of the range oil-free compressors that combine top technology to deliver outstanding performance for you at every level
ZE&ZA (VSD): high-performance low pressure oil-free air compressors ZE/ZA fixed and variable speed drive (VSD) low-pressure oil-fee air compressors: high quality performers with a robust design.
ZD compressor and booster combination with energy saving VSD option. Whether you need medium, high pressure or both, the ZD (VSD) high pressure screw compressor and booster delivers 100% oil-free dry air or nitrogen.
Atlas Copco Compressor Technique ISO Certificate
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Rock Hill, SC 29730
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