CMN Technology Co.,Ltd.
CMN Technology Co.,Ltd.

No Oil Water Injected Screw Air Compressor

Pure water instead of lubricating oil is used in air end for lubrication. Air end and all parts contacting with water are made of 304 food grade stainless steel. Compressed air passes TUV oil free test and also meets requirements of FDA and GMP. With no oil in the whole water injected screw compressor, maintenance is simple which only requires the replacement of air and water filter. Water injected screw compressor adopts a direct coupling method between the air end and the motor, resulting in high transmission efficiency. Due to the direct injection of water for cooling circulation, the unit operates at a very low temperature which is around 45 degrees Celsius.

Working Principle Of CMN No Oil Water Injected Screw Air Compressor

The single screw air end is composed of a main screw and two symmetrically arranged flat star wheels to form a meshing pair, installed inside the stainless steel shell. The screw's groove, the inner wall of the air end shell, and the tooth surface of the star wheel constitute the compression chamber. The motor directly drives the rotation of the screw shaft, which drives the rotation of the star wheel. The gas enters the screw groove through the suction port, undergoes compression, and is then expelled through the exhaust port on the air end shell. There are spray holes on the air end shell for injection of lubricating oil or water into the compression chamber, serving as sealing, cooling, and lubricating functions.

Air is sucked into the air end through the air filter, getting compressed in the air end. During compression, water in injected into air end to cool and lubricate. Water gas mixture then is separated in gas water separator and compressed air is discharged from the minimum pressure valve on the top of the gas water separator to the user. Water remains at the bottom of gas water separator, being cooled by the water cooler or air cooler, and goes to air end for compression again.

Water Injected Oil Free Compressor Working Principle

Industry Applications of CMN No Oil Water Injected Screw Air Compressor 

No oil air compressor finds extensive applications across various industries. In the pharmaceutical and food industries, compressed air is utilized for stirring and conveying raw pharmaceuticals or food ingredients. Compressed air is directly contacted with drugs or food, so the quality(oil content, bacterial content, dust content) is highly demanded, requiring compliance with GMP or FDA regulations. In the electronic or semiconductor industry, no oil air compressor can be used for cleaning circuit boards or conveying electronic components. Also, oil free air compressor in China can provide a pure air source for various precised instruments.


Features of CMN No Oil Water Injected Screw Air Compressor

  • Whole water injected compressor is free of any lubricating oil, ensuring absolutely oil free compressed air supply.

  • The operating temperature of the compressor is low, typically below 45 degrees Celsius.

  • Low maintenance costs, requiring only the replacement of air and water filter.

  • Isothermal compression, high efficiency with direct coupling of the air end and motor.

  • The air end rotates at a speed of only 3000 revolutions per minute, resulting in low noise and vibration.

Why chose CMN No Oil Water Injected Screw Air Compressor?


  • Life time Oil free Guaranteed

  • Stability---Stably compress your air for at least 10 years

  • Easy maintenance---No wearing parts design

If you need oil free compressed air solution, feel free to send us an inquiry!

Get in Touch with CMN Compressor
Get in Touch with CMN Compressor
Leading Compressor Manufacturer of Oil Free Air Compressor, Oil Injected Compressor, Special Gas Compressor, and
After Treatment Equipment