Oil Free Screw Air Compressor: Single-Screw Water Design

The phrase "oil free screw air compressor" covers several very different machines. CMN's interpretation is specific and deliberate: a single-screw compressor lubricated and cooled by water, delivering certified oil-free air without an oil circuit. This article explains the architecture and why it matters to buyers.

Single-Screw vs Twin-Screw

Most screw compressors use two intermeshing rotors. A single-screw machine uses one main screw meshing with two star-wheels.

• Forces on the main screw are radially balanced by the two star-wheels.

• Bearing loads are lower, supporting longer life.

• Fewer rotors to machine to tight tolerances.

CMN applies water lubrication to this single-screw layout for oil-free operation.

Water as the Lubricant and Coolant

In CMN's oil free screw air compressor:

• Water is injected into the chamber to seal compression pockets.

• It cools the air immediately, holding discharge near 40–50°C.

• It keeps rotors clean, washing away fine debris.

No oil enters the chamber, so the air path stays oil-free by construction.

Performance Range

CMN's oil free screw air compressor range spans 2–40 bar, including medium-pressure PET models. Key variants:

• Fixed-speed: CM75G, CM90G, CM110G.

• PMVSD variable-speed: CM75GPV, CM110GPV, CM130GPV, CM150GPV, CM200GPV, CM242GPV, CM320GPV.

Why Buyers Choose This Design

Conclusion

An oil free screw air compressor should mean oil-free by design, not by filtration. CMN's single-screw, water-lubricated architecture delivers Class 0 air across 2–40 bar with the durability and efficiency bottling, food, pharma, and electronics plants require.

CTA: Contact CMN to discuss an oil free screw air compressor for your plant, or send specs to request a quote.