How Does Oil Free Screw Air Compressor Work? What Do You Know About Its Mechanism?

The oil-free air compressor is a type of compressor that works without needing oil. This means these compressors don’t need oil to lubricate their parts like other types of compressors. For other compressors, oil is a basic need for producing the lubrication between rotors. They don’t work well without oil.

Oil-free air compressors use other materials or things for working. Self-lubricating rotors may also be used for creating the lubrication but this method considers to be less reliable. Because the oil free screw air compressor does not contain the oil so the rotors do not come in contact with each other the gap between rotors is very small.

Because no oil is used in this compressor so for cooling the compressor, the water is thrown on the elements so this is considered to be a less efficient method. Because of this reason, the pressure ratio of oil-free compressors is very small as compared to other compressors.

Working Mechanism of Oil-Free Screw Air Compressor

The working principle of an oil-free screw air compressor involves some steps

1. Air Intake

The compressor receives the air from the atmosphere with the help of an intake filter the large contamination from the air would be removed and then use for further processing.

2. Compression Chamber

The air enters into the compression chamber where rotors are present these rotors play a vital role in compressing the air.

3. Compression of Air

The rotors start moving and the air trap between the rotors. It reduces the space between the rotors and causes air to be compressed. And this is how the compression process occurs without the use of oil.

4. Cooling Process:

The air temperature is increased due to heat generated during the process. To prevent overheating various techniques are used for cooling the compressor. The cold water may be thrown on the elements of the compressor for cooling purposes.

5. Discharge:

When the whole process is complete the compressed air is obtained in some tanks. And this compressed air is clean and free from oil contaminations.

Purpose of Using Oil-Free Screw Compressor

These oil-free compressors are basically designed for fulfilling the demands of industries where oil contamination is a main concern.

Because of using the oil the residue left at the end may become the cause of air pollution and this may also be harmful to sea life.

These oil-free compressors ensure the quality of end products.

So in some places, these compressors are widely in use.

Pros and Cons of Oil-Free Screw Air Compressor


Oil-free compressors are best for areas where contamination is a big issue. Like these compressors are best for small workshops etc. Here are some advantages of using oil-free screw air compressors.

Clean Air

One of the big advantages of using oil-free air compressors is that the compressed air obtained from this compressor is clean and free from contamination. This may be considered as a basic reason for using this compressor.

Less Cost

The maintenance cost of this compressor is very small. Because this is oil-free technology. No oil is used so the expenses of the oil-free compressor are non-existent.

Smaller Size

The size of an oil-free compressor is small so it can move around easily. We can keep these compressors at home or in smaller workshops.


With having advantages the oil-free compressor also has some disadvantages. These are as follows:

Noise and Heat

Because these compressors work without the use of oil so these compressors produce more temperatures and can heat up very easily.

Require More Maintenance

The compressors are small in size but required great maintenance for working well. These compressors are not suitable for working continuously. Because they can’t perform heavy duty precisely.


The oil-free screw air compressor works well without the use of oil. They don’t need the oil for lubrication and provide clean and non-contaminated air. This saves money and time therefore the demand for these compressors is high.



Cecil is a creative problem solver and experienced strategist with a passion for bringing people together to do great things. He has spent his career working in the technology industry, where he has led teams in developing innovative products and solutions.

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