Air compressors are an indispensable tool in many (industrial) sectors. In this article we want to tell you all about the working principle of air compressors. What does a compressor do, exactly? And why is compressed air such a good energy source? We’ll explain.
Compressed air can - obviously - be used as a power source. It has many advantages. Compressed air is completely harmless and clean, for instance. It also has many different applications: compressed air can power tools and machines, while at the same time it can dry materials or move elements. It’s because of its cleanliness and multi-usage that compressed air is such a popular energy source in different - industrial - applications.
But in order to make use of compressed air, an external power source is needed. Compression of air needs a fixed amount of external power since it’s a purely physical process. Most compressors are powered by electric or combustion engines. Question is: how does this work?
In order to explain the working principle of air compressors, we’ll have to make the distinction between different types of compressors: reciprocating (piston) and rotary (screw) compressors.
Reciprocating (or piston) compressors compress air by using cylinders, pistons and cranks. These elements are powered by an electric or combustion engine. The air is moved into the cylinder and then compressed by the pistons. The compression can have one or more stages until the right operational pressure is reached. When the air is compressed, it moves through the cooler into the air tank.
Since reciprocating compressors have many moving parts, lubrication is essential. The MARK reciprocating compressors are oil-lubricated. This also means that the compressed air that comes from the compressor contains oil residue, typically 10 to 15 mg/m³. In some cases oil contamination is a problem. Therefore MARK compressors can be fitted with an oil filter in order to remove all oil particles from the compressed air.
Want to know more about oil filters and air dryers? Read more in our article: ‘The importance of a compressed air dryer and filter in (industrial) air compressors’.
Reciprocating (or piston) compressors are used for DIY as well as industrial sectors. The big difference is their size. Industrial piston compressors are typically used in these sectors:
Rotary (or screw) compressors have a different working principle than reciprocating compressors. Instead of compressing the air using pistons and cylinders, rotary compressors use rotating screws to start the compression. Air is forced between two roating screw elements and comes out compressed.
Since the compression of air generates heat, a cooling liquid is injected between the screws (the compression chamber). This cooling liquid (in most cases: oil) moves between the cooling chamber, liquid tanks and coolers in order to keep the operating temperature at about 80°C. After compression, the cooling liquid is separated from the compressed air in the oil separator. After going through an after-cooler, the compressed air is moved to the air tank.
Rotary (screw) compressors are useful wherever a constant flow of compressed air is needed. Some typical industries are:
Now that you know more about the working principle of air compressors you might want to know more about which compressor to choose. In this article on the various types of air compressors, you will find more information.
Want to know more about the air compressors that we have to offer? Any questions about our services? We’re glad to be of service. Just let us know and we’ll get back to you as soon as possible.
If you’re still not sure what type of air compressor you need, feel free to get in touch with our experts for personal advice. We’ll assess your situation and help you find the perfect compressor.