The Reciprocating Compressor: Oil-Lubricated and Oil-Free?

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1. februar 2021

Oil Lubricated AND Oil Free?

Reciprocating compressors, also known as piston compressors, are less common than the screw compressor but just as important to a production which requires compressed air from a piston compressor.

In our Know Your Air blog, we have discussed the working principle of a piston compressor, we now turn to the ins and outs of the piston. In this guide, we discuss oil-lubricated and oil-free piston compressors.

An oil-lubricated compressor's cylinders, pistons and cranks are lubricated by oil circulating in the compressor. The compressed air from an oil-lubricated reciprocal compressor contains a certain amount of residual oil, typically 10-15 mg/m³. 


Most versions of oil-free reciprocal compressors have permanently lubricated bearings. The pistons have grease-free piston rings, usually of Teflon or carbon fiber. This type of compressor typically requires more frequent replacement of bearings and piston rings than the oil-lubricated versions. In return, the compressed air is free of residual oil.


Continue reading through our compressed air guide:
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What Does Compressed Air Contain? >