How to choose between an oil-free or oil-lubricated compressor?

When choosing the type of compressor you need, your compressed air application is central. For the choice between an oil-free of oil-lubricated compressor it is important that the compressed air quality is optimal for your process.

What do I need an oil-free compressor for?

Each application requires a different compressed air quality. In air compressors, oil is used for sealing and cooling compressed air and for lubrication. The oil used also ends up in the compressed air. In many industries, the use of oil-injected compressors is an excellent choice when the oil contamination is not a problem for production or end product. The choice for an oil-lubricated compressed air compressor, such as an oil-injected screw compressor, is cheaper than an oil-free compressor. The use of compressed air conditioning equipment can remove traces of oil from the compressed air. If oil pollution is unwanted for your production however, choosing an oil-free compressors is an absolute necessity. 

The difference between Class 0 oil-free compressed air and technically oil-free compressed air

Oil-free compressors come in all sizes
When we talk about oil-free compressors, or compressors without oil, we mean compressed air compressors without lubrication in the compression chamber. When defining Class 0 oil-free compressed air and technically oil-free compressed air, we are talking about the quality of compressed air from the compression process.

The purity of compressed air is divided into classes according to the ISO 8573.1 standard. This specifies how many particles per cubic meter, as a function of the particle size, may be present in each class. There are classes for oil concentration, solid particle concentration and water concentration.

Read more about compressed air classification> Classificiation of compressed air quality

ISO 8573.1 class 1

Compressed air that complies with ISO 8573.1 class 1, which has an oil concentration of 0.01 mg / m3 at 1 bar (a) 14.5 psia and 20 ° C, is also referred to as technically oil-free compressed air.

Class 1 is the designation for an oil concentration of 0.01 mg / m3 at 1 bar (a) 14.5 psia and 20 ° C. A compressed air solution that meets these criteria is also referred to as 'technically oil-free'. Because the compressors used do use oil in their compression process, there is always the risk of contamination in production and end process.

ISO 8573.1 class 0: 100% oil-free

When a production process absolutely must comply with the strictest safety standards, then a compressed air installation compliant with ISO8573.1 class 0 is neccessary. Oil-free compressed air is applicable in food industry, laboratories, pharmaceuticals, and electronics. The choice of Class 0 compressed air, in contrast to technically oil-free compressed air, completely eliminates the risk of contamination. That means there is also no risk of damaged or contaminated end products, and no risk of downtime of your operation due to oil breakdown.

Our oil-free compressor series

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