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Oil Free Compressed Air | Air Compressor Guide
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Oil Free Compressed Air

When you work in the food business, chemical plants or electronics manufacturing for example, oil-free and clean compressed air is often a must-have.

What is oil free air?

When discussing oil-free compressed air, it's essential to understand the different terms:

  • Technical free air: general term for compressed air in any application.
  • Oil-free air: air that has been compressed without the use of oil as a lubricant in the compressor chamber.
  • Class-zero oil-free air: refers to air quality that meets the most stringent ISO 8573-1 Class 0 standard, signifying no presence of oil vapor.

How To Achieve Oil-Free Air?

There are basically to ways to get oil free air:

  • Make sure oil will never enter the compressed air in the first place.
  • Filter out all the oil from the air before it leaves the compressor room, or before it enters the machine that requires oil-free air.

The first option is the safest one and produces the cleanest air. Not surprisingly, it's also the costliest one, as it requires an oil-free compressor.

Oil-free compressor are always more expensive than oil-lubricated compressors and the maintenance costs will often be higher.

The second option is a good alternative: install a cheaper oil-lubricated compressor and filter the air when it leaves the compressor. There are special oil filters that will filter out most oil from the air.

Using Oil Flooded Compressors in combination with Compressed Air Filters

So interestingly, it's possible to use oil-flooded compressors to produce oil-free air. This is achieved by using oil-removal filter systems to thoroughly cleanse the air after compression.

The resulting compressed air is of the same cleanliness as when ti was produced with a oil-free compressor.

Despite this fact, there are still a lot of advantages to using a oil-free compressor.

Advantages of Oil-Free Air Compressors

Oil-free air compressors still stand out as the superior choice.

Unlike oil-lubricated compressors, there is no risk of a complete oil-separator failure (collapse) which would send all of the compressor oil down the line. This would result in a complete overwhelm of any oil-removal filter in the system.

Although a one-time event, this would result in significant downtime, product spoilage, and possible the need to replace the whole (or part of the-) compressed air system. The oil would be impossible to completely remove from the inside of the compressed air piping system.

Oil Removal Filters: Essential for Ensuring Air Purity

Despite opting for oil-free compressor technologies, the role of filters remains a must. Filters ensure that any contaminants that might have entered through the intake or as a result of ambient air conditions are effectively removed, assuring the delivery of truly clean and safe compressed air. This includes oil vapors that might be present in ambient air.

These filters are necessary because, regardless of the compressor technology, ambient air drawn into the compressor can be contaminated with oil vapor and other pollutants which must be removed to achieve pure, oil-free compressed air.

This possibility should not be ignored. Since the compressors are often installed in a technical area, near other machinery or in an industrial area in general, the presence of traces of oil in the air is a real possibility.

Remember that because of the compressor of the air by around 7 times, the contaminants in the intake air are also 'amplified' 7 times. Add to that that big oil-free air compressors typically run non stop for 24 hours a day and suck in huge amounts of ambient air per minute.