Parker Hannifin Manufacturing Limited Advertisement Feature
Oil-Free Compressed Air
From Any Compressor
When discussing compressed air for critical applications,
fear of oil contamination is ever present and one of the
most emotive subjects revolves around the term “oil‐free”.
Mark White, Compressed Air Treatment Applications
Manager at Parker Hannifin Manufacturing discusses the
facts regarding oil contamination in a compressed air
system and how to achieve technically oil free compressed
air, from any type of compressor.
The term “oil‐free” implies “compressed air which contains no
traces of oil” and is a very misleading term and one which is
difficult to prove or guarantee in practice.
Oil in a compressed air system will be found in 3 phases (liquid /
aerosol / vapour). The primary sources for oil are the ambient air
and the air compressor, although in older systems, oil
contaminated air receivers and distribution piping will also add to
the contamination problem.
Air compressors are constantly drawing in large volumes of
ambient air and compressing it. This ambient air contains
contamination which includes oil in a vapour phase
(hydrocarbons and Volatile Organic Compounds or VOC).
DEFRA, the Department for Environment, Food & Rural Affairs,
monitors and publishes air quality data for the UK which
highlights hydrocarbon and VOC concentrations; both for urban
and rural areas. As ambient air is compressed any contamination
present is also concentrated.
Oil can also come from the air compressor, even oil‐free variants.
And whilst an oil‐free compressor may not use oil to help
compress ambient air, oil is still used for lubricating purposes and
can end up in the downstream compressed air along with oil
from the ambient air. Even if ambient levels of oil vapour are low,
the concentration of oil in the compressed air is higher.
Oil vapour will cool and condense in the aftercooler, the air
receiver, the compressed air distribution piping and when air is
expanded for use. This results in the production of oil in a liquid,
aerosol & vapour phase, which will contaminate production
equipment, processes and products.
So, can an oil-free compressor without treatment equipment
provide or better still, guarantee oil-free compressed air?
No matter what type of air compressor is used, compressed air
treatment equipment will be required to reduce contaminants to
For many users, it is a surprise to find out that the purification
equipment required to deliver “Technically Oil-Free Air” (the term
used to describe treated compressed air) is the same, no matter
what type of compressor is used.
So, can compressed air treated with purification equipment
provide or better still, be guarantee technically oil-free
compressed air? Simply, yes.
Parker compressed air treatment solutions
Parker Hannifin has a complete range of compressed air
treatment solutions that not only treat liquid oil, oil aerosol & oil
vapour, they also treat 7 additional contaminants also found in
compressed air. Parker domnick hunter OIL‐X Coalescing filters
(grades AO & AA) and oil vapour reduction filter (grade OVR) will
provide an outlet air purity (quality) equivalent to
ISO8573‐1:2010 Class 0 (<0.003mg/m3) for total oil. Filtration
performance has also been independently validated by Lloyds
Register and is backed up by a compressed air quality guarantee.
For further information, download our White Paper “How to get
oil‐free compressed air from any compressor” available from our
support section on www.Parker.com/GSFE or contact Parker
Parker Hannifin Manufacturing Limited
Tachbrook Park Drive
Tel: 01926 317878
ISO 9001 and ISO 14001
56 AirUser 2020/21