Air should ordinarily cost us nothing. But that certainly isn’t the case when it comes to compressed air, which – believe it or not – can be ten times more costly than electricity. That’s when you take into account: the generation, transmission, treatment and system costs. So it’s absolutely essential to make sure that your compressed air is as cost-effective as it possibly can be.

When air leaves a compressor it is hot, dirty, wet and also usually at a higher pressure than required by the equipment downstream. How dirty and how wet? Well, a typical 50 dm3/sec (100 scfm) compressor will push 4,500 litres of water and eight litres of degraded compressor oil into the airline system in a year. Not to mention countless particles of dirt.

If any of that gets into the equipment being powered, it will make it run less efficiently, work less effectively, and wear out or break down far sooner. So compressed air must be thoroughly treated to remove contaminants and reduce the pressure, and also often needs clean oil added to lubricate the equipment it is powering.

Cleaning the air

Solid particles, liquid water, water vapour, and oil all need to be removed from the air when it leaves the compressor. Water vapour originates at the compressor outlet but as the air cools it also turns to liquid and needs to be removed in both forms. Solid particles can get into the air from the atmosphere, corrosion or carbon products. Or from the mechanical fixing of the metal pipe work and system components. Some equipment, like air bearings and miniature pneumatic motors, need very fine filtration to remove them.

Norgren Air Prep

Oil is present in liquid, aerosol and vapour forms and while oil-free compressors are an option, in all likelihood standard filters, coalescing filters and vapour removal filters may be required. Some applications can operate with a certain amount of oil vapour, or aerosol contamination, and Norgren can advise on the best options. Additional downstream filters can clean the air further for specific use in particular parts of the plant or the process.

Controlling the pressure

Using pneumatic equipment, at a higher pressure than specified, causes excessive wear – with no significant increase in output. At the same time, the compressed air and the energy used to generate it are wasted. The cost-saving solution is a pressure reducing valve or a regulator

(general purpose, pilot operated, precision, or special purpose) that maintains constant outlet pressure, irrespective of inlet pressure and outlet flow.

A suitable amount of lubricant also has to be added to reduce resistance and wear in the operating equipment. Norgren invented the market leading aerosol lubricator but also offers the injection pump type, and can advise on the most appropriate for your equipment and application.

As the world leader in air preparation, Norgren offers unrivalled knowledge of the best ways to produce clean compressed air and to use it economically, effectively and safely. Wherever you need compressed air – whether in a simple factory installation, a complex medical application or something in-between – Norgren has what it takes to achieve the best possible results.