Top 10 tips for working with compressed air

When it comes to ensuring that a new compressor installation is as energy efficient as possible, it is essential to seek the advice of a compressed air specialist. Here Andy Jones, general manager at Mattei highlights the top 10 ways to make compressed air more efficient, more cost-effective and to ensure safety:

1. Understand your charges

It is a common misconception that compressed air is ‘free’ once the equipment has been purchased. In reality, the initial outlay makes up a very small part of the total lifetime costs of a compressor – the main cost will always be the energy required to produce the compressed air.

2. Check usage regularly

It is advisable to monitor how much compressed air you use, how much it costs and whether or not the compressor is appropriate for the application it’s been specified for you have specified it for. The best way to do this is through data logging or a detailed energy audit (in line with the forthcoming ISO 11011 standard).

3. Fixed or variable speed?

A variable speed compressor will only save you energy if there are true peaks and troughs in your demand for air, and if these variations fall within the efficient working band of the compressor. If you aren’t sure whether you are using the right compressor, data logging should help you decide.

4. Air quality

In recent years, we have seen an increase in demand for ‘oil-free’ compressors to produce ‘oil-free’ compressed air. We would advise specifiers to assess the quality of air they require using ISO 8573-1:2010 before investing in costly equipment that most probably isn’t required. In many cases, oil injected compressors with standard filtration may be sufficient. If higher purity air is required consider whether it is needed in the entire system or just in one particular area, where point of use air treatment or a dedicated smaller compressor could be used.

5. Install and site correctly

The efficiency of a compressor is dependent on the way it’s installed and where it’s sited – air flow to the compressor should be unrestricted, cool and reasonably clean; the distance from the compressor to where the compressed air is used should be kept to a minimum and pipes should be suitably sized, with as few bends as possible.

6. Check noise levels

Check the noise levels of a compressor before you buy, as you don’t want employees adversely affected by it when it’s operational. All compressor manufacturers have to state their noise levels in accordance with international standards (currently EN ISO 2151:2008 for compressors, although some manufacturers use an alternative standard).

7. Check for leaks

We frequently see compressed air systems with as many as 300 leaks and for a company using 50m³of compressed air per minute, repairing leaks could potentially save around £63,000 per annum. Leaks are simple to identify and rectify, so we would advise an annual leak detection survey be carried out and additional checks before a new compressor is installed.

8. Regular service and maintenance

If a compressed air system isn’t properly maintained it won’t run as efficiently as it should. This will increase running costs and it could be dangerous – in extreme cases, a poorly maintained compressor might catch fire or explode. This is why written schemes of examinations are a legal requirement under the Pressure Systems Safety Regulations 2000, and there is a potential fine of up to £20,000 for non-compliance.

9. Use compressed air safely

We still hear of dangerous incidents where people have used compressed air to dust off machinery, work benches and even their clothes. If compressed air penetrates the skin and gets into the bloodstream, an air bubble could reach the heart or lungs, which could be fatal. And, as it travels at a phenomenal speed, if it hits an eye or ear it may lead to blindness or loss of hearing respectively.

10. Recover heat

Compressors generate a lot of heat, and in some installations this can be recovered and put to good use in the production process for water heating, for example, or for local space heating.

Andy Jones is the general manager for Mattei, a leading manufacturer of rotary vane compressors. For further information visit www.mattei.co.uk or call 01789 450577.