An absolutely tight compressed air network is more of a myth than reality, even with the greatest effort. Even if a little escaping air doesn’t seem dramatic at first, in the long run it can quickly become expensive. The point is: compressed air is not free.
How much leakage a company wants to allow and what is proportionate in terms of regular efforts to seal it in order to realise continuous savings becomes a crucial question. For larger compressed air networks, it is assumed that five to fifteen percent is still acceptable; anything above that should be urgently looked at more closely and renewed or significantly improved. For compressors with a poor energy balance, extensive treatment technology for the compressed air produced – and taking maintenance costs into account – a price of 3 to 4 cents and more per cubic metre of compressed air is not unusual.
Of course, quite a few operators of compressed air systems know about this and are conscious of the issue and well aware of the costs – and simply switch off the compressors in the evening or at the weekend. Problem: In the process the pressurised air tanks lose the expensively generated compressed air up to atmospheric pressure and have to be refilled daily to operating pressure. A solution, for example, with pressure-retaining valves installed for this purpose, would be relatively simple and also usually inexpensive to implement, writes Dirk Gros of Flex-Air in the trade journal ‘MM MaschinenMarkt’.
Awareness Of Costs Is The Most Important Step
Even though it may sound trivial to immediately remedy directly audible leaks, this often assures the greatest savings potential. However, if the operator is not a large consumer in terms of compressed air demand, where a permanent search for leakage is financially worthwhile, medium-sized companies quickly succumb. After all, daily work has to be done without spending the whole day looking for leaks, Gros writes in his article.
In the company, therefore, a fundamental understanding must be developed that compressed air is expensive, not free. Just as most employees are aware of the electricity costs in their own homes. Employee motivation, communication and many other aspects are therefore linked to the elimination of leakage.
Besides, in times of climate change and ‘Energiewende’, it is not just a matter of buying a machine that is as cheap as possible, but a machine that has, for example, a volumetric flow meter for compressed air installed and thus reports unusually high consumption.
This makes it evident that each company must first determine the costs of its leakage individually. The second step would then be to define the company’s own permissible leakage rate and the tolerable amount of work required to eliminate it. Once this has been achieved, the path to saving energy and money is not far away.