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How to detect and fix compressed air leaks

Compressed air leaks 101

Part 2 – how to detect and fix compressed air leaks

A compressed air system with a minimum amount of leaks will be more energy efficient and more effective. Leak reduction is one of the most cost effective steps you can take to immediately reduce energy costs and improve profitability. In part 2 of our compressed air leaks 101 blog post series we look at the 3 main methods of compressed air leak detection, best practice for fixing leaks and how to manage leaks on an on-going basis.

How to detect compressed air leaks
While it may not be realistic to eliminate all leaks, it’s not actually that hard to greatly reduce them. There are 3 main ways you can detect leaks:

  1. Listen;
    A basic method is to listen for the hissing sound that leaks will make. However this requires being able to hear such noises above the sound of plant equipment. It may only therefore be possible to hear larger leaks. As you will not be able to hear all leaks, this method is far from comprehensive.
  2. Soapy water;
    Alternatively you could apply soapy water to suspected leaks. If a leak exists then then soap bubbles will form. Whilst this may be more reliable than simply listening for leaks, it is time consuming and requires that you have physical access to the entire piping system. Another drawback of this method is you have no information on the relative volume of a leak. You can therefore not make any decision on which leaks are wasting the most air and require immediate attention.
  3. Ultrasonic Leak Detection;
    The most accurate and comprehensive way to detect leaks is with an Ultrasonic Leak Detector (USLD). An USLD kit consists of directional microphones, amplifiers, and audio filters. The auditor also usually has earphones to help identify the leaks. As ultrasonic is a high frequency signal, the sound from a compressed air leak is both directional and localised to the source. This allows the detector to sense and therefore locate the source of the leak.
    Fast and accurate, a USLD is the most versatile form of leak detection and can detect leaks as small as a pinhole. It can be performed while the plant is running as background noise will not interfere with the results. In addition no physical contact with the leaks are required.

How to fix compressed air leaks
Once you have detected the air leaks the next step is to tag them – preferably with a bright and durable tag – so they can be easily found when it comes time to fix them. Information on each tag should also be logged in a spreadsheet including; location, cost of leak, potential cost savings of fixing the leak and so on. You can then prioritise the order in which leaks are fixed.

Believe it or not a number of companies will go to the efforts of undergoing a leak audit and then fail to action the findings. Without the follow-up, leak detection will become just another cost. The good news to consider is that the 80-20 Pareto Principle applies. By even just fixing 20% of the leaks, it is possible to reduce the total compressed air leakage by 80% or more.

Continual improvement
Unfortunately leak detection and repair cannot ever be a one off event. As the compressed air system ages or changes with time it may need further attention. If you want long term results then you must consider leak detection and repair as an ongoing programme. The easiest way to ensure leak detection is not forgotten is to develop a continual improvement programme. As part of this you may consider speaking to your service provider about adding leak detection to your maintenance programme. An ongoing leak detection audit and repair program will quickly pay for itself through energy savings. And, as an aside, you will likely also benefit from reduced downtime and better running production equipment.

Want to get on top of your compressed air leaks now? Find out how KAESER Compressors can help you. Click here

*McCorkle, M. Kaeser Compressors (January 2018): Compressed air system leaks whitepaper