Preventing leaks with condition monitoring
Published: 01 April, 2014
Whether using thermographics, ultrasonics or vibration analysis, maintenance and facilities management staff can now use sophisticated techniques to identify where problems exist and quickly prioritise the most appropriate steps of action to ensure safety. A recent EU Directive states that companies must conform to the application of best available techniques for pollution prevention and control, and Optical Gas Imaging cameras are highlighted in the Directive for their effectiveness, says Erik's Dave Manning-Ohren.
The first and last priority of safety procedure is to protect employees, but good safety practice also protects profitability and profit. When work days are lost due to workplace injury, or work-related illness, the plant suffers reduced productivity, which affects everyone, and that is one very good reason why a growing number of engineers are taking advantage of imaging cameras that can detect gas leaks in order to minimise risk.
Legislative pressure has also played its part. The EU Directive on Industrial Emissions came in to force under UK legislation at the beginning of this year. The Directive means that companies must conform to the application of best available techniques for pollution prevention and control and optical gas imaging cameras are highlighted in the Directive for their effectiveness.
In the engineering industries, which occupy some particularly aggressive environments, risks can come in many forms: gas, chemicals, molten metals, high pressure fluids, dust, extreme temperatures – the list goes on. In addition to protective clothing and accessories, safety in the engineering workplace is increasingly supported by condition monitoring tools. For example, ultrasonic equipment offers a highly effective level of defence against any malfunction that could pose a threat to safety. Steam and gas leaks, worn bearings and discharges in faulty high voltage systems can be a threat to engineers as well as productivity. In most instances these problems can be difficult to detect either visually or aurally, as any sound emitted is generally at frequencies between 20kHz and 100kHz and is therefore outside normal human hearing range. Detection is, however, relatively straightforward with the appropriate equipment, like fixed or hand held meters that essentially convert signals to the audible range and present them in the form of a graphical display. Although interpretation requires a degree of experience, the results can be remarkably accurate, especially when used in areas where there is a saturation of gases or where a wide variety of gases, pressurised vessels and vacuum processes exist.
Thermal imaging cameras have also provided an excellent means of protecting the workforce and maximising efficiency. These cameras measure infrared radiation and convert the information into visible light, with varying intensities of temperature being represented by different colours on an LCD monitor. On the factory floor, thermal imaging cameras enhance engineer safety because these lightweight, compact and robust tools can be used to record data from a safe distance even while machinery is moving.
When it comes to detecting leaks, condition monitoring has advanced to provide new solutions. Mechanical ‘sniffers’ are available that can detect and counts the parts per million of gases in the local atmosphere. However, there are difficulties. Even in stable conditions the effectiveness of these devices is limited as they can't accurately detect the source of the leak. But in windy conditions their effectiveness is reduced further. It is issues such as these that have led to the development of optical gas imaging cameras – and, of course, tougher legislation.
The EU Best Available Techniques draft reference documents state the following: "Direct visualisation of leaks is of great value to improve the efficiency of maintenance on equipment as only the leaking equipment is repaired. Another advantage... is the possibility to detect leaks under insulation and to screen from a distance, so that... emissions from components not accessible for sniffing can be located and repaired. Optical gas imaging cameras should be introduced... for easier and faster identification of significant leaking components."
Optical gas imaging cameras use the aforementioned thermographic technology to detect leaks. Because gases are opaque in the infrared wavelength, thermographic technology makes it possible for engineers to see the leak. Using high-end Optical Gas Imaging cameras a trained technician can detect more than 20 different toxic, explosive and flammable gases. In the right atmospheric conditions, even difficult to detect gases such as carbon monoxide may also be visible. High-end optical gas Imaging cameras make it possible to scan thousands of components per shift with zero downtime and, because leaks can be detected and monitored from several metres away, they are considerably safer to use.
A condition monitoring solution is only as good as the engineer that uses it and the best results from the powerful solution offered by optical gas imaging cameras is gained by trained technicians.
Gas leak detection should be integrated into a preventative maintenance schedule, with a survey carried out every 3 or 6 months, enabling enhanced safety and efficient repair. If a leak is detected, the exact source of the gas can be identified and prevented swiftly, which means less disruption to production, a fast return to normal operation and, ultimately, protected profitability.
It is also important to ensure that leak detection is incorporated as part of the standard routine after a shutdown, or after major changes to the plant, in case leaks have crept into the system, and to reinforce the case in favour of these measures, detailed reports can be prepared. A thorough condition monitoring survey from an expert supplier can offer you a comprehensive report based on their findings, fully documenting any leaks discovered, detailing the exact source of the leak. Images and videos can be used to back-up the findings of the report.
A gas leak can have a major impact on plant safety, production and the environment, so swift, accurate detection and repair is vital. Modern condition monitoring solutions such as the latest optical gas imaging cameras enable engineers to achieve that result. Maintenance and facilities management staff can use these sophisticated techniques to understand where problems exist and quickly prioritise the most appropriate steps of action to remedy a situation that can potentially result in substantial unnecessary costs and lost productivity. Just as importantly, the significant energy savings that come as a result of these advanced technologies enable businesses to work in harmony with their sustainability and corporate social responsibility initiatives, while also boosting performance and delivering considerable bottom line benefits.
For further information please visit: www.eriks.co.uk