Valve inspection with acoustic emission – what are the boundaries, what are new opportunities for predictive maintenance?


Studies show that 5-10% of industrial valves are suffering from internal leakage which can lead to economic losses, health and safety issues or potentially to contamination or environmental pollution. Acoustic emission is an established technology to inspect valves for internal leakage. Despite the successful establishment of the acoustic emission technology, current solutions have shown some limitations. These are e.g. their complexity of use, the need of trained and experienced personnel, the time required to perform analyses and the use of solely proprietary and closed devices. Experts performing inspections in the field are facing challenges such as using the right measuring points, flow noise from nearby processes, finding the right duration of measurement and interpreting the results. Research has shown that interpretation of results depends very much on experts’ know-how and reproducible results have thus been difficult to achieve. This causes difficulty for companies to use the data for further purposes, such as predictive maintenance. In order to tackle that problem, Senseven has taken over 1000 measurements in laboratories together with more than 10 different valve manufacturers during the last year. To replicate real production situations, leakages were also simulated in the field, taking into account different media/pressures/different valve sizes/nominal diameters and valve types. The experience gained and the data collected were used to build a digital and smart inspection system based on an artificial neural network. The challenge was to build a system that could generate reproducible results, analyze data automatically and store it in such a way that companies could use it for predictive maintenance purposes. In our technical paper session, we would like to discuss the advantages of using acoustic emission for valve inspection as well as outline the current challenges companies and inspection service providers face when performing measurements. We will discuss our findings from the field simulations and present our artificial intelligence approach for automatic leak detection and leak rate estimation. In addition, we will demonstrate our Acoustic Emission Platform and how it helps companies collect and store acoustic emission data in a structured and organized manner, taking another step towards a more efficient testing process. EWGAE 35, Ljubljana, Slovenia, 13th – 16th Sep. www.ewg
