A Multi-parameter Analysis of Acoustic Emission for Gas Pipeline Valve Internal Leak Detection

Acoustic emission testing system was applied in this paper to detect the leak of gas pipeline valve.The acoustic emission signals were analyzed for complex jet noise.The waveform spectrum signature,feature parameters in time domain and frequency domain were extracted under different leak rates.Further,least square method was applied for curve fitting,and corresponding relationship was established between leak rate and feature parameters.Experimental results demonstrate that there are corresponding relationships between feature parameters(root mean square,stand deviation,average,frequency peak)and leak rates.Therefore,acoustic emission signal multi-parameter analysis can be used to detect the leak of pressurized valve and improve the accuracy of leak identification.