输气管道阀门内漏声发射多参数检测实验研究

针对输气管道阀门内漏喷流噪声声场特征复杂特点,应用声发射检测系统进行阀门内漏过程的检测实验研究,提取阀门不同内漏率下声发射信号波形频谱特征和时域、频率参数特征;应用最小二乘法拟合函数曲线,获得声发射信号特征参数与内漏率对应关系。实验结果表明,声发射信号特征参数(均方根、标准差、均值、频域峰值)与内漏率之间都存在明显对应关系,可利用声发射信号多参数分析进行阀门内漏程度评价研究,以提高内漏识别的准确度。

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 corre- sponding 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.