振动信号在跨越油气管道安全检测中的应用

跨越油气管道安全检测是油气管道保护的难点，对此提出了一种基于振动传感器的跨越油气管道意外载荷检测方法。基于阈值处理理论，构建了阈值-模极大值去噪方法，将重心频率、均方频率和频率标准差作为判断油气管道运行状态的特征参数；通过搭建长输管道振动实验系统，采用外物撞击的方法模拟跨越油气管道的意外载荷，对振动信号进行降噪处理并提取特征参数。结果表明，与传统去噪法相比，本文提出的去噪方法信噪比和计算速度获得大幅提升；管道正常运行和外物撞击状态下的振动信号的相关特征参数存在显著差异，说明了振动信号作为跨越油气管道状态监测指标的有效性；振动信号相关特征参数随着信号源与传感器距离的增加而增加，而对管道输量不敏感；流体流向对振动信号有重要影响，信号源在传感器上游时，相关特征参数显著高于信号源在传感器下游的情况。

Application of vibration signal in safety detection of cross-oil and gas pipeline

Safety detection of crossing oil and gas pipelines is a difficult point in oil and gas pipeline protection, for which a vibration sensor-based method for accidental load detection of crossing oil and gas pipelines is proposed. Based on the threshold processing theory, a threshold-mode-maximum denoising method is constructed, and the center of gravity frequency, mean square frequency and standard deviation of frequency are used as the characteristic parameters to judge the operation status of oil and gas pipelines; by building a long-distance pipeline vibration experiment system, the accidental load of crossing oil and gas pipelines is simulated by the method of foreign object impact, and the vibration signal is processed by noise reduction and the characteristic parameters are extracted. The results show that the signal-to-noise ratio and computational speed of the proposed de-noising method are greatly improved compared with the traditional de-noising method; there is a significant difference between the vibration signal under normal operation and foreign object impact, which illustrates the effectiveness of the vibration signal as an indicator for monitoring the state of crossing oil and gas pipelines; the vibration signal-related characteristic parameters increase with the increase of the distance between the signal source and the sensor, but are not sensitive to the pipeline The relevant characteristic parameters of the vibration signal increase with the distance between the signal source and the sensor, but are not sensitive to the pipeline transmission volume; the fluid flow direction has an important influence on the vibration signal, and the relevant characteristic parameters are significantly higher when the signal source is upstream of the sensor than when the signal source is downstream of the sensor.