Gas pipeline leakage identification and location using microporous structure optical sensing cable

Abstract

Existing leakage detection systems face high costs and significant challenges in identifying and locating pinhole leakage in long-distance gas pipelines. A gas pipeline leakage monitoring model test was designed using distributed acoustic sensing (DAS) technology. The developed microporous structure optical sensing cable (MS cable) effectively slows down the attenuation of the leakage signal. A method for pipeline leakage signal identification and precise location based on fast Fourier transform (FFT) is proposed. By analyzing the vibration of the optical fiber in both time and frequency domains, leakage signals can be accurately monitored. The preliminary location of the leakage point is determined based on the variation pattern of the spectral average amplitude of each sensing channel, and an accurate leakage signal location method based on the cross-correlation algorithm is proposed, enhancing the positioning accuracy of the MS cable from 7.96 m to 0.11 m.