Research on Application of Leakage Monitoring Technique Based on Infrasonic Waves in Natural Gas Pipelines

Abstract In order to grasp the application effects of leakage monitoring systems based on infrasonic waves in natural gas pipelines, leakage elements with different apertures were used to carry out on-site tests in two Sichuan-Chongqing pipelines. The influences of different apertures, different operating pressures and pipeline pigging operations on the leakage monitoring systems based on infrasonic waves were compared and analyzed. The effectiveness of the key indexes of the leakage monitoring systems based on infrasonic waves was validated. The test results show that: (1) The leakage monitoring systems based on infrasonic waves could monitor leakages with apertures being 2 mm and above in both pipelines, with an average alarm response time of 66 s and an average positioning error of 10 m. (2) The pipeline operating pressures greatly influenced the key technical indexes of the systems, and the leakage apertures and positions had little influence on the signal monitoring of the systems when the operating pressures of the pipelines were higher than a certain value. (3) The pipeline pigging operations could produce obvious infrasonic wave signals, which could be captured by the systems without alarms, and leakage monitoring based on infrasonic waves has certain application prospects for positioning and monitoring during pipeline pigging. (4) Leakage monitoring based on infrasonic waves is suitable for natural gas pipelines, the key technical indexes of the leakage monitoring systems based on infrasonic waves in both pipelines met the requirements, and the overall application effect was good.