Experimental investigation on vibro-acoustic techniques to detect and locate leakages in gas pipelines

Leak detection and location are critical for the safety management of gas pipelines. Vibro-acoustic techniques have been proven to be effective. However, no single study exists, which examined the performance of different kinds of sensors in buried large-diameter gas pipelines. This paper presents an experimental investigation that concerns the feasibility of vibro-acoustic techniques in buried large-diameter gas pipelines for leak detection and location. A test rig was set up, and acoustic sensors and accelerometers were employed to measure the leak noise. This experiment confirmed that both acoustic sensors and accelerometers can be applied to detect and locate leakages in unburied gas pipelines under certain conditions. However, the acceleration responses were quickly corrupted by the existence of backfill soil, while acoustic sensors achieved satisfactory results. The evidence from this study suggests that the acoustic sensor is more suitable for buried large-diameter gas pipelines and this is encouraging for the development of a long-distance monitoring system.