Oil Pipeline Leak Detection Technology

As one of the most important five means to transportation, pipeline transportationhas become the artery of national economy and modern enterprise. With thedevelopment of pipeline industry, over 50% of the crude oil transported pipelines inthe world have served for more than 30 years. And a considerable portion of thedomestic crude oil transported pipelines have been in service of more than 20 years inour country. As a result of serious pipelines' aging, inevitable erosion, abrasion andhuman destroying, pipelines'leakage occurs frequently, which not only affects thenormal production , but also courses great loss of oil. It can even lead to seriouspollution to the environment and considerable losses of lives and properties.Therefore, leak detection has become a significant part of pipelines' malfunctionsdetection. In order to reduce losses and the danger that might be caused, it isnecessary to detect the occurrence of leak immediately and locate the exact leakposition. Though several leak detecting methods are available, they are not ideal inapplication scope, including responses speed and accuracy of leak localization. In thisdissertation, according to the conditions of pipeline transportation in our country,research is carried out on crude oil transported pipelines leak detection and locationtheory and the study on its supervisory system is given. In this dissertation the mainwork accomplished can be summed up as the following aspects: the wavelettransform is used to get the featured inflection point of negative pressure wave, thetime-scale property of continuous wavelet transform is utilized to detect thesingularity of signals, which can detect the signal edge under a strong noisebackground effectively. Based on transient model, this paper researched a new methodto detect leakage, which improved the difference scheme of traditional typical linemethod, and implemented real time emulation from pipeline's head end to tail end andfrom tail end to head end. Then compare the result of two emulations to judgewhether or not there is leakage, and confirm the leak location.