Study On Some Techniques Of Doubly Linked Crude Oil Transport Pipeline Leak Detection

As one of the most important five means of transportation, pipeline transportation has become the artery of national economy and modern enterprise. With the development of pipeline industry, over 50% of the crude oil transported pipeline in the world have served for more than 30 years. And a considerable portion of the domestic crude oil transported pipeline have been in service for more than 20 years. As a result of serious pipelines aging, inevitable erosion , abrasion and human destroying, pipelines' leak occurs frequently, which not only affect the normal production , but also course great loss of energy . It can even lead to considerable losses of lives and properties and serious pollution to the environment.As the demand of oil is increasing, the second pipeline is added to several important lines to raise transportation, which compose the doubly linked crude oil transported pipeline system. Compared with single pipeline, doubly linked line, which is much more complicated at function mode, introduces uncertainty to leak detection and location. After analyzing a lot of data, this paper gains the varying rules when the current mode shifts to another. Based on the single pipeline leak detection system, mode evaluation function is provided to judge which one is damaged alternatively. The system is based on negative pressure wave method, in which the precision of time synchronization influences the location accuracy evidently. GPS system, which provides accurate time signals, is adopted to unify the system time, but the response uncertainty of the unreal-time system also leads to synchronization error. Real Time Operation System is presented to design crude oil leak detection and location real-time system, in which system response latency is limited and can be evaluated. The embedded real-time Linux is presented as development platform. Some real-time scheduling methods are analyzed and adopted to construct real-time Linux. According to its function, different function module is set to different priority. Real-time system is to make sure that the module with high priority will be responded in time. Besides more accurate time synchronization and corresponding leak location accuracy, RTOS improves the system reliability and expansibility.