A Study On Pipeline Local Corrosion And Leakage Monitoring Technique

With the developing of the oil and gas pipeline, the safety of the pipeline is more and more getting people’s attention. Therefore, finding more effective real-time health monitoring methods of pipeline is the main target in the field of pipeline monitoring. In this paper, a pipeline health monitoring method based on the fiber Bragg grating sensors is presented. And the FBG strain sensor is considered to be a promising device in pipeline monitoring.The first chapter is introduction, this part summarizes the development process of the pipeline transportation, lists a series of the pipeline leakage accidents. A review of the existing pipeline corrosion and leakage monitoring technology, and analyzes its advantages and disadvantages. Focuses on the progress in the application of optical fiber sensing technology. At last, concludes with this study and research directions.To achieve the long-term and real-time monitoring in pipeline, a fiber bragg grating (FBG) hoop strain sensor is developed. This chapter introduces the pipeline local corrosion detection principle based on the new type FBG sensor. The FBG hoop strain sensor is used to measure the average hoop strain of pipeline, through which we can monitor the local corrosion of pipeline. The experimental studies of applying the FBG hoop strain sensor in detecting local corrosion is conducted on the steel pipeline to measure the average hoop strain of each section. The theory of mechanics of elasticity and the model numerical analysis based on FEM software are detailed. The results demonstrate that the FBG hoop-strain sensor has good performance in measuring the variation of the average hoop strain caused by different local corrosion degree.The third chapter introduces the pipeline leak monitoring based on FBG sensors, we installed the FBG sensors on the PPR pipeline and carried out the leakage simulation experiment. The knee point of the negative pressure wave signal is obtained by Matlab programming software. Results of the experiment show that the FBG sensors can measure the change of pipeline pressure and local the leak location. The location error decreases with the increase of pipeline length. This chapter also introduces the application of the on-line monitoring system including FBG hoop strain sensors in CNAF. The experimental studies of applying the FBG hoop strain sensor in detecting corrosion and leakage are conducted on the steel pipeline. the results show that the system can display pre-warning and locate the accident quickly as well as avoid the loss and damage.