Study On Corrosion Failure Prediction And Reliability Evaluation Of Oil Transmisson Pipeline

The dissertation attempts to deal with the safety evaluation technology of transmission pipelines, focusing its attention on safety evaluation and corrosion prediction of transmission pipelines. In accordance with the prevailing codes and standards, both international and domestic, an investigation and a test have been conducted of corroded pipelines in the Daqing Oilfield to understand the characteristics and law of pipeline corrosion and failure, thus working out a safety test method, a reasonable test plan and a safety evaluation standard.Firstly, probability distribution model of pipeline corrosion failure is established through analyzing chronically accumulated data of relative pipelines. Through corrosion environment investigation of the selected typical pipeline section, corrosion-monitoring plan suitable for safety evaluation is established by testing corrosion parameters. Furthermore, statistical model is built after classifying interior and exterior corrosion conditions.Secondly, through field investigation and experiment in corrosion prediction, corrosion defect development model is established by studying on relation between pipeline corrosion and environment. Consequently, pipeline corrosion failure prediction method based on reliability is built through analyzing the development rule of limit corrosion defect dimension.Thirdly, according to the relevant standards of safety evaluation, pipeline safety evaluation method is put forward, by using former and present data as well as the results of indoor-acceleration test. Through part of indoor corrosion tests and acceleration tests, and corrosion model and parameters, the model of pipeline residual life is established.Fourthly, evaluation software suitable for the oilfield is developed on the basis of above work. Thus, pipeline corrosion prediction and safety evaluation can be combined by use of the software.Finally, the new technique limit of maintenance, an economical maintenance cycle and revaluation cycle are put forward according to the results of safety evaluation.