The Research On The Grade Of Safety Situation For City-gas PE Pipeline

In recent years,with the increase of demand for gas pipeline safety,the PE pipeline,with its unique advantage,is widely used in the town.However,different from other pipelines,the urban pipelines are under a complex and crowded environment.Once the accident occurs,the consequence is unimaginable.Therefore,improving pipeline safety has become the unremitting pursue goal of the pipeline industry.In this paper,by analyzing the risk factors influencing the safe operation of gas PE pipeline,the direct causes of the pipeline failure are obtained.Then,on the basis of suitability evaluation,referring to the classification methods of pressure vessel and industry pipeline safe situation grades,the influence factors of the safety situation for city-gas PE pipeline and their grades of safety situation have been proposed.Moreover,in order to quantitative analysis the safety situation grade of the PE pipeline,the method of comprehensive application of principle analysis,fault tree analysis(FTA),analytic hierarchy process(AHP),entropy weight method and cloud model is proposed.Apply the FTA to establish a evaluation model of the safety situation grade,then,according to the AHP and entropy weight method,determine combination weights of the safety situation influence factors.Apply cloud model to carry on comprehensive evaluation and determine the specific safety situation grade.Finally,to verify the correctness of the evaluation model,the system is applied to a gas PE pipeline in the LPG stations of Ping' an Tiand and compares with the traditional method.The result shows that the safety evaluation model can provide a practical and feasible evaluation model to the grade of safety situation of city-gas PE pipeline.