油气管道危害辨识故障树分析方法研究

Study on the ETA (Fault Tree Analysis) of Oil/Gas Pipeline Hazard Identification

建立了油气管道失效故障树,研究了故障树定性和定量分析的方法。介绍了油气管道危害辨识涉及的相关概念和管道危害识别流程,简要说明了管道危害辨识所要收集的资料和管道分段原则。根据故障树分析原理,以“管道失效”为顶事件,“穿孔”和“破裂”为次顶事件建立了油气管道失效故障树,通过对故障树的定性分析,发现引起管道失效的主要原因有第三方破坏、腐蚀、管材缺陷、自然灾害等。在油气管道失效故障树定性分析的基础上,对油气管道失效故障树进行了定量分析。提出了用改进的专家判断法来确定管段失效基本事件概率,并将模糊概率概念引入其中。利用层次分析法来确定专家意见权重,并用此权重来修正专家意见。在确定管道失效概率时,考虑到最小割集中基本事件独立性和相关性,分别建立了油气管道失效的事件独立性概率模型与事件相关性概率模型,并建立了基本事件概率重要度系数的数学模型。

Hazard identification for oil/gas pipeline can find the factors that cause the pipeline fail to realize the weak points, accordingly scientific bases can be provided for accidents causes analysis and preventive measures. Firstly,concepts and processes relative to oil/gas pipeline hazard identification are introduced: also the data needed in pipeline hazard identification and pipeline segment principle are explained briefly. Based on the Fault Tree Analysis (FTA) principles and pipeline accident types,the oil/gas pipeline Fault Tree is framed. Then,Fault Tree is analyzed qualitatively. All the Minimal Cut-Sets (MCS) are calculated by using Fussell-Vesely method and consequently main factors arousing pipeline failure are distinguished. Finally,Fault Tree is analyzed quantitatively. Promoted Expert Judgment Method (PEJM) is put forward to confirm the probabilities of basic events of pipe segments. According to the basic events independence and pertinence respectively, the pipe segment failure probability model, pipeline failure probability model and Probability Importance Index model of basic event are established. The oil/gas pipeline failure FTA is established and analyzed qualitatively. The Top Event is 'pipeline failure' and the Sub-Top Events are 'leak' and 'rupture' in this Fault Tree in which 92 basic events are involved. All the Minimal Cut-Sets (MCS) are calculated by using Fussell-Vesely method. There are 132 MCS in this Fault Tree,including 5 second order MCS and 26 fourth order MCS. Based on the analyzed qualitative analysis result,main causes arousing pipeline failure are distinguished: third destroy, corrosion, pipe material defects and natural disaster etc. Based on the qualitative analysis of oil/gas pipeline failure fault tree,its quantitative analysis is made. Promoted Expert Judgment Method (PEJM) is put forward to confirm the probabilities of basic events of pipe segments and the fuzzy probability is introduced. In this method,experts' option weights are confirmed by Analytic Hierarchy Process method and used to amend experts' options. Finally,according to the basic events independence and pertinence respectively, the pipe segment failure probability model, pipeline failure Probability model and Probability Importance Index model of basic event are established.