时变可靠性在海底油气管道失效概率中的应用研究

为提高海底油气管道风险管理能力,针对传统管道风险分析大多采用静态时不变可靠性方法的缺点,提出基于动态时变可靠性的腐蚀海底油气管道分析思路,建立了考虑时间因素的腐蚀管道失效概率模型。根据"首次穿越率"概念建立腐蚀管道穿越模型,借助随机过程理论和敏感性分析构建代表腐蚀海底油气管道结构抗力的剩余强度模型和识别影响管道可靠性的关键因素,给出了时变视角下对比附加载荷的在役管道失效概率计算方法。结果表明,随着时间推移,腐蚀速率对管道失效概率的影响最大,运行压力的增加使管道的剩余寿命与可靠性发生显著变化,而拉伸强度影响较小。

Application Study of Time-Varying Reliability in Failure Probability of Subsea Oil and Gas Pipeline

In order to improve the risk management capabilities of subsea oil and gas pipeline,in view of the shortcomings of the traditional static time-invariant reliability method for pipeline risk analysis and based on the dynamic and time-varying reliability,the idea of the analysis of the corroded subsea oil and gas pipeline is put forward and the failure probability model of corrosion pipe with time considerate is established.Based on the concept of“first passage rate”,the corrosion piping first passage model is established,with the help of the stochastic process theory and sensitivity analysis,it is constructed the residual strength model which represents the structural resistance of the corroded subsea oil and gas pipeline and the key factors which identifies the reliability of the pipeline,and then the calculation method of failure probability from a time-varying perspective is given in the case of contrasting additional loads during service.The results show that,with the passage of time,the corrosion rate has the greatest influence on the failure probability of the pipeline and the increase of operation pressure significantly changes the remaining life and reliability of the pipeline,while has little effect on the tensile strength.