腐蚀管道剩余寿命及参数灵敏度分析

Analyzing Remaining Life and Parameter Sensitivity for Pipeline Subjected to Corrosion

考虑腐蚀速率的影响,改进了计算腐蚀管道失效压力方程,建立了管道腐蚀剩余寿命预测的概率模型,采用重要抽样法对其进行模拟,并通过目标可靠度指标确定管道的剩余寿命,提出了一种新的管道腐蚀寿命预测方法,并对管道的各项参数进行灵敏度分析,讨论了这些参数变化对管道失效概率的影响,得出径向腐蚀速率为缺陷管道失效的主要因素。

Section 1 establishes a probabilistic model for predicting the remaining life of pipeline subjected to corro- sion based on failure function. Subsections 1.1, 1.2, 1.3, and 1.4 are respectively entitled ： Method for Evalua- ting Reliability of Pipeline Subjected to Corrosion （ 1.1 ）, Selection of Variables and Stochastic Variables （ 1.2 ）, Importance Sampling Method for Analyzing Reliability of Pipeline Subjected to Corrosion （ 1.3 ）, Sensitivity Analy- sis of Parameters （1.4）. The core of section 1 consists of： ＂The importance sampling method is used to calculate the failure probability. Then, the remaining life of pipeline is determined by the Calculation results. The probability model of the new method for the prediction of remaining life of corrosion pipeline is built. The sensitivity analysis is performed to identify the key parameters that influence the failure of pipeline. ＂ Section 2 presents the numerical simulation results as shown in Figs. 1, 2 and 3 ; these results and their analysis show preliminarily that the radial corrosion rate is the most important factor.