基于双剪屈服条件的输油管道腐蚀剩余强度可靠性研究

Study on the Residual Strength Reliability of Corroded Oil Pipeline Based on Double Shear Yield Condition

提出基于双剪屈服塑性极限条件的管道可靠性爆破压力可靠度模型,在基于剩余强度可靠性理论基础上,着重分析随机参数,即腐蚀深度、腐蚀长度和运行压力的分布情况,通过经典可靠性计算方法、JC法将非正态分布转化成标准正态分布,从而建立起基于双剪屈服条件的管道腐蚀可靠性计算模型。通过提取现场实验数据进行验算,其结果表明:双剪屈服强度理论算得的爆破压力更接近实验结果,该方法降低API579的保守性,大大提高了可靠性的计算精度。

The pipe explosion pressure reliability model based on double-shear yield plasticity limit condition was put forward. Some random parameters, such as corrosion depth, corrosion length and the pressure distribution, were analyzed with an emphasis based on the reliability theory of residual strength. By using JC method, which was a classic reliability calculation method and could transform the non-normal distribution into standard normal distribution, a pipe corrosion reliability calculation model based on double shear yield condition was established. Checking computations with the field experimental data indicate that the blasting pressure calculated by double shear yield strength theory is closer to the experimental results. This method decreases the conservatism of API579 and greatly enhances the calculation accuracy of reliability.