本文在传统缺陷评定方法的基础上,考虑裂纹、载荷以及材料特性的分布规律,应用概率断裂力学理论,对某石油化工厂减压塔进料段裂纹缺陷进行了破坏概率的计算,研究了设备的安全性;同时,根据断裂力学方法和蒙特卡罗法随机抽样模拟,讨论了焊接残余应力的概率分布对压力容器可靠寿命的影响,编制了计算机程序。 Based on the traditional method of defect assessment, considering the distribution rules of cracks, loads and material properties, the probability of failure of cracking defects in the feed section of the vacuum tower of a petrochemical plant was calculated by using the theory of probability fracture mechanics. At the same time, according to the random fracture simulation method and Monte-Carlo simulation, the influence of the probability distribution of welding residual stress on the reliable life of pressure vessel is discussed and the computer program is compiled.