WOG核电厂风险指引型管道在役检查方法应用研究

摘要

为促进概率安全分析技术在核电厂管道在役检查领域的更好应用,本文介绍西屋用户集团(WOG)开发的核电厂管道风险指引型在役检查(RI-ISI)优化方法,并重点从管段失效可能性分析、后果判断、风险重要度划分等三方面分析对比了该方法与EPRI型RI-ISI方法的不同.此外,以国内某M310核电机组为例,本文基于国家安全局牵头开发的标准电厂分析风险(SPAR)模型,在国内当前技术条件基础上使用简化WOG方法完成该核电厂辅助给水系统管道环焊缝的RI-ISI优化分析.计算表明,使用WOG方法开展RI-ISI后,受检焊缝数量减少55％,而相应导致的内部事件一级概率安全分析风险增量则基本为零,可以满足NNSA-0147和NNSA-0153等技术文件中推荐的风险准则.总的结论为,使用WOG方法开展核电厂管道RI-ISI优化是可行的.%In order to promote the better application of probabilistic safety analysis technology in piping inservice inspection in nuclear power plant,in this paper,the Westinghouse Owner Group (WOG)risk-informed method for piping in-service inspection in nuclear power plant is introduced,which is compared with the one developed by Electric Power Research Institute (EPRI)mainly among piping failure possibility,piping failure consequence and piping significance.In addition,based on the standardized plant analysis risk (SPAR)model developed by National Nuclear Safety Administration(NNSA),the risk-informed optimization analysis of the piping in-service inspection on the auxiliary feedwater system is carried out in a pilot M310 nuclear power plant.The calculation result show that,the number of welds need to be inspected would be reduced by 55 percent when using WOG method to perform RI-ISI,may the increased risk is nearly zero and can comply to the risk criterion in NNSA-0147 and NNSA-0153.In a word,it is feasible to carry out risk-informed piping in-service inspection in nuclear power plant by using WOG method.