非能动核电站辐射区域钢结构在建造期间的涂层失效分析及改进措施

Failure Analysis and Improving Measures for Passive Nuclear Plant Steel Structure Coating in Radiological Areas during Construction

在非能动核电站AP1000/CAP1000/CAP1400的设计中,涂层对辐射区域钢结构在电站寿期内的预期功能及设计基准事故(DBA)工况时的非能动冷却功能有着不可或缺的作用。根据所处区域和运行温度的不同,这些钢结构采用了不同的涂层系统。但是在建造期间,这些涂层系统表现出了与预期不同的性能且出现了局部失效现象。本文以AP1000的CA01和CA20的涂层为例,对导致涂层失效的原因进行了分析和总结,并基于现场实际情况对CAP1000/CAP1400提出了一些改进措施。

As per the design of passive nuclear plant AP1000/CAP1000/CAP1400, coating systems are essential for steel structures in radiological areas to have desired functions during the whole plant operating life and passive cooling function after design basis accident （DBA）. On the basis of locating areas and service temperatures, different coating system was applied on different steel structure. But during the construction, these coating systems cannot live up to the expected properties and even partial failure occurs therein. CA01 and CA20 of AP1000 are taken as examples in this paper. The causes of the coating systems failure are ana- lyzed. In addition, some improving measures for CAP1000/CAP1400 are provided.