AP1000核电厂局部泄漏率试验废树脂转运通道贯穿件疏水方法

Drain Method for Spent Resin Transportation Penetration in AP1000 Local Leak Rate Test

AP1000核电厂安全壳局部泄漏率试验前需要对化学与容积控制系统中的废树脂转运通道贯穿件进行疏水和吹扫。该管线在机组运行时具有高放射性且在最低处没有设计疏水阀,无法使用常规方法疏水,给管线疏水造成困难。本文基于某核电厂1号机组实践,分析比较几种疏水方法的优劣,并最终确定了先依靠重力疏水,再使用虹吸泵吸水,最后使用压缩空气吹干的方法,安全有效地解决该贯穿件的疏水难题,确保了局部泄漏率试验顺利执行。

It is necessary to drain and blow down for the penetration of Chemical and Volume Control System before containment local leak rate test in AP1000 Nuclear Power Plant. However, there is no drain valve in the lowest position because high radioactivity exists in operation condition. Normal drain methodology cannot be applied to this penetration. Based on practices in Sanmen Unit 1, advantages and disadvantages for different methods are analyzed and compared in this paper. Finally, three-step solution is used to drain： firstly drain by gravity, secondly suck water by vacuum pump and then blow down by compressed air. Using this method, the drain puzzle is handled safely and properly. Local leak rate test is performed successfully.