国内某电站机组首轮大修期间发现一个有牺牲阳极阴极保护的碎石过滤器表面大面积出现锈蚀。对阴极保护系统进行检查, 发现导致这一问题的原因是阳极与碎石过滤器、筒体与碎石过滤器之间都没有很好地连接, 导致阴极保护系统失效。提出了安装固定连接导电片、系统检修后重新测量点连接性改进措施。

Corrosion was found on the out surface of a debris filter which was protected by an sacrificial anode cathodic protection system in a nuclear power plant in China. After checking the whole system, it is found that the poor connections between the anode and the filter as well as the cylinder and the filter were the main reasons causing the failure of cathodic protection. Improvement measures, such as adding extra conductive pieces and measuring the conductivity after system overhaul were proposed.