摘要
某核电站中压安注系统阀门阀瓣/阀座腐蚀断裂,严重影响为堆芯提供应急冷却的功能。为了分析腐蚀及损伤的根本原因,彻底消除机组运行隐患,通过对失效件进行宏微观实验室分析,以及点蚀倾向性试验,确认根本原因为镍基材料不耐硼酸介质腐蚀,使用该类材料的阀门存在共模现象,这是国内第一次证明在硼酸环境下用镍基合金替代钴基合金是不成功的。根据分析结果,采取替代核安全相关重要阀门,对其它阀门更换为耐硼酸腐蚀的铁基材料,并向其它核电站进行反馈,提高了机组运行的安全性及经济性。
The disc and seat of L3RIS206/208/209VP were found severely corroded and then replaced with new spare parts. In next outage, the disc and seat of L3RIS206/209VP were found severely corroded again and the disc of L3RIS208VP was broken. The above failures greatly affected the function of the safety injection system. It was necessary to analyze the root cause and take appropriate measures to eliminate the risk. By analyzing macro and micro organization of disc and seat and applying testing method to validate the corrosion tendency, the root cause was verified that the material of disc and seat was not anti-corrosion in boric acid circumstance. This is the first time in China to prove the efforts using nickel-based alloy to substitute cobalt-based alloy unsuccessful. Taking measures to replace the safety-related valves and modify the others and feedback to other nuclear plants, the safety and economy of the power station is greatly improved.
作者
王凡
Wang Fan(Daya Bay Nuclear Power Operations And Management Co.Ltd,ShenZhen Guang Dong 518124,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2019年第S01期429-434,共6页
Heat Treatment of Metals
