双相不锈钢法兰侧焊缝热影响区裂纹和腐蚀问题分析

双相不锈钢法兰侧焊缝热影响区裂纹和腐蚀问题分析 Analysis of crack and corrosion in heat affected zone of flange side weld of duplex stainless steel 郑倩倩 ZHENG Qianqian 1 first-author 江苏核电有限公司 江苏核电有限公司 Jiangsu Nuclear Power Jiangsu Nuclear Power 针对某核电站海水管路系统调试期间出现泄漏的问题,从施工到调试过程,采用了多要素的排除法对腐蚀问题进行了分析。通过对材料材质性能、应力分布、材料所处介质环境等方面进行分析,得出裂纹和腐蚀为应力腐蚀,满足应力腐蚀三要素:①对材料为敏感材质;②系统某些区域采用的材料和结构不同,导致结构应力及载荷应力作用;③在腐蚀介质——海水中运行。从而达到应力腐蚀开裂条件,出现贯穿性裂纹而使介质泄漏。由于结构和所在介质环境固定,可通过更换质量符合标准要求的非敏感双相不锈钢材质的法兰解决该问题,该裂纹和腐蚀问题的分析方法可供同行借鉴。 This paper analyzes the leakage of seawater pipeline system in a nuclear power plant during commission-ing. From the construction to the commissioning process,the multi factor exclusion method is adopted to analyze the corr-osion problem. Through the analysis of material properties,stress distribution and medium environment of materials,it is concluded that cracks and corrosion are stress corrosion,which meet the three elements of stress corrosion:the material is analyzed and found to be sensitive material;the material and structure used in some areas of the system are different,which leads to the effect of structural stress and load stress;it operates in corrosive medium seawater Therefore,the condition of stress corrosion cracking is achieved,and the medium leakage is caused by the occurrence of penetrating cracks. The analysis process of the crack and corrosion can be used for reference. 不锈钢 结构应力 腐蚀介质 应力腐蚀 stainless steel structural stress corrosive medium stress corrosion TG172;TM623;TG457.11 2022-03-08 11 50