摘要
通过宏观检查、XRD物相分析、显微组织观察和EDS能谱分析等方法,对某火电厂330 MW锅炉水冷壁管泄漏原因进行了研究。结果表明:引起水冷壁管开裂渗漏的最终原因为氢腐蚀。管子内壁较厚的氧化层促进沉积物下氢腐蚀;管子内壁存在Cl元素,Cl^-在沉积物下聚集引起酸腐蚀;管子内壁焊缝根部成型不良,存在凹陷或凸起导致H^+、Cl^-离子和其他杂质的聚集,炉水p H值偏低,均导致氢腐蚀加速。
The leakage of water wall tube of 330 MW boiler in a thermal power plant was studied through macrography, XRD phase analysis, microstructure observation and EDS spectrum analysis. The results show that the ultimate reason caused crocking and leakage of water wall tube is hydrogen corrosion. The thick oxide layer on inner wall of tube accelerates hydrogen corrosion under sediment, the inner wall of the pipe exists Cl element, the accumulation of Cl^- in sediments causes acid corrosion. The weld root on inner wall of tube is poorly formed and it has concave or convex which causes accumulation of H^＋ ,Cl^- ions and other impurities, and the pH value of boiler water is low, which all accelerates hydrogen corrosion.
出处
《热加工工艺》
CSCD
北大核心
2017年第17期255-256,260,共3页
Hot Working Technology
关键词
水冷壁
泄漏
氢腐蚀
water-wall
leakage
hydrogen corrosion
