锅炉汽包水连通管破裂失效分析

Failure Analysis of Water Connect Tube of Boiler Steam Drum

应用光学显微镜和扫描电镜等检测方法,对锅炉汽包水连通管失效原因进行了分析,结果表明是由于水连通管结构设计欠缺所致。因锅炉检修时,大气中的氧会溶解于该管弯管部位所残存的炉水里,从而形成氧的浓差腐蚀电池,并对金属表面产生氧腐蚀直到破裂。本文阐述了沟状溃疡性腐蚀机理,亦提出了水连通管的修复与建议。

The failure cause of water connect tube in the steam drum of boiler was analyzed by means of optical microscope and scanning electron microscope. The results showed that its construction designs are imperfect. This is caused by oxygen from atomsphere dissolved in residual water in bend during the overhaul. Consquenly it forms oxygen concentration cell, and will cause the oxy-gen corrosion on surface even to failure. This paper describes the mechanism of the channelling ulceribility corrosion. The repairing suggestions and for boiler vvas also introduced.