开式冷却水管腐蚀穿孔失效分析

Failure analysis on corrosion perforation in open-type cooling water pipelines

某电厂开式冷却水Q235钢管发生穿孔失效,并且有大量腐蚀坑。采用宏观检测、扫描电镜分析和化学成分分析等方法对选取的典型管样段样品进行了分析和讨论,并通过浸泡实验和水质分析对缓蚀剂的有效性进行了评价。分析结果表明,非金属夹杂和缓蚀剂无效是开式冷却水管腐蚀穿孔的主要原因。

Corrosion perforation has occured to the Q235 steel pipe used in open-type cooling water pipelines and a large number of corrosion pits have been found. Methods such as macro-analysis, chemical composition analysis and scanning electron microscopy（SEM） are used for the analysis and discussion on the typical section of a pipe sample. The effectiveness of inhibitors are assessed through immersion test and water quality analysis. The results indicate that non-metallic inclusions and invalid inhibitor are the main causes of the corrosion perforation in open-type cool- ing water pipelines.