SAF2205双相钢冷却器管束腐蚀穿孔的原因分析

THE REASON ANALYSIS ON THE CORROSION PERFORATION OF SAF 2205 DIPHASE STEEL COOLER BUNDLE

针对SAF2205双相钢液态烃冷却器管束在海水环境中使用时发生的穿孔泄漏故障,通过采用金相检验、扫描电镜和X射线衍射等方法,分析了故障原因。结果表明,穿孔失效的基本原因是管内壁严重结垢之后诱发缝隙腐蚀所至;而硫酸盐还原菌加速了管内结垢,进而促进了材料的缝隙腐蚀。根据分析结果提出了改进措施和建议。

In accordance with perforation leakage failure of SAF2205 diphase steel LPG cooler bundle in seawater environment service, by means of metallographic examination, scanning electron microscope (SEM) and X - ray diffract meter etc. methods , the failure reason was analyzed. The results showed that: the basic reason of perforation failure was that the serious scale occurred in the tube internal wall and then induced the crevice corrosion that caused the failure, the sulphate educing bacteria accelerated the internal scaling of tube, and promoted the crevice corrosion of material. According to the analysis results, the improvement and suggestion were proposed.