酸性水汽提装置酸性水管线开裂原因分析与应对措施

Cause analysis and countermeasures of pipeline crackingin sour water stripping unit

某公司酸性水汽提装置酸性水管线发生焊接接头开裂泄漏,为了查找管线开裂原因,对失效管线接头开展了腐蚀产物成分分析、硬度检测和金相组织分析,再选用不同焊条与20号钢进行焊接,在湿硫化氢介质中对焊接接头进行硫化物应力腐蚀开裂的敏感性评价,结果表明:在酸性水工况下,20号钢焊接时选用高强度匹配的J507焊条是管线出现硫化物应力腐蚀开裂的主要原因。通过管线开裂泄漏原因分析,提出了相应的解决措施。

In order to find out the cause of welded joints leakage of the pipeline in sour water stripping unit,studies were undertaken by means of corrosion product composition analysis,hardness test and metallographic structure analysis.Then different welding electrodes were selected for welding with No.20 steel,sensitivity assessment of sulfide stress corrosion cracking was implemented on welded joints in wet hydrogen sulfide medium.The result showed that J507 welding electrode with high strength matching was primary cause.Appropriate solutions were advised accordingly.