长输水管道泵站冷却系统不锈钢管道腐蚀分析与探讨

Analysis and Discussion on Stainless Steel Pipeline Corrosion of Cooling System at Pump Station of Long-distance Water Transportation Pipeline

文章针对长距离输水管道工程中泵站离心输水泵动力驱动引擎冷却水系统的不锈钢管道焊缝处出现的腐蚀问题,对奥氏体不锈钢焊接特性、焊接工艺和焊后处理进行了分析,并运用光学金相分析、电镜显微分析、能谱分析、电化学分析等方法对焊缝腐蚀区进行了试验研究,试验表明SO2-4具有抑制Cl-对不锈钢的点蚀作用,温度升高降低了不锈钢的点蚀电位,并据此提出了一些抑制和缓解腐蚀的措施与建议。

In a long-distance water transportation pipeline project,corrosion is found at the stainless steel pipeline weld of the centrifugal pump engine cooling water system at a pump station. The welding feature of austenite stainless steel,welding process and welding post-treatment are analyzed,and the experimental study on welding corrosion zone is conducted by means of optical metallographic analysis,electronical microscopic analysis,energy spectrum analysis and electrochemical analysis. The results show t hat SO2-4has the function of restraining spot corrosion from Cl-,temperature increase enables decrease of spot corrosion potential,and so on. Some measures and suggestions for restraining and retarding corrosions are put forward.