600MW 超临界机组循环水泵振动大的原因分析及处理

摘 要：针对潮州发电公司某台循环水泵检修后短期内振动幅值快速上升的情况，从海水电化学腐蚀机理着手，分析认为主要原因是缝隙腐蚀、电偶腐蚀、外加阴极保护电流缺失等加剧镍铬铸铁材质外筒体定位面的腐蚀速率，引起泵体可抽出部件与外筒体定位面之间配合间隙严重超标并出现偏斜，导致水泵导轴承失去支撑定位作用且动静部件不同心造成的。通过修复阴极电流保护系统，有选择性的提高外筒体局部材质等级，循环水泵振动大问题已得到解决。

关键词：循环水泵；海水腐蚀；缝隙腐蚀；电偶腐蚀；防腐蚀措施

[Abstract] According to the Chaozhou power company of a circulating pump maintenance shortly after the rapid rise of the vibration amplitude, starting from the mechanism of electrochemical corrosion of seawater, analyses that the main reason is the crevice corrosion, galvanic corrosion, cathodic protection and lack of cast iron cylinder positioning surface increased the corrosion rate, the withdrawable part between pump body to deflect, and the cylinder the positioning surface clearance of serious exceed the standard, the static and dynamic components are not concentric, resulting in water pump guide bearing lost support from. Through the repair of impressed current cathodic protection system, improve the grade of the material cylinder local selective, circulating water pump vibration problem has been resolved.

[Keywords] circulating water pump; seawater corrosion; crevice corrosion; galvanic corrosion; corrosion protection measures