电厂凝汽器316L不锈钢焊管腐蚀原因分析

为了寻找某电厂凝汽器用材316L不锈钢焊管腐蚀泄漏的原因,现场取样,进行了宏观目测、水质检测、金相组织测试、腐蚀形貌及能谱分析,并将其与新材料进行了对比;同时通过加速腐蚀试验研究了固溶处理对其焊缝抗腐蚀性能的影响。结果发现,凝汽器管发生泄漏的主要原因为机组停机过程中未按照相关规程及时对凝汽器放水和保养;凝汽器焊管内循环水在大量蒸发、盐分浓缩后使Cl-浓度增加;焊管焊缝位于凝汽器管底部;对焊管合理的固溶处理可以提高焊缝的抗腐蚀性能。

某热电厂凝汽器铜管腐蚀原因分析

河北南网某热电厂循环冷却水系统补水为地表水,检修时发现凝汽器中Hn70-1B铜管有腐蚀泄漏现象。通过现场检查发现腐蚀呈一定的规律性,通过试验分析结合现场检查情况判断总结该厂凝汽器铜管腐蚀成因,并针对这些腐蚀成因提出改进措施,保证机组的安全稳定运行。

Development and Application of On-Line Corrosion Monitoring Device for Condenser Tube

This paper introduces the development and industrial application of an on-line corrosion monitoring device for condenser tubes. Corrosion sensors are made up of representative condenser tubes chosen by eddy current test, which enable the monitoring result to be consistent with the corrosion of actual condenser tubes. Localized corrosion rate of condenser tubes can be measured indirectly by a galvanic couple made up of tube segments with and without pits. Using this technology, corrosion problems can be found in time and accurately, and anticorrosive measures be made more economic and effective. Applications in two power plants showed the corrosion measurements are fast and accurate.