某深度调峰机组水冷壁泄漏原因分析及预防  

Cause Analysis and Prevention of Water Wall Leakage in a Depth Peak-regulating Unit

作　　者：张亚凯 毕虎才 王兴 ZHANG Ya-kai;BI Hu-cai;WANG Xing(Taiyuan Branch of China Energy Science and Technology Research Institute Co.Ltd.)

机构地区：[1]国家能源集团科学技术研究院有限公司太原分公司

出　　处：《电站系统工程》2022年第6期15-18,共4页Power System Engineering

摘　　要：针对某电厂一台正在进行深调工作的燃煤机组水冷壁,从泄漏管的化学成分、宏观形貌、微观组织、裂纹形成过程等方面对该水冷壁泄漏原因进行分析。根据检测结果以及机组运行情况,该机组水冷壁管发生泄漏是由于鳍片焊接时,焊接热输入量过大,造成水冷壁原环焊缝热影响区处组织恶化。之后该机组参与深调运行,频繁升降负荷以及启停机,使水冷壁管壁温度出现频繁交变,在交变热应力作用下,组织恶化区域内部裂纹快速萌生与扩展,最终导致管壁泄漏。The leakage caused of the water-cooled wall was analyzed from the chemical composition, macroscopic morphology, microstructure, crack formation process of the leakage pipe. Based on the analysis of test results, the leakage of the water wall tube of the unit was caused by the deterioration of the structure in the heat affected zone of the original girth weld of the water wall due to the excessive welding heat input during fin welding. After that, the unit participated in the deep peak-regulation, frequent lifting load and starting and stopping. The wall temperature of the tube changes frequently. Under the action of alternating thermal stress, the crack in the microstructure deterioration zone initiates and expands rapidly, and finally leaded to the leakage of the tube wall.

关 键 词：深度调峰 水冷壁 魏氏体 组织过烧 

分 类 号：TK227[动力工程及工程热物理—动力机械及工程]