600 MW超临界机组水冷壁管失效分析  

Failure Analysis of Water Wall Tubes in a 600 MW Supercritical Unit

作　　者：吴跃 Wu Yue(East China Electric Power Test and Research Institute, China Datang Corporation Scienceand Technology Research Institute Co., Ltd., Hefei 230088, China;Datang Boiler Pressure Vessel Inspection Center Co., Ltd., Hefei 230088, China)

机构地区：[1]中国大唐集团科学技术研究院有限公司华东电力试验研究院,合肥230088 [2]大唐锅炉压力容器检验中心有限公司,合肥230088

出　　处：《发电设备》2020年第6期427-430,共4页Power Equipment

摘　　要：对某600 MW超临界机组发生泄漏的水冷壁管进行宏观检验、金相组织检验和硬度检验。结果表明:侧墙转角部位焊接热输入过大且存在较大结构应力,在长期运行的过程中,水冷壁管在残余焊接应力和热应力等作用下,熔合线位置产生裂纹并扩展贯穿管子导致泄漏。The macroscopic examination,metallographic examination and hardness test were performed to analyze the leakage reasons of water wall tubes in a 600 MW supercritical unit.Results show that the failure was found to be caused by the penetrating cracks generated at the fusion line of the weld during long-term services under the combined action of welding residual stress and thermal stress due to too large welding heat input and structural stress existing at the corner of side wall.

关 键 词：锅炉 水冷壁 过热组织 焊接应力 结构应力 

分 类 号：TK223.3[动力工程及工程热物理—动力机械及工程] TG113.2[金属学及工艺—物理冶金]