发电厂锅炉引风机叶片断裂原因分析  

Cause Analysis of Blade Fracture of Boiler Induced Draft Fan in Power Plant

作　　者：李晓宇 岳增武 荆象阳 LI Xiao-yu;YUE Zeng-wu;JING Xiang-yang(State Grid Shandong Electric Power Research Institute,Ji'nan 250003,China;Shandong Electric Power Industry Boiler and Pressure Vessel Inspection Center Co.,Ltd.,Ji'nan 250002,China)

机构地区：[1]国网山东省电力公司电力科学研究院,山东济南250003 [2]山东电力工业锅炉压力容器检验中心有限公司,山东济南250003

出　　处：《山东工业技术》2023年第6期104-107,共4页Journal of Shandong Industrial Technology

摘　　要：某电厂锅炉引风机叶片在运行中发生断裂。本文采用宏观检查、化学成分分析、金相检验、拉伸性能试验等方法对其断裂原因进行分析。结果表明,在引风机叶片进风侧表面进行的热喷涂工艺控制不当,导致叶片的表面处理层和外涂层以及交界处产生了孔洞和缝隙等缺陷。工作时,该锅炉风机叶片长期高负荷运行。在风压、飞灰和叶片外层缺陷的共同影响下,裂纹在叶片进风侧应力集中的薄弱部位萌生,最终在交变应力的作用下发生了疲劳断裂。The blade of a boiler induced draft fan in a power plant fractured during operation.In this paper,the causes of fracture were analyzed by means of macroscopic examination,chemical composition analysis,metallographic examination,and tensile property test.The results show that the improper control of the thermal spraying process on the intake side surface of the induced draft fan blades has resulted in defects such as holes and gaps in the surface treatment layer,the outer coating,and the junction of the blades.During operation,the boiler fan blades operate at high load for a long time.Under the combined influence of wind pressure,fly ash,and defects in the outer layer of the blade,cracks initiate in the weak part of the blade where the stress concentration is concentrated at the inlet side,and eventually fatigue fracture occurs under the action of alternating stress.

关 键 词：引风机叶片 涂层 孔洞 疲劳断裂 

分 类 号：TG142.1[一般工业技术—材料科学与工程]