风机叶片紧固螺栓断裂原因  

Fracture reasons of fan blade fastening bolt

作　　者：郑建军 陈浩[1] 张涛[1] 田峰[1] ZHENG Jianjun;CHEN Hao;ZHANG Tao;TIAN Feng(Inner Mongolia Electric Power Science&Research Institute,Hohhot 010020,China)

机构地区：[1]内蒙古电力科学研究院,呼和浩特010020

出　　处：《理化检验（物理分册）》2023年第3期57-60,共4页Physical Testing and Chemical Analysis(Part A:Physical Testing)

基　　金：2020年内蒙古电力科学研究院自筹科技项目(2020-ZC-03);2021年内蒙古电力科学研究院自筹科技项目(2021-ZC-03)。

摘　　要：某风场风力发电机组在运行过程中,多根叶片紧固螺栓发生断裂。采用宏观观察、化学成分分析、扫描电镜分析、金相检验、力学性能测试及有限元分析等方法,对螺栓的断裂原因进行分析。结果表明:叶片法兰与变桨轴承结合面的螺纹牙底处存在应力集中,在多方向的剪切应力及拉应力作用下,逐渐形成裂纹源;螺栓中加工刀痕及夹杂物的存在促进了裂纹的形成和扩展,最终导致螺栓发生疲劳断裂。During the operation of a wind turbine generator set in a wind farm,several blade fastening bolts broke.The fracture reasons of the bolts were analyzed by means of macroscopic observation,chemical composition analysis,scanning electron microscope analysis,metallographic examination,mechanical property test and finite element analysis.The results show that there was stress concentration at the thread root of the blade flange and pitch bearing joint surface,and under the action of multi-directional shear stress and tensile stress,the crack source gradually formed.The existence of machining tool marks and inclusions in bolts promoted the formation and propagation of cracks,and finally led to fatigue fracture of bolts.

关 键 词：叶片紧固螺栓 应力集中 疲劳断裂 加工刀痕 夹杂物 

分 类 号：TB31[一般工业技术—材料科学与工程] TK83[动力工程及工程热物理—流体机械及工程]