摘要
42CrMoA高强连接螺栓广泛用于风机叶片与轮毂的连接,风机叶片结构复杂性和运行波动性导致载荷复杂交变,长时间交变载荷会造成叶片连接螺栓高频疲劳损伤,螺栓的疲劳失效断裂是风机安全运行急需解决重要问题。以某2 MW风力机叶片42CrMoA高强连接螺栓材料为研究对象,利用PLG-50高频疲劳试验机开展不同加载条件下螺栓材料高频疲劳实验研究。研究结果表明,650 MPa载荷下6.4449×10^(6)周次后试样尚未断裂,750 MPa载荷下的试样疲劳寿命达1.0564×10^(6)周次;疲劳损伤具有多疲劳裂纹起源区特征,试样断裂是由于多源裂纹交汇后形成峰线所导致;在相同的最大应力加载下,应力振幅越高,裂纹扩展速率越大,高频疲劳寿命越低。研究结果对揭示风机螺栓损伤断裂原因和风机安全运行具有重要意义。
42CrMoA high-strength connecting bolts are widely used to connect fan blades and hubs.The load of wind turbine blade is complex and alternating for the complexity of structure and operation fluctuation.Long time alternating load causes high frequency fatigue damage of the blade connecting bolts.The fatigue failure fracture of the bolts is an important problem to be solved urgently for safe operation of the wind turbine blade.42CrMoA high-strength connecting bolts of 2 MW wind turbine blade were taken as the research objects,and the PLG-50 high-frequency fatigue testing machine was used to carry out the high-frequency fatigue test of bolts under different load conditions.The results show that the bolts have not broken after 6.4449×10^(6) cycles under a load of 650 MPa,and the fatigue life of 750 MPa is 1.0564×10^(6) cycles.Fatigue damage has the characteristics of multiple fatigue crack origin areas.Bolt fracture is caused by the formation of peak lines after the intersection of multiple source cracks.under the same maximum stress load,the higher the stress amplitude,the greater the crack growth rate,and the lower the high-frequency fatigue life.
作者
段焱森
何建军
程庆阳
蒲珉
舒忠虎
张世浩
罗光武
DUAN Yan-sen;HE Jian-jun;CHENG Qing-yang;PU Min;SHU Zhong-hu;ZHANG Shi-hao;LUO Guang-wu(Longyuan Jiangyong Wind Power Generation Co., Ltd. of CHN Energy Group, Changsha 410000, China;School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha 410114, China;Xi'an Zhongke Qihang Monitoring and Control Technology Co., Ltd., Xi'an 712000, China)
出处
《科学技术与工程》
北大核心
2021年第23期9878-9883,共6页
Science Technology and Engineering
基金
国家能源集团公司科技创新项目(HJLFD-QTHT-2020-08)。
关键词
风机叶片
高强螺栓
高频疲劳
42CRMOA钢
wind turbine blade
high-strength bolt
high-frequency fatigue
42CrMoA steel
