通用门式起重机螺栓松动模态频率识别研究  

Modal Frequency Identification of Loosening Bolts for General Gantry Crane

作　　者：庆光蔚 吴祥生 胡静波 Qing Guangwei;Wu xiangsheng;Hu Jinbo

机构地区：[1]南京市特种设备安全监督检验研究院,南京210019

出　　处：《起重运输机械》2020年第22期83-88,共6页Hoisting and Conveying Machinery

摘　　要：为了研究螺栓松动问题对门式起重机的结构力学性能影响,以梁单元模拟螺栓连接,建立了通用门式起重机金属结构有限元模型,进行了实模态仿真计算;通过螺栓全紧、半松、全松工况下的力锤激励模态实验,识别出三种连接状态下的模态频率和模态振型;实验结果与仿真结果前四阶振型能对应,验证了有限元模型的正确性;模态频率随着连接松动程度有下降现象,反映出整体刚度的降低。但频率下降幅度不明显,说明作为动力指纹,频率对局部刚度的变化不十分敏感。In order to study the effect of bolt loosening on the structural mechanical performance of the gantry crane,the finite element model of the metal structure of the general gantry crane was established by simulating the bolt connection using the beam element,and the finite element modal simulation was carried out;The hammer-excited modal experiment under the working conditions has identified the modal frequency and modal vibration modes under the 3 different connection states;The experimental results correspond to the first four modes of simulation,which verifies the correctness of the finite element model;The modal frequency decreases with the degree of connection looseness,reflecting the decrease in overall stiffness.However,the frequency decrease is not obvious,indicating that as a dynamic fingerprint,the frequency is not very sensitive to changes of local stiffness.

关 键 词：门式起重机 螺栓连接 模态频率 损伤识别 

分 类 号：TH213.5[机械工程—机械制造及自动化]