LVB4361大型振动筛动态特性及试验模态研究  

Study on dynamic characteristic and modal analysis of the large LVB4361 vibrating screen

作　　者：石剑锋 SHI Jianfeng(CCTEG Tangshan Research Institute Co.Ltd.,Tangshan 063012,China;Hebei Province Coal Preparation Engineering&Technology Research Center,Tangshan 063012,China)

机构地区：[1]中煤科工集团唐山研究院有限公司,河北唐山063012 [2]河北省煤炭洗选工程技术研究中心,河北唐山063012

出　　处：《选煤技术》2024年第1期31-36,共6页Coal Preparation Technology

摘　　要：为确定大型振动筛的振动参数并验证其合理性,文章以LVB4361大型振动筛的筛箱为研究对象,通过有限元分析方法对其筛箱进行了静态、模态和谐响应分析,并应用高精度DH5922D动态信号测试分析系统对LVB4361大型振动筛的固有频率和主振型进行了现场测试。有限元分析表明:LVB4361型振动筛第8阶模态对应的固有频率为16.4Hz,与工作频率(15Hz)最为相近,二者相差9.3%,满足使用要求;第7—10阶模态对应的筛箱固有频率与工作频率较为相近,其中第7—8阶模态的振型为出料端和入料端的左右摆动,第9阶模态的振型为筛箱出料端加强梁的局部摆动,第10阶模态的振型为筛箱出料端和入料端的扭转振动;当工作频率为15Hz时,筛箱整体应力分布较均匀,高应力区主要分布在从前端数第四根横梁、第四根横梁与侧板连接处的端部,最大值为57MPa,动应力安全系数为5.42,满足振动筛许用动应力要求;筛箱位移最大为10.22mm,满足筛箱工作时对振幅的要求;大型振动筛的振动参数整体设计合理。现场测试表明:测试得到的第3阶模态的固有频率为16.362 Hz,与筛箱工作频率15 Hz相差9.08%,可避免共振;各项测试结果与有限元分析结果类似,验证了有限元法模态分析的准确性,进一步说明该大型振动筛的振动参数设计合理。有限元分析和现场测试技术的应用可有效地明确筛机振动参数及其合理性,为大型振动筛的设计可靠性提供了技术依据。In order to determine the vibration parameters of the large-size vibrating screens and verify their rationality,the sieve box of LVB4361 vibrating screen is taken as the object to make analysis of static,modal and harmonic response characteristics of the box of the screen.Meanwhile,field testing on both natural frequency and principle vibration mode is also conducted using the high-precision DH5922D dynamic signal testing apparatus.Finite-element analysis shows that the natural frequency corresponding to the 8th-order modal is 16.4 Hz which is closest to the working frequency(15 Hz)with a difference of 9.3%which can meet the requirements for application;the principle vibration mode of the 7—8th-order modal manifests itself in the form of leftward and rightward swing of the screen′s discharge and feed ends;at a working frequency of 15 Hz,the stress on the box is uniformly distributed with its peak value appearing on the fourth cross beam(counted from the front end)and on the end of the point where the fourth cross beam is connected with the side plate,with a maximum value of 57 MPa and a dynamic stress safety coefficient of 5.42, which is well below the permissible dynamic stress value;the maximum displacement of the screen box is 10.22 mm, showing a good adaptability to the amplitude of vibration;and the LVB4361 screen is proved to be rational in design. As indicated by field testing results, the measured natural frequency of the 3rd-order modality is 16.362 Hz, with a difference of only 9.08% with the working frequency of the screen box of 15 Hz, making it possible to avoid resonance during operation of the screen;the results of test on various aspects are broadly similar to those obtained through finite-element analysis, demonstrating the accuracy of the finite-element analysis, and further verifying the rationality of the design of the screen. The use of the FE analysis method and the field testing technology prove to be effective in determina-tion of vibration parameters of the screen and their design rat

关 键 词：大型振动筛 模态分析 谐响应分析 固有频率 应力分布 位移分布 

分 类 号：TD452[矿业工程—矿山机电]