工业厂房动力机器工作平台振动疲劳性能研究

Research on Vibration Fatigue Performance of Dynamic Machine Working Platforms in Industrial Factory Buildings

以某烧结矿筛分室工作平台为研究对象,对不同工况下筛分室工作平台进行振动测试。时域及频域分析结果表明,工作平台存在共振现象且振动幅值超限。为掌握工作平台的振动疲劳性能,建立有限元模型,以实测振动数据作为激励,通过瞬态动力学分析,得到不同共振条件下平台的振动疲劳性能。将目前运行的三个工况的疲劳性能作为基准,发现当振动筛运行频率f_1与结构自振频率f_2相等时,节点振幅增大25.6%,疲劳寿命减小65.68%;当f_1与f_2相差20%时,节点振幅增大17.6%,疲劳寿命减小50.33%;当f_1与f_2相差40%时,节点振幅增大7.23%,疲劳寿命减小23.76%。

The working platform of a sinter screening room is taken as the research object. Its vibration performance is tested in different working conditions. The results of the time-domain and frequency-domain analyses show that there exists the resonance for the platform and the vibration amplitudes are overlarge. Then, the finite element model is built to study the vibration fatigue performance of the working platform. The transient dynamic analysis for finite element model is done with the load of the measured data in the vibration test as the excitation, and the fatigue performance of the working platform in different resonant conditions is obtained. The results of the fatigue performance in three kinds of working conditions show that the vibration amplitude of the node is increased by 25.6 % and the fatigue life is reduced by 65.68 % when the frequency of the vibrating screen f_1 is equal to the natural frequency of the structure f_2; the amplitude of node is increased by17.6 % and the fatigue life is reduced by 50.33 % when f_1 and f_2 differ by 20 %; the amplitude of node is increased by 7.23 %and the fatigue life is reduced by 23.76 % when f_1 and f_2 differ by 40 %.