平板式钻井液叠层筛网自由振动分析

平板式钻井液叠层筛网在钻井液振动筛上得到广泛应用，研究振动筛的结构参数和安装参数对其自由振动的影响可为振动筛和筛网的设计及使用提供依据。提出将使用螺栓绷紧方法安装的筛网模型简化为弹性支承多跨单向连续矩形薄板模型，忽略筛网上的结构非线性特征，整张筛网看作由被底部橡胶支承条划分为k+1块的小矩形板组成。基于弹性矩形薄板振动理论，建立每小块矩形薄板的自由振动方程，提出各跨间薄板的连续性条件，利用传递矩阵方法推导出了整张筛网的传递方程，根据边界条件得到筛网自由振动的频率方程。对某一型号平板式叠层筛网的自由振动特征方程进行数值求解，得到不同螺栓预紧力、不同橡胶支撑条数目及刚度下筛网的固有频率，数据分析表明这三种参数均与筛网的固有频率呈正相关性，并且互相之间有一定影响。

Free Vibration Analysis of Shale Shaker Laminated Flat-screen

Laminated flat-screen is widely used in shale shaker, study of the influence of the structural parameters and installation parameters of the shale shaker to the free vibration of the screen can provide the basis for the design and employment of the shale shaker and screen. Elastic support multi-span continuous unidirectional rectangular plate model which is simplified by using the bolt tightening method of the screen installation model is proposed, and regardless of the structure of the nonlinear characteristics of the screen. The whole screen is divided into k+1 pieces small rectangular plates by the rubber support. Based on the elastic rectangular plate vibration theory, the free vibration equation on each piece of small rectangular plates are established, the continuity conditions of small rectangular plates between each span are put forward, the transfer function of the entire screen by using the transfer matrix method is derived, and get the free vibration frequency equation of screen according to the boundary conditions. Numerical solution for free vibration characteristic equation is conducted on a version of flat-screen to obtain the natural frequency with different magnitude of bolt preload and different numbers and stiffness of rubber support bar. Date analysis shows that these three parameters are positively correlated with the natural frequency of the screen, and have effects on each other.