Dynamics Modeling And Simulation Analysis For Vertical Vibration System Of Four Rollers Rolling Mill

Many factors affect the vertical vibration of four rollers rolling mill,in order to research thecharacteristics of vertical vibration and inherent characteristics，considering the influence of variousfactors on vertical vibration of rolling mill,a variety of vertical vibration system dynamics modelsare established from different angles, and the finite element model is established too.The researchcontent of this paper is as follows:（1）Using the simplified model,,the six freedom dynamic vertical vibration system of fourroller rolling mill model is established, using Matlab software to calculate the natural frequencies ofthe dynamical model and the corresponding main vibration mode, and then analyse the naturalfrequency and main vibration mode；Considering the nonlinear stiffness and nonlinear damping inthe vertical vibration system of the rolling mill,a two degrees of freedom nonlinear dynamic modeland a four degrees of freedom nonlinear dynamic model with considering nonlinear stiffness andnonlinear damping are established,then get the corresponding dynamics differentialequation.Selecting the two degrees of freedom nonlinear dynamic differential equation,usingMATLAB software to simulate and analyse it, Geting the amplitude frequency characteristic curvesof primary resonance and non resonance.By analysing the curves of primary resonance and nonresonance,the dynamic characteristics of vertical vibration with nonlinear factors is known；Considering the lag elastic-plastic deformation in the rolling process with rolling nonlinear,a millrolling system dynamics model of hysteresis nonlinear is bulit,and get the nonlinear hystereticdynamics equation；Considering the elastic constraints,a nonlinear dynamic model of the verticalvibration system with considering the elastic constraints is built,and get the nonlinear dynamicequation,then simulate and ansylse nonlinear dynamic equation by the MATLAB software,and getthe amplitude frequency characteristic curves of vertical vibration system of rolling mill mainresonance of nonlinear dynamics model and non main resonance,by analysing the curves of primaryresonance and non resonance,the dynamic characteristics of vertical vibration with nonlinear factorsis known.（2）Based on the above models and solving simulation,using the software of Solid-works toestablish the frame and the roller system model,then analyse the stress by the SimulationXpressstress analysis module,and get the deformation strain distribution of the frame in two typicalvibration frequencies.Establishing the finite element model of rolling process,and usingANSYS/LS-DYNA software to analyse the finite element model of rolling process,I can get the stress distribution nephogram drawing of the rolling process model.Finally, according to the stressdistribution and strain distribution of roll system of rolling process model,the stress and strain ofwork roll and backup roll are analyzed,obtain the stress and strain distribution correspondingly bymeans of the finite element method.（3）According to the test results of four rollers mill in a certain factory,the vertical vibrationsignalof four rollers rolling mill is obtained by experimental testing.Using the work rollers in a700ms period of vertical vibration displacement curve,then the displacement of the verticalvibration of working rollers finite element simulation drawing into the same coordinatesystem.Based on test data are compared with the simulation data, to verify the validity of simulationmodel and simulation results.