Modeling And Simulation For Vertical Vibration System Of Four Rollers Cold Rolling Mill Based On The Dynamic Roll Gap

The vertical vibration phenomena of four rollers strip cold rolling mill is studied as the researchobject, causes and main influencing factors of the vertical vibration are discussed and researched inthis thesis. Modeling and simulation analysis for vertical vibration system and rolling process ofrolling mill are performed on the basis of structural modal analysis and dynamic response theory. Themain contents of this paper are as follows:(1)The dynamic roll gap mechanical model is established in consideration of the verticalvibration of rolling mill rollers and the effect brought by elastic-plastic deformation rule of rolledmetal. On the basis of this model, the formulas of dynamic rolling force and variation amount forrolling force in the dynamic roll gap are deduced fully considering the disturbance brought by verticalvibration in the actual rolling process. For further study the impact of rolled metal deformation ratebrought by the vertical vibration displacement of rolls, the formulas of rolled metal deformation rateis deduced, which will enrich the content of study in dynamic roll gap models of four rollers coldrolling mill.(2)The dynamic modal analysis for work roll, backup roll and mill frame of four rollers coldrolling mill is made by using software ANSYS on the basis of the model established by using softwareSolidWorks. Research on the effect of the roll gap deformation is made, brought from the work roll,the backup roll, mill frame and their own inherent vibration modal including their deformation in thevertical direction. Some models of the various rolling mill components in specific vibrationfrequencies which affect the roll gap deformation greater has been studied in detail. The strength andthe deformation of mill frame are checked in the static analysis before its dynamic modal analysis inconsideration of the complex work environment of mill frame.(3)In order to study the influence for stability of rolling mill brought from the parameters of theroll gap, dynamic simulation analysis of rolling process is made for different roll gap frictioncoefficient, different rolling speed and different entrance thickness of rolled metal by using thenonlinear software ANSYS/LS-DYNA to obtain the distribution of equivalent stress and strain ofrolling mill system under different roll gap friction coefficient, different rolling speed and differententrance thickness of rolled metal and to understand the specific influence on the stability of rollingmill brought from these parameters.(4)The vertical vibration test of2800four-roller reversible cold rolling mill in a domesticenterprise is made and the six degrees of freedom vibration model of rolling mill system is established.The nature of rolling mill vibration and vibration factors have been researched and explored in depthcombining processing and analysis of the vibration signal with computing research of themathematical model. Diagnosing vibration source of the vertical vibration by testing methods and identifying the main vibration frequency of the work roll by combining the established mathematicalmodels. The test results influenced by various parameters are compared and analyzed for furtheranalysis and study of the impact for vertical vibration of rolling mill brought from various parametersin the rolling process, and the conclusions of dynamic simulation for the rolling process based onvarious parameters of the roll gap are verified.