Research On Vibration Characteristics And Control Of Rolling Mill Rolling System Based On Vibration Absorber

With the rapid development of science and technology,the intelligent manufacturing industry has put forward higher requirements for the precision of rolling products.Therefore,the vibration phenomenon of rolling mills has gradually become the focus of attention.Due to the characteristics of the mechanical structure of the rolling mill,the vertical vibration of the rolling mill is easy to occur during the rolling process,which leads to a serious impact on the precision of the rolled product.In order to effectively restrain the vertical vibration problem of the rolling mill during the rolling process,the researchers conducted in-depth research on the vibration phenomenon of the rolling mill roller system from various aspects.Therefore,in order to effectively improve the precision of rolling products,this paper has carried out in-depth research on the vibration characteristics and control methods of rolling mill rolls with vibration absorbers.First of all,in order to effectively suppress the vertical vibration of the rolling mill system,combined with the vibration damping characteristics of the vibration absorber,the rolling mill dynamics suppression model with a mill shock absorber is constructed.Meanwhile,according to the D'Alembert's principle,the dynamic equation of the rolling mill is established.The fixed-point theory is used to design and optimize the basic parameters of the vibration absorber.The system amplitude multiplying response curves with several different frequency ratios are analyzed.The characteristic law that the characteristic amplitude response curve of the system has to pass the two fixed points is found and is used to obtain the optimal coherent frequency and optimal damping ratio of the vibration absorber.Then,based on the dynamic model and dynamic equation of the roller system of the rolling mill,the multi-scale algorithm is used to solve the main and internal resonance responses of the rolling mill main system with vibration absorber.Thus,the amplitude-frequency response equation of the main and internal resonances of the rolling mill main system with the vibration absorber is obtained.At the same time,combined with the actual test data of the 1780 four-roll mill,the time domain characteristics,spectral characteristics,amplitude-frequency characteristics and main resonance singular characteristics of the rolling mill roll system with vibration absorber are studied.These characteristic laws confirm that the mill vibration absorber can effectively suppress the vertical vibration phenomenon of the four-roll mill during the actual rolling process.Finally,the double-delay feedback control function for the vertical vibration displacement and velocity of a rolling mill with a vibration absorber is designed.It is applied to the dynamic equation of the rolling mill with the vibration absorber.The multi-scale algorithm is used to find the main and internal common amplitude frequency response equations of the controlled equation.By adjusting the gain coefficient and the magnitude of the time-delay parameter,it is possible to effectively control the amplitude-frequency characteristics of the vertical vibration of the rolling mill with the vibration absorber and the stability of the limit ring amplitude.Meanwhile,the static bifurcation behavior of the rolling mill with the vibration absorber is controlled,which improves the stability of the rolling mill main system with the vibration absorber in the actual rolling production.