二、CSP轧机辊系水平与垂直耦合振动研究(英文投国际会议)

Research on the Impact of the Vertical Vibration of CSP Rolling Mill Hydraulic Pressure System on the Horizontal Vibration of the Roll SystemXiaoqiang Yan 1） Miao Bao 1） Guanghong Zhu 2） Yukun Yan 2）1）University of Science and Technology Beijing Beijing 100083 Email: 2）Maanshan Iron & Steel Co, Ltd.Keywords: CSP rolling mill，Hydraulic pressure system，Vertical vibration，Horizontal vibration，Roll systemAbstract CSP rolling mill abnormal vibration problem is one of the worldwide difficult problems in rolling fields. In this article, using the morden acceleration telemetry system, an integrated test to the mill vibration is taken and the laws of the mill vibration are captured. The test shows that there is severe horizontal vibration on the mills roll system, especially the work rolls, at the same time, there are also abnormal vibration occurs on the hydraulic pressure system of the mill. In order to the reveal the internal links between the vertical vibration of the mill hydraulic pressure system and the horizontal vibration of the roll system, using the harmonic analysis module and the transient response analysis module of ANSYS software, through simulation study to search the impact of the vertical vibration of the mill hydraulic pressure system on the horizontal vibration of the roll system and meaningful conclutions are clarified.1. IntroductionSince U.S. made the worlds first set of CSP rolling mill(Compact Strip Rolling Process) manufactured by Tpco company put into operation in1989, The whole world have already had 35 sets of CSP mill production line by 2009.Since the coming out of CSP mill, there has been a severe phantom vibration which has not been thoroughly solved for two decades, and it has become a difficult problem in the rolling fields around the world.Since Zhujiang Iron and Steel Co,Ltd introduced the first set of CSP production line in 1998, 7 CSP production lines have been put into operation so far. Several CSP mills (F2-F4 stand) when rolling thin gague or products with high deformation resistance, often associated with phenomenon of strong horizontal vibration and noise, leading to the work rolls surface and strip surface generate obvious oscillation marks, which can greatly reducing the life of roll online and the quality of strip surface, and even causing accidents of strip break, steel-heaping and holding roller, threatening the safe running of the equipment. It has become a difficult problem in a number of CSP production lines in our country. Through a lot of field experiment and theory research, we have known that there are Vertical-torsional vibration1, Bending-torsional coupling vibration2 and Electro-mechanical coupling vibration phenomenon on CSP rolling mill. Its center vibration frequency is 42.75Hz. Field test shows that rolling mill also has the phenomenon of horizontal vibration on roll system, and noise generated by the vibration has a serious impact on the working environment.Reviewing the results of previous studies, Scholars of domestic and overseas divided the mill vibration into vertical vibration on mill stand and torsional vibration on mill main drive system, they have done a lot of research work on the two kinds of vibration and have made some meaningful achievements3. However, there is very little research on horizontal vibration of the mill roll system. Especially the impact of the hydraulic pressing system vertical vibration on the horizontal vibration of the mill roll system is almost a gap4. This article starts from the field test, signal analysis and simulation, solving the influence law of the coupling vibration of the rolls horizontal vibration and vertical vibration, trying to get scientific explanation of the test signals.1. Vibration Test Signals AnalysisChoosing the CSP F4 mill as a test object, we made a comprehensive test on the main parts of the mill, and find that when F4 is in abnormal vibration condition, the work rolls produce a significant horizontal vibration, The typical acceleration waveform and spectral image as shown in Fig.1, its difficult to explain this phenomenon using traditional rolling mill vibration theory, therefore, we try to obtain a scientific explanation through the use of software simulation.Fig.1 F4 work roll vibration acceleration signal and spectral image3.The Impact of the Hydraulic Pressing System Vertical Vibration on Horizontal Vibration Of The Rolling Mill SystemIn order to study the discipline of the impact of the vertical vibration of the mill hydraulic pressure system on the horizontal vibration of the roll system, using the harmonic analysis module of the ANSYS software to make simulation study. Firstly, establishing the finite element model of the mill, as is shown in Fig.2. Fig.2 CSP mill finite element model and loadingFig.3 The impact of the vertical vibration on the horizontal vibration amplitude frequency response curveTo simulate the impact of the hydraulic pressing vertical vibration on the horizontal vibration of the rolling mill system, imposed vertical vibration loads on the roll bearing of the back up rolls to simulate the impact of the horizontal vibration on the roll system. In order to study convenience, Firstly, the hydraulic pressing system vibration is simplified to a harmonic load, the size of the rolling force F is exerted according to the actual hydraulic pressure during the rolling process. (1)In Eq.1, F represents the stability of the value of the rolling force, =1100KN represents the vibration amplitude of the rolling force, the value of varies between 50-72Hz. The simulation results shows in Fig.3.From the figure, at the frequency of 56Hz and 67Hz, the horizontal vibration of the upper and the lower work rolls has a peak. And the vibration amplitude of the lower work roll is bigger than the upper work roll, the simulation results in good agreement with the tested data. .Similarly, rolling force is imposed on the roll bearing of the back up roll in the vertical direction, which is the same as the above, the frequency is only =67Hz, the displacement and acceleration response both of the upper and the lower work rolls operation side bearing box (the location of measurement points) are obtained as is shown in Figure 4- Fig.7.Fig.4 The displacement response of the Fig.5 The displacement response of theupper work roll horizontal vibration lower work roll horizontal vibrationFig.6 The acceleration response of the Fig.7 The acceleration response of theupper work roll horizontal vibration upper work roll horizontal vibrationAs can be seen from Fig.4 and Fig.5, the displacement amplitude of the horizontal vibration on the upper work roll is about 1.75E-5m, and the displacement amplitude of the horizontal vibration on the lower work roll is about 2.5E-5m, which is basically consistent with the harmonic response in Fig.3. As can be seen from Fig.6 and Fig.7, obtained by simulation, the acceleration vibration amplitude on the upper work roll is about 16m/s2, while on the lower work roll it is about 20m/s2, which is grater than that of the upper work roll vibration amplitude; while the measured acceleration of the horizontal vibration amplitude on the lower work roll is between about 1550m/s2 , typical acceleration signals are shown in Fig.1.As stated previously, the hydraulic pressing system vertical vibration has apparent impact on the horizontal vibration of the rolling mill system.4.ConclusionsStarting from the field test, signal analysis and simulation analysis to find the impact of the hydraulic pressing system vertical vibration on the horizontal vibration of the rolling mill system, the following conclusions are clarified after in-depth study:1) The test signals analysis shows that: There is a relationship between the work rolls horizontal vibration of the rolling mill system and the hydraulic pressing system, vibration frequency is 50-72Hz.2) Simulation results shows that the hydraulic pressing system vertical vibration has significant impact on the horizontal vibration of the roll system, which is often forming a very complex vibration phenomenon when it is rolling particular specification strip, and at the frequency of 56Hz and 67Hz it appeared a peak in the horiz