Study Of The Friction Coefficient In Roll Gap On Suppressing Vertical Vibration In Cold Rolling Mill

Modern machining technology put forward more and more highly demand to the requirement and quality of plate strip. However, in the steel rolling processes, the cold rolling mill vibration problem is a more general phenomenon. Cold rolling mill vibration is easily exacerbate destroy equipments, increase the production costs, reduce production efficiency of products, the economic benefits of Steel companies is largely restricted. Therefore, vibration research on this issue has important practical significance.The article analyzed the vibration phenomenon of F4 cold rolling mill, the vertical vibration problem of cold rolling mill was analyzed from the perspective of the roll gap friction factor. The main research includes the following aspect:(1) A simplified vertical vibration model of F4 cold rolling mill with eight degrees of freedom was established. Then the model was analyzed with the help of MATLAB and the analysis result was the natural frequencies and the main vibration modes of cold rolling mill, the frequency of vibration of the cold rolling mill was 136.50 Hz and 481.81 Hz by the result was analyzed, Belong to third octaves of vibration and fifth octaves of vibration. Then rolls, racks and assembly of cold rolling mill was analyzed with the help of ANSYS modal function. The results obtained with the same result as described above, the results proved that the simplify model and effect of cold rolling mill was right, further define the vertical vibration of this cold rolling mill was the third octave vibration and a fifth octave vibration.(2) The mechanical model of vertical vibration of cold rolling mill was established, the mechanism of third octaves of vibration and fifth octaves of vibration was elaborated. The effects was studied between the tension changes, contact arc length, reduction ratio, rolling thickness, rolling speed, friction lubrication and vertical vibration of cold rolling mill. Due to the factors mentioned above are mostly affected vertical vibration of rolling mill by changing the friction coefficient, therefore, friction factor of factors have been discussed. On this basis, the internal and external factors of influence friction coefficient of the process of rolling are summarized.(3) A model of cold rolling mill roll gap friction factor was established by BP neural network, through the production data collected in production field, the BP network friction was tested, and determines whether to meet the accuracy requirements by test data. BP neural network model has been shown to have high accuracy, the relationship between roll gap friction factor and the factors affecting can quantitative research by the neural network. Using this networking more accurate and efficient may be getting the stability of the whole process of rolling lubrication parameters, more accurate and more efficient than ever, in other words, through this network to obtain the friction factor of cold rolling mill stable operation and relevant parameters under this friction factor. By subsequent regulation, it is able to maintain the stable operation of the cold rolling mill in the rolling process.