Study On Temperature Control Of Hot Strip Rolling Process Of GF08Al

GF08Al is a kind of hot-rolled strip steel developed by Tangshan Guofeng Iron and Steel Co,Ltd.and Northeast University.It is widely used in hardware,furniture,bicycle parts,automobile body manufacturing,aerospace,precision instruments,and household appliances industry and so on.In order to ensure the quality of GF08Al,the finishing rolling temperature must be controlled within a reasonable range.The finishing rolling temperature is controlled by adjusting the speed of rolling.However,due to the changeable product specifications,there is no rule to follow to control the speed of rolling which only can be determined by repeated rolling tests.In order to solve the problems,the finite element software DEFORM is used to simulate the roughing and finishing process in GF08Al production process.The temperature field,displacement field,stress field and deformation of the whole rolling process are obtained,and the final rolling temperature and rolling speed under different product thickness and opening temperature are obtained.The variation law between final rolling temperature and rolling speed can provide reliable guidance for field production to accurately control various process parameters such as the rolling starting temperature,rolling speed and finishing rolling temperature.The main contents of this paper are as follows:(1)Finite element model of roughing and finishing rolling process in GF08Al production process was established by DEFORM software.The rolling process of GF08Al was simulated under certain starting temperature and product thickness.The finishing rolling temperature controlled by rolling speed was obtained.The simulated finishing rolling temperature was compared with the measured finishing rolling temperature.The results show that the absolute error of the simulation temperature is within 3?,the relative error is within 0.344%,which are smaller than the required absolute error+/-10? and relative error 1.15%respectively.(2)Through orthogonal design and simulation experiment,the simulation test data of finishing rolling temperature and rolling speed under different product thickness and opening temperature were obtained.(3)A new controlling method of finishing rolling temperature by using rolling speed is proposed,and the controlling equation of finishing rolling temperature is put forward.The mathematical expression of final rolling temperature controlling equation is obtained by regression calculation of simulated data.(4)By comparing and analyzing the final rolling temperature calculated by the govern equation with the actual rolling temperature measured under the same working condition,the absolute error is less than 4,and the relative error is less than 0.471%.The results verify the accuracy of the govern equation.Finally,the temperature equation of finishing rolling is deduced further,and the formula of controlling finishing rolling temperature by speed is obtained.