| With the development of machining and manufacturing industry, the requirements of steel become higher. The market demand for the quality of the plate and strip products is increasing, and the impact of the board shape and the crown control on the quality of the products is becoming prominent increasingly. Plate shape and plate crown are important indexes to measure the quality of steel products. This paper calculated hot-rolling metal plastic deformation and rolling elastic deformation model. The hot-rolling finish rolling schedule is developed and the new curve of work roll shape has been designed and tested in the industry.First, the temperature drop is calculated, the force of total rolling is estimated, and front tension and back tension stress transverse distribution is obtained. On the base of rolling contact surface pressure distribution differential equation, the distribution model of rolling pressure is developed with the stress analysis of the workpiece deformation zone micro unit. By using the method of piecewise discrete method, the rolling and deformation are discretized, and the differential equation is established. Then the pressure distribution is obtained. The above two models are the basic model of the analysis of the principle of shape control. Hot rolling metal plastic deformation model directly reveals the hot rolling process of workpiece deformation the essence of law; rolling elastic deformation calculation model calculates the deformation of work rolling and gap shape.We establish the rolling schedule of hot strip mill. In the hot strip rolling production, reasonable rolling process can maintain a good steel shape. Rolling schedule setting can be regarded as a control method for the control of the shape of the hot strip mill. The key parameters, such as deformation resistance, temperature, rolling force, rolling torque, motor power, etc., are calculated. The finishing rolling schedule for 850 hot rolling production line of Jinxi Steel is optimized. In this paper, the finish rolling optimization of rolling schedule numerical optimization is designed. The optimized design method is reliable for the optimization of the plate thickness and the plate crown.Then, the quality of the products of 850 hot rolling line of Jin Xi Steel has been investigated. It is found that the roll cooling is not ideal, the temperature is not uniform. On the basis of the above, the suggestions for improving the cooling water and optimizing the rolling rhythm are put forward. In order to find cooling water and the rolling rhythm’s influence on a hot rolling, the measured data of 850 hot strip mill is analysised and influence diagrams are made by the data. The results show that the cooling water and rolling rhythm significantly affected the strip shape. On the basis of the actual working conditions of 850 hot rolling production, the work rolling shape curve is designed and the parameter values are optimized. Considering the limitation of the work rolling grinder, the curve of the rolling type and the optimum parameters of the roller are given.Finally, in order to determine the designed curve of the work roll effects, we made the rolling test. Different thickness of the plate of Q235 and Q195 were selected. At 850 hot rolling mill line the results data of rolling test was collected. The results show that the new designed rolling curve can effectively improve the flatness and profile. According to the 850 hot strip mill production line condition, some matters needing attention in production are put forward. |
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