Research On Width Adjustable Speed Model Based On NS-VWM Online High-speed Width Adjustable Mold

As the connecting link in the production line in steel industry, continuous casting deserves our special focus since it is the core of implementing the strategies of structural readjustments and technology updates in the steel industry in China. Mold is the equipment for molding the billet, and is seen as the heart of the continuous casting machine. In order to avoid the defects of the billet like breaking out, deformation, and crack, the study on the performance of mold is important, because it can help to improve the production capacity of continuous casting and raise the quality of the billet.Currently, the width adjustment technology of mold has pointed to the direction of high speed. The high-speed width adjustment NS-VWM system developed by Nippon Steel Company in Japan has fully achieved the goal of automatic width adjustment with high speed. Different from the traditional width adjustment system, this technology enables the simultaneous processing of tap changes and parallel moves of the narrow side. It adapts to continuous casting for billets of different batches, sizes, and types. In addition, it can enhance the yield of billets, shorten the time for width adjustment and reduce the waste caused by width adjustment. Setting the width adjustment productive parameters of mold is one of the key technologies of NS-VWM system, and the speed of width adjustment is the most important parameter. Its value is decisive for the security and reliability of the online width adjustment system.This thesis takes NS-VWM mold as the main study object. It mainly studies the important parameter, the speed of width adjustment for the narrow side through field investigation, data mining, and searching for related literatures. At the same time, simulate the speed mold by MATLAB software. Firstly, the process of width adjustment is analyzed and a mechanism model is developed. Secondly, a mathematical model for the speed of width adjustment for the narrow side is established by using multiple linear regressions. Finally, to avoid the defects of particle swarm optimization algorithm such as local optimum, premature and so on. particle swarm algorithm is improved and a new GAPSO algorithm is developed through nonlinearly decreasing the inertia factors and combining operators of selection, crossover, and mutation in genetic algorithm. The BP neutral network is trained by GAPSO algorithm. It is shown in the MATLAB simulation results that GAPSO-BP network has small training error and checking error and can improve the abilities of learning and generalization to some extent. An online high-speed width adjustment model for NS-VWM mold is designed based on the neutral network.Studies on the model of the width adjustment speed for NS-VWM mold is of great engineering significance. By studying and analyzing the technology of width adjustment, the mechanism model of high-speed width adjustment system, the mathematical model for the speed of the width adjustment, and the neutral network are established in the thesis. It lays a theoretical foundation for further study and improvement of mold.