The Reformation For Control System Of Shouqin Heat Treatment Quench

With the expansion of heavy plate heat treatment product specification and the development of the new process, how to improve the control ability and adaptability of the heat treatment furnace automatic control system becomes the hot and difficult point for the steel enterprise. Combine with production activities of the heat treatment line in Shouqin Company, this paper focus on the improving design work for the automatic control system of heat treatment line.At the first part of this paper, we research on the control principles of the original control system, fix the technical parameters and analyze the function of the controlled equipment, and refine the PLC program structure. These make the foundation for next step of the improving design work.After optimizing procedure of the hardening machine, the correction speed of water flow at high pressure zone has been faster, the time of water spray has been shorten to40s. The fast cutting valve will work as soon as the steel plate reaches the preset position, so that the pressure of water tower will be relieved, which lays a good foundation for subsequent quenching plate experiment.At the last part, we research on the bad shape and the fluctuations of the final cooling temperature during Normalizing+weak water-cooling process. We solve the problems by adding closed-loop of flow control in low pressure section of the quench. And we activate the closed-loop of the valve position control and the flow control by sequence control program of weak water-cooling. These improving designs could control the flow proportion accurately in weak water-cooling process. So the good shape and the final cooling temperature can be controlled.The optimizing design of the thick plate and Normalizing+weak water-cooling plate in this paper is based on the original equipment and control system. It’s the secondary development. The equipment and the automatic control system configuration in Shouqin company heat treatment line are used commonly in home and abroad. And compare with equipment upgrades, these two improving designs are easy to achieve the target of saving money. So this paper has high practical value in control system improvement of the heavy plate heat treatment line.