Based On The S7-400PLC Automatic System Design And Realization About Color Coating Production Line

With the rapid development of the national economy, automative industry andpower industry, the demands for color coated steel are growing up, which greatlypromoted the development of color coated steel production. Color coating productionline automatic control system which is of high efficiency, high precision and highstability, has become a trend and important factors of the industry development.Domestic and foreign large Steel Corp are all very concerned about the degree ofautomation and control precision of the color coating production line, in order to improvethe production efficiency and product quality.The control system of color coating production line is a large-scale modernizationautomatic system, which consists of uncoiler, coiler and looper controling. The controlaccuracy and automation level directly determines the product quality and productionefficiency. Compared with the developed countries, there is still a big gap in technologyof China’s current color coating production line. There also exists many defects in thecoil diameter calculation, coiler dynamic compensation and loop stability etc.In this paper the study is according to a new control system for a color coatingproduction line. A detailed analysis of the automatic control system of color coatingprocess has been made. This paper focuses on the main function and key technology ofcontrol system for this line, and on this basis, the overall design scheme and algorithmbased on S7-400PLC is proposed.This paper focuses on the design for communication and network architecture ofSiemens S7-400PLC and6RA80. It introduces the control algorithm and implementationmethod in all aspects of the system in detail. The algorithm has been optimized in theuncoiler and coiler diameter calculation, coiler dynamic torque compensation and sagcontrol algorithms. It solves some key problems, for example, automatic calculation ofdiameter deviation is too large and the torque compensation accuracy is not high incontrol system. In the end of this paper the summary has been made, and the next workof the subject has been put forward.