Temperature Control And Implementation Of Spraying And Drying Production Line Based On PLC

In the field of of industrial control of the Sheet metal production lines, the technology of relay control can be considered as a traditional method. The main control function can be achieved by using the physical relay. For the larger control system, a large number of relays are required to use, and the reliability is poor. Once there exsits the fault, it is very difficult to diagnose and remove the fault. Recovery time is very long. Meanwhile, we can find that the function of relay cntrol is single, and inflexible, and it is not easy to modify.Programmable Logic Controller (PLC) is a specialized equipment in industrial production process, because it can meet the requirement of equipment use environment and the reliability of control, it is used in the modern industry control system heavily, very broad of prospects. Spraying process is an important part of sheet metal processing technology, it is level of automation and control accuracy decides of the sheet metal pieces in the process of surface treatment quality for good or bad. From two aspects of hardware and software design of temperature control system of drying.The main work of this paper is as follows:Firstly, we introduced the domestic and foreign coating production line of research, and point out the present problems. By combining with the production line work demanded in recently years, we propose coating production line control system design method based on the programmable controller (PLC).Secondly, we discuss the basic principle of PLC, and analysze the function and characteristics of PLC. Meanwhile, we elaborate the PLC for spraying production line control significance. Thirdly, the temperature control of the drying system is a critical parameter. For the characteristics of the drying room spray painting temperature control, we investigate the problem of drying room spray painting temperature control. By using the Siemens S7-200series of PLC control system, a spray painting temperature control design method based on PLC is proposed. Finally, simulation results show that PLC control is more reliable and simpler on process flow than the relay control system.Fourthly, consider the power drying control system as an example, and we analyze the technological requirements and the parts working state analysis of parts. Furthermore, we make power drying temperature control.Finally, the results of the thesis are summarized and further research topics are pointed out.