Study On The DCS Of Plastics Extruding Line

Automation control system is a proper extension in plastics extrusion lines. The target of automation control system is to supervise and control all of the important parameters of the whole product line. The control system of those march-past meters is always applied into the plastics extrusion line for automatically supervising and controlling. With the development of the "4C" technology, the computer control system has been used to increase stability and reliability of processing equipment in the whole plastic extrusion line.According to the points of economics and practicality, this thesis mainly discusses to resolve problems coming from production process. The first of all, it analyses the principle and technique of the plastics extrusion. Secondly, studying the ratio between capability and quotation from all kinds of electrical controllers in the distributed marks. At last, it brings forward the control ideas and project of the plastics extrusion line. Based on these two factors above, the distributed control system of the plastic extrusion line is designed and developed. This DCS makes use of S7-200 programable logic controller from Siemens, personal computer and WinCC, HMI designing software to realize centralized management, distributed control and remote supervision and controlling by Ethernet. The control system includes different ways to control the key technical parameter of three necessary parts in the product line, such as temperature control in different parts, drivers control, supplying and calculating materials control. According to the special character objects, the different control projects are put forward: the temperature control bases on the PID, the arithmetic of parameters adjustment and control rule of the solid-state relay. It thinks out a PID-Relay control arithmetic applied into the plastics extrusion line. Driver control bases on the VSD control technology,...