Design And Research Of The Control System Of Polypropylene Extrusion Granulation

Polypropylene is one of the widely used polymer materials in industry and extrusion granulation is one of key steps in the process. In recent years, the scale of Polypropylene Industry has been rapidly increasing and its potential market is still large. However, the manufacture of the extruder and the development of its control system are just beginning in China.This paper has introduced the Polypropylene Industry around the world and the development of the control industry, deeply studied the process of extrusion granulation. Based on the principle of reliability and feasibility, a series of suitable hardware equipments have been chosen and a whole package of control system was developed through the Siemens PCS7platform to meet control requirements for barrel temperature, screw speed, safety interlock, start and stop of the main motor.In the extrusion process, barrel temperature and melt pressure are key variables which affect the quality of products mostly. In this paper, strategies of barrel temperature control with a large time delay are being studied and simulated on the platform of MATLAB, which provides a final conclusion, and a CFC configuration loop is established through the PCS7.