The Study Of High Performance Co-Rotating Twin-Screw Extruder And Devolatilization Mechanism

During the past few years, the co-rotating twin-screw extruder has achieved great development. Its throughput, torque and screw speed has been increased to a higher lever, and its application has been extended. The co-rotating twin-screw extruders made in our country are middle or small size machines, whose diameters are from 25mm to 100mm. The large-scale twin-screw extruders are all imported. The performance of most homemade extruders is low, and applications are narrow. The study of twin-screw extruding mechanism in China has just started, and the research on devolatilization theory is still blank. There are a lot of technical difficulties in twin-screw design, calculation and manufacture to be overcome. All these problems hamper the development of twin-screw extruding technology and devices of our country. So based on "National Nine-Five Plan" subject— the development of high performance, multifunction twin-screw extruder, we studied some technical difficulties and emphasized on research of devolatilization theory for co-rotating twin-screw extruder.Aimed at the level of the international 6^th generation co-rotating twin-screw extruder, featured in high efficiency, strong mixing & plasticating capacity, fine stability, multifunction and low consumption, we successfully developed the first homemade high performance, multifunction φ 30 co-rotating twin-screw pelletizing line. In many areas, such as high torque, high screw speed twin-screw gearbox, high viscosity gear metering pump, series thrust bearings design, manufacture and laser testing technology, we have gained great breakthrough. We consummated the geometry-modeling program of heart part of twin screw extruder—the screw element, and realized its 3D parametric design. The graphic precision and compute speed has been remarkably improved. The applicability and operability of the program have been also enhanced. All these establish valuable foundation for localization of large-scale co-rotating twin-screw extruder and development of a series of multifunction co-rotating twin-screw extruders.Based on the analysis of references about polymer devolatilization mechanism and all kinds of screw extruders' devolatilization theory and experiments, the devolatilization mechanism of co-rotating twin-screw extruder was deeply studied. By...