Twin-screw Extruder With Good Heat Transfer And Large Melting Capacity

In a single-screw extruder, there is frictional drag in the solid delivery section and viscous drag in the melt delivery section. The friction properties of solid materials and the viscosity of molten materials determine the conveying behavior. If some materials have poor friction properties, it will be difficult to feed the materials into the single-screw extruder if the feeding problem is not solved. In twin-screw extruders, especially intermeshing twin-screw extruders, the transmission of materials is to some extent forward displacement transmission, and the degree of forward displacement depends on the relationship between the flight of one screw and the other. The relative proximity of the screw groove. The screw geometry of closely intermeshing counter-rotating extruders results in a high degree of positive displacement conveying characteristics.
At present, the flow velocity distribution of the material in the single-screw extruder has been described quite clearly, but the flow velocity distribution of the material in the twin-screw extruder is quite complicated and difficult to describe. Many researchers just analyze the flow velocity field of the material without considering the material flow in the meshing zone, but these analysis results are quite different from the actual situation. Because the mixing characteristics and overall behavior of a twin-screw extruder mainly depend on the leakage flow that occurs in the meshing zone, however, the flow situation in the meshing zone is quite complicated. The complex flow spectrum of the material in the twin-screw extruder shows macroscopically the advantages that the single-screw extruder cannot match, such as sufficient mixing, good heat transfer, large melting capacity, strong exhaust capacity and good temperature control of the material, etc. .