Do you know the difference between single screw extrusion and double screw extrusion?

A: Material delivery method-In a single-screw extruder, the solid transfer section is a friction drag and the melt transfer section is a viscous drag. If some of the material friction performance is poor, it is more difficult to feed the material. In twin-screw extruders, however, the material is conveyed to some extent in a positive displacement, and the extent of positive displacement depends on the proximity of the rib of one screw to the opposing groove of another screw. Closely intermeshing the rotation of the screw extruder geometry to get a high degree of positive displacement transport characteristics.
B: Material flow velocity field -At present, the distribution of the flow velocity of the material in the single-screw extruder has been described quite clearly. However, the flow velocity distribution of the material in the twin-screw extruder is rather complicated and difficult to describe. The complex flow spectrum of the material in the twin-screw extruder shows macroscopically the unparalleled advantages of a single-screw extruder, such as good mixing, good heat transfer, large melting capacity, strong exhaust capacity and good material temperature control .