Forming theory of co-rotating parallel twin-screw extruder

Co-rotating parallel twin-screw extruder When the screws rotate in the same direction, the teeth of one screw protrude into the screw groove of the other screw like a wedge, and the material cannot continue to enter the adjacent screw groove from the screw groove. It can only be forced to flow from the saw groove of one screw to the screw groove of another screw. In this way, the material is repeatedly forced to turn between the two screws, and has received a good shear mixing effect. If the screw rotates in the opposite direction, the material must pass through the jaws, and the material seems to pass through the nip between the two rollers, so the shearing effect will be better.

Similar to the single-screw extrusion process, the twin-screw extrusion process can also be divided into three stages: feeding and solid conveying, melting and melt conveying. But the working principle of twin-screw extruder is completely different from that of single-screw extruder. On the one hand, the twin-screw extruder is forward conveying, forcing the material to move forward. On the other hand, the twin-screw extruder has a strong shearing effect on the material at the meshing of the two screws, which increases the mixing and plasticizing effect of the material.