Similar to the single-screw extrusion process, twin-screw extrusion process can be divided into feeding and solid conveying, melting and melt delivery of three stages.But the work of twin-screw extruder and single screw extruder is completely different.On the one hand , Twin-screw extruder for the positive transport, forced to push the material forward.On the other hand, twin-screw extruder in the two screw meshing at the material to produce a strong shear effect, increase the mixing and plasticizing effect .

For example, when the screw rotates in the same direction, the helix of one screw extends like a wedge into the screw of the other screw, the material can not be continued into the adjacent groove by the groove, but can only be Forced by a screw saw groove to another screw screw groove to the material in the two screw repeatedly forced between the steering, by a good shear mixing effect.If the screw is the reverse rotation, The material must go through the mouth, the material seems to roll through the two nips, so the shear effect will be better.