Parallel twin-screw extruders are widely used in the filling, blending, modification, reinforcement of rubber and engineering resins, as well as the devolatilization treatment of chlorinated polypropylene and high water absorbent resins; Extrusion of biodegradable masterbatch, polyamide condensation polymerization, and polyurethane addition reaction; Preparation of carbon powder, magnetic powder granulation, insulation materials for cables, sheath materials, low smoke and low halogen flame retardant PVC cable materials, and various silane crosslinking materials. Small models are mainly used for scientific research and teaching.