The conical twin screw rotates in the extruder barrel, and the friction between the material and the two causes the working surface of the extruder screw and barrel to gradually wear: the diameter of the extruder screw is gradually reduced, and thediameter of the inner hole of the extruder barrel gradually increases. In this way, the matching diameter gap between the screw and barrel of the extruder increases a little as the two gradually wear.
However, since the resistance of the head and the manifold in front of the extruder barrel has not changed, this increases the leakage flow of the extruded material when it advances, that is, the amount of material flowing from the diameter gap to the feeding direction increases, resulting in plastic The mechanical output decreases. This phenomenon increases the residence time of the material in the extruder barrel and causes the material to decompose. In the case of polyvinyl chloride, the hydrogen chloride gas produced by decomposition strengthens the corrosion of the screw and barrel of the extruder.
The extruder screw is widely used in the filling, blending, modification, reinforcement of rubber and engineering resins, dehydration treatment of chlorinated polypropylene and super absorbent resin; degradable masterbatch, polyamide polycondensation, polyurethane polyaddition reaction Extrusion; granulation of carbon powder and magnetic powder, insulation materials for cables, sheath materials, low-smoke and low-halogen flame-retardant PVC cable materials and preparation of various silane cross-linked materials, etc. Small models are mainly used for scientific research and teaching. The structural design directly affects the normal operation of the entire machine system.
Because the gearbox of the parallel twin-screw extruder relies on the large thrust of the output shaft for rubber mixing, the center distance of the two extruder screws is relatively small, and the output structure requires high rotation accuracy, so it is difficult to design and process the product.
Our company is specialized in producing parallel and co-rotating modular screw elements, barrels and screws, involving various models from Ø20mm to Ø300mm. After ten years of vigorous development, our company now has a number of advanced CNC machine tools and special processing equipment for screw manufacturing. Now our machining operations have basically realized intelligence and automation. Advanced processing methods, strong technical force, and sophisticated processing technology ensure that the quality and technical indicators of each production fully satisfy customers. If you have any need, please consult us.