The increasing demands on automotive plastic parts and the speed at which automotive moulds are being developed at ever lower costs are forcing manufacturers of automotive plastic parts to develop and adopt new production processes. Injection moulding is the most important technology for the production of plastic automotive parts.
Due to the unique characteristics of complex plastic parts for automobiles, the design of injection moulds for automotive parts needs to take into account the following factors: drying of the material, new requirements for glass fibre reinforcement, drive forms and mould clamping structures.
Firstly, when the resin material commonly used for car bumpers and instrument panels is a modified resin (e.g. modified PP and modified ABS), the resin material has different moisture absorption properties. The resin material must be dried or dehumidified with hot air before it enters the screw preform of the injection moulding machine.
Secondly, domestic plastic parts currently used in automobiles are essentially non-glass fibre reinforced plastic products. The materials and construction of injection moulding machine screws used to mould non-glass fibre reinforced plastic parts are very different compared to the use of chopped glass fibre reinforced resins. When injection moulding automotive plastics, attention should be paid to the alloy material of the screw and the special heat treatment process to ensure its corrosion resistance and strength.
Thirdly, because automotive parts are different from conventional products, they have very complex cavity surfaces, uneven stresses and uneven stress distribution. The design needs to take into account the processing capacity. The processing capacity of the injection moulding machine is reflected in the clamping force and injection capacity. When the injection moulding machine is forming the product, the clamping force must be greater than the injection pressure, otherwise the mould surface will hold up and create burrs.
Proper mould clamping needs to be taken into account and the injection pressure must be less than the rated clamping force of the injection moulding machine. The maximum capacity of the injection moulding machine is matched to the tonnage of the injection moulding machine.
Post time: Nov-10-2022
