The processing technology of wood-plastic composite materials is different, and the difference is also very large. Nowadays, there are not many that can be applied to wood-plastic composite materials equipment, and now only single screw extruder and twin screw extruder.

Single screw extruder is usually used to complete the material conveying and plasticizing tasks. However, the traditional single-screw extruder requires special design of the screw to make it have strong raw material transportation and mixing and plasticizing capabilities, so as to complete the mixing and granulating process of the materials before extrusion.

Twin-screw extruders rely on the principle of positive displacement to transport and process materials, and can directly process wood flour or plant fibers. Wood flour drying and molten resin processes can be performed separately. Compared with the "compound" type equipment, the cone-shaped twin-screw extruder has a larger diameter of the feeding section of the cone-shaped screw, which can continuously compress the material and shorten the residence time of the material in the barrel. Small, small shear on molten materials, which is a big advantage for processing thermoplastic wood-plastic materials, so it is called "profile" type equipment with low speed and low energy consumption.

In addition, the extruder head and cooling system are also important components related to the quality of extruded products. In addition to ensuring the smooth transition and reasonable flow distribution of the flow channel design, the design of the head also needs to focus on the pressure build-up capability and temperature control accuracy of the head, and the heating and cooling device of the head should be reasonably arranged to make its cooling speed Fast and high precision, to achieve the purpose of ensuring product quality and output.

No matter what processing method we use, for wood-plastic products, the role of the mold can not be ignored. Due to the thermal sensitivity of wood-plastic materials, wood-plastic molds generally adopt a larger structural size to increase the heat capacity, so that the temperature stability of the entire head is strengthened; and the size along the extrusion direction is taken to a smaller value to shorten the material in the head In the residence time.

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