Take you to understand the production process of wood plastic products1. PE plastic wood is currently the world's largest type of plastic wood. First, let's understand the raw materials of PE plastic wood products. The main raw materials are PE plastic, poplar powder, toner, anti-ultraviolet absorber, compatible Agent.
1. PE plastic: comprehensive comparison of cost and integrated HDPE is the best choice, and the plastic wood in the market basically uses recycled materials as the main raw material, which reduces white pollution and makes our environment more healthy and environmentally friendly. "Recycled material" is also called recycled plastic material. All plastics that can be recycled in the industry are plastics that can be reused through a certain processing process. Recycled material is divided into many grades, such as special grade recycled material and first grade recycled material. , Secondary recycling, tertiary recycling and even garbage, it is easy to understand the meaning literally, the higher the level of plastic, the less the impurity content, the garbage is naturally a high impurity content, plastic wood directly affects the choice of raw materials The quality is because the plastic wood material is a state where the wood powder is wrapped after the plastic is fused. If the impurity content of the plastic is high and the proportion of the plastic itself is small, it cannot naturally wrap the wood powder very well.
2. Wood powder: In order to achieve the perfect integration of wood powder and plastic in plastic wood, not only strict requirements for plastic, but also wood powder: the finer the wood powder of the same weight, the larger the powder surface area, when the plastic wood is fused The higher the proportion of plastic required; on the contrary, the coarser the wood powder is, the smaller the surface area of the powder is, and the lower the proportion of plastic required when plastics are fused. The wood powder selected after many years of experiment is the best poplar powder. The particle size of the powder is 80-100 mesh. The powder is too fine, the processing cost is high, the plastic component requirements are more, and the cost is higher, but The plasticity of the molded plastic wood product is too high; if the powder is too rough, the processing cost is low, and the plastic composition requirements are less, but the molded plastic wood product is not sufficiently fused, brittle, and easy to crack.
3. Auxiliary materials: The main function of the toner is to match the color of the plastic wood material. At present, the main application of the PE plastic wood is the inorganic toner. The outdoor fade resistance is better, which is different from the organic color of the PVC ecological wood used indoors. Powder, organic toner color matching is more vivid and bright. The main function of the anti-ultraviolet absorber is to improve the anti-ultraviolet capability of the plastic wood when it is used outdoors and improve the anti-aging performance. Compatibilizer is an additive that promotes the compatibility of wood flour and resin.
Plastic wood granulation workshop
Second, a simple understanding of the plastic wood raw materials, the next step is to granulate, according to the above raw materials mixed according to a certain ratio, through high temperature fusion and drying extruded plastic wood pellets, bagged for use. The main function of the granulation equipment is to achieve the pre-plasticization process of wood powder and plastic. The biomass powder material and PE plastic are uniformly mixed under melting conditions to pre-treat the production of plastic wood material. Due to the poor fluidity of the WPC melt, the design of the WPC pelletizer and the plastic pelletizer are not exactly the same. For different plastics, the design of the granulator is also different. The granulator usually used for polyethylene usually uses a conical twin-screw extruder, because polyethylene is a heat-sensitive resin, the conical twin-screw extruder has a strong shear force, and the screw length is relatively parallel The twin screw extruder is short, reducing the residence time of the material in the barrel. The outer diameter of the screw is tapered from large to small, so the compression ratio is quite large, which can make the material plasticized more fully and uniformly in the barrel.
Plastic wood extrusion workshop
3. After granulation, it enters the extrusion stage. Before the extrusion begins, a few preparations are required:
1. Make sure that there are no impurities in the hopper or the remaining pellets of other colors in order to avoid the impure color of the plastic wood produced;
2. Check whether the vacuum equipment of the extruder is smooth, and ensure that the vacuum degree is not less than -0.08mpa. The vacuum barrel should be cleaned twice per shift. Do not use metal tools to clean the exhaust holes, use plastic or wooden sticks to clean the impurities in the exhaust holes of the barrel;
3. Check whether the hopper is equipped with a metal filter, and the particulate material is processed by metal filtration to remove the metal impurities mixed in the particulate material, reducing the wear of metal impurities on the inside of the equipment and ensuring the perfect integration of the formed plastic wood profiles.
4. Whether the cooling water system is operating normally, a perfect cooling water system is necessary for the cooling of the plastic wood after extrusion, and timely cooling treatment can ensure the good shape of the plastic wood profile.
5. Install plastic-wood molds, and install the specified molds according to the required profiles.
6. Check whether the pneumatic cutting machine and other screw components can operate normally.
Plastic wood vacuum feeding machine
Plastic wood extrusion mould
4. The temperature of the newly extruded plastic-wood profile is high, and it needs to be manually placed on the flat ground, and then processed and packaged after the profile is completely cooled. Although this step is simple, it is very important. If the factory ignores these details, the factory materials will often have defects. The uneven plastic wood is easy to cause the thickness of the upper and lower surfaces of the product after the later grinding process. In addition, the uneven profile will bring certain difficulties to the construction and affect the landscape effect.
Plastic wood profiles neatly placed
Fifth, according to the needs of customers, processing plastic wood profiles:
Plastic wood processing workshop
1. Grinding treatment is to remove a layer of plastic skin produced when extruding WPC profiles, so that the WPC profiles have better wear resistance during factory installation.
Plastic wood polishing
2. Embossing treatment, after the profile surface is polished, the profile is embossed to the plastic wood, so that the surface of the plastic wood profile has the effect of imitation wood grain.
Plastic-wood pressed pattern processing
3. Cutting and tenoning processing, according to customer's customized size, tenoning and other customized products.
Tenon processing of plastic wood profiles
4. After completing the above processing, the final step is to package the product. Reasonable packaging products can reduce the damage caused by the product during shipping.