(3) Other plastic injection processes. We provide the production and processing of first-class plastic bags and the wholesale of plastic bags throughout the country. 11. Sealing and pressing to the human type will melt material injection into the open mold, in the injection of melt before curing through external force for the second time, so as to make the product performance is changed. The method can reduce the molecular orientation caused by injection and improve the optical properties of the product, so it can be widely used in dry dense optical industry.
2. The decorative film in the injection mold will be heated and vacuum preformed. Then the inner surface is injected into 'L3, so that the decorative film and the slave body are integrated into a product. This method avoids V secondary processing of surface decoration of general plastic brake products.
3. The gas trapping type uses high-pressure gas to inject into the melt. Make the final side parts into a hollow state. Gas-assisted injection into I method has the following advantages: first, ding to reduce the internal stress of the product. Thus reducing wing flexion and deformation; Second, the clamping force can be reduced. Thus reducing equipment costs; Three is to improve the surface of the products sold; Four is to save materials. Shorten the molding cycle; Fifth, enhance structural characteristics. Larger and more complex products can be produced. The process of gas-assisted injection into M consists of five parts.
(1) Injection period. Volt injection part melt is generally 50% to 80% of the cavity,
(2) Inflation period. A silent gas (usually nitrogen) must be injected at a pressure greater than the melt pressure (2.5 to 30MI'a). Make the product hollow.
(3) Gas pressure holding period. After the inside of the product is filled with gas, the gas pressure acts as the holding pressure. To compensate for melt shrinkage. Reduce deformation.
(4) gas recovery and discharge a. With the completion of the cooling cycle of the recovered gas "about 70% of the gas can be collected), so that the gas pressure in the product is reduced to atmospheric pressure.
(5) touch. Finished mountain mold cavity top out.
The large-scale production of plastic bags has already been realized.
Blow molding is one of the important processing methods of hot leisure materials, which can be used to process hollow products such as film and bottle, poke and so on. The blowing molding equipment is simple. The bottle body can be square, round or flat, suitable for PE,PP,PVC,PC,PLT and other thermoplastic lamas 1.
(1) Technological process
According to the different process, blowing molding can be divided into extrusion blow molding and injection blow molding. Extrusion blow molding process by extruder resin fusion plasticizing extruded v shape blank. Then put the blank in the blow molding mold, blow with compressed air, after cooling finalize the mold with the same shape of the poke or bottle body. The process of injection molding and blow molding is to inject the molten material into the machine to form a needle shape. Then open the ju blank to stay on the core touch, while hot blow molding mold and blow air to make the blank blown into the mold cavity shape. Cooling demoulding ready products. Extrusion blow molding for a variety of plastics, can produce large products, mainly barrels; Uniform wall thickness during injection molding and blowing. Suitable for the production of large number of sites, small precision products. The production process of blow molding bottle is shown in Figure 1-8, and the production process of injection blow molding bottle is shown in Figure I-9. Plastic bags are our main products, which are sold to a wide range of plastic bag markets throughout the country.