Understanding of the design and manufacture of plastic mold

Plastic industry is a high polymer chemical department of producing synthetic resin and plastic products, but also to industrial manufacture of plastic processing machinery and mold included. Plastic industrial production and varieties, production and development mainly depends on the synthetic resin, so the relationship and petrochemical close Plastic with its light weight, high strength, corrosion resistance, high production efficiency, low energy consumption characteristics in some areas, machinery manufacturing, building departments, can replace the metal and wood; in electronics, electrical appliances and other departments, has become one of the essential materials of plastic; plastic products widely used in agricultural production and people's life.; in packaging, it can be said that the current no plastic, almost no packaging industry plastic industrial modernization is a material industry develops very fast, the 1946 world plastic yield only 600kt, 1970 has reached 30.4Mt. In 1984 reached 72Mt, accounting for three of synthetic materials (plastics, synthetic rubber, synthetic fiber) 5% of the total output, concentrated production areas are in Western Europe (35%), North America (30%), Asia (17%), Eastern Europe (13%. 70 years later, the new situation of plastic industry is: ① synthetic resin device to realize the large scale, continuous and automatic production line, single reached more than 120kt. High efficiency catalyst and process is simplified, and the energy saving bulk polymerization method realized industrialization. In the varieties, linear low density polyethylene asked and large-scale production is the outstanding representative. The engineering plastics, composite materials and high performance materials development is very rapid, there have been many new varieties, such as liquid crystal self reinforced plastic started mass production. Engineering plastics growth rate has exceeded the general plastics, such as in the 70's, the development speed of engineering plastics for an average annual growth of 15%, more than twice as high as in many general-purpose plastics. The 1984 world engineering plastics consumption growth rate is 14%, the total consumption of 1.383Mt. The plastic processing to energy conservation, conservation of raw materials as the goal, plastic machinery more and more high level of automation; the new method processing emerge. For example: reaction formation, structural foam injection molding and injection molding of thermosetting plastic (see injection molding); CO extrusion technology, CO extrusion film, sheet and profile (see extrusion); multi-layer blow molding, extrusion blow molding and injection stretch blow molding (see blow); Reinforced Plastic Pultruded etc.. The world plastic annual per capita consumption of 1970 8kg1980 13.4kg, in 1995 is expected to reach 22.5kg, industrial developed countries more than 50kg.