The development of plastics and plastics industry
The use of plastic parts in industry is becoming more and more common because of its special advantages. The plastic density is small and the quality is light. Plastic is higher than strength; Good insulation performance, low dielectric loss, is an indispensable raw material for electronic industry; The chemical stability of plastics is high, and it has good corrosion resistance to acid, alkali and many chemicals. Plastic also has good anti-friction, wear-resisting and shock absorber, sound insulation performance is also better. Therefore, plastic is among the three traditional materials of metal, fiber and silicate. In the national economy, plastic making has become one of the indispensable materials for all industries. Plastic industrial development stage is roughly divided into stages: 1. The start-up stage before the 30 s, scientists aldehyde, nitric acid fiber and polyamide hot plastic, such as their industrialization is characterized by the intermittent method, small batch production. 2. Industrialization of low-density polyethylene, PVC and other plastics was developed in the 1930s, laying the foundation for the plastics industry and opening the way for further development. 3. From the mid-1950s to the end of the 1960s, the production and quantity of plastics increased and the forming technology became more perfect. 4. The stable growth phase, since the 70 s by copolymerization, crosslinking, blending, composite, enhance, foaming and filling method to improve the plastic performance, improve product quality and expand the application field, production technology more hasten is reasonable. The plastics industry is developing towards automation, continuum, product serialization, and new areas that do not broaden functionality and plastics. The development of plastics industry in China is late. The late '50 s, due to the production of equipment of polyvinyl chloride, and the mid - 70 - the introduction of petrochemical installations completed and put into operation, make the plastic industry has two leaps, at the same time, plastic processing machinery and technology method also got rapid development, all kinds of processing technology has been complete. Because of its continuous development and application, and the continuous development of molding process, plastic has greatly promoted the development of moulds. Work with industrial plastic parts and a variety of daily-use plastic parts and the demand is increasing, and the upgrading of products cycle is becoming more and more short, the plastic and yield and quality put forward higher and higher requirements
The important role of plastic molding in industrial production
Mold is an important process equipment in industrial production, and mold industry is one of the important foundations of the development of national economy. Plastic mold is a mould used for forming plastic parts. It is a type of cavity mold. The stand or fall of the level of mold design, processing equipment, manufacturing strength, on the strength of the mold quality, directly affects the development of many new products and upgrading of old products, affect the product quality and to increase the economic benefit. The American industry believes that "the mold industry is the foundation of American industry", while Japan says "mould is the labor force to promote prosperity and prosperity". In recent years, various industries in China have attached great importance to the development of mold. In 1989, the state council issued "the key points of industrial policy decision", in the key support transformation of industry, product, mold manufacturing as mechanical technical transformation sequence of the first, it determines the important position of the mold industry in the national economy, and also puts forward the main task of the revitalization of the mould industry.
The development trend of plastic molding technology
A good pair of plastic mould and mould design, mould materials and mould manufacturing has a lot to do. Plastic molding technology trends can be simply classified into several aspects: 1. The standardization of mold in order to adapt to the large-scale batch production of plastic molding and shorten the tooling manufacturing cycle of needs, the mould standardization work is very important, at present, the standardization degree of only 20%. Injection mold parts, mold die set and other technical conditions and standard has 14 standard: research task is to focus on the current development boom flow standard components and mould temperature control device; Precision standard mould frame, precision guide series; Standard templates and mold standard parts of advanced technology and the standardized module, etc. (2) to strengthen theoretical research (3) the plastic parts of motors, miniaturization and ultra large 4. New material, new technology, new technology research, development and application of various new materials development and application of mould processing technology innovation, the application of CAD/CAM/CAE technology is the development trend of mould design and manufacturing.
Classification of plastic mold
There are many methods for classification of plastic mold. According to the molding method of plastic parts, the following categories can be divided into the following categories: 1. Injection mould (also called injection mold); 2. Compression mode; 3. Pressure injection mold; Extrusion die; 5. Pneumatic forming die. The above is the common forming method, and the foam plastic molding mold, the mold, the casting mould, the rotary mold, the polytetrafluoroethylene - thin mold, etc.