1 Introduction 

    The various tools and products used in our daily production and life are as large as the base of the machine tool, the shell of the machine body, and the size of a single head screw, button, and shell of various household appliances, all of which are closely related to the mold. The shape of the mold determines the shape of these products. The quality and accuracy of the mold determines the quality of these products. Because of the different materials, appearances, specifications, and uses of various products, molds are divided into non-plastic molds such as casting molds, forging molds, die-casting molds, stamping molds, and plastic molds.

    In recent years, with the rapid development of the plastics industry and the continuous improvement in the strength and accuracy of general-purpose and engineering plastics, the application range of plastic products is also expanding, such as: household appliances, instrumentation, construction equipment, automotive industry, and In areas such as hardware, the proportion of plastic products is increasing rapidly. A well-designed plastic part can often replace many traditional metal parts. The trend toward the plasticization of industrial products and household products continues to rise.

    2, the general definition of the mold: In industrial production, using a variety of presses and special tools installed on the press, through the pressure of metal or non-metallic materials to produce the desired shape of the parts or products, this special tool is collectively referred to as the mold .

    3, injection molding process description: mold is a tool for the production of plastic products. It consists of several sets of parts, which have molding cavities inside. During injection molding, the mold is clamped on the injection molding machine. The molten plastic is injected into the mold cavity, and is cooled and set in the cavity. Then the upper and lower molds are separated, the product is ejected from the mold cavity through the ejector system, and finally the mold is closed again. For the next injection molding, the entire injection molding process is performed cyclically.

    4, the general classification of mold: can be divided into plastic mold and non-plastic mold:

    (1) Non-plastic molds include: casting molds, forging molds, stamping molds, and die casting molds.

    A. Casting mold - faucet, pig iron platform

    B. Forging die - car body

    C. Stamping die - computer panel

    D. Die casting mold - super alloy, cylinder block

    (2) Plastic molds are divided into:

    A. Injection Molding - TV Case, Keyboard Buttons (Applications Most Common)

    B. Blowing mold - beverage bottle

    C. Compression Mold - Bakelite Switch, Scientific Porcelain Dishes

    D. Transfer Molding - Integrated Circuit Products

    E. Extrusion molds - glue pipes, plastic bags

    F. Thermoforming molds - transparent molded packaging shell

    G. Rotary Molding - Soft Rubber Doll Toy

    ◆ Injection molding is the most commonly used method in plastic processing. This method is applicable to all thermoplastic plastics and partially thermoset plastics. The large number of plastic products obtained is beyond the reach of other molding methods. As one of the main tools for injection molding processing, the injection molds are used in mass accuracy, manufacturing cycle and injection molding process. The level of production efficiency in China and other countries directly affects the quality, output, cost, and product renewal of products, and at the same time determines the responsiveness and speed of enterprises in market competition.

    ◆ Injection mold is composed of several pieces of steel plate and various parts, basically divided into:

    A forming device (die, punch)

    B positioning device (guide post, guide sleeve)