{1} [The position of mold in the processing industry]
   A mold is a tool that uses its specific shape to form an article having a certain shape and size. Various molds are widely used in various material processing industries. For example, various types of molds such as a sand type or a die-casting mold used for metal casting, a forging die used for metal press working, and a cold press die.
   The overall requirement for the mold is to produce a publicly-made product that meets the requirements for use in terms of dimensional accuracy, appearance, and physical properties. From the perspective of the use of the mold, high efficiency and simple operation are required; from the perspective of mold manufacturing, the structure is reasonable, the manufacturing is easy, and the cost is low.
   The mold affects the quality of the product. First, the shape and size of the mold cavity, the surface finish, the parting surface, the position of the gate and the venting groove, and the demolding method, etc., the dimensional accuracy and shape accuracy of the part, as well as the physical properties, mechanical properties, and electrical properties of the part. Performance, internal stress, isotropic, appearance quality, surface finish, bubbles, dents, burnt, silver streaks, etc. all have important effects. Secondly, during the processing, the mold structure has a great influence on the degree of difficulty in operation. When mass-produced plastic products, the process of mold opening, mold clamping and manual labor in the process of taking the parts should be minimized. For this reason, the automatic opening and closing mode automatic ejection mechanism is often adopted, and it is also guaranteed in fully automatic production. The product can automatically fall off the mold. In addition, the mold also has an impact on the cost of the product. When the batch size is not large, the cost of the mold will be large in the cost of the part. At this time, a reasonable and simple mold should be used as much as possible to reduce the cost.
   In modern production, reasonable processing technology, efficient equipment, and advanced molds play an important role in realizing the requirements of material processing technology, the use requirements of plastic parts and design.
    [2] [The development trend of molds]
   In recent years, molds have grown rapidly, and high-efficiency, automated, large, micro, precision, and long-life molds have become more and more important in the overall mold output. From the perspective of mold design and manufacturing, the development trend of molds can be divided into the following aspects:
   (1) Deepening theoretical research
   In the mold design, the research on the principle of the process is more and more in-depth. The mold design has gradually developed into the theoretical design of the theoretical design stage, which has greatly improved the output and quality of the product.
   (2) High efficiency, automation
   A large number of high-efficiency, automated mold structures are used. High-speed automated molding machines combined with advanced molds have played a significant role in improving product quality, increasing productivity and reducing costs.
   Large, ultra-small and high-precision Due to the expansion of product applications, various large, precise and long-life molding dies have emerged. In order to meet these requirements, various high strength, high hardness, high wear resistance and easy processing have been developed. A molding material with small heat treatment deformation and excellent thermal conductivity.
   (4) Standardization
       Standardization work not only greatly improves the efficiency of production molds, but also improves quality and reduces costs.
   [3] [The role of design in learning mold manufacturing]
    Through the study of the mold professional, master the technical requirements of the common materials in the various molding processes, the structural characteristics of various molds and the design calculation methods, in order to achieve the requirements of independent design of the general mold. In the mold manufacturing, master the knowledge of general machining, the selection and heat treatment of metal materials, understand the characteristics of the mold structure, and select the new process of mold processing according to different situations.
       Pouring system design
    The common gating system consists of a main flow channel, a runner, a gate, and a cold well. Before designing the casting system, the molding position of the plastic part must be determined. Only one cavity and two cavity can be used. The design of the casting system is an important part of the injection molding design. It has the injection molding cycle and the quality of the plastic parts (such as appearance, physical properties, Dimensional accuracy) has a direct impact, the design must be based on the following principles:
   (1) The cavity arrangement and the gate opening position are symmetrical to prevent the mold from being subjected to eccentric load and causing flashing.
   (2) The arrangement of the cavity and gate should be as small as possible to reduce the size of the mold. ,
   (3) The system flow path should be as short as possible, and the section size should be appropriate (too small for pressure and heat loss, too large for plastic consumption): minimize bending and low surface roughness to minimize heat and pressure loss May be small. ,
   (4) For multi-cavity, the plastic melt should enter the depth and corner of each cavity at the same time as possible, and the shunt should be arranged as balanced as possible.
   (5) Under the premise of filling the cavity, the volume of the pouring system should be as small as possible to reduce the consumption of plastic.
   (6) The position of the gate should be appropriate, and the impact insert and the small core should be avoided as much as possible to prevent the residue of the core deformation gate from affecting the appearance of the plastic part.