昆山达亮塑胶模具有限公司

1. Analyze the structure and technical requirements of plastic parts. The structure of the plastic part determines the complexity of the injection mold structure, and the technical requirements of the plastic part (dimensional accuracy, surface roughness, etc.) determine the difficulty of the injection mold manufacturing and molding process. Therefore, for the special requirements that do not meet the plastic injection molding, unreasonable structure shape, etc., the improvement design scheme of the injection mold should be proposed, otherwise the injection mold design will be increased Considering the difficulty of manufacturing and injection molding process.

2. Familiar with technical specifications of injection molding machine. The technical specifications of injection molding machine restrict the size of injection mold and the range of injection products that can be molded.

3. Understand the processing and processing properties of plastics. Including the flow position of the plastic melt, the larger flow distance ratio that the melt can reach: analyze the flow resistance of the runner and the mold cavity, the exhaust of the original air in the mold cavity, the possible crystallization, orientation and the internal stress caused by the plastic in the injection mold, the cooling shrinkage and compensation of the plastic, the requirements of the plastic on the temperature of the injection mold, etc.

4. Considering the design and manufacture of injection mold, the following problems are mainly solved.

a. The structure of injection mold should be selected reasonably. According to the drawings and technical requirements of plastic parts, research and select appropriate molding methods and equipment, combine with the mechanical processing capacity of the factory, put forward the structural scheme of injection mold, fully solicit the opinions of relevant parties, conduct analysis and discussion, so as to design the injection mold with reasonable structure, reliable quality and convenient operation. If necessary, the requirements for modifying the drawings of plastic parts can be put forward according to the needs of injection mold design and processing, but can be implemented only with the consent of the user.

b. The dimension of injection molding parts shall be calculated correctly. Forming parts are the direct factors to determine the shape, size and surface quality of plastic parts, which have a great relationship and need special attention. The average shrinkage method can be used to calculate the size of formed parts. For plastic parts with high precision and need to control the trimming allowance, the tolerance zone method can be used for calculation. For large precision plastic parts, the analogy method can be used as much as possible to measure the shrinkage rate of plastic parts in different directions, so as to make up for some factors that are difficult to be considered in theory.

c. The designed injection mold shall be easy to manufacture. When designing the injection mold, try to make the designed injection mold easy to manufacture and low in cost. Especially for those complex forming parts, we must consider whether to use general machining method or special machining method. If a special processing method is adopted, then how to assemble after processing, similar problems should be considered and solved in the design of injection mold, and at the same time, the mold repair after trial mold should be considered, and enough mold repair allowance should be reserved.

d. The injection mould should be designed with high efficiency, safety and reliability. This requirement involves many aspects of the injection mold design, such as the pouring system needs to be filled, closed modules, the effect of temperature regulating Xirong is good, and the demoulding mechanism is flexible and reliable.

e. Injection mold parts shall be wear-resistant and durable. The durability of injection mold parts affects the service life of the whole injection mold. Therefore, when designing this kind of parts, we should not only put forward necessary requirements for their materials, processing methods, heat treatment, etc., but also pin components such as push rods are easy to be stuck, bent, broken, so the resulting failures account for the majority of injection mold failures. Therefore, it is necessary to consider how to adjust and replace conveniently, but it is necessary to note that the service life of the parts is suitable for the injection mold.

f. The structure of injection mold should adapt to the molding characteristics of plastics. In the design of injection mold, we should fully understand the molding characteristics of the plastic used and try to meet the requirements, which is also an important measure to obtain high-quality plastic parts.