Injection Mold Design And Manufacturing Requirements And Precautions

Injection mold design and manufacturing requirements and precautions

The injection mold factory must fully understand the characteristics of the processed plastic raw materials when designing the injection mold, so that the designed injection mold is used rationally, and the characteristics of the plastic are effectively used in the design process. Therefore, the issues that need to be considered in the injection mold design process are as follows:

1. In-depth analysis of the structure of plastic parts and its technical requirements. The structure of the plastic part determines the complexity of the injection mold structure. The technical requirements of the plastic part (dimensional accuracy, surface roughness, etc.) determine the difficulty of the injection mold manufacturing and molding process, so there is no special requirement for plastic injection molding. , Unreasonable structural shapes, etc., should be proposed to improve the design of injection molded parts, otherwise it will increase the difficulty of injection mold design and manufacturing and injection molding process.

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

3. Understand the processing performance and process performance of plastics. Including the flow position of the plastic melt, the larger the flow distance ratio that the melt can achieve: analysis of the flow resistance of the runner and the cavity, the original air discharge in the mold cavity, and the possible occurrence of plastic in the injection mold Crystallization, orientation and the internal stress caused by it, plastic cooling shrinkage and compensation problems, plastics' requirements for injection mold temperature, etc.

Considering the design and manufacturing of injection molds, the following problems should be solved.

1. The structure of the injection mold should be selected reasonably. According to the drawings and technical requirements of plastic parts, research and select appropriate molding methods and equipment, combined with the machining capabilities of the factory, propose an injection mold structure plan, fully solicit opinions from relevant parties, conduct analysis and discussion, in order to design the injection mold structure Reasonable, reliable in quality and easy to operate. When necessary, according to the needs of injection mold design and processing, the requirements for modifying the drawings of the plastic parts can be proposed, but it can be implemented after obtaining the user's consent.

2. The dimensions of injection moulded parts should be calculated correctly. Molded parts are the direct factors that determine the shape, size and surface quality of plastic parts, which are closely related and require special attention. When calculating the size of molded parts, generally the average shrinkage method can be used. For plastic parts with high accuracy and need to control the mold repair margin, it can be calculated according to the tolerance zone method. For large precision plastic parts, try to use the analogy method to calculate the shrinkage rate of the measured plastic part geometry in different directions. Make up for the influence of certain factors that are difficult to consider in theory.