The design and manufacture of preform molds is a complex engineering process integrating materials science, fluid mechanics, and precision machining. Its value lies in precisely controlling the wall thickness distribution, neck structure, and overall shape of the preform, laying the foundation for subsequent blow molding processes. Modern preform molds utilize integrated CAD/CAM design, combined with finite element analysis (FEA) technology, to simulate the flow of molten plastic within the mold cavity, optimizing gate location and cooling system layout. This eliminates stress concentration, reduces flash, and ensures that the dimensional accuracy of each preform is consistently within ±0.05mm.
In terms of material selection, mold steels (such as S136 and H13) undergo vacuum quenching and cryogenic treatment, achieving a hardness of HRC52 or higher. This allows them to withstand the high temperature and pressure of high-speed injection molding while maintaining long-term wear resistance. Surface treatment technologies such as nitriding and PVD coating further enhance the mold's corrosion resistance and demolding performance, shortening the production cycle by more than 30%.
