1.To determine the gate location according to the plastic part structure and usage requirements. As long as the structure allows, the nozzle and nozzle head in the fixed mold insert does not interfere with the molding structure, and the gate of the hot runner system can be at any position of the plastic part. The position of the injection gate for conventional plastic injection molding is usually selected based on experience. For large and complex special-shaped plastic parts, the position of the injection molding feed inlet can be simulated by computer-aided analysis (CAE) to simulate the flow of molten plastic in the cavity, analyze the cooling effect of each part of the mold, and determine the ideal gate location.
2.Determining the nozzle head form of the hot runner system. Product material and use characteristics are the key factors for choosing the nozzle head form, and the production batch of plastic parts and the manufacturing cost of the mold are also important factors for choosing the nozzle head form.
3.The number of cavities per mold is determined by the production batch of the product and the tonnage of the injection machine.
4.The number of nozzles is determined by the position of the glue inlet and the number of cavities per mold. If you form a product, choose one mold and one feed inlet, you only need one nozzle, that is, use a single-head hot runner system; if you form a product, choose one mold with multiple cavities or one mold with one cavity with more than two feeds If you want to open the nozzle, you need multiple nozzles, that is, a multi-head hot runner system is used, except for the mold structure with a cross runner.
5.To decide the radial size of the nozzle accords to the weight of the plastic part and the number of nozzles. At present, the nozzles of the same form have multiple size series, which meet the requirements of forming plastic parts in different weight ranges.
6.Deciding the mold structure size according to the plastic part structure, then select the nozzle standard-length series size according to the thickness of the fixed mold insert and the fixed template, and finally trim the thickness of the fixed template and other dimensions related to the hot runner system.
7.Confirming the shape of the hot runner fixing plate according to the shape of the hot runner plate, arrange the power cord lead groove on the plate, and design an adequate cooling water loop near the hot runner plate, nozzles, and nozzle heads.