Mon May 29 23:05:47 CST 2023
All kinds of tools and products used in our daily production and life, from the base of machine tools and machine shells to a small embryonic head screw, button and the shell of various household appliances, all have a close relationship with the mold. The shape of the mold determines the shape of these products, and the processing quality and precision of the mold also determines the quality of these products. Because of the different materials, appearance, specifications and usage of various products, the moulds are divided into casting moulds, forging moulds, die-casting moulds, stamping moulds and other non-plastic moulds, as well as plastic moulds.
Mold design and manufacturing are closely related to plastic processing. The success or failure of plastic processing depends largely on the effect of mold design and mold manufacturing quality, and plastic mold design is based on the correct design of plastic products.
Plastic mold design to consider the structural elements are:
① parting surface, i.e. the contact surface where the concave mold and convex mold fit each other when the mold is closed. Its location and form are influenced by the shape and appearance of the product, wall thickness, molding method, post-processing process, mold type and structure, mold release method and molding machine structure.
②Structural parts, i.e. slider, slant top, straight top block of complex molds, etc. The design of the structural parts is very critical, which is related to the life of the mold, processing cycle, cost, product quality, etc. Therefore, the design of the core structure of complex molds requires high comprehensive ability of the designer, pursuing simpler, more durable and more economical design solutions as much as possible.
③ Mold accuracy, i.e. card avoidance, fine positioning, guide pillar, positioning pin, etc. Positioning system is related to product appearance quality, mold quality and life, according to different mold structure, choose different positioning methods, positioning accuracy control mainly relies on processing, internal mold positioning is mainly the designer to fully consider, design a more reasonable and easy to adjust the positioning method.
②Pouring system, that is, from the injection molding machine nozzle to the cavity between the feed channel, including the main flow channel, diversion channel, gate and cold cavity. In particular, the location of the gate should be selected to facilitate the molten plastic in a good flow state filled cavity, attached to the product of the solid runner and gate cold material is easy to eject from the mold and be removed when the mold is opened (except for hot runner mold).
③ plastic shrinkage rate and the factors affecting the dimensional accuracy of the product, such as mold manufacturing and assembly errors, mold wear and tear, etc.. In addition, the design of compression and injection molds, should also consider the molding machine process and structural parameters of the match. Computer-aided design technology has been widely used in the design of plastic molds