The design and manufacture of plastic molds will be clo […]
The design and manufacture of plastic molds will be closely related to the process of plastic processing. The success or failure of plastic processing depends largely on the effect of mold design and the quality of mold manufacturing, and the design of plastic crate mould is based on the correct design of plastic products.
The structural elements to be considered in the design of plastic molds are
①Parting surface, that is, the contact surface where the die and the punch cooperate with each other when the die is closed. The selection of its position and form is affected by factors such as product shape and appearance, wall thickness, molding method, post-processing technology, mold type and structure, demoulding method and molding machine structure.
② Structural parts, that is, the sliders, inclined tops, straight top blocks, etc. of complex molds. The design of structural parts is very critical, which is related to the life of the mold, processing cycle, cost, product quality, etc. Therefore, designing a complex mold core structure requires a higher comprehensive ability of the designer, and pursues simpler, more durable and more economical as far as possible.
③Mould accuracy, that is, avoiding jams, precise positioning, guide posts, positioning pins, etc. The positioning system is related to the appearance quality of the product, the quality and life of the mold. According to the different structure of the mold, different positioning methods are selected. The positioning accuracy control mainly depends on the processing. The internal mold positioning is mainly considered by the designer to design a more reasonable and easy-to-adjust positioning.
The gating system, that is, the feeding channel from the injection molding machine nozzle to the cavity, includes the main channel, the runner, the gate and the cold material cavity. In particular, the selection of the gate position should help the molten plastic to fill the cavity in a good flow state, and the solid runner and gate cold material attached to the product can be easily ejected from the mold and removed when the mold is opened.
Plastic shrinkage and various factors that affect the dimensional accuracy of products, such as mold manufacturing and assembly errors, mold wear, etc. In addition, when designing compression molds and injection molds, the matching of process and structural parameters of the molding machine should also be considered. Computer-aided design technology has been widely used in moulds for pail design.