The design of pulp molded products actually includes the structural design and processing mold design of pulp mold itself, which are interdependent and related. Usually, the design between the two needs to be completed synchronously. There are three general design steps and key points:
(1)First design the product structure, and then design the mold according to the product structure. This is because the product is used to protect and fix the product, so its internal dimensions should match the overall dimensions of the product.
(2) In mold design, first design the integral mold, and then design the molding mold. In the later stage of production, the shaping process has higher requirements for size control, so it is necessary to ensure size control in the shaping process. This requires that the size of the shaping mold be designed first, and the thickness of pulp molded products should be fully considered. At the same time, it is also necessary to take into account the demoulding problem after the integration, and a certain size of gap needs to be reserved for demoulding. Moreover, the molding process will further pressurize the formed products, especially in thickness, so the molding die is redesigned based on the size of the molding die. Generally, the characteristics of the forming mould and process will be considered in terms of size, such as the thickness of the net covering wire of the forming mould, the size shrinkage after integral heating, etc.
(3) In mold design, the lower mold should be designed first, and then the upper mold. Generally, the molding lower mold is designed based on the size of the integral upper mold, and the molding upper mold is made by molding the lower mold with epoxy resin. Moreover, the matching problem between the external dimensions of pulp molded products and the internal dimensions of cartons makes it more advantageous to design the lower die first.