Generally speaking, there are two main forming processes of pulp molding machine: vacuum forming and slip casting.
Vacuum molding of pulp molding machine
Vacuum molding of pulp molding machine is the most popular method for making paper pulp products. It has rotary, turnover and reciprocating according to different structures of pulp molding machine.
Rotary type pulp molding machine features: continuous rotating production, high production efficiency, large mold investment, high mold processing accuracy, high equipment processing accuracy technical requirements, one set of concave molds with eight sets of punches, and CNC center processing molds are required. The processing cycle is long and the investment is large. Because it is continuous production, it is suitable for mass production of stereotyped products, such as egg trays, dinner trays, wine trays, and egg cartons. For industrial molding production, it is not applicable due to non-standard, small quantity, small batch, and large mold investment.
Turnover pulp molding machine features: Turnover production is less efficient than rotary pulp molding machine, suitable for medium batch and non-standard production of industrial molding, but because it is a set of concave molds with two sets of punches, it needs to be processed by a CNC center mold, mold investment is large, and the cycle is long.
Features of reciprocating pulp molding machine: The production efficiency is lower than that of the drum type, and it is not much different from the turnover type. Because the equipment only needs a set of concave molds to match a set of punches, it does not need CNC center processing, which is especially suitable for non-standard and batches, small, fast-cycle industrial packaging products.
Slip casting of pulp molding machine
According to different pulp packaging products, the slip casting molding method calculates the required amount of pulp (material) and quantitatively injects it into the molding cavity for adsorption molding. This kind of molding method is suitable for standard products with little changes and finalized shapes. It is commonly used in tableware molded products. Since the finalizing calculation is difficult to grasp, this molding method is not used in non-standard paper-plastic packaging (industrial packaging).