Explanation

It is a two-step molding method for producing hollow plastics containers. The injection machine injects molten plastics into the parison mold under high pressure to form a tubular parison. After the mold is opened, the parison remains on the core mold (also known as the mandrel). The hot parison is moved into the blow mold through a mechanical device. After the mold is closed, 0.2-0.7MPa compressed air is introduced from the core mold channel to make the parison expand to the shape of the blow mold cavity. The parison is cooled and shaped under air pressure, and the product is obtained after demoulding. Compared with the extrusion blow molding method, the advantages of the injection blow molding method are: high product accuracy, uniform wall thickness, no need for post modification processing, no seam lines in the product, and less waste edge. The disadvantages are: high investment costs for molds and specialized injection molding machines, limited shape and size of production containers, and unsuitable for producing containers with handles. It is mainly used for packaging cosmetics, daily necessities, medicine and food. The commonly used resin are PP, PE, PS, SAN, PVC, PC, etc.

Classification