What is the professional definition of blow molding machine? Blow molding, also known as hollow blow molding, is a rapidly developing plastic processing method. The tubular plastic parison obtained by extrusion or injection molding of thermoplastic resin is placed in the open die while it is hot (or heated to the softening state). After the mold is closed, compressed air is injected into the parison immediately to inflate the plastic parison and cling to the inner wall of the mold. After cooling and demoulding, various hollow products are obtained. The professional definition and classification of blow molding machine are introduced as follows. The manufacturing process of blown film is very similar to blow molding of hollow products in principle, but it does not use molds. From the perspective of classification of plastic processing skills, the molding process of blown film is usually included in extrusion. Blow molding began to be used to produce LDPE vials during World War II. In the late 1950s, with the birth of HDPE and the development of blow molding machine, blow molding technology has been widely used. Some of the containers have been produced with a volume of several thousand liters. The plastics suitable for blow molding are polyethylene, polyvinyl chloride, polypropylene, polyester, etc. the hollow containers obtained are widely used as industrial packaging containers.