Blow molding: Also known as hollow blow molding, a rapidly developing plastic processing method. The tubular plastic billet obtained by extrusion or injection molding of thermoplastic resin is placed in a split mold while it is hot (or heated to a softened state), and compressed air is passed into the billet immediately after the mold is closed, so that the plastic billet is blown and close to the inner wall of the mold, and various hollow products are obtained after cooling and demoulding. The manufacturing process of blow molded film is very similar in principle to that of blow molded hollow products, but it does not use molds, and the molding process of blow molded film is usually included in the extrusion from the perspective of plastic processing technology classification.
The tubular plastic billet obtained by extrusion or injection molding of thermoplastic resin is placed in a split mold while it is hot (or heated to a softened state), and compressed air is passed into the billet immediately after the mold is closed, so that the plastic billet is blown and close to the inner wall of the mold, and various hollow products are obtained after cooling and demoulding. The manufacturing process of blow molded film is very similar in principle to that of blow molded hollow products, but it does not use molds, and the molding process of blow molded film is usually included in the extrusion from the perspective of plastic processing technology classification. The blow molding process began to be used to produce low density polyethylene vials during World War II. In the late 1950s, with the birth of high-density polyethylene and the development of blow molding machines, blow molding technology has been widely used. The volume of hollow containers can reach thousands of liters, and some production has been controlled by computers. The plastics suitable for blow molding are polyethylene, polyvinyl chloride, polypropylene, polyester, etc., and the resulting empty containers are widely used as industrial packaging containers.