Blow molding is a technology that blowing plastic into the hollow article. 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. Hollow container’s volume can be up to thousands of liters, and some have adopted computer-controlled production. For blow plastics are polyethylene, polyvinyl chloride, polypropylene, polyester, etc. The empty containers are widely used in industrial packaging. According to the production method of the parison, blow molding can be divided into extrusion blow molding and injection blow molding.