Rotationally Molded Plastics
Rotationally molded plastics are one-piece, hollow parts made of plastic. Through the rotational molding process, several pieces can be molded together as one, eliminating assembly costs. Many types of plastic products can be made using the rotational molding process, including bottles, kayaks, hot tubs, trash bins, and helmets.
Several different types of plastics can be used to make rotationally molded plastics, although most are made of polyethylene. Other plastics used during the rotational molding process include nylon, Polyvinyl chloride (PVC), and polypropylene. If desired, chemicals can also be added to the plastic material in order to make the molded part resistant to corrosion, static, or flame.
From start to finish, the rotational molding takes anywhere from 15 to 90 minutes and includes four different stages. Stage one is the charging phase, which involves loading and sealing the plastic resin into metal molds. In stage two, the mold is heated on revolving axes and spindles. Stage three is the cooling stage, which is usually done with aid of a fan. During the last stage, stage four, the mold is opened and the plastic part is removed.