Blow molding (also called blow molding) is a manufacturing process by which hollow plastic parts are formed, such as plastic bottles and pipes. Say no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get the original essay Materials Blow molded parts can be made from a variety of thermoplastic materials, including the following: Polyethylene (low and high density) Polyethylene terephthalate (PET)Polypropylene (PP)Polyvinyl chloride (PVC)Blow molding processThe plastic is heated until it melts and becomes a viscous fluid. Then this plastic is extruded through a blow mold to form a tube shape called a Parison. A mold containing a cavity is closed around a parison before pressurized air is blown inside so that the parison expands against a wall of the cavity. A plastic is cooled and hardened and the air is released. Then the mold opens and the part is made.Types of Blow MoldingThere are three types of blow molding:Extrusion-blowInjection-blow moldingStretch-blowExtrusion-blowThe plastic is melted and extruded into a hollow parison before being closed in a cold metal mold. Then air is introduced into a parison, making it a hollow bottle, can, glass or coin by pushing it against a wall of the cavity. the pieces are cut by a knife. Intermittent Extrusion Molding In this type of extruder screw works, then stops for a while and the molten plastic is driven out. Now the accumulator is used to collect the melted plastic. Injection blow molding It is used for manufacturing hollow objects in large quantities. The stages of injection molding are Injection Blow Ejection Injection The polymer is melted and it is then transferred to a heated preform mold where the preform is formed. It is a temporarily shaped product used to make a final product. BlowingThe preform is then passed into the refrigerated hollow mold. Then, through the central rod, air is blown into a performance material around which the mold is clamped. Ejection The final product is cooled and then removed from the blow mold and central rod. Stretch Blow Molding In this process, the plastic is made into a preform by using the injection molding process. These parts are then transferred to a machine where they are heated beyond the glass transition temperature using heaters or infrared heaters. The air is then blown at high pressure using metal blow molds. The central rod is now used to pull the preform. This method is used to make bottles and other things.Advantages of Blow MoldingKeep in mind: This is just a sample.Get a custom paper now from our expert writers.Get a custom essayIt is corelessRapid cooling is carried out during blow moldingComplex hollow shape products can be manufacturedHigh production rateLow tooling and die costFlash recycling can be carried outDisadvantages of blow moldingIt is only used for hollow partsHollow parts thick cannot be formedCutting is requiredLow strength