Blow Molding Machine

A blow molding machine manufactures hollow plastic objects, most commonly bottles and containers, by inflating a heated, softened tube or preform of plastic inside a closed mold with compressed air until it takes the shape of the mold's cavity. The American engineers Enoch Ferngren and William Kopitke, working at the Hartford Empire Company, patented an early automatic blow molding machine in the late 1930s, adapting the glass-bottle blow-and-blow forming principle to the newly available thermoplastics, and the process was subsequently commercialized by the Plax Corporation. Automated extrusion blow molding became the standard manufacturing method for plastic bottles once cheap polyethylene became widely available after the Second World War, and later injection blow molding and stretch blow molding variants extended the same inflation principle to more precisely shaped and higher-strength containers.