Blow molding is a manufacturing process by which hollow plastic parts are formed.
In extrusion blow-molding plastic is melted and extruded into a hollow tube (a parison). Closing it into a cooled metal mold the parison is captured and formed. The air is then blown into the parison, inflating it into the shape of the hollow bottle, container or part.
After the plastic has cooled sufficiently, the mold is opened and the part is ejected. In Continuous Extrusion Blow Molding the parison is extruded continuously and the individual parts are cut off by the mold.