Extrusion blow molding: a plastic tube blank (parison) […]
Extrusion blow molding: a plastic tube blank (parison) in an extruded semi-molten state is placed in a mold of various shapes, and is immediately inflated by introducing compressed air into the tube blank. It is formed close to the cavity wall and is cooled and demolded to obtain a thermoforming process of the hollow part. Its entire molding process can be divided into three stages: parison formation, parison inflation, and cooling and solidification.
Extrusion blow molding is the same as other plastic hollow molding. Its main advantage is that the product is low in cost, simple in process and high in efficiency. However, its outstanding disadvantage is that the wall thickness and uniformity of the product are not easy to control.