Many applications call for specialized extrusion processes to obtain adequate results or speed up the production process. Common specialty extrusion processes include:
Blown film extrusion: Used to fabricate plastic film products such as grocery and food storage bags The dies in this process feature an upright, cylindrical design that pulls the molten plastic upward as it forms and cools.
Coextrusion: Several layers of material are extruded at the same time. Two or more extruders feed different types of plastic into a single extrusion head.
Overjacketing: Extrusion is employed to coat an item in protective plastic coating. Exterior wire and cable jacketing is the most common application of overjacketing.
Tubing extrusion: Similar to traditional extrusion, except the die includes interior pins or mandrels to facilitate the production of hollow plastic materials.