Extrusion is the process of melting plastic inside a heated barrel with a rotating screw and forcing the melt through a shaped opening called a die. It is the heart of both plastic recycling and plastic product manufacturing.
In a recycling line, washed flakes or agglomerate are fed into the extruder, melted, degassed to remove moisture and volatiles, and pushed through fine screens that filter out remaining contamination. The clean melt is then cut into granules in the pelletizing step. The same principle makes finished products: blown film, pipes, sheets and raffia tapes are all extruded.
