Filament Extruder Triple Heater Extruder 3D Printer Filament Recycle for Makers The single-screw plastic extruder is one of the core pieces of equipment in the plastic processing field. Its primary function is to continuously extrude solid plastic raw materials (such as granules and powders) into plastic products or semi-finished products with specific cross-sectional shapes through the rotation of the screw, which involves heating, melting, kneading, and pressurizing the materials.