PP PPR PE PVC pipe extruder are available as single screw extruders and twin-screw extruders. The appropriate extruder will generally be selected according to the specific material.

The material transport of single screw extruders is mainly by friction, which leads to a limited dosing performance, with powders, pastes, glass fibers and inorganic fillers being more difficult to incorporate. Furthermore, single-screw extruders do not melt and plasticize as well as twin-screw extruders, but they are less costly compared to twin-screw extruders. Twin-screw extruders have a wider range of applications and higher output and efficiency compared to single-screw extruders.

Currently, polyethylene (PE) and polypropylene (PP) pellets are generally produced using single-screw extruders. Rather than the traditional three-stage, fully threaded screw, most screws incorporate a mixing element to improve mixing and plasticization.

The raw material for PVC is in powder form and must be mixed and pelletized beforehand if produced using a single-screw extruder, which complicates the production process. For this reason, a conical twin-screw extruder is now generally chosen directly for the mixing and forming of PVC powder.