In this paper

polyethylene (PE) pipes with three diameters were prepared via die rotation extrusion and a thorough research was done on their microstructures and properties. The experimental results showed that compared to shish-kebab parallel to axial direction of PE pipe prepared by convention extrusion

hoop drag flow caused by die rotation was superimposed on axial traction flow during die rotation extrusion and the polymer flow direction was off the axial direction of the pipe so that the direction of shish-kebab alignment deviated from the axial direction to increase hoop orientation of the PE pipe and improve significantly the hoop strength and suppress the crack growth along the axial direction. With the increasing diameter of the PE pipe

hoop linear velocity went up at the same angular velocity and the angles of shish kebab deviated from the axial direction became larger so more improvement was achieved in the PE pipe with the longer diameter.