EXTRUSION OF HIGH HOOP STRENGTH HDPE TUBE BY SELF-REINFORCEMENT AND THE STUDY OF THE STRUCTURE AND PROPERTIES OF THE SAMPLE

This article introduced a new extrusion method to produce HDPE pipes w ith greatly increased hoop strength, The schematic structure and theor y of this extrusion system were discussed. Appropriate melt pressure a nd temperature fields, in conjunction with rotating mandrel permit the production of PE pipes with high hoop strength and modulus, The morph ology of reinforced products has been studied by WAXD, SEM and DSC, Th e reinforcement is due to the shish-kebab structure, which is responsi ble for the improvement of thermal and mechanical properties, The infl uence of processing parameter such as melt pressure and speed of mandr el on the strength and modulus of hoop and axis directions has also be en investigated, The hoop strength increased with increasing melt pres sure and rotating speed of mandrel.