Study on Pumping Conveying Capacity Characteristics of Polymer Solids in Vane Extruder

Abstract

Abstract A vane extruder consists of a group of vane plasticization units that can together be considered a vane pump. During extrusion, materials in the extruder are plasticized and conveyed by positive conveying and suppressed by normal stress. A mathematical model of the pumping capacity of polymer solids in the vane extruder is established based on its structure and conveying mechanism. The minimum bulk density under atmospheric pressure and leakage coefficient in this model are obtained experimentally. Four general polymer materials are chosen to investigate the pumping conveying capacity of polymer solids in the vane extruder. The experimental results of the first vane plasticization unit show that the pumping conveying capacity increases almost linearly with the rotor velocity and is only slightly influenced by the material properties. Furthermore, the leakage coefficient increases when the temperature and velocity in the vane extrusion process are set inappropriately; this reduces the pumping conveying capacity of polymer solids in the vane extruder.