The Design And Analysis Of The Novel Screw Extruder Of Coextrusion In One Extruder

Coextrusion is a process that moulds the multilayer product in one die by two or more than two extruders. It has been more and more widely used in many fields because of its simple manufacture process and the excellent characteristics of its product. There are some problems in existing equipment, such as the high investment, the complex structure, the waste of energy, "weld lines" of product, and so on. More and more overseas researchers pay attention to the study of the novel, efficient coextrusion technology, and they acquired achievement, A successful equipment is the nested cone extruder "Conex". Domestic research is little.In this paper, a novel concept was introduced. It is the nesting screw structure concept for the novel coextrusion technology in one extruder, which is based on the classical Tadmor melting theory without changing the common screw basic structure.The novel structure is different from the overseas equitments as it is the creationary design based on the commen single screw extruder. It is the first time that coextrusion in one extruder domestic.Some projects from the concept were introduced and compared ,one of them was chosen for the practice design. The extrusion system ,the transmission system and the coextrusion die of the novel screw extruder were designed and simulated. By the finite element analysis software ANSYS, the stress and transmutation analysis of screw and shaft were done. The dimension was optimized. The flow channel of the die was simulated by PLOYFLOW and the optimized rotate speed of the inener and outer screws was got. The analysis will conduct and help the research of experiment of this extruder and the design of other correlative extrusion dies. The novel crew extruder was produced based on the design, and experimental research was done. The goals of the design were achieved and the primary analysis was proved.This paper will provide the theory and experience for the futher experimental research and design of the correlative machines in the field of coextrusion in one extruder.