Research On Ball-Spinning Forming For Large Size And Thin-Walled Tube

Modern spinning,used as an advanced plastic forming technology,has been widely applied to many fields,such as Aeronautics,Astronautics and Weaponry,etc.However,in the process of manufacture,many process parameters affect the qualities of spinned parts,people have to establish process parameters by trial-and-error approach,this process can be improved by the finite element numerical simulation technology.In this paper,research is carried out by numerical simulation and experiment technology for ball spinning forming process of thin-wall tubes,its main results are as follows:(1) Based on DEFORM-3D finite element platform, finite element model of ball spinning process is established. The influence law of forming quality with process parameters such as thinning ratio, axial feeding ratio and ball working angle is analyzed,through theoretical and experimental parameters comparative analysis,there are reasonable spinning craft parameters:thinning ratio=25-30%,axial feeding ratio f=0.5-1.0mm/r,ball working angle 20°.(2) Ball spinning forming process in GH4169 large diameter(300mm)tubing has been studied,metal flow pattern of spinning process has been analyzed.Multipass spinning forming process and each lane process parameters on forming effect are simulated,the possibility of forming is discussed.The influence of the axial feeding ratio, ball diameter and thinning ratio on the large diameter tubing forming is on numerical analysis,and gain some law.(3) The theory research on calculation of the tubing ball spinning pressure is carried through,and analysis the conditions of the contact deforming force. The calculation formula of contact deforming pressure is derivated,then the physical model of theoretical calculation for the tubing ball spinning is determined.There are compared differences between the numerical simulation results and the physical model calculation results,so range of applications with the spinning force calculation model is given.(4) The design work for GZ300 models of tubing ball spinning is completed,design for main components is included of cylinder design,motor with belt transmission and the whole mold design.The main parameters for spinning machine have been determined including the longest press trip of the spinning machine,the biggest diameter of the workpiece,the maximum length of the workpiece and the maximum thickness of the workpiece.