Study On Rotary Swaging Process And Equipment Development Of TU2 Thin-walled Copper Tube

As an efficient heat transfer component, heat pipes have been widely used in various fields. Necking process is an important manufacturing process of the heat pipes, because it can directly affect the subsequent processes, and thus affects the heat transfer performance of heat pipes. The thesis selects TU2 thin-walled copper tube as the research object, and theoretical analysis, numerical simulation and experimental test as research methods, to study rotary swaging forming process of copper tube and the influence of process parameters on the quality of necking.The thesis introduces the manufacture process of heat pipes and the requirements of necking, and analyzes several commonly used methods of necking. Then the mandreless rotary swaging process is selected as the necking process and the operating principle of rotary swaging is elaborated. The relationships between spindle speed n, roller radius r, hammer radius Rh, collar radius R and forging frequency ?? as well as forging stroke δ are obtained. The force situation and mental flow of the thin-walled copper tube during the forging process are analyzed, and the geometry of dies is optimized.The software MSC.Marc is used to establish finite element model of rotary swaging process and the forming process is simulated. The single factor method is used to analyze the stress and strain distributions under various process parameters.Touch-screen and PLC etc. technology are applied on the servo automatic necking equipment. After selecting and checking the key components, the power circuit, control circuit and pneumatic circuit are designed. The program of the touch-screen interface and PLC are compiled. Finally, the equipment is successfully assembled and debugged. The single factor method is used to analyze the necking quality under various process parameters, including the feeding speed, die angle, necking coefficient, die numbers, hammer radius and die edge shapes. The results show that:(I) the larger the feeding speed, the lower the elongation of copper tube;(II) the larger the die angle, the lower the production efficiency and elongation of copper tube.(III) the smaller the necking coefficient, the lower the production efficiency and the larger the elongation of copper tube;(IV) compared with R21 hammer, the production efficiency and elongation of copper tube are lower when R27 hammer is used;(V) compared with 4dies, the production efficiency and elongation of copper tube are lower when 3 dies are used;(VI) the necking quality of the transitional edge dies is better than a sharp edge. In addition, metallographic analysis and digital microhardness test are used to investigate the change of grain and hardness of the thin-walled copper tube after swaging, and the relationships between the feeding speed, necking coefficient and necking precision are studied. The research provides effective guidance to improve production efficiency by choosing reasonable parameters.