Study On Tube Straightening Process Of Micro Thin-walled Copper Tube And Device Development

With the development of miniature, ultra-thin and portable electronic products, a seriesof problems emerge, such as smaller space of electronic components for heat dissipation andhigher density of heat flow rate. Traditional cooling methods have been unable toaccommodate the future development requirements of advanced electronic components. Heatpipes, based on the phase change heat transfer theory, have been the ideal components forcooling devices with high density of heat flow rate owing to the good thermal conductivity.The straightening process is a key procedure in micro heat pipe manufacturing, and thestraightening quality affects the heat transfer property, appearance of heat pipe and thesubsequent processes. Three parallel rollers straightening and parallel plants straighteningprocess are two extensively methods adopted in micro heat pipe manufacturing. Experimentsand finite element method (FEM) are utilized to investigate these two processes. Main factorsof the straightening quality are studied and straightening device for actual producing has beendeveloped eventually.Firstly, main factors are obtained including tube status, outer diameter, originalstraightness, stroke and speed, by preliminary analysis of these two processes. According tothe main factors and their levels, orthogonal test is used to design experiments. Secondly,experiments of two straightening processes are carried out. The relationships between mainfactors and straightening quality are analyzed, process capability and optimal processparameters are obtained. Thirdly, finite element models of straightening processes of microthin-walled copper tube are established, deformation. Distribution of stresses and strains,loads of rollers and plants during processes are researched, and simulated results are veriedwith the experimental results. Finally, by summarizing simulated and experimental results,straightening device of micro thin-walled copper tube for actual producing has beendeveloped according to optimal process parameters and loads.