Process Of Forming A Micro-channel Integral Finned Tube Heat Pipe Cross Rolling

The research and development of energy-efficient equipment was an important means to positive response national policy with energy-saving emission reduction. Heat pipe exchanger as a core part of new and efficient phase change heat transfer device and it had been widely applied in petroleum, chemical, metallurgy, electric power and other industries. The performance of the heat exchanger was influenced directly by the quality of the finned tube as the core part of heat pipe exchanger. At the moment, the most fins of heat pipe exchanger were made by traditional way, the integral fin tube was less and most of which were the light tube type finned tube. There was almost no integral finned tubes with micro-grooves.For the above current situation, the theory of three roll skew rolling was used and the integral fin tube technology and micro-channel heat pipe technology were combined organically, and then the micro-grooves heat-pipe integral finned tube was researched and developed in this paper. The finned tube as a core part of new and efficient heat transfer device not only has the advantage of integral fin tube, such as non-contact thermal resistant, high pressure resistant and wear resistance, but also has the characteristics of the effective phase change heat transfer of heat pipe exchanger.According to the forming principle of three roll skew rolling, through analysis, the movement characteristic of integral finned tube’s forming was obtained:the skew rolling angle equal to rising angle of spiral fin tube. The rotation conditions of rolled piece were got through study. The deformation process of rolled piece in biting segment, jarring segment and finishing segment were studied. The characteristics of fin height and ductility in skew rolling process were analyzed. The reality productive technology of the integral fin tube was studied and the major issues in the production process should pay attention to put forward.According to the forming characteristic of integral fin tube, the effect of forming with roll shape, skew rolling angle and skew rolling reduction were studied. The specification parameter of single blade with roller was researched and designed. The requirement and purpose of experiments were considered in a comprehensive way, and the five skew roll type were designed. After the study of forming process of micro-grooves heat pipe integral finned tube, the material of finned tube has been determined. For the thick-walled rolling, the forming process of set-piece, chip set-brazed and bimetal combined type were primary studied. Through experiments and analysis showed that connecting less strong, some contact thermal resistant and reducing the heat transfer efficiency were the biggest drawbacks of the integral fin tube with above three molding method.In order to find the deformation laws of the micro-grooves heat pipe integral finned tube in the rolling process, the related experiments were studied with different roll shape, skew rolling angle and skew rolling reduction in this paper. The optimum operating parameters of the forming process of rolled piece E were determined to be: skew rolling reduction of3mm, skew rolling angle of2.5°and the roll shape of V. According to the experiments, some difficult problem such as distortion on the micro-channel and the cracking on the top of external fin-tube had been studied and a better solution had been obtained.