Research And Development Of Special Bending Machine For Large Diameter Profile

The slogan "green production, environmental protection, low consumption" has been put forward for a long time in the major industrial fields. It promotes the development and application of aluminum alloy profiles bending process by leaps and bounds in the areas of aerospace, automotive, shipbuilding and construction industries. Thus the research and development of high-precision, high automated machine for profile bending has become a widespread demand currently in various sectors. In order to solve the problem of straight-line segment after Roll Bending for large cross-section profiles, this paper developed a set of forming equipment on the basis of principles in profile bending, which was dedicated to bending the straight-line segment. It has a direct promotion and practical significance for the application of aluminum alloy profiles.After introduction of the topic background and description of the research significance, a comprehensive review was conducted in the aspects of technology development and machine application for profile bending in the domestic and outside. Based on these information, the research contents were commenced in the following aspects:The deformation theory in profile bending was studied exhaustively, and then the defect problems were pointed out in summary. To settle the problem of appearing straight-line segments on both ends of the profile after Roll Bending, which was caused by the phenomenon of material springback, the thesis put forward the way of axial-tensile and lateral-rolling on the straight-line segment. And in the form of stretch-bending with lateral-rolling, the program design of the machine layout was discussed in detail. The overall function was decomposed into three major parts:lateral-rolling component, tensile system and fixed mold table. The relative motion of the three parts was arranged in accordance with the straight-line segments bending process, to ensure the reliability and rationality of the movement.Lateral rolling mechanism was designed to double-sliding table structure, which motion form was arranged to the Cartesian coordinate and control system was designed to hydraulic and servo wholly-closed-loop; the stretch-bending system was set to provide an adequate supply of axial tensile force and to guarantee the profile section could paste its mode accurately during the bending process; the structure of the fixed mold workbench had a very high stiffness, so that the mold could be positioned exactly and fixed reliably under the tremendous tensile force.Based on the CAD/CAE technology.3-D model of the devices were completed under the engineering software Pro/Engineer by applying top-down design method and parametric modeling. Then virtual assembly and motion simulation of the components were carried out in order to check if there was volume interference or movement interference. Moreover, for the purpose of researching deformation features of the structure under loads action, the key parts of the machine were studied by finite element analysis in taking advantage of the ANSYS Workbench software, in turn improved the structure and optimized the design eventually.