The Finite Element Numerical Simulation And Optimizing Design For The Frame Structure Of Multi-point Forming Press

Multi-point forming(MPF) is an advanced method for sheet metal formingwhose principle is that solid dies are divided into discrete small model units, whichare substituted for a series of regular arranged and height adjusted elements.Because the height of the elements of which form the desiring surface is controlledby computer, the sheet metal can be rapidly and flexibly formed without the needfor solid dies. The four column MPF presses are one of most important products in the MPF,we have successfully developed a series of equipments. The press frame, as thefundamental support for the component of forming press, is foundation ofinstallation and fixation for other parts. In the working process, it endures thenominal load, and its design quality will directly affect the using quality of pressand the cost of manufacture. Intensity,rigidity,reliability and stability of frameplay an important role in the performance of MPF press. In this thesis, intensity andrigidity analysis of the frame structure of 3150kN MPF press has been studied. To solve the problem of the complicate design, the most perfect or appropriateof numerous design schemes are found because FEM method is introduced to theoptimizing technology. Moreover, efficiency and quality of design are greatlyenhanced. We optimized worktable, movable beam and top beam of MPF pressrespectively by finite element and Sub-problem optimized arithmetic, which arealso important content in the thesis . 1) Research on finite element method The primary principle of the finite element method, primary equations of 3Delastic issue and its finite element method are briefly explained. The choice schemeof element type in the frame analysis and some principles for meshing arediscussed, such as choice of the number of meshes, treatment of meshes density,choice of element order and judgment of mesh quality and so on. Moreover, the 68摘 要FEM simplicity model of press frame, simulation of load restriction and the way ofbuilding the finite element model are discussed. 2) Study on numerical simulation for the whole frame Established the parameter solid model for the frame of MPF press bythree-dimensional CAD software, simplified the model and then imported themodel into FEM software to numerical simulation. By given actual workingconditions to numerical simulation, stress and strain distribution of nodes for everypart of top beam, worktable and vertical pole and nut of press are obtained. 3) Study on numerical simulation for top beam of MPF press According to the result of numerical simulation for top beam, theunreasonable parts are improved for its configuration. By appending a supportboard hole for vertical column in the middle part of top beam, the height of supportboard around hydraulic cylinder is decreased. Through structure improvement, thewhole intensity of top beam is obviously improved and the whole weight islightened. 4) Study on numerical simulation for worktable of MPF press According to numerical simulation for every place of press worktable, theunreasonable part of worktable is improved. By appending a support board at thebottom of top plate in worktable, the whole rigidity is improved. Analyzed theeffect rule of the radius of hole on the worktable to other parts, such as the intensityof middle part of worktable, the intensity and distance of top board. At the sametime the rule of the wideness of middle structure impacting the intensity andrigidity of top board is concluded. 5) Optimizing design for MPF press Based on the finite element and Sub-problem optimized arithmetic, optimizedprograms of worktable, movable beam and top beam of MPF press wererespectively programmed, and then optimized the whole MPF frame. Throughoptimizing analysis, the weight of worktable reduced 6.5 percent, intensityincreased 13.2 percent; the weight of movable beam reduced 26.4 percent; the...