| Compared with riveted and welded structures, the over-all aluminum wallboard profiles (wallboard or profile in short term), have the advantages of high strength/density ratio, fine airtightness and reliable properties, being widely used in ship, traffic and special containers etc. However, because of great width/height ratio (above 50~100), shape complexity, high precision, and large dimensions of the wallboard, it is recommended that the profiles be extruded by the flat receptacle in large extruder. By far, the design and manufacture technology of the flat receptacle have not been pleasingly solved. Therefore, it is important to work on the strength analysis and design method of the flat receptacle for large profiles. Furthermore, the work can reduce the import of extrusion dies for large profiles and improve the quality of extrusion dies.With theoretical analysis, numerical simulation and physical simulation, the strength, deformation, optimization and CAD system of extruding profile die are investigated and verified on experiment. Then, some important and practical conclusions and achievement are obtained.Firstly, the key technology of numerical simulation theory is discussed to offer the technique support to subsequent analysis. Then, the numerical simulations for cylindrical and the flat receptacles are made by contact element and coupling method. The FEA model of prestressed cylindrical receptacle is built, and it shows contact element can be applied to simulate shrink-fit by the comparison with theoretical solution. After that, the planar and 3D FEA models of prestressed flat receptacle are built. Moreover, the flat receptacles under the conditions of pressure, prestress, thermal load and their coupling load are simulated respectively, and get the corresponding results and causes.In order to get the stress analytic solution, the stress equations are deduced with conformal mapping method and residue theorem, the defaults of equations in the reference are corrected. This method overthrows the obstacle in the engineering stress calculation for the flat receptacle with conformal mapping. In this paper, the stress calculation of pressed flat receptacle is developed.Using the established FE model, the deformation Law and displacement distribution of the flat receptacle are researched. Then, the concept of changeable shrinkage (CS) design is initialized. After analyzing the influence of gap ration (Km) on the deformation of major and minor axis, the Km span is obtained. During analysis, the implement and verification of CS are presented, the new die-repair process, CAE-----data processing----deformation curves fitting---CAM---accuracy test, is established. These results give support to mold repair, design of shrink-fitting and structural optimization.The structure optimization for the flat receptacle under the condition of ellipticity is proposed. By comparing with the numerical results of different ellipticity, the ellipticity span to reduce the unevenness is got. The feasibility of elliptical inner layer is also got. According to the characteristics of ellipticity and deformation of the flat receptacle inner-hole, the model for structure optimization of the flat receptacle is built combined with FEM and argumented multiplier method, the structure of the flat receptacle is optimized, and the optimal ellipticity and shrinkage are obtained.The Law for the axial, radial and tangential stresses along the flat receptacle sidewall is obtained by photoelastic experiment.Finally, all the design experiences are introduced into mould CAD system. The CAD system and its framework for profiles have been built based on RDBMS and neural net. In this system, message trigger control mechanism, the fact base and knowledge base based on RDBMS, and the intelligent inference engine based on OOP are introduced respectively. Using the ActiveX Automation technology, CAD can be seamlessly integrated. Furthermore, the bottleneck of preprocessing occurring in extrusion die CAD expert system for wallboard can be solved...
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