The Effects And Optimization Of Key Parame-Ters In Multi-pass Conventional Spinning Of Curvilinear Generatrix Parts

Curvilinear generatrix revolving body include diversified kinds of hollow revolving parts such as vessel head, hemisphere, bell-shaped nozzle and hybrid parts. It is widely used in fields as aviation&aerospace, appliance and musical instruments. Metal Spinning, working as the advanced technology in manufacturing hollow revolving bodies with chipless and strength improvement properties, nowadays has become a preferred forming technology in the processing of curvilinear generatrix parts. In this paper, a3D elastic-plastic finite element(FE) model for the multi-pass spinning with curvilinear generatrix part was developed to explore its forming mechanism and the relationship between key parameters and the forming quality. The robust optimum design was made for key processing parameters and the trajectory parameters was optimal designed through deformation allocation.Contents of each chapter list as follows:In the first chapter, the development situation of spinning technology was outlined, and also the main problem of curvilinear generatrix parts during multi-pass conventional spinning process was introduced. Then, the current study status at home and abroad and the research trend of spinning technology were summarized. In addition, the applications of finite element in spinning was outlined, and the primary research contents and the structure of this paper were givenIn the second chapter, the deformation theory of curvilinear generatrix parts during multi-pass conventional spinning process was discussed and a3D elastic-plastic finite element(FE) model was developed. Then the theory of elastic-plastic deformation was analyzed, including the stress-strain state and deformation theory. A3D elastic-plastic finite element(FE) model was developed and verified, which makes the simulation more consistent with the actual production status.In the third chapter, the key parameters of curvilinear generatrix parts during multi-pass conventional spinning process was researched, including key process parameters and trajectory parameters. Numerical simulation was used to forming mechanism. In addition, three the key process parameters including the rate of feeding, spindle speed and the roundness radius of roller were studied by using single factor analysis method. The trajectory parameters was also researched based deformation allocation.In the fourth chapter, the research about the key process parameters optimization on robust design optimization was caught. Through robust design requirements, the orthogonal experimental was designed and the optimized parameters was obtained meeting the qualifications of wall-thickness and fittability by using extreme difference analysis method and comprehensive evaluation method.In the fifth chapter, the trajectory parameters was researched based deformation allocation on multi-pass conventional spinning process with curvilinear generatrix parts. Through the study of deformation allocation, the influence of the trajectory parameters on thickness distribution and fittability was analyzed. Roller path profiles were designed according to three patterns of deformation allocation based on the theoretical method, including equal max. deformation, equal arc length and equal axial distance. Then the trajectory parameters was optimized based on the evaluating of the deformation allocation.In chapter6, the research results of this subject were summarized, and the future research direction are expected.