Flight Vehicle Sheet-metal Processing Technology And Theoretical Analysis

The technological design is the basis of the modern enterprise. The technological work runs through the whole process of aircraft's research,design,trial manufacture,final design and production and it is also the main base of the aircraft's development and production. There are a lot of sheet metals in the aircraft. The basic methods of producing sheet metals include blanking,bending,deep drawing forming and so on.Some things about bending,deep drawing,and flanging in forming process are deduced detailed based on the theory of the plastic mechanics, using the common method which is used for solving the problems of sheet forming, that is incision microbody method. First, the distribution law of stress and strain is deduced when the wide boards or the narrow boards are bending and the formula used for calculating the bending moment is also deduced. Their deformation features and the failure form are analyzed. Then methods are brought forward to control the failure. Moreover the calculation means is explained through the examples. Second, the deformation process and charicristic of cylinder component when it is deep drawed are got, the distribution law of stress and strain of the flange deformation zone and load transferring zone of tube wall are obtained, the failure form is studied ,and then the measure is presented. In addition the calculation method of drawing coefficient and drawing times in deep drawing process is illustrated through examples. Third, the distribution law of stress and strain of the deformation zone of hole flanging plane is derived, the failure form is also analyzed, and finally the way which. used to control the failure is provided. Using the example, how to calculate flanging coefficient in hole flanging process is accounted for.Innovation of this paper is that it connects the theory of plastic mechanics and process technics. The section which stress and strain is concentrated anddiscontinuous is found because it is usually the destruct part of blank sheet in act. That the solving ways can be given according to the actual condition. Namely, the cause of failure is explained in the point of plastic mechanics, according to the actual condition adopting methods to decrease the chance of failure. So that it can improve the process technics level.