Preprocessing Of Welding Fe Simulation And Its Application In Welding Sequence Optimization For Missile Oil Tanks

As a result of high speed evolution in computer science, the applications of Finite Element Method (FEM) were developed in theoretical and practical researches of welding, which got more and more attentions from numerous enterprises. The final goal of these researches was using FEM to solve the problems in the manufacture and production. However, some things limited the development of FEM technology in China. For example, most of the simulation software was from the developed countries like Europe and America, and this software was not easy to operate with a complex interface in English and not specialization in the particular research field or special purpose. To solve these problems, a FEM preprocessing system in materials joining process has been developed in this dissertation. Based on this system, a welding numerical model of a missile's oil box has been established and the structure's distortion rules after welding have been analyzed.The control panel of this preprocessing system is simple and convenient. The friendly interface between computer and human allows the users easy to complete all the preprocessing operations, including the model's meshing, the setup of the material parameter and welding processing parameter, the initial conditions and boundary conditions'definition etc, preparing for the simulation subsequently. So any operator with lack of knowledge in FEM or English can finish the welding simulation during using this preprocessing system.As an application of this FEM preprocessing system, the simulation on the welding process of missile's oil box was performed, in which the effects of the welding sequences of four web plates and welds on each web plate are primarily analyzed. The simulation results show that the deformations under varied welding sequences are almost the same. Downward deflection deformation is obtained along the weld longitudinal direction in the structure as well as upward deflection deformation along the weld traverse direction. The welding start location has little effect on the deformation of the structure. The minimal deformation of the structure is obtained using the method presented as follows: four web plates are first tack welded on both ends, and then the web plates are...