Simulation And Studying Of The Welding Deformation Of The Truck End Wall Structure Of P70

With the rapid development of railway in our country, higher requirements have been proposed in the production of rolling stock. As the main processing method, welding is more in the need of being researched in depth. Welding unstability deformation is a common phenomenon in plated construction. During the welding process, the compressive stress caused by the contraction of the welding joints leads to the unstabbility of the truck end wall structure, thus resulting in wave transformation, which on one hand decreases the strength of the structure, and on the other hand affects the smoothness and aestheticness of the surface. This paper adopts inherent strain finite element method, by which the whole welding process can be avoided, and the inherent strain in welding line and near weld zone after welding is noted. After finding the relationship between the value and distribution of inheren strain and welding paramater, weldment size, etc., conducting an elastic finite element calculation by taking the inherent strain as the initial strain value, and then the residual stress and deformation of the whole weldment can be obtained. In doing so, the calculation amount is reduced tremendously, and the calculation results can be more in accordance with the accuracy requirements. Firstly, in line with the actual techniques, the welding unstability deformation of the truck end wall structure is simulated. By means of making the inherent strain equivalent to the thermal load of the welding line and the heat affected zone, the critical load can be determined by linear unstability analysis, and then the size of unstability deformation can be determined by non-linear unstability analysis. The result of simulation is basically corresponding to the measured value, thus proving the correctness of the model. In the meantime, basing on the simulation model, this paper researches the influence to welding deformation which is brought by the change of linear energy, thickness of plating, and constraint conditions.