Modeling and Simulating for Multi-pass Welding Process of Large Welded Structures

The simulation model for multi-pass welding process of large welded structures would exceed acceptable computational capacity due to large element numbers and too many increment steps. So, the FE model must be meshed with a certain mesh density. In this paper, a welded railway bogie frame is given as an example to study the issue. The related model is built by using solid and shell elements together, and shell elements are used to achieve the transition between 3D and 2D elements to avoid the convergence problem leaded by rigid link. And then, the multi-pass welding deformations are simulated on Sysweld platform by using the average welding thermal cycles on the basis of the reasonable welding lines division. It indicates that these methods are feasible for simulating multi-pass welding process of large welded structures by comparing the computed results with the corresponding actual measured values. The work would also be useful for optimizing welding sequence, clamping position, and process parameters of large welded structures.