用数值模拟方法优化列车转向架侧梁焊接工艺的研究

基于ANSYS平台热弹塑性有限元分析，利用APDL语言，采用单元生死技术模拟焊缝形成过程，对B型列车14t转向架侧梁的焊接残余应力与变形进行了模拟。结果显示，侧梁沿x方向（即焊缝方向）产生了收缩，两端向中心的收缩量大致相等，其值分别为0．846mm和-0．935mm；在Y方向上，上盖板沿Y的负方向产生了较大的变形，其值为-1．548mm，下盖板的位移较小，最大值仅为0．213mm；z方向上，由于约束较强，其变形值较其它方向相比大约小一个数量级。等效残余应力在焊缝上最大，其峰值约为270MPa，随着与焊缝中心距离的增加，其值迅速减小。总体而言，模拟结果符合焊接理论，且与实际情况吻合，证明了用数值模拟方法进行焊接工艺优化的可行性。

Research on Optimization of Welding Technology for Side Beams of Train Bogie by Numerical Simulation Method

The distribution of the welding residual stress and distortion of the B model train bogie side beam is simulated by the ANSYS program combined with APDL language and element birth and death technology. As the results show, the peak value of deformations along the x axis in both ends are 0. 846 mm and - 0.935 ram, respectively. The deformation in the upper cow：r plate is 1. 548 mm along the negative direction of the y axis, while the value in the under cover plate is 0.213 mm, much smaller than that in the upper cover plate. Due to the constraints, the deformation along the z axis; is far less than other two directions. The peak value of Von Mises stress appears in the center of the welding line is 270 MPa, and the value decreases rapidly as the increase of distance from the center of the welding line. In general, the simulation results show very good consistency with the welding theory and the actual welding process, which proves that it is feasible to optimize the weld technology of the side beam using numerical simulation method.