八万吨模锻压机主缸焊接应力场有限元分析

针对八万吨模锻压机主缸焊接应力和变形难于精确控制的问题，建立了主缸焊接有限元模型，通过模拟计算和试验验证，得到了主缸焊接温度场、应力场和变形.结果表明，主缸焊接过程中焊缝温度最高，约为2 100℃，接头区域温度梯度最大.主缸焊后最大位移位于主缸顶部，位移量约为7.4 mm，焊缝区位移量较小.在焊接前应考虑对主缸底部和顶部进行约束，防止焊后产生较大变形.主缸焊缝区等效应力最大，约为470 MPa，热影响区应力次之，母材应力最小.在热处理前要注意接头上表面是否存在焊接裂纹等缺陷.以上结果为主缸实际焊接提供了计算数据参考.

Finite element analysis on master cylinder welding stress field of 80,000 tons of die forging press

In order to investigate welding stress distribution and deformation of master cylinder on 80 000 tons of die forging press, the master cylinder welding simulation model were built using finite element method, and the results of the master cylinder temperature field, stress and deformation were obtained. The results show that the maximum temperature of master cylinder is about 2 100 ℃, appearing in the weld area, and the maximum temperature gradient occurs in the joint area during the welding process. After the welding, the maximum displacement of the master cylinder is about 8 mm, located on top of the master cylinder, and the displacement amount of the weld zone is smaller compared to top of the master cylinder. In order to prevent large deformation and ensure assembly accuracy after welding, the displacement at top and bottom of the master cylinder must be constrained before welding. The maximum stress of master cylinder is about 470 MPa, appearing in the weld area, the stress in heat-affected zone is lower, which followed by the base metal zone. Before the heat treatment, it should be checked whether there are cracks on the surface of welding or other welding defects. These results can provide calculated data reference for actual production of the master cylinder.