焊接顺序对大型薄板装甲钢结构焊接变形的影响

基于有限元软件SYSWELD建立了大型薄板装甲钢结构的焊接有限元模型,采用Local-Global方法研究了焊接顺序对薄板结构焊接变形的影响. 通过对比焊缝截面宏观形貌,利用SYSWELD热源拟合工具,建立了适合现场焊接工艺的双椭球热源模型. 采用热弹塑性有限元法分析了T形和对接接头的焊接过程,获得了局部塑性应变和焊缝刚度,进而模拟了不同焊接顺序下薄板结构变形情况. 结果表明,现场焊接顺序下结构中部薄板焊接变形严重,最大变形量为9.6 mm,模拟结果与试验结果吻合较好;采用优化的焊接顺序,可有效控制薄板焊接变形,最大变形量可减小75%.

Effect of welding sequence on welding distortion of large-sized thin armor steel structure

The finite element model for welding of a large-sized thin armor steel structure was developed based on the finite element software SYSWELD. The influence of welding sequence on the distortion of the thin plate structure was investigated by using Local-Global method. Using heat source fitting tool in SYSWELD, the double ellipsoid heat source models which were suitable for the site welding process were established through comparing the weld cross-sections of calculation and experiment. The welding procedures of both T-joint and butt joint were analyzed by the thermal elastic-plastic finite element method. The local plastic strain and the joint stiffness were obtained. Furthermore, the distortion behaviors of the thin plate structure in different welding sequences were simulated. The results show that the welding distortion of the medium plate is severe, and the maximum deformation is 9.6 mm. The calculated results agree well with the experimental ones. The distortion of the thin plates is improved effectively by using the optimized welding sequence. The maximum deformation is reduced by 75%.