基于数值分析法的真空室组对焊接热变形及影响因素分析

Study of thermal deformation and its influence factors during vacuum chamber assembly and welding by numerical analysis method

焊接过程中大型薄壁曲面零件的变形控制是影响其质量的关键。文章以真空室的组对焊接为对象,基于有限元热-结构耦合方法,研究焊接变形和真空室曲率大小之间的关系,探究夹持点位置和个数对真空室焊接变形的影响。结果表明,真空室的曲率半径越大,焊接变形也越大。研究得出减小焊接变形的措施为:对于真空室中曲率半径较小且长度较短的圆弧处,应不予夹持或仅中点夹持;对于曲率半径较大的圆弧处,应均匀布置较多夹持点;对于不同曲率的圆弧过渡处,应予以夹持、且靠近较大曲率圆弧处应施加额外的夹持。该研究为真空室以及类似薄壁曲面零件的焊接提供一定的技术指导。

Control of welding deformation is the key factor affecting the quality of welding large and thin-walled components with curved surface. In this paper,thermal-structural coupled method with FEM is used to study the relationship between welding thermal deformation and vacuum chamber curvature radius,and explore the effects of clamping position and number on welding thermal deformation during vacuum chamber assembly and welding. The results show that welding deformation enlarges as the curvature radius increases. The following measures help to reduce the welding deformation: for those curves of smaller curvature radius and shorter length,the clamping should be canceled or set at the middle of the curves;for those of larger curvature radius,more clamps should be evenly arranged;clamps should be set at the transition of different curves and extra clamps should be laid near the curves of bigger radius. The research can provide technical guidance for the welding of vacuum chamber and similar thin-walled components with curved surface.