大直径薄壁核电环类铸件焊接防变形技术

摘要

测量大直径、薄壁核电环类铸钢件在焊接工序的尺寸变化情况,利用因果图和“FMEA”分析方法,找出了环类铸件焊接变形的成因.从增强铸件的刚度、控制焊接部位的热输入量、合理安排焊接顺序、焊后消应力等方面,采取一系列改进措施,有效防止环类铸件焊接变形.%The cause of welding deformation has been analyzed through tracking and measuring the size of large diameter thin-wall ring-like castings used in nuclear power during the process of welding. Using analysing method Fish-bone and FMEA to find the important reason of welding deformation. Welding deformation has been prevented when a series of measures for improvement have been performed including improving the castings strength, controlling the heat import of the welding zone, choosing the right welding order, decreasing stress of castings through certain method to remove the inner stress of castings after welding (PWHT).