采用数值模拟的方法研究了某一核级管端法兰面在线堆焊修复过程中的焊接顺序及堆焊厚度对残余应力和变形的影响。模拟结果表明，由于法兰内外侧厚度不同以及内外壁连接管的刚性差异，采用从内至外的焊接顺序可以得到整体较小的焊接残余应力和变形。当堆焊厚度为20 mm时，外壁管道焊缝处的轴向残余应力接近材料的屈服强度；当堆焊厚度不超过15 mm时，外壁管道焊缝处的残余应力远低于屈服强度。采用优化的焊接工艺制作了等比例模拟件，并采用X射线衍射法测试模拟件的残余应力，计算结果与测试结果吻合良好，进一步验证了数值模型及模拟分析结果的可靠性。
Numerical simulations were used to study the effect of welding sequence and surfacing thickness on the residual stresses and deformation after on-line surfacing welding repair of the flange surface of a nuclear grade pipe. The simulations show that the welding sequence from the inside to the outside wall leads to smaller residual stresses and deformation due to the different thicknesses of the inside and outside walls of the flange and the rigidity differences between the connecting pipes. With a 20 mm surfacing thickness, the residual axial stress at the welding seam of the outer pipe wall is close to the material yield strength. With surfacing thicknesses no more than 15 mm thick, the residual stress at the welding seam of the outer pipe wall is far lower than the yield strength. A sample specimen was made using the optimized welding process with the residual stress then measured using X-ray diffraction. The predicted stresses agree well with the measured data to verify the simulation results.
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