核燃料筒体部件焊缝的承载性能研究

Study on the Load-bearing Performance for the Upper Shell Welds of Nuclear Fuel

不锈钢电子束焊通常被认为是手工GTAW焊的最佳升级方案,然而在某些有剪切强度要求的焊接结构中,电子束焊缝较窄的特性可能会影响其承载性能。为保证堆芯产品焊接结构可靠性,首先对比分析了电子束(EB)焊和手工GTAW焊缝的几何尺寸和承载面积,发现EB焊缝的宽度仅为GTAW焊缝的53.5%,承载面积仅为GTAW焊缝的48.8%。然后通过理论计算和工况分析,得出筒体部件焊缝的最大承载力为134765 N,而EB焊缝和GTAW焊缝的理论承载力均远大于这一值。最后,通过实物试验验证,EB焊缝和GTAW焊缝的承载性能相当,且均大于筒体部件本身结构的承载能力。最终证明EB焊缝可满足正常工况及事故工况下产品承载性能的设计要求,为核燃料国产化研究的顺利推进提供了支持。

Stainless Steel Electron Beam Welding is often considered the optimal upgrade for manual GTAW welding.However,in some welding structures with shear strength requirements,the narrow characteristics of electron beam welds may affect their load-bearing performance.Since the welds of nuclear fuel cylinder components need to withstand long-term high temperature and pressure,radiation creep stress,and chemical corrosion in the reactor core,the shear load-bearing performance of electron beam welds has been questioned by experts.To ensure the reliability of the core product welding structure,the geometric dimensions and load-bearing area of electron beam(EB)welds and manual GTAW welds were first compared and analyzed,and it was found that the width of EB welds is only 53.5%of GTAW welds,and the load-bearing area is only 48.8%of GTAW welds.Then,through theoretical calculation and working condition analysis,it was concluded that the maximum load-bearing capacity of the cylinder component weld is 134,765 N,and the theoretical load-bearing capacity of both EB and GTAW welds is much greater than this value.Finally,through physical testing,it was found that the load-bearing performance of EB and GTAW welds is equivalent and both are greater than the load-bearing capacity of the cylinder component itself.It was ultimately proven that the EB welds can meet the design requirements for product load-bearing performance under normal and accident conditions,providing support for the smooth advancement of research on the localization of nuclear fuel.