【摘要】 对数值模拟焊接技术在水轮机转轮上的实际应用案例进行了分析。通过采用焊接数值模拟技术对原焊接工艺方法进行优化,将优化的焊接工艺用于真机转轮的实际焊接过程。结果表明:叶片焊后残余拉应力出现在焊缝及其附近区域,并且在叶片出水边的熔合线附近出现了峰值。在转轮的焊接过程中采用先焊两端、后焊中间的方法,可以降低叶片危险区域的拉应力峰值。合理地分段方法可使叶片出水边的危险区域产生横向残余压应力,从而有效地降低了转轮开裂的风险。更多还原

【Abstract】 Application of numerical simulation welding on the hydro-runner has been analysed in the paper. Original welding procedure has been optimized with welding numerical simulation methods, and optimized welding procedure has been applied during actual welding of hydro-runner. The results show that welding residual stress of hydro-runner blades appeared on the weld or near the weld, and peaking stress appeared near the fusion line of the blade outlet edge. The method of subsection welding in which the prior welding section is the two end and latter welding section is in the middle can reduce welding residual stress of blade outlet edge’s dangerous region. Transverse residual compressive stress can be formed in the outlet edge’s dangerous region with reasonable subsection welding methods, and then effectively reduce crack risk of hydro-runner.更多还原