振动时效对大型折弯焊管应力的影响

The Effect of VSR on the Stress of Large-Dimensional Welded Pipe with Bending Formation

应用振动时效工艺处理大型折弯成型直、弯焊管.结果表明:振动时效对铸态组织(焊缝)有良好的消应力作用,但对于经冷塑性加工的组织消应力效果不理想;时效后焊缝的平均最大主残余应力明显下降,而折弯处的平均残余应力有所升高;弯管中端头和中央部分的残余应力有明显的差别.

Vibratory stress relieving （VSR） was applied to large-dimensional straight and bending welded pipes with bending formation. The results indicate that VSR has positive effect on as-cast structure such as the weld beam, but has unfavorable influence on structure with cold plastic forming. The average value of the maximum residual stress in the weld beam is decreased significantly after VSR, while the stress in the bending line is increased. The difference between the pipe end and the pipe center in residual stress is evi dent,