输油管道环焊缝缺陷疲劳寿命评估

摘要

采用管道失效评估方法可评估静载荷作用下缺陷是否满足适用要求.但在内压等交变载荷作用下,输油管道环焊缝仍存在疲劳破坏的可能.为评估管道环焊缝缺陷的疲劳寿命,进行管道母材和环焊缝疲劳裂纹扩展速率试验,并分析和统计管道实际运行压力数据以及环焊缝缺陷开挖验证数据,采用BS7910标准方法计算疲劳寿命值.结果显示在仅考虑管道内压波动情况下,管道环焊缝平面型缺陷的疲劳寿命结果满足管道设计使用要求.%The method for pipeline failure evaluation was used to assess defects whether meet the applicable requirements under the static load.But the girth weld of petroleum transmission pipeline still exists the possibility of fatigue damage under fluctuating load,such as internal pressure.In order to assess the fatigue life of girth weld defects, fatigue crack growth rate tests for base material and pipeline girth weld fatigue crack were conducted, and the fatigue life was calculated adopting standard method BS7910 based on actual operation pressure and girth weld defect excavation validation data by analysis and statistics.The results show that piping girth welds planar defects fatigue life results meet the operating requirement of pipeline design under the condition of only considering the pipe inner pressure fluctuations.