中国石油大学学报（自然科学版）2017，Vol.41Issue(1)：124-129,6.DOI:10.3969/j.issn.1673-5005.2017.01.016
基于等效缺陷尺寸在役焊接安全性评价研究
Safety evaluation of service welding based on equivalent defect size
摘要
Abstract
The instantaneous temperature field of the X70 pipeline steel during in-service welding was simulated by the FEM software SYSWELD.Considering the size of the welding molten pool and the metal strength loss in high temperature areas,the equivalent size of the welding molten pool was calculated using the strength path integral method.The equivalent welding molten pool was viewed as a volume type defect,then the safety working pressure of the in-service welding was calculated based on the equivalent defect size,and the safety of gas pipelines in-service welding is evaluated.The results show that the safety working pressure increases with the wall thickness increasing,ie.it is more safe.The safety working pressure decreases with the pipe diameter increasing,but the length correction coefficient of the equivalent defect weakens this effect.The safety working pressure under the gas medium condition is smaller than that under the saturated aqueous medium condition.It is also found that the gas medium pressure and flow velocity have little impact on the safety working pressure.For a certain wall thickness,it's conservative to use the equivalent defect size under the conventional air cooling condition to perform safety evaluations.关键词
在役焊接/数值模拟/等效缺陷/安全性评价Key words
in-service welding/numerical simulation/equivalent defect/safety evaluation分类
能源科技引用本文复制引用
王勇,孙启平,韩涛,张波,卢玉秀..基于等效缺陷尺寸在役焊接安全性评价研究[J].中国石油大学学报（自然科学版）,2017,41(1):124-129,6.基金项目
国家自然科学基金项目(51074174) （51074174）
