摘要
套管修复是一种重要的在役焊接修复技术,然而在操作过程中由于内压和温度场的影响会不可避免地产生焊接残余应力,对应力腐蚀开裂造成很大的影响。本文采用有限元法对套管修复产生的焊接残余应力进行研究,编写了套管修复纵向双工焊接和环向焊接的移动热源子程序,与套管内压进行耦合计算,得到了套管温度场及应力场分布规律。结果表明,环焊缝焊接接头处产生的环形应力最大,轴向应力次之,径向应力最小。内管上纵焊缝区域的残余应力很小,对内管强度不产生影响。在套管纵焊缝和环焊缝的T型接头处的应力水平较高,已经达到材料屈服强度,成为最薄弱环节,应该引起足够的重视。
Casing repair is one of the important in-service welding repair technology. Due to the influence of internal pressure and temperature, the welding residual stress was inevitably produced in the process of operation,then the factors have a great effect on stress corrosion cracking. The welding residual stress of casing repair was studied by finite element analysis.The longitudinal duplex heat source subroutine and hoop moving heat source subroutine was developed. After calculation,the distribution of stress and temperature field was obtained. The results show that, the largest hoop stress is produced in the circular welding joints, and the minimum stress is radial stress. The residual stress on the longitudinal welded area of internal pipe is very small and have no effect on pipe strength. However, the residual stress on the T joint of longitudinal weld and circumferential weld is higher, and it has excessed the yield strength of the material, then more attention should be paid to the weakest section.
出处
《热加工工艺》
CSCD
北大核心
2014年第19期186-189,共4页
Hot Working Technology
基金
国家自然科学基金资助项目(51105380
11372359
51105383)
关键词
在役焊接
焊接残余应力
有限元
套管修复
in-service welding
welding residual stress
finite element analysis
casing repair
