摘要
针对裂纹处的应力集中和分布不均匀等原因造成天然气泄露的问题,采用有限元模拟方法,通过空间模型的建立,研究裂纹尖端的应力大小和分布,得到管道的应力强度因子,并与理论值进行比较验证;综合考虑各种因素对裂纹管道应力强度因子的影响,采用CEGB R6方法评估裂纹管道的安全性.研究结果表明:管道在内压作用下,管道裂纹尖端处出现较大的应力集中现象,管道的最大等效应力出现在管道裂纹前缘,最小等效应力出现在管道裂纹的中间;随着管道直径和裂纹半长的增大,等效应力随之增大;随着管道壁厚的增大,等效应力逐渐减小;应力强度因子随着管道壁厚的增加而减小,随着裂纹半长和管道直径的增大而增大;裂缝管道脱离安全区的内压随壁厚的增大而增大,随管径、裂纹半长的增加而减小.
Aiming at the problem of natural gas leakage caused by stress concentration and uneven distribution at the crack,the finite element simulation method is used to study the stress size and distribution at the crack tip through the establishment of a spatial model,and the stress intensity factor of pipeline is obtained,which is compared with the theoretical value for verification.Considering the influence of various factors on stress intensity factors of cracked pipes,CEGB R6 method is used to evaluate the safety of cracked pipes.The results show that under the action of internal pressure,the crack tip of pipeline will cause a large stress concentration phenomenon,the maximum equivalent stress of pipeline appears at the front of pipeline crack,and the minimum equivalent stress appears in the middle of pipeline crack;with the increase of pipe diameter and crack half length,the equivalent stress increases;with the increase of pipe wall thickness,the equivalent stress decreases gradually.The stress intensity factor decreases with the increase of pipe wall thickness and increases with the increase of crack half-length and pipe diameter.The internal pressure of cracked pipes leaving the safety zone increases with the increase of wall thickness and decreases with the increase of pipe diameter and crack half-length.
作者
孙颖
袁野
吕超
SUN Ying;YUAN Ye;LYU Chao(School of Civil Engineering,Northeast Petroleum University,Daqing 163318,China)
出处
《徐州工程学院学报（自然科学版）》
CAS
2020年第4期48-53,共6页
Journal of Xuzhou Institute of Technology(Natural Sciences Edition)
基金
中国石油科技创新基金项目(2016D-5007-0608)
中国石油和化学工业联合会科技指导计划项目(2016D-7001-0705)。
关键词
管道
裂纹
泄漏
有限元
极限内压
应力强度因子
pipeline
crack
leakage
finite element
ultimate internal pressure
stress intensity factor
