文献类型：期刊文献

中文题名：内压载荷作用下含纵向穿透裂纹弯头的塑性极限载荷

英文题名：COLLAPSE LOADS FOR CRACKED ELBOWS UNDER INTERNAL PRESSURE

作者：王辰[1];李培宁[1];樊延松[2];秦宜奋[1]

机构：[1]华东理工大学机械学院,上海200237;[2]辽河石油勘探局装备工程公司研究所,辽宁盘锦124010

年份：2006

卷号：28

期号：3

起止页码：377

中文期刊名：机械强度

外文期刊名：Journal of Mechanical Strength

收录：CSTPCD;;EI(收录号：2006279980797);Scopus;北大核心:【北大核心2004】；CSCD:【CSCD2011_2012】；

基金：国家"十五"重大科技攻关资助项目(2001BA803B03-05)。~~

语种：中文

中文关键词：弯头;塑性极限载荷;穿透裂纹;内压;非线性有限元分析

外文关键词：Elbows;Limit loads; Through-wall cracks;Internal pressure; Non-linear finite dement （FE） analyses

摘要：弯头是管道系统中最薄弱、最容易失效的管件。研究含缺陷弯头的塑性承载能力在整个压力管道系统安全评定中占有重要地位。利用求取直管极限载荷的鼓胀系数法建立不考虑直管影响的含缺陷弯头的塑性极限载荷估算式。采用三维弹塑性有限元技术,对内压载荷作用下含纵向穿透裂纹弯头的塑性极限载荷进行系统分析。结果表明,裂纹削弱系数(PL/PL0)与厚径比(t/rm)无关,在实际工程应用中可忽略厚径比对裂纹削弱系数的影响。裂纹对长半径弯头的塑性极限承载能力影响程度明显大于对短半径弯头的。
Elbow is a type of component widely used in a piping system. The existence of cracks in excess of the defect limits can not be excluded. So it is very important to know the effect of cracks on the collapse loads of elbows for integrity assessment of the piping system. The simplified estimation formulas for plastic limit pressure of cracked elbows without the effects of straight pipes were established. The influences of defects on the load carrying capacity of elbows with various bending radius （R = 1.0Di and R = 1.5Di）, were investigated in detail, by use of detailed three-dimensional （3D） non-linear finite element （FE） analyses, using elastic-perfectly-plastic material behavior and taking geometric nonlinearity into account. The crack-like defects with different dimensions were focused on axial through-wall cracks, located in extrados, intrados and crown of elbows with the welded tangent straight pipes respectively. The results from comprehensive parametric studies of limit loads of elbows indicate that the limit load capacity of cracked elbows may reduce with the increasing of crack length and these trends are more serious for long radius elbows. These is insignificant effect of t/rm on the weakening factor （PL/PLo） of cracked elbows subjected to intemal pressure.