文献类型：会议论文

英文题名：Limit loads for part-through surface axially cracked elbows under internal pressure

作者：Wang, Chen[1];Wang, Yinpei[1];Li, Peining[1];Chen, Jin[1];Sun, Xiaoming[1]

机构：[1]East China Univ Sci & Technol, Key Lab Safety Sci Pressure Syst, Minist Educ, Sch Mech Engn, Shanghai 200237, Peoples R China

会议论文集：International Symposium on Structural Integrity (ISSI 2010)

会议日期：OCT 21-24, 2010

会议地点：Shanghai, PEOPLES R CHINA

语种：英文

外文关键词：Cracked elbows; Limit loads; FE analyses; Internal pressure

摘要：Elbow is a type of components which has been widely used in a piping system. In practice, the existence of cracks in excess of the defect limits cannot be excluded. So it is very important to know the effect of cracks on the limit loads of elbows for integrity assessment of the piping system. The existing closed-form solutions for limit loads of axially cracked elbows under internal pressure are either too conservative or inadequate. The present studies focus on plastic limit loads of pressurized elbows with part-through surface axial cracks with constant-depth rectangle configurations. The crack-like defects are postulated to be in extrados, crown or intrados of elbows with different sizes. The limit loads and residual strength factors (RSFs) of cracked elbows with the connecting tangent pipes are investigated in detail, by use of three-dimensionally (3D) non-linear finite element (FE) analyses. The elastic-perfectly-plastic material behavior and geometric nonlinearity are taken into account. The results from comprehensive parametric studies indicate that the limit load of cracked elbows may reduce with increasing of crack length and crack depth, and these trends are more serious for long radius elbows under internal pressure. Base on extensive" limit load numeric data and comprehensive parametric studies, the revised closed-form equations for cracked elbows under internal pressure, involving effects of tangent pipes, are established respectively. The results can be used for "fitness-for-service" assessment of elbow.