Elastic-plastic finite element analysis has been carried out to evaluate collapse moments of six elbows with elbow factors varying from 0.24 to 0.6. The loading conditions of combined in-plane closing/opening bending moment and varying degree of internal pressure are considered in the analysis. For each case, collapse moment is obtained by twice elastic slope method from the moment versus end-rotation curve. Based on these results, two closed-form equations are proposed to evaluate the collapse moments of elbows under combined internal pressure and in-plane closing and opening bending moment. [S0094-9930(00)00103-7]

Issue Section:
Technical Papers
Keywords:
finite element analysis, pressure vessels, internal stresses, bending, deformation, failure (mechanical), Collapse Moment, Finite Element Analysis, Elbow
Topics:
Collapse, Finite element analysis, Pressure
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