Nonlinear analysis of pipe bends subjected to out-of-plane moment loading and internal pressure

The behavior of a pipe bend with bend factor h = 0.1615 (D = 16 in., R = 24 in. and t =0.41 in.), subjected to out-of-plane bending and internal press ure is studied, raking geometric and material nonlinearity into account. us ing the finite element code ABAQUS. Material behavior is taken as elastic-p erfectly plastic. The distribution of stress and strain along the axial dir ection and across the thickness of the bend is studied, with and without in ternal pressure, at the onset of yielding and at instability. Before instab ility is reached, through-the-thickness yielding appears at many points. Th e loaded end of the bend is found to be the most severely strained cross se ction. The circumferential distribution of stress and strain, and its varia tion with increased moment loading are then investigated for thar section, at internal pressure values of zero and 1200 psi.