The purpose of this study is to investigate the effect of pressure on the strain and stress analysis of pipe elbows subjected to in-plane bending moments. A finite element model for the bend was constructed and loaded with a pressure of 1200 psi and end moments taking geometric and material nonlinearities into account using (ABAQUS) nonlinear finite element code. The pressure changes the effective stress distribution and location of the initial yielding from the inside surface of the elbow crown to the outside surface for the closing moment case and increases the moment of yielding. For the opening moment case, yielding starts at the inside surface of the elbow crown with and without pressure. The pressure changes the location of the maximum axial strain at instability for the closing and opening cases, and it also changes the ovality of the cross section in both cases.

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