Creep flexibility and stress factors for pipe bends with end constraints under in-plane or out-of-plane loading

Theoretical analyses are presented for the creep behaviour of pipe bends with end constraints under in-plane or out-of-plane loading in the presence of steady state creep. The energy method of analysis is adopted together with an n-power stationary creep constitutive relation. Deformation results and stress concentration factors based on the straight pipe values are presented for most practical geometries of pipe bends. The application of these results to design is also briefly mentioned.