ESDU 75014 gives curves for the flexibilities of@ and the maximum von Mises-Hencky equivalent and the maximum circumferential stresses in@ thin smooth unpressurised pipe bends under pure bending in the plane of the bend. The curves were obtained using a finite element program and are applicable to bends with tangential straight pipe attachments whose length exceeds six times the bend radius.
ESDU 75014-1975 history
1975ESDU 75014-1975 Flexibilities of and stresses in thin pipe bends under in-plane bending: influence of bend angle and tangent pipe ends.