Abstract
To estimate the residual stresses and deformations due to circumferential welds of a pipe, this paper suggests the trapezoid-inherent strain model in which stresses and deformations are obtained to apply the Green function introduced by Shirakawa. The stresses and deformations calculated from the analytical model agree well with those measured in the experimental circumferential welds. Accordingly, the parameters determining the properties of the residual stresses and deformations could be derived analytically by means of the model. The parameters made experimentally proof of much suitability, are (Tav)θ.βθ{=(Q/cρhl)⋅βθ} and, βθ(=l/√ah). Where Q, c and pare net heat input per unit weld length, specific heat and density, and a, h and 1 are the mean radius, thickness and length of a, cylindrical shell respectively. The length I being sufficiently larger than a and h, the residual stresses and deformations are determined by the single parameter (Tav)θ⋅βθ.
