Stresses and strains determination of welded pipelines with the mild interlayer at plane stress state under elastic-plastic loading

Abstract

Dependence of stress strain state components on pressure, relative thickness of welded pipelines wall and mechanical heterogeneity of the welded joints materials is analyzed in this paper. It is determined that the mechanical heterogeneity parameter γ N of welded joint increases with increasing elasto-plastically deformed zone at the contact plane, pressure p and ratio M e H e e γ =σ σ . The most loaded zones are at the inner surface of the pipe: at the contact plane for hard metal and at the centre of a mild interlayer. The stresses and strains calculated analytically in the separate zones of welded pipe and determined by FEM showed a good agreement.