Effects of Axial and Radial Distortion on Residual Stress of HSAW Pipe

The complex distortion often occur when the pipe sections of HSAW pipe are cut along the axis. The residual stress caused by the axial and radial distortion in the cut-ring test of HSAW pipe is studied by elastic mechanics theory in this paper, and the effects of the axial and radial distortion on the residual stress of HSAW pipe are analyzed according to the results of the cut-ring test of HSAW pipe section and the mechanical status during the forming of HSAW pipe. The research indicates that the larger axial and radial displacement shows that the larger torsion and shearing stress exist during the strip forming, and which will result in the larger residual stress. It is suggested that the axial and radial displacement in the cut-ring test shall be limited in the technical specification of HSAW line pipe for pipeline project, especially for the key pipeline project.