Rotational autofrettage is one of the recently proposed potential method for eliminating the in-service yielding of thick-walled cylindrical pressure vessels. &nbsp;The operating principle of the process involves rotating the cylinder about its own axis at sufficiently high angular speed inducing plastic deformation at the inner layer and subsequently bringing the cylinder to a gradual rest to introduce compressive residual stresses. A few researchers have studied the feasibility of the process theoretically and asserted certain advantages over the practicing hydraulic and swage autofrettage processes. In the literature, all theoretical analyses on the rotational autofrettage are based on the Tresca yield criterion and its associated flow rule along with the assumption of different plane end conditions (plane strain and generalized plane strain). Although Tresca criterion is used to make the analysis simple, it is the von Mises yield criterion that predicts the yielding behavior of most of the engineering materials close to the actual. It is therefore an analysis of the rotational autofrettage of cylindrical vessel is attempted in the present work incorporating von Mises yield criterion. The true plane strain condition is used for the analysis. A numerical solution methodology is followed to estimate the stress distribution during the rotational autofrettage of the cylinder. The present solution is compared with the solution predicted by Tresca criterion and an equivalent three dimensional finite element analysis using ABAQUS package. It is found that the present solution based on von Mises criterion very closely matches with the three dimensional finite element results asserting the realistic stress distribution in the rotationally autofrettaged cylinder. The maximum deviation of the present solution from the solution based on Tresca criterion is about 15%.Keywords: Rotational autofrettage, Thick-walled cylinder, von Mises, Elastic-plastic, Residual stress, Three dimensional finite element method.&nbsp;&nbsp;

Estimation of the Stresses in Rotational Autofrettage of Thick-Walled Pressure Vessels Using von Mises Yield Criterion

Paper Proceedings: https://asmedigitalcollection.asme.org/PVP/PVP2021/volume/85314

ASME 2021 Pressure Vessels & Piping Conference (PVP2021)

Supporting the need among researchers worldwide for additional online and multimedia content, ASME now offers the ASME Conference Video Collection. This platform will collect and provide long-term access to conference presentation videos, encompassing all technology areas within ASME's technical conference and events program. About 30,000-40,000 engineers across all mechanical engineering and related disciplines participate in ASME conferences each year. This includes authors of approximately 6,000 to 8,000 technical papers published by ASME, the majority of whom also submit video presentations for our virtual conferences. The video collection will be available as an add-on to existing product packages or as a separate subscription.