Structural behavior of solid expandable tubular undergoes radial expansion process - Analytical, numerical, and experimental approaches

Today's structures have to meet increasingly rigorous requirements during operation. The economic and human costs of failure during service impose a great responsibility on organizations and individuals who develop new products as well as those who select/integrate products in a final engineering design. A crucial aspect for successful product development and/or inclusion is the careful selection of the best material(s), derived from an informed awareness of the capabilities and opportunities afforded by all candidate materials, together with a design that takes full benefit of those competencies. Thick-wall tubular is an example where all these issues are playing a major role in deciding their industrial applications. Given for their desirable features of high strength and geometrical shape, they are widely used in aerospace, marine, military, automotive, oil and gas, and many other fields. This paper focuses on developing analytical solution to investigate the structural response of thick-wall tubulars undergo plastic deformation due to expanding them using a rigid mandrel of conical shape. Volume incompressible condition together with the Levy-Mises flow rule were used to develop the equations which relate the expansion ratio of the tubular to the length and thickness variations. Besides, Tresca's yield criterion was used to include the plastic behavior of the tubular material. Further to this, a numerical model of the tubular expansion process was also developed using the commercial finite element software ABAQUS. Experiments of tubular expansion have been conducted using a full-scale test-rig in the Engineering Research Laboratory at Sultan Qaboos University to validate the analytical and numerical solutions. The developed analytical and numerical models are capable of predicting the stress field in the expansion zone, the force required for expansion, as well as the length and thickness variations induced in the tubular due to the expansion process. Comparison between analytical, experimental, and simulation results showed that a good agreement has been attained for various parameters. © 2013 Elsevier Ltd. All rights reserved.