Thin-walled tube bending has found many of its applications in the automobile and aerospace industries. This paper presents an energy approach to provide the minimum bending radius, which does not yield wrinkling in the bending process, as a function of tube and tooling geometry and material properties. A doubly-curved sheet model is established following the deformation theory. This approach provides a predictive tool in designing/optimizing the tooling parameters in tube bending.

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