Abstract: The effect of the deformation condition on the axial compressive precision forming process of tube with curling die was investigated by using a rigid-plastic FEM. The results show that the forming accuracy depends mainly on geometric condition r(ρ)/d(0), little on tube material properties and friction condition, the relative gap Delta /2r(ρ) of double-walled tubes obtained decreases with increasing r(ρ)/d(0), and there is a parameter k for a given t(0)/d(0) or r(ρ)/t(0), when r(ρ)/d0 > k, Delta /2r(ρ) < 1, otherwise /2r(ρ) > 1.

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