FEM numerical simulation of tube axial drawing process

Tube inversion by the axial drawing is an advanced forming process for manufacturing double-walled tubes with high quality, high efficiency, and low consumption. However, to realize forming process depends on producing the tearing in deforming zone, which has a close relationship with forming load. So in this paper, the influence of forming condition parameters on the deforming force and the process is investigated by rigid-plastic FEM numerical simulation. The results show that: (1) during the whole forming process, the shape of the tube remains unchanged when the radius of the core die is larger than a certain value, so a precision forming can be easily realized; (2) for a given r/d0 or t0/d0, the deforming force depends mainly on the value of r/t0, and there is a critical parameter k, when r/t0 < k, the steady forming force decreases with an increase of r/t0; on the contrary, when r/t0 > k, the steady forming force increases with an increase of r/t0; (3) the material hardening exponent n of the tube and the friction coefficient μ have a remarkable influence on the deforming force. The smaller the value of n and the larger the value of μ the larger the forming force.