Investigation of non-kinematic conical roll bending process with conical rolls

Although high quality cones can be produced with kinematic conical roll bending due to the non-slide condition between the conical rolls and the plate, the process flexibility is limited because the conical rolls cannot be reused to produce cones of different cone angles. In this paper, a non-kinematic three-roll bending process is proposed to reduce manufacture costs by reusing existing conical rolls. In this process, an attachment is added to the top edge of the plate to obtain required circumferential velocity as the top/bottom radius ratio of the desired cone is smaller than the rolls. The top sides of the conical rolls slide on the plate to reduce the local velocity near the top edge and an appropriate velocity near the top edge of the plate can be obtained by adjusting the friction coefficients between the rolls and the plate. This flexible process can provide performance similar to the kinematic conical roll bending process. The process modeling is based on the finite element method under ANSYS/LS-DYNA environment. A relation between the gap size of the bent cone and the friction at the plate/attachment contact interface has been investigated by using numerical simulations. The simulation results give a well bent cone compared with an ideal cone.