A non-finite element approach for tubular hydroforming simulation featuring a new sticking friction model

A new analytical (non-finite element) model for simulation of tubular hydroforming plane sections has been introduced. Unlike previous analytical models found in literature, the proposed model is capable of handling friction contact effects for near arbitrary cross sections through the employment of a new friction model. Although both burst pressure and final corner-fill radii can be predicted by the proposed model, the focus of the study is upon the final membrane hoop strain distribution. For both zero-friction and sticking-friction conditions, excellent agreement is observed among the proposed strain solutions and those from the finite element method for square die cross sections. For more arbitrarily defined die cross sections, reasonable agreement is observed among the proposed strain solutions and those from the finite element method. The proposed model has been introduced as a very early design/analysis tool. Therefore, it serves as a compliment to (not replacement for) the finite element method. If handled judiciously, use of the proposed model can lead to (1) reductions in the number of design iterations (2) reductions in manufacturing costs and (3) overall improvements in product quality.