Investigation of Effect of Process Parameters on Protrusion Height of Branched Parts in Tube Hydroforming

In tube hydroforming, by applying internal pressure using a fluid such as water or oil, bulging is created in the tube and the tube conforms to the inner walls of the die. In this paper, using hydroforming process in manufacturing of a branched joint with two branches on copper tubes has been investigated. This type of joint is used in various fluid transmission lines. Simulation of the forming process has been done in Abaqus finite element software. The effect of four important process parameters on the quality of the formed product has been studied. Considering the complex shape of the desired product, effect of four parameters of initial feeding, final feeding, yielding pressure and bursting pressure have been investigated and the effect of these parameters on the height of the formed branches and the maximum thinning has been determined. The results showed that with the appropriate selection of process parameters, a product with two branches with good quality can be obtained in one forming step. The most effective parameter on the height of the formed branch is the final feeding, so that increasing final feeding leads to more height of formed branches. On the other hand, bursting pressure has the most important parameter affecting the thinning. The initial feeding has the least effect on the thinning and the height of the formed branch.