Patent ID: 6912884
Filing Date: 2005-07-05
Classification: B21D

Abstract:
1. A method of hydroforming a tube having a round shape of a predetermined diameter and having a first length, into a hydroformed section at a predetermined location along its axis said tube having a first cross sectional area along its axis; and wherein said hydroformed section has a diameter less than said first length, and wherein the cross sectional area of the hydroformed section is less than said first cross sectional area, comprising the steps of: providing a first die member having a first cavity formed therein to correspond to the shape of said tube, said first die member having a second cavity formed therein in communication with said first cavity and wherein said second cavity is of the shape of the desired hydroformed section, providing a second die member to cooperate with said first die member having a third cavity formed therein to correspond to the shape of said tube and wherein said second die member is provided with a fourth cavity formed therein which is in communication with said third cavity, and wherein said fourth cavity has the shape of the desired hydroformed section providing a set of movable tube nests between said first and second die members loading said tube onto said tube nests moving said first and second die members from an open position to a closed position along said tube axis to engage said tube so that said second and fourth cavities are in registration, whilst simultaneously retracting said tube nests sealing the ends of said tube at said first and third cavities of said first and second die members performing a hydroforming operation on said tube by applying hydraulic pressure to said tube and thereby expanding said tube at said second and fourth cavities applying a predetermined axial force to said ends of said tube during said hydroforming operation opening said first and second die members by moving said first and second die members away from each other along said axis, after the hydroforming operation is complete and removing the hydroformed tube from said die members.