Method of forming a tubular member with separate flange

A method of forming an elongated vehicle body structural component having a closed portion and an open flange, comprising the steps of,

• dividing said flange shape into constituent, substantially planar sections,
• establishing a parting plane relative to which a cross section of said flange taken perpendicular to said parting plane has minimal reverse curvature relative to said parting plane,
• establishing a weld line that is substantially parallel to parting plane,
• providing a first die movable along said parting plane and having a center cavity corresponding in shape to the lower surface of said tubular portion and a shoulder section corresponding in shape to the lower surface of said flange,
• providing a second die movable along said parting plane and having a center cavity corresponding in shape to the upper surface of said tubular portion and a shoulder section corresponding in shape the upper surface of said flange,
• providing a tubular blank having a closed cross section with a circumferential measure substantially equal to said tubular portion,
• providing a substantially planar blank having a surface area substantially equal to said open flange,
• securing said planar blank to said tubular blank so as to provide a compound blank,
• positioning said compound blank between said dies,
• progressively closing said dies around said compound blank so as to simultaneously stamp said planar blank between said die shoulders to produce said flange while deforming said tubular blank between said die cavities to partially form said tubular portion, and,
• pressurizing said tubular blank so as to completely form said tubular portion between said cavities.

A method of forming an elongated vehicle body structural component having a closed portion and an open flange, comprising the steps of,

• dividing said flange shape into constituent, substantially planar sections,
• establishing a parting plane relative to which a cross section of said flange taken perpendicular to said parting plane has minimal reverse curvature relative to said parting plane,
• establishing a weld line that is substantially parallel to parting plane and which substantially bifurcates said flange,
• providing a first die movable along said parting plane and having a center cavity corresponding in shape to the lower surface of said tubular portion and a shoulder section corresponding in shape to the lower surface of said flange,
• providing a second die movable along said parting plane and having a center cavity corresponding in shape to the upper surface of said tubular portion and a shoulder section corresponding in shape the upper surface of said flange,
• providing a tubular blank having a closed cross section with a circumferential measure substantially equal to said tubular portion,
• providing a substantially planar blank having a surface area substantially equal to said open flange,
• securing said planar blank to said tubular blank so as to provide a compound blank,
• positioning said compound blank between said dies,
• progressively closing said dies around said compound blank so as to simultaneously stamp said planar blank between said die shoulders to produce said flange while deforming said tubular blank between said die cavities to partially form said tubular portion, and,
• pressurizing said tubular blank so as to completely form said tubular portion between said cavities.