Hydroforming - TubesMEE 3024

Hydroforming

Hydroforming Concept

BenefitsIncreased strength to weight ratiosMultiple cross – section reshaping or section modules increaseImproved stiffness torsion and bending rigidlyImprovement in noise, harshness, vibration (NHV) FactorIncorporation of hole punching, slot making, embosses during hydro forming process.Reduction in number of manufacturing stages, hence reduced tooling costsReduction in welding, hence distortion and subsequent heat treatmentGreatly reduced springback due to stretching

Hole Piercing Accuracy

Springback Reduction

No springback, only slight change in length

Maximum springback due to tension and compression

Minimal springback due to tension and no compression

NP NPTake MomentsAround NP

Hydroforming – Process Defects

Hydroforming System

Hydroforming Tooling

Tube Bending Made Preform

Hydroforming Process – High Pressure

• Tube Perimeter and diameter < Die Perimeter and width

• Die Closes completely under no pressure

• Tube is pressurized to fill remaining open cavities in the die

• Friction from die/tube contact prevents sliding and leads to localized thinning in corners

• More complicated geometry possible

Hydroforming Process – Low Pressure

• Tube Perimeter and Dia. ~ Die Perimeter and Width

• Die Closes partially under no pressure

• Tube is pressurized to and die completes travel

• Pressure completes “fill” with no localized thinning in corners as perimeters approximately same

• Less complicated cross-sectional geometry can be formed