A special type of die forming using a high pressure Hydraulic fluid to press room temperature working material into a die
Discovered by HOLMSTROEM, MARTIN
There are three types of hydroforming:
1. Tube hydroforming
2. Sheet hydroforming
3. Explosive hydroforming
Used when a complex shape is needed
A section of cold-rolled steel tubing is placed in a closed die set
A pressurized fluid is introduced into the ends of the
tube
The tube is reshaped to the confine of the cavity
Involves forming of sheets with application of fluid pressure
Metal blank is subjected to hydraulic counter pressure generated by punchs
Required deformation takes placeNote: Sheet hydroforming provides a work-hardening effect as the
steel is forced against the blanks through fluid pressure.
Used for large parts Generates the forming pressure by a
simple explosion above the part which is immersed in water.
1. Outer skin with its extreme demand of surface quality and dimensional accuracy.
2. Longer outer skin parts for passenger cars, utility vehicles
3. Low capital cost. Fewer and simpler dies.
4. Better NHV (noise, vibration and harshness )factors.
5. Reduction in weight.
7. High process capability.
8. Reduction in cost of component.
Steel (mild and harder steels) Stainless Steel Aluminum alloys Research continues to expand the
capabilities of the hydroforming process
Extraordinary Design Flexibility.
Fewer Parts
Less Assembly
Less Weight.
Lower Tooling Costs.
Less Post-Processing
Greater Integrity (pressure flows the metal into
corners for greater precision rather than
streching)
Results compared to conventional steel body structure:
50% less weight 45% less parts (less tools, less assembly) 45% less welding seams Tighter tolerances
Volvo Hydroformed Structure concept in Aluminum, (Schuler Hydroforming 1998)
Slow cycle time
Expensive equipment and lack of extensive knowledge base for process and tool design
Requires new welding techniques for assembly.
Hydroforming is an innovative forming process
Hydroforming is becoming more popular (ie.automotive and aerospace industries)
The advantages outweigh the limitations
Material selection is broad and continues to increase
Information can be found everywhere!