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 place

Note: 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
and dimensional accuracy.
quality
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
Fewer

Design Flexibility.
Parts
Less Assembly
Less
Weight.
Lower
 Less
Tooling Costs.
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
increase
selection is broad and continues to
 Information
can be found everywhere!