1. HYDROFORMING
Presented by:
Byron Erath
Duane Ellsworth

2. OUTLINE: What is Hydroforming How and where is Hydroforming used
Materials used in Hydroforming processes
Design Considerations
Advantages/Disadvantages
Economics of Hydroforming
Websites and Links
Conclusion

3. HYDROFORMING
Hydroforming uses the force of water or hydraulic fluids to shape a single part.
There are two types of hydroforming:
1. Tube hydroforming
2. Sheet hydroforming

4. TUBE 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

5. SHEET HYDROFORMING 2 METHODS:
Sheet steel is forced into a female cavity by water under pressure from a pump or by press action
Sheet steel is deformed by a male punch, which acts against the fluid under pressure.
Note: Sheet hydroforming provides a work-hardening effect as the steel is forced against the blanks through fluid pressure.

6. APPLICATIONS Automotive industry Sanitary use Aerospace
Lighter, stiffer parts
Chevy SSR Frame

7. APPLICATIONS (CONT) 1. Body shell 2. Driving shaft
3. Assembled camshaft
4. Exhaust systems
5. Engine cooling system
6. Radiator frame
7. Safety requirements
8. Engine bearer
9. Integral member
10. Cross member
11. Frame structure parts
12. Axle elements

8. MATERIALS Steel (mild and harder steels) Stainless Steel
Aluminum alloys
Research continues to expand the capabilities of the hydroforming process

9. DESIGN CONSIDERATIONS
Hydroforming is generally defined as either low-pressure or high pressure.
The demarcation point is 83MPa
Constant pressure volumetric expansion
< 5% required to shape the part = Low pressure
> 5% (but < 25%) = High Pressure

10. DESIGN CONSIDERATIONS
Product
- Geometry, thickness distribution
- Dimensional accuracy/tolerances
- Surface finish
- Microstructure, mechanical and metallurgical
properties, hardness
Tool/Dies
-Geometry of tools
- Material hardness
- Surface conditions
- Stiffness and accuracy
Equipment
- Press capacity
- Speed/production rate
- Force/energy capabilities
- Rigidity and accuracy
Deformation zone Deformation mechanics, model used for analysis Metal flow, velocities, strain rates, strains (kinematics)
- Stresses (variation during deformation)
Work piece/Material
Flow stress as a function of strain, strain rate and microstructure
Workability as a function of strain, strain rate and microstructure
- Surface conditions
- Geometry of tubing ( outside diameter, tube wall thickness, roundness, properties of welding line, etc.)

11. ADVANTAGES Hydroforming draws material into the mold
Part consolidation
Weight reduction through more efficient section design and tailoring of the wall thickness
Improved structural strength and stiffness
Lower tooling cost due to fewer parts
Fewer secondary operations (no welding of sections required and holes may be punched during hydroforming)
Tight dimensional tolerances and low spring back
Reduced scrap

12. ADVANTAGES (CONT.)
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)

13. DISADVANTAGES Slow cycle time
Expensive equipment and lack of extensive knowledge base for process and tool design
Requires new welding techniques for assembly.

14. ECONOMICS

15. INFORMATION ON THE WEB
nsmwww.eng.ohio-state.edu/html/tube_hydroforming.html

16. CONCLUSION 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!

17. QUESTIONS???