HYDROFORMINGHYDROFORMING

Presented by:

Byron Erath

Duane Ellsworth

OUTLINE: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

HYDROFORMINGHYDROFORMING

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

TUBE HYDROFORMINGTUBE 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

Outer tool part

Tube

Inner tool part

Section A - A

Upper tool partnot shown

SHEET HYDROFORMINGSHEET 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.

APPLICATIONSAPPLICATIONS

Automotive industry

Sanitary use

Aerospace– Lighter, stiffer parts

Chevy SSR Frame

APPLICATIONS (CONT)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

MATERIALSMATERIALS

Steel (mild and harder steels)Stainless SteelAluminum alloysResearch continues to expand the

capabilities of the hydroforming process

DESIGN CONSIDERATIONSDESIGN 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

DESIGN CONSIDERATIONSDESIGN 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

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.)

Deformation zone - Deformation mechanics, model used for analysis - Metal flow, velocities, strain rates, strains (kinematics)

- Stresses (variation during

deformation)

ADVANTAGESADVANTAGES

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

ADVANTAGES (CONT.)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)

DISADVANTAGESDISADVANTAGES

Slow cycle time

Expensive equipment and lack of extensive knowledge base for process and tool design

Requires new welding techniques for assembly.

ECONOMICSECONOMICS

INFORMATION ON THE WEBINFORMATION ON THE WEB

www.hydroforming.net www.vari-form.com www.hdt-gti.com www.revindustries.com www.autosteel.org www.schuler-hydroforming.de www.egr.msu.edu/~aenader nsmwww.eng.ohio-state.edu/html/tube_hydroforming.html

CONCLUSIONCONCLUSION

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!

QUESTIONS???QUESTIONS???