Post on 25-Jun-2015
A Seminar Report
On
HYDROFORMING
Prepared by :-Patel Mehul.APatel Jay
Guided By ;-
D.H.Patel
OUTLINE:
• What is Hydroforming• Types of hydroforming• Application• Design Considerations• Advantages/Disadvantages• Economics of Hydroforming• Reference Websites and Links• Conclusion
HYDROFORMING
Hydroforming is a manufacturing process where liquid pressure is used to form complex shapes.
There are two types of hydroforming:
1) Tube hydroforming 2) Sheet hydroforming
TUBE HYDROFORMING
Outer tool part
Tube
Inner tool part
Section A - A
Upper tool partnot shown
• 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.
Tube Hydroforminga b
c d
FaxialFaxial
P
e f
SHEET HYDROFORMING
• 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.
APPLICATIONS
• Automotive industry
• Sanitary use
• Aerospace– Lighter, stiffer parts
Chevy SSR Frame
APPLICATIONS (CONT)1. Body shell2. Driving shaft3. Assembled camshaft4. Exhaust systems5. Engine cooling system6. Radiator frame7. Safety requirements8. Engine bearer9. Integral member10. Cross member11. Frame structure parts12. Axle elements
MATERIALS
• Steel (mild and harder steels)
• Stainless Steel
• Aluminum alloys
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
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
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)
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
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)
DISADVANTAGES
• Slow cycle time
• Expensive equipment and lack of extensive knowledge base for process and tool design
• Requires new welding techniques for assembly.
ECONOMICS
INFORMATION 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
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!