1. 1
DESIGN AND DEVELOPMENT
OF STRETCH FORMING SETUP
JASPREET SINGH (10406EN013)
TEJ PRAKASH
(10406EN014)
SAHIL DEV
(10406EN016)
RAHUL WALTER
(10406EN017)

2. 2
WHAT IS FORMING?

Metal reshaping process

Uses mechanical deformation

No material removal

3. 3
CHARACTERISTICS OF FORMING PROCESS

Very high required loads and stresses

Large, heavy and expensive machinery

Used in mass production

4. 4
FORMING PROCESSES

Classified by differences in effective stresses

Compressive forming

Tensile forming

Combined compressive and tensile forming

Bending

Shearing

5. 5
COMPRESSIVE FORMING

Uniaxial or multiaxial compressive loading

Rolling

Extrusion

Die forming

Forging

Indenting

6. 6
TENSILE FORMING

Uniaxial or multiaxial tensile stress

Stretching

Expanding

Recessing

7. 7
COMBINED TENSILE AND COMPRESSIVE FORMING

Extrusion

Deep drawing

Spinning

Flange forming

Upset bulging

8. 8
BENDING AND SHEARING

Plastic deformation by bending / shearing load

9. 9
STRETCH FORMING

Forming by combined tensile and bending forces

Two types:



Simple stretch forming
Tangential stretch forming
For fabrication of contours having U-forms

10. 10
SIMPLE STRETCH FORMING

Fixed jaws

Minimum deformation under the die

Sheet expand

11. 11
TANGENTIAL STRETCH FORMING

Movable jaws

Plastic pre strain

Two steps:

Gripping by jaws

Forming by die

12. 12
VIDEO : TANGENTIAL STRETCH FORMING

13. 13
STRETCH FORMING EQUIPMENT IN INDIA

Two types:



Longitudinal
Transverse
Can be integrated to CNC

14. 14
GRIPPING MECHANISM

Two types:

Integral

Discrete

15. 15
PROJECT DESIGN

16. 16
BILL OF MATERIALS
Component × Quantity
Material
Mechanical Properties
1. Sheet ×1
AL-5052
UTS = 227.57 Mpa YS = 193.05MPa
2. Main Bolt × 1
C60(Carbon Steel)
UTS = 736 Mpa YS = 412 MPa
3. Rotating Holder×1
C60(Carbon Steel)
UTS = 736 Mpa YS = 412 MPa
4. Supporting Rod ×1
C60(Carbon Steel)
UTS = 736 Mpa YS = 412 MPa
5. U-Frame ×1
C60(Carbon Steel)
UTS = 736MPa YS = 412MPa
6. Stopper × 2
A-36 Mild Steel
UTS = 399.8 Mpa YS = 250.2 MPa
7. Mini Bolt × 2
A-36 Mild Steel
UTS = 399.8 Mpa YS = 250.2 MPa
8. Base ×1
A-36 Mild Steel
UTS = 399.8 Mpa YS = 250.2 MPa

17. 17
STRESS REQUIRED FOR FORMING


18. 18
NOTATIONS USED


19. 19
DESIGN OF BOLT


20. 20
CONTINUED…


21. 21
CONTINUED…


22. 22
DESIGN OF BASE


23. 23
DESING OF ROTATING HOLDER


24. 24
CONTINUED…


25. 25
CONTINUED…


26. 26
DESIGN OF SUPPORTING ROD


27. 27
CONTINUED…


28. 28
CONTINUED…


29. 29
DESIGN OF U-FRAME


30. 30
CONTINUED…


31. 31
WORKING OF VICE
Five main components

Sheet is fixed
Bolt is rotated
U-frame can rotate about the rod
Always tangential force on the sheet

32. 32
PLANS FOR 8TH SEMESTER

The next step involves designing a die for this specification of sheet so that
is does not get torn.

Fabrication of the components of vice.

Fabrication of die.

Testing of the setup.

33. 33
REFERENCES

Design data hand book by K.Mahadevan and K.Balveer Reddy.

Manufacturing technology by Kalpakjian.

En.wikipedia.org/wiki/sheet_metal.

Literature by training in aluminum application technology(TALAT).

www.sciencedirect.com/science/article/pii/S1003632609602570