SEMINAR ONDESIGN AND MANUFACTURING OF

BEARING CUP

L. DINESH REDDY 07241A0304

R. SHIVA KUMAR 07241A0319

B. THARUN VISHNU 07241A0323

INTRODUCTIONINTRODUCTIONINTRODUCTIONINTRODUCTIONPress ToolPress Tool is a set of plates with a relief, or depth-based design, in them. The metal is placed between the plates, and the plates are pressed up against each other, and the plates are pressed up against each other, deforming the metal in the desired fashion.

There are different types of press machines:Some of them are:-C ( f d & b k l bl )C-type( fixed type & open back inclinable press)Single action straight side pressTypical Hydraulic press Typical Hydraulic press

DIEDIEDIEDIE

A Die is an assemblage of parts used for producing different sheet metal components.

The Die is also called press tool as the dies are used on different types of presses based on the cutting forces required for the component.

I h bl k d d d d In this project a blanking die, piercing die, drawing die is produced for production of bearing cap used to protect from dust from bearings of a ceiling fan.g g

There are different types of die to press relationships:-

Press Shut heightCapacity of pressCapacity of pressFeed Height

Materials used for making die sets:-

HCHC Mild steel

Bearing cupBearing cupBearing cupBearing cup

Our Project lays emphasis on the design of sheet metal dies for production of bearing cup used to protect the b i b ti th d t t t Th i bearings by preventing the dust to enter .The main objective of the our project is to design a bearing cup by the following operations:-

Blanking OperationPiercing OperationDrawing Operation

3D3D--diagram of bearing cupdiagram of bearing cup3D3D diagram of bearing cupdiagram of bearing cup

3D view of bearing cup3D view of bearing cup3D view of bearing cup3D view of bearing cup

Blanking operationBlanking operationBlanking operationBlanking operation

Blanking: Blanking is used to produce blanks of desired contour and size by b a s o es e co tou a s e by cutting them out of the stock strip. Blank is the desired ‘piece part’ made by p p yBlanking operation.

Remaining after blanking is called as ‘scrap’scrap

Inverted top view of blanking and Inverted top view of blanking and piercing die platepiercing die plate

3D diagram in 3D diagram in catiacatia3D diagram in 3D diagram in catiacatia

Piercing operationPiercing operationPiercing operationPiercing operation

Piercing: This operation consists of simple hole punching. It differs from s p e o e pu c g. t e s o blanking in that the punching (or material cut from stock) is the scrap and the strip ) p pis the work piece.Piercing is nearly always accompanied by Piercing is nearly always accompanied by a blanking operation before, after or at the same timethe same time.

Top view punch and stripper plateTop view punch and stripper plateTop view punch and stripper plateTop view punch and stripper plate

3D diagram in 3D diagram in catiacatia3D diagram in 3D diagram in catiacatia

Drawing operationDrawing operationDrawing operationDrawing operation

A flat blank is formed into a cup by p yforcing a punch against the center portion of a blank that rests on the die ring. g

Top view of drawing dieTop view of drawing dieTop view of drawing dieTop view of drawing die

3D diagram in 3D diagram in catiacatia3D diagram in 3D diagram in catiacatia

Die placed in open back Die placed in open back inclined pressinclined press

Strip layoutStrip layoutStrip layoutStrip layout

Strip layout plays an important role p y p y pespecially in the case of the design of the press tool. p

Strip decides the economic utilization of Strip decides the economic utilization of the work piece and helps in the decrease of cost of the job and reduction in the of cost of the job and reduction in the production time by increasing the number of componentsof components.

Working Working Working Working

Design calculationsDesign calculationsDesign calculationsDesign calculationsBlanking calculations :

Shearing force for blanking operation:Sh f F (K*L*T*S)/1000 TONSShear force F= (K*L*T*S)/1000 TONSK =1.2 for normal clearance L = perimeter of the blank = 188 4 mmL = perimeter of the blank = 188.4 mmT =thickness of the stock strip = 1 mmS =shearing strength of mild steel = 21 kg/sq.mmg g g qShearing force = (1.2*188.4*1*21)/1000 TONS

= 4.7 TONS

Piercing Calculations:

Shearing force for piercing operation:

Shear force F= (K*L*T*S)/1000 TONSShear force F (K L T S)/1000 TONS

K =1.2 for normal clearance

L = perimeter of the hole = 78.5 mm

T =thickness of the stock strip = 1 mm

S =shearing strength of mild steel = 21 kg/sq.mmS shearing strength of mild steel 21 kg/sq.mm

Shearing force = (1.2*78.5*1*21)/1000 TONS

= 2.6 TONS

Drawing calculations :

Shearing force for drawing operation:

Shear force F= (K*L*T*S)/1000 TONS

K =1 2 for normal clearance K 1.2 for normal clearance

L = perimeter of the hole = 78.5 mm

T =thickness of the stock strip = 1 mm

S =shearing strength of mild steel = 21 kg/sq.mm

Shearing force = (1 2*78 5*1*21)/1000 TONSShearing force (1.2 78.5 1 21)/1000 TONS

= 1.2 TONS

Total tool calculationsTotal tool calculationsTotal tool calculationsTotal tool calculations

Total force required for the compound q ptool=

shearing force for blanking operation + s ea g o ce o b a g ope at o shearing force for piercing operation + total load required for drawing operationq g p

=4 7+2 5+1 2=8 4tons=4.7+2.5+1.2=8.4tons

Cost analysisCost analysisCost analysisCost analysisCOMPUND DIE Manufacturing time in hours Manufacturing cost per hour Amount in Rs

Conventional milling 12 100 1200

Grinding 10 100 1000

Jig Boring, Drilling 10 100 1000and tapping

• CNC wire cut 5 320 1600

Lathe turning 6 100 600

Cylindrical Grinding 3 200 600

Total cost 6000Total cost 6000

Other costsOther costsOther costsOther costs

Allen screw, dowel pins, high tension rubber material are purchased from ubbe ate a a e pu c ase o markets, including the raw material for making the die and the heat treatment of gthe material has been charged = Rs 3000Total cost of the compound die = Total cost of the compound die

6000 + 3000R 9000 =Rs.9000

Conclusions Conclusions Conclusions Conclusions 1) The Bearing cup can be manufactured in 3 operations namely blanking operation drawing operation piercing namely blanking operation, drawing operation, piercing operation.

2) The Compound die is used in the batch operation of 2) The Compound die is used in the batch operation of 6000 units of bearing cups.

3) Th it t f th b i i R 33) The unit cost of the bearing cup is Rs 3.

4) The life of the compound die can be increased by h h l l k h d h dmachining the vital parts like punch and the die.

5) The impact plate which is placed between the bottom ) p p pbolster and punch holder is replaced if necessary to improve the die life.

References References References References

Tool design by Cyril Donaldson, g y yDonaldson Mn.Fundamentals of tool design by David u a e ta s o too es g by av Spitler,John G.Nee,David Alkire Smith,Society of Manufacturing Engineers., y g gFundamentals of press working by David Alkire SmithAlkire Smith.