The document discusses the design considerations for pistons. Pistons must contain cylinder pressure, transmit combustion pressure to the connecting rod, and provide a place for oil control rings. They must be rigid enough to withstand tremendous pressures and forces but also ductile enough to absorb pressure peaks without shattering. Common piston materials include cast aluminum, forged aluminum, and hypereutectic alloys. The presentation goes on to discuss piston construction elements like piston rings, the piston barrel, skirt, and pin as well as design aspects like piston pin offset.

1. PRESENTATION
ON
DESIGN OF PISTONS
Prepaded by :
Mehul Gohel
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2. PISTON DESIGN CONSIDERATIONS
 Pistons must:
 Contain cylinder pressure
 Transmit the pressure created by combustion to force
on the connecting rod
 Provide a place for oil control and compression rings
to be located
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3. PISTON DESIGN CONSIDERATIONS
 Pistons must:
 Be rigid enough to not deform under the tremendous
pressures and forces encountered
 Be ductile enough to absorb pressure peaks and not
shatter
 Retain the proper shape under the extreme
temperatures encountered
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4. PISTON CONSTRUCTION
 Materials
 Cast iron (used in very old engines)
 Cast aluminum (most common)
 Forged aluminum
 Hypereutectic alloys (high silicon content aluminum)
 Carbon Graphite (being tested)
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5. PISTON CONSTRUCTION
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6. PISTON CONSTRUCTION
 Piston design
 Piston rings
 Barrel of piston
 Piston skirt
 Piston pin
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7. PISTON DESIGN

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8. DESIGN OF PISTON

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9. PISTON RINGS

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10. BARREL OF PISTON

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11. MAJOR/MINOR THRUST
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12. PISTON SKIRT

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13. PISTON PIN
 Piston Pin Offset
 The piston pin is offset towards the major thrust side
of the piston to reduce piston wear, and piston noise
 The major thrust side is the side that is loaded during
the power event
 The minor thrust side is the side loaded during the
compression event
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14. PISTON PIN

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15. PISTON PIN

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