PISTON

Introduction:  It is a disc or cylindrical part that slides to and fro in a hollow cylinder.

Definition:       

“In an internal-combustion engine it is forced to move by the expanding gases in the cylinder head and is attached by a pivoted connecting rod to a crankshaft or flywheel, thus converting reciprocating motion into rotation.”

Piston:

   

 

 

 

 


Fig: Piston

  • Pistons harness the energy of the power stroke and transfer the force toward the crankshaft.

 

Piston terminology:

  • Head or crown
  • Ring grooves
  • Ring lands
  • Oil return holes
  • Skirt
  • Pin hole
  • Pin boss
  • Pin offset                       

 

A piston of an internal combustion engine serves three functions:

  1. It forms a movable wall of the combustion chamber.
  2. It transmits turning force to the crankshaft via the connecting rod.
  3. It functions like a crosshead and transmits side thrust, which is due to the angularity of the connecting rods, to the cylinder walls.

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