FUNCTIONS

Piston Rings must complete 3 principle functions in engines.

•  Seal off the combustion chamber from the crankcase 
•  Limit and control oil consumption
•  Transfer the heat absorbed by the piston in the combustion process to the cooled  cylinder walls.

 

 

           

 

TOP RING

This is referred to as the upper compression ring. This ring operates under the harshest conditions with respect to thermal and mechanical loading. Its job is to form a gas-tight barrier between the piston and cylinder wall in order to seal the combustion chamber. They also transfer the heat to the cooled cylinder walls like a bridge.

 

SECOND RING 

This is referred as the lower compression ring. One of its job is to work together with the top ring in order to seal the combustion chamber and transfer the heat to the cylinder walls. They also control oil consumption.

The scrapper or second compression ring behaves as both a compression ring and oil control ring.

 

OIL CONTROL RING

Oil Control Rings regulate and limit oil consumption. They scrape off excess lubricating oil from the cylinder walls and return it to the crankcase. They are designed to provide a thin oil film to ensure piston and ring lubrication.

Improper control results in cooking (carbon residues) or blue smoke in the exhaust gas and results excessive oil consumption.