Engineering Explained on MSN

Piston rings & blowby - explained

How do piston rings work? What is blowby? Why are there three piston rings? What do each of the piston rings do? Typically there are three piston rings, and they serve three major purposes. They keep ...
In a conventional application, there are three rings per piston. The top ring is called the compression ring. Its purpose is to seal the combustion gas pressure, transfer heat from the piston to the ...