1. The role of piston ring
Piston ring is an important part of Marine diesel engine, the main functions include:

Seal: Prevents combustion chamber gas from leaking into the crankcase and maintains compression pressure.

Heat transfer: Conducts piston heat to the cylinder wall to aid cooling.

Oil control: Adjust the amount of lubricating oil on the cylinder wall to prevent too much oil from entering the combustion chamber.

Support: Reduces friction and wear between the piston and the cylinder wall.

2. Type of piston ring
Gas ring (compression ring) : used to seal the combustion chamber gas to prevent leakage.

Oil ring: Controls the lubricating oil on the cylinder wall to prevent excess oil from entering the combustion chamber.

3. Materials and manufacturing
Materials: Commonly used materials include cast iron, alloy cast iron, steel, etc., need to have high wear resistance, heat resistance and strength.

Manufacturing process: Precision casting, heat treatment and surface treatment (such as chrome plating, nitriding) are usually used to improve performance.