Analysis and Troubleshooting of Cylinder Scuffing in a Diesel Engine

Introduction-The phenomenon of cylinder scuffing refers to damage caused by the interaction between the piston assembly and the cylinder liner of a diesel engine, resulting in scratches, burns, and seizures. Depending on the severity of the damage, these issues are typically classified as scoring, scuffing, and seizing.
Scuffing between the piston rings and the cylinder liner often occurs during the initial operation of a diesel engine. Once the break-in period is complete, the likelihood of scuffing significantly decreases.
If scuffing occurs, it can lead to poor cylinder sealing, causing air leakage, reduced engine power, and difficulties in starting the engine. In severe cases, it can result in damage to the piston, connecting rod, cylinder liner, and cylinder head. In the worst scenarios, it may damage the crankshaft and the entire engine, causing serious quality and safety incidents.
Therefore, it is essential to thoroughly analyze the causes of cylinder scuffing and perform comprehensive hazard inspections to prevent subsequent accidents.

Analysis of Causes and Contributing Factors for Main Engine Piston Ring Failures

Introduction - The primary function of piston rings is to seal the combustion chamber, ensuring that, when the piston reaches the top dead center, there is sufficient temperature and pressure in the chamber. This provides the necessary conditions for fuel combustion to occur rapidly and fully. However, the working conditions for the piston, piston rings, and cylinder liner — this "moving pair" — are very harsh, and their frictional losses account for 55–60% of the total frictional loss of power in the diesel engine. Therefore, the operational state of the piston rings plays a crucial role in the thoroughness of fuel combustion and the overall performance of the diesel engine. Effective management and maintenance of the piston rings are especially important for ensuring the engine operates efficiently.

Analysis of the Cause of Crankshaft Bearing Cap Failure in a Certain Type of Medium-Speed Diesel Engine and Improvement Measures

The connecting rod assembly transmits piston forces to the crankshaft. Bearing failures, caused by quality defects or fatigue, include cracking and wear. This study analyzes fractures in medium-speed diesel engines and suggests improvements.