OPERATIONAL EVALUATION OF PISTON-RINGS-CYLINDER LINER ASSEMBLY WEAR IN HIGH POWER MARINE DIESEL ENGINES

Abstract

This paper presents an operational evaluation of piston-piston rings-cylinder liner (PRC) assembly wear in marine diesel engines of high power. It is based on visual inspection through cylinder liner scavenge ports. Clearance measurements of piston rings in piston grooves and piston ring gap measurements were used to evaluate the extent of wear of the PRC assembly. Moreover, it is shown that piston ring gap measurements can be used as a reference parameter in wear trend analysis to predict the length of time periods between overhauls (TBO). Furthermore, it has been shown that controlling the wear of chromium (protective) layers of piston ring working surfaces by measuring their thickness with induction and eddy current methods is highly useful. They were accepted as a source of information on PRC lubrication correctness and as a symptom of its technical condition. Factors indicating the necessity of an overhaul and introducing operational methods of improving working conditions between the tribological pair – liner and piston rings have been determined.