Abstract
Piston-running behaviour remains one of the key determining factors in the reliability and time between overhauls for the diesel engine. This paper reports on some of development work with Wärtsilä large-bore, low-speed marine diesel engines. This has resulted in much improvement. The work led to better specifications for the cylinder liner surface morphology, standardisation on the chrome-ceramic coating for all piston rings, and improved distribution of cylinder lubricating oil on the surface of the cylinder liner. Shipboard testing dismissed the hypothesis that water droplets were reaching the cylinder liner surface. The overall results were confirmed by long-term trials on a fleet of ships.
