Cylinder liners of both 4-stroke and 2-stroke engines show signs of wear and tear after extended use, regardless of the latest advances in lubricating oil and liner casting technologies. What's not quite so obvious is that when doing the consequent engine overhauls or engine repairs that involve cylinders, it is predictable that the liners will have to be deglazed and crosshatched. For cylinder deglazing jobs (plateauing as well) one industry standard tool is the compact, portable ball hone from Brush Research Manufacturing (BRM), who recently announced that its Flex-Hone® tool was available for ‘big bore’ marine diesel engines up to 40-inches in diameter.
'Big Bore' Cylinder Liner: Photo courtesy of Bright Hub Engineering
When a cylinder liner comes out of the factory, it will have a slight cross-hatch pattern honed into its surface, an increased roughness to help the liner surface to retain the lubricating oil needed to provide an evenly distributed oil film between t... [More]
Large bore diesel engine piston ring and cylinder liner design was ratcheted up more than a few notches on the efficiency scale by research that flowed from the (now concluded) European Union sponsored HERCULES project. The piston ring itself might seem a fairly inconsequential part of the whole engine, yet commercially important length of Time Between Overhauls (TBO) is largely determined by piston running behaviour and its effects on the wear of piston rings and cylinder liners. Recognising this fact, one sector of the interrelated study was devoted to an investigation into how engine friction might be reduced, but first it may be helpful to reprise HERCULES.The HERCULES Project The project title word HERCULES is itself an acronym (at a far stretch) signifying ‘High Efficiency R&D on Combustion with Ultra-low Emissions for Ships’, which pithily defines the scope of the three-and-a-half year project led by MAN Diesel SE and Wärtsilä Corporation with a t... [More]