Federal-Mogul introduces eWave piston ring to reduce oil consumption and extend liner life on typical two-stroke diesel engines.
Federal-Mogul Powertrain, a division of Federal-Mogul Holdings Corporation, has developed a new piston ring for two-stroke diesel engines that reduces oil consumption and thus the emissions by reducing the quantity of cylinder lubricant used.
- The shape of the piston ring is of new design such that it has a waved groove pattern.
- This waved groove increases the surface area and thereby distributes the cylinder lube oil more evenly throughout the cylinder liner bore.
- Testing the new design piston rings since 2013, clocking up close to 8,000 running hours has shown improvements in the area of wear resistance and reduced frictional resistance.
- The vessel has noticed a significant reduction in cylinder lube oil by 20% when compared to a conventional piston ring design.
- The eWAVE piston ring creates a circumferential pressure difference that generates controlled oil flow around the bore as the piston reciprocates, improving the uniformity of the oil film.
- Conventional Engines: Lube oil is fed differently into two-stroke engines as opposed to four-strokes, yet conventional piston rings are designed in a similar way for both types of machine. In conventional four stroke engines, there is a flow of oil from the crankcase around the entire circumference of the ring. However, in two-stroke engines the lube oil is sprayed against the cylinder liner in proportion to the engine load. This feed oil is not uniformly distributed on the cylinder wall.
- As two-stroke lube injection does not always ensure a uniform film, surplus oil is used to ensure protection – much of it going straight out as exhaust gas. The eWave’s shape creates a pressure difference that controls the oil flow around the bore and improves film uniformity.
“eWave is the first ring that disperses oil around the bore in a homogeneous layer, protecting against local oil film breakdown, improving the sealing of combustion gases, reducing wear and ensuring more uniform liner temperatures. This means the amount of oil injected into the cylinder can be greatly reduced and, because two-stroke engines expel their lubricant in the exhaust, less oil means lower carbon emissions as well as reduced operating costs”, says Richard Mittler, senior expert manager, analysis and product development, technology, rings & liners.
Source: Federal-Mogul – Investors