Federal-Mogul piston ring advances

Two-stroke engines, which can suffer from uneven distribution of lubricating oil on the cylinder bore surface, can benefit from Federal-Mogul Powertrain’s eWAVE technology. The geometry of the new piston ring creates a circumferential pressure difference that generates controlled oil flow around the bore as the piston reciprocates providing greater protection.

Meanwhile the company’s galvanic coatings, such as GDC (chrome diamond coating) and CKS (chrome ceramic coating) help to reduce the wear rate of both ring and liner can be applied in different thicknesses, to match the life required.

Gian Maria Olivetti, chief technology officer, Federal-Mogul Powertrain, said: “LBEs are in use globally in the marine, power generation, railway, construction and defence industries and the wide range of engine types and applications makes ring design extremely challenging. With our exceptional breadth of technological expertise, Federal-Mogul Powertrain is ideally positioned to deliver the solutions that customers demand.”

Ring design for LBEs is increasingly driven by the desire to minimise environmental impact through reduced oil consumption and pressure to cut operating costs by improving fuel economy and extending TBO (time between overhauls). Federal-Mogul Powertrain satisfies these demands with ring geometries that optimise contact conditions with the cylinder bore, and through the use of wear-resistant materials and coatings that promote longer life. It has been developing negative ovality piston rings, which reduce radial pressure at the ring gap and prevent cylinder and ring damage, for more than 40 years.