Federal-Mogul Powertrain has been selected to supply the pistons, pins and ring packs for the quad-turbo diesel engine that will power the 2017 BMW 750d and 750Ld xDrive models. The new 3.0-liter six-cylinder diesel develops 294kW/400hp and peak torque of 760Nm/560lb-ft.
Tasked with delivering a robust solution for low levels of blow-by and oil consumption over the entire life of the vehicle, Federal-Mogul Powertrain’s piston and ring engineers worked closely with BMW engineers throughout the development program. The high level of co-operation enabled the engine to incorporate a number of advanced Federal-Mogul Powertrain piston and ring technologies.
Said Gian Maria Olivetti, CTO, Federal-Mogul Powertrain, “Meeting the requirements for this engine was very demanding. Having four turbochargers tends to increase blow-by, which is also influenced by the use of direct bore coating rather than cylinder liners, resulting in slightly greater thermal expansion. Additionally, the higher peak cylinder pressures and specific power mean that the loads on both piston and ring pack are increased.”
Federal-Mogul Powertrain met all the targets by combining a number of its leading technologies with a state-of-the-art product traceability system. The aluminum piston uses DuraBowl remelting to refine the micro-structure of the bowl rim and increase its strength and advanced 2D ultrasonic inspection ensures zero defects. A high cooling gallery location reduces bowl rim stresses through optimum cooling and an EcoTough skirt coating reduces friction and wear, improving scuff resistance.
The ring pack was developed with the support of Federal-Mogul PRiME 3D simulation software to meet the stringent blow-by and oil consumption targets and incorporates a number of technologies that are proprietary to Federal-Mogul Powertrain.
The first compression ring carries a Goetze Diamond Coating (GDC) to optimize friction and wear; the oil control ring uses the LKZ profile, which actively pulls oil away from the combustion chamber for low oil consumption throughout the life of the engine.
The traceability of every individual compression ring, rather than just each batch, is ensured by using DMC (data matrix codes) to record function-related features following 100% inspection, giving complete control of the entire production.
September 14, 2016