RING PACK TO HDD ENGINES FOCUSED ON LOW FUEL CONSUMPTION Rafael Antonio Bruno 1 , Andre Ferrarese 1 , Daniel Lopez 2 and Eduardo Nocera 1 1 MAHLE Metal Leve S.A. 2 MAHLE GmbH E-mails: rafael.bruno@br.mahle.com , andre.ferrarese@br.mahle.com , daniel.lopez@mahle.com , eduardo.nocera@br.mahle.com , ABSTRACT Low fuel consumption is a target for all engine developers. This demand is aligned with many others: high power output, improved mechanical efficiency, low emissions etc. These demands are linked to economic, politic and environmental aspects and they all come to a key-demand: low friction components. Low friction concept is based not only in materials with low friction coefficient. It is also given through low friction designs. This work will present and discuss the possibilities of doing it for a piston ring pack applied in a Heavy Duty Diesel (HDD) engine without jeopardizing the performance on blow-by and lube oil consumption. Basically the sum of tangential force of the ring pack divided by the bore diameter is a factor able to express the friction potential of the ring pack. Today engines on Euro 4 and Euro 5 versions present this value between 0.9 and 1.1 N/mm. The use of low friction concepts like low width, materials with low friction coefficient and optimized oil ring design enables to reach the level of 0.5 and 0.6 N/mm, i.e. almost 50% of potential friction reduction. Fuel consumption in a preliminary dyno test showed around 0.4% reduction using optimized ring pack compared to Euro 5. This paper presents the main achievements on low friction ring pack on HDD engines using rig and dynamometer tests. It is used and presented results on engines focused on Euro 5 and Euro 6 versions. 1. INTRODUCTION Global environmental concerns are driving internal combustion engine designs to higher efficiency. New legislations are setting up milestones to reach commercial vehicle emission goals and limit NOx and particulate material emission levels to achieve more environmentally friendly engines. Latest developments are heavily focused on the reduction of pollutant emissions through the improvement of the combustion efficiency or the introduction of after treatment systems. However, the using of low friction components as a means to reach fuel economy and, consequently low emission targets, seems to be not so explored so far. But such application could represent a significant potential. Figure 1 shows an overview of the legislations concerning NOx and Particulated Material (PM) and how it is spread on several regions. Meeting these emission targets will require the introduction of new Power Cell Unit (PCU) technologies and a more detailed system understanding. Low friction Power Cylinder DESTROY THIS DOCUMENT AFTER ITS USE. THE ORIGINAL IS IN THE MAHLE LIBRARY DESTRUA ESTE DOCUMENTO APÓS SEU USO. O ORIGINAL ENCONTRA-SE NO MAHLE LIBRARY