Technology and Contribution of SUMEBore Cylinder Liner Surface Coatings on Lubricant Oil Consumption Reduction on an EMD710 Diesel Engine

Abstract

Rising fuel prices and more stringent requirements in the field of emissions such as nitrogen oxides, particulate matter and carbon dioxide are increasing the pressure on the engine manufacturers to utilize technologies that contribute to a reduction in these emissions. As a result, interest in cylinder surface coatings has risen considerably in the last three to four years, and particularly in the SUMEBore® coating solution from Sulzer Metco. Such coatings are applied by a powder-based atmospheric plasma spray process (APS). The APS method is very flexible and can also process materials to which wire-based methods do not have access, particularly high chromium containing steels, metal matrix composites (MMCs) and pure ceramics. The compositions can be tailored to the specific challenges in an engine, e.g. excessive abrasive wear, scuffing or corrosion caused by adulterated fuels and/or high exhaust gas recirculation rates (EGR). Over the past four to five years cylinder liner surfaces from trucks, diesel locomotives, marine and gas engines, for power generation and gas compression have been coated with such materials. These engines have been tested successfully. Most of the tested engines achieved significant reductions of lubrication oil consumption (LOC), sometimes in excess of 75%, reduced fuel consumption, very low wear rates and corrosion resistance on the liner surfaces. As an example the paper will highlight the coating of cylinder surfaces in a 4,000 hp EMD 16-710G3 locomotive diesel engine. Details of the application of a corrosion resistant MMC will be shown, together with results obtained with the Da Vinci DALOC measurement technique in an engine test where the lubricant oil consumption was accurately quantified at 4 steady-state operating conditions typical of North American freight locomotive and which clearly showed the significant contribution of the liner ID coating to reduction of lubricant oil consumption (LOC).