SUMEBore - The Coating Solution to Protect Cylinder Liner Surfaces 2012-01-1992

Rising fuel prices and more stringent requirements in the field of the vehicle emissions such as nitrogen oxides, particulate matter and carbon dioxide will increase the pressure on the engine manufacturers to utilize technologies which contribute to a reduction in these emissions. As a result, interest in cylinder surface coatings has increased considerably in the last few years, also in the SUMEBore® coating solution from Sulzer Metco.

SUMEBore coatings are applied by a powder-based air plasma spraying (APS) process. Such an APS process is very flexible and can also process materials to which wire-based methods do not have any access, particularly metal matrix composites and pure ceramics. The compositions can be tailored to the specific challenges in an engine, e.g., excessive abrasive wear, scuffing, corrosion caused by adulterated fuel or high exhaust gas recirculation (EGR) rates, etc. Over the past several years cylinder liner running surfaces from trucks, diesel locomotives, marine and gas engines, for power generation and gas compression have been coated with such APS materials and engines have been tested successfully. Most of the tested engines achieved significant reductions in lubricant oil consumption (LOC), sometimes in excess of 70%, reduced fuel consumption, very low wear rates and good corrosion resistance on the liner surfaces. Results are presented from a full size test on an EMD-710G3A locomotive engine, which was performed in collaboration with GE Transportation at the Southwest Research Institute (SwRI) in San Antonio, TX.

This APS coating solution has already been commercialized in various markets; it has proven to be suitable for mass production on both new engine blocks and liners, and for repair of worn-out parts. Such coatings will continue to play an important role when it comes to reductions of emissions from internal combustion engines.