| 摘要 |
PROBLEM TO BE SOLVED: To provide a natural gas engine lubricating oil composition and a method for preventing or inhibiting exhaust valve seat recession in natural gas fueled internal combustion engines.SOLUTION: A natural gas engine lubricating oil composition is disclosed which comprises (a) a major amount of an oil of lubricating viscosity, (b) one or more phosphorus-containing anti-wear additives, (c) one or more ashless dispersants, (d) one or more alkaline earth metal salts of an alkyl-substituted hydroxyaromatic carboxylic acid, and (e) one or more antioxidants. The natural gas engine lubricating oil composition contains no more than about 0.03 mass percent of phosphorus based on the total mass of the natural gas engine lubricating oil composition. The natural gas engine lubricating oil composition is substantially free of any alkali metal-containing detergents.SELECTED DRAWING: Figure 1 |
