Results of the study of operating conditions in the cylinder and changes in the characteristics of diesel and gas diesel motor oils

Abstract This article discusses the results of a study of changes in the characteristics of M10G 2 oils during the operation of diesel engines and gas engines based on diesel engines. During engine operation, the oil in the lubrication system circulates under conditions of temperature difference. The thermal load of the engine depends on the engine boost. Thermal stress and temperature of hot gases intensively influence the oxidation of oil; this process occurs in the annular zone of the pistons. The operating conditions are harsh in the working surface of the cylinder in the piston stroke area, in this area the oil is subject to thermal decomposition and high oxidation intensity. When operating a diesel engine, compared to a gas-diesel engine, the main oil indicators such as viscosity, density, mechanical impurities, high- and low-temperature characteristics, chemical characteristics such as base number have lower limit values, and the oil service life can be considered 1.5 times higher when operating at gaseous fuel. The alkaline number in samples of used oils varies from 2.24 to 1.4, which indicates the emergency condition of the used oil. The results of analyzes of the alkaline number of the studied motor oils show that when the engine is running on gaseous fuel it decreased on average from 6.0 to 2.2 mg KOH/g, and when running on diesel fuel from 6.0 to 1.4 mg KOH/g. i.e. below the permissible level.