What Is The Viscosity Of Engine Oil?
Temperature has a great influence on the viscosity of the oil. The temperature rises and the viscosity decreases; the temperature decreases and the viscosity increases. Lubricating oil, which changes its viscosity due to temperature rise and fall, is called viscosity temperature. Good viscosity temperature means that the viscosity of the oil changes little with temperature.
The operating temperatures of the various lubrication points that the engine oil is exposed to vary greatly. Therefore, it is required that the engine lubricating oil can maintain a certain viscosity when working at high temperature to form an oil film of sufficient thickness to ensure the lubricating effect; while at low temperature, the viscosity does not become too large to maintain a certain fluidity. It makes the engine easy to start at low temperatures and reduces the wear of parts.
Adding a viscosity index improver to the base oil can increase the viscosity of the oil. The engine oil that can meet the requirements of low-temperature use at the same time is called multi-intensity engine lubricating oil, commonly known as thickening machine oil.
The evaluation index of the viscosity of engine lubricating oil is the viscosity index.