How much do you know about the "oil film strength" and "oil film thickness" of engine oil? Regarding the strength of the oil film, I read the information and it is defined as follows: The oil film has the ability to resist pressure without breaking, and to maintain sufficient oil film thickness to prevent direct contact with the friction surface. What is oil film strength? In terms of definition, the difference between oil film strength and oil film thickness is well stated. A parameter indicating the strength of the oil film is called "HTHS". This parameter is the apparent viscosity of the oil through the capillary viscosity test at 150°C, which is the dynamic viscosity. Because HTHS reflects the adhesion ability of the lubricating oil between the piston and the cylinder and between the shaft and the bearing bush, it is related to the oiliness agent or polar agent added to the lubricating oil. Many people call it "oil film strength". It is understood that the strength of the oil film is vivid and accurate. What is the oil film thickness? The oil film refers to the protective film formed by the oil in the engine, which will exist at all times. Since there is a film, there will be thickness. How is the thickness of the oil film measured? It can be simply understood as: high viscosity oil means thick oil film, thin oil means thin oil film. Why do you say that? Let's first look at the definition of viscosity. Viscosity is the internal resistance of the fluid, so the viscosity of lubricating oil is usually the thickness of the oil.
Therefore, when the engine is running, the engine can only be protected if the oil film is not broken. If the oil film is thin during operation and the oil film ruptures, the engine will wear out greatly. A key indicator involved here is the 100-degree kinematic viscosity. 100 degrees corresponds to the engine water temperature. This kinematic viscosity reflects the fluidity and flow resistance of the lubricating oil when the engine is running. The viscosity of a 100-degree lubricating oil is the kinematic viscosity, which indicates the thickness of the oil film that the lubricating oil can form. In addition, the corresponding viscosity index can be calculated based on the corresponding kinematic viscosity at 100°C and the kinematic viscosity at 40°C. In terms of oil film thickness, some people say that the thicker the oil, the better, so that the oil film is thick enough to better protect the engine. This is a misunderstanding in understanding. In fact, it is not good for the viscosity of engine oil to be too high or too low, and "appropriate viscosity" is the best. Because the viscosity of engine oil is too high or too low, it will have the following shortcomings: The viscosity is too high, the oil is thick, and the oil cannot be transported between the parts in a short time. Therefore, it will increase the wear and tear during startup. It will become difficult to start at low temperature, and the cleaning effect and cooling effect will be worse. Loss leads to increased fuel consumption. The viscosity is too low, the oil is thin, and it cannot be absorbed between the parts very effectively. Therefore, the lubricating, anti-wear and sealing functions are not well played, and the oil consumption also increases. Once the oil loses its viscosity, the oil film will also lose its ability to protect. If the engine oil contains a lot of water, the lubricity of the engine oil will deteriorate, the viscosity will decrease, and the anti-friction effect of the oil film of the engine oil will become worse. The deterioration of the engine oil is inevitable, and serious accidents may lead to more serious accidents, such as engines. Hold the axle and burn the tiles.
