Gear oil is a higher viscosity lubricating oil designed to protect transmission power parts, usually accompanied by a strong sulfur odor. Vehicle gear oil uses two methods, performance classification and viscosity classification. At present, countries around the world widely use the American Petroleum Institute (API) performance classification and the US military gear oil specification standards. Most of the manual transmissions of lubricants and the difference is hypoid gear oil. These contain extreme pressure (EP) additives and anti-wear additives to cope with the action of sliding hypoid bevel gears. Vehicle gear oil
Vehicle gear oil
When the gear oil works, the working surface of the gear changes continuously and the temperature does not increase sharply, so its working temperature is generally 10 ℃ ~ 80 ℃; secondly, the gear oil is subjected to high pressure. When the gear is transmitting, the unit pressure of the meshing part between the teeth is as high as (196 ~ 245) × 10kPa, while the unit pressure of the hyperbolic gear is as high as (294 ~ 392) × 10kPa. In addition, the gear oil works under conditions of large speed changes and many revolutions, so the gear oil is easily squeezed out of the gap between the teeth, resulting in semi-liquid friction.
The main requirement for gear oil is that a continuous and tough oil film can be formed on the contact surface between the teeth, that is, it has high oiliness, and maintains a tough boundary oil layer between the transmission parts to ensure the transmission parts wear. Small and prevent its abrasion; In addition, the gear oil should also have good viscosity-temperature characteristics to ensure that the friction loss of the power transmission mechanism is small, improve transmission efficiency, and ensure that the car is easy to start (especially in winter).