Most of China’s gear oil production plants use single agents such as antioxidant, antirust agent, detergent dispersant, extreme pressure anti-wear agent, tackifier, oily agent and anti foaming agent to prepare gear oil. Although the method is flexible, it is not easy to ensure the performance of gear oil. For high-performance gear oil, a variety of additives should be added to the base oil. There are interactions among additives, and there are many effects among them, such as synergistic effect, additive effect and antagonistic effect. These additives in gear oil are called gear oil compound additives. Single agent additives are equivalent to raw materials, while composite additives are deeply processed. Major foreign oil companies are developing their own composite additives.

Advantages of gear oil compound additives

At present, some foreign companies producing gear oil additives mostly provide composite additives, and the additives are often multi-purpose, that is, changing the dosage of composite additives can prepare high-quality industrial gear oil and vehicle gear oil respectively. The use of composite additives has the following advantages: (1) the performance of additives is stable, which can simplify the blending operation and reduce the blending error; (2) Convenient storage, can avoid storing many kinds of single function additives and save costs; (3) For manufacturers, several additives can be sold together to facilitate transportation management.

Classification of compound additives for gear oil

There are two types of gear oil compound additives: one is single purpose gear oil compound additive, namely vehicle gear oil compound additive and industrial gear oil compound additive; The other is the general gear oil compound additive, that is, a compound additive is used to prepare vehicle gear oil at a higher dose and industrial gear oil at a lower dose. The performance requirements of vehicle gear oil and industrial gear oil are the same and different. Vehicle gear oil has high extreme pressure requirements, requires the use of highly active additives, and has strong copper corrosion. Therefore, the requirements for copper corrosion of vehicle gear oil are not as strict as that of industrial gear oil. In addition, vehicle gear oil does not require anti emulsification, and industrial gear oil requires Timken performance. The OK load of Timken test of heavy load industrial gear oil is not less than 267n, and many extreme pressure agents can not effectively improve the OK load. Industrial gear oil has strict requirements for copper corrosion. The copper corrosion of lubricating oil is actually a measure of the chemical activity of oil products. The restriction on copper corrosion actually limits the chemical activity of composite additives, which is contradictory to the requirements of high extreme pressure of vehicle gear oil. In order to meet the requirements of anti emulsification, anti emulsifier shall be used. Anti emulsifier is a surface active substance, which has strong adsorption capacity on the metal surface and will interfere with the adsorption of extreme pressure anti-wear agent on the metal surface.