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Lube base oil has the basic characteristics of lubricants and some performance, but only rely on the processing technology to improve the lube, and can not produce a variety of properties are in line with the requirements of lubricants. To make up for some of the nature of the defects of lubricants and lubricants to give some new excellent properties, lubricating oil to add a variety of different additives. The addition amount from a few millionths to tens of percent. The role of additives mainly in two aspects: First, change the physical properties of lubricants, such as viscosity, freezing point; Second, increase or enhance the chemical properties of lubricants, such as anti-corrosion and so on. The use of lubricant additives not only meets the requirements of various new types of machinery and engines, but also lengthens the service life of lubricants and reduces the demand for lubricants in the petroleum products.