The Components Of Agents In The Engine Oil Additive Package
Engine oil （发动机油） is a very complex oil. Today's high-performance engine oil contains a variety of components, such as advanced additives and base stock, viscosity improver, etc. Each component plays their important parts, and finally forms a balanced formula.
In order for the oil to perform the required functions, oil producers have to carry out careful modulation of lubricating oil and tests, making it meet or exceed certain specifications or performance requirements for the engine oil. This article introduces common additive components in a complex engine oil modulation and all the requirements for the formula.
Base Stock （基础油）
First of all, let's explore the base oil. The American petroleum institute (API) categories base oil into five groups, each categories with different technology and performance characteristics. Although base oil is the largest component (typically accounting for 60-95% of the weight) of heavy vehicle engine oils, and even with the best quality, the base oil is impossible to achieve all-round protections for engine, from various factors such as high temperature, shear force, worn particles, chemical and water dilution, and corrosion.
In the development of compound additives, it is necessary to consider the characteristics of the base oils to be used, as each type of base oil has different requirements for additive formulation.
Viscosity Index Improver （粘指剂）
Viscosity index improver is a specially designed copolymer agent, applied to modulate the viscosity (consistency) of lubricating oil for a specific temperature range and working environment. With engine parts becoming more sophisticated, advanced polymers will not only help the engine to operate more efficiently in the increasingly harsh environment, but also enhance the durability and protecting ability.
A variety of viscosity index improvers has been developed, and the specific choice depends on a variety of related factors, including the characteristics of the base oil, additive properties, and the working environment of the lubricating oil.
Although additives are relatively small components in lubricating oils, they play a significant role in the protection of key parts of the engine. Lubricant oil usually includes the following additives:
Clearing agent (清净剂)
Clearing agent or detergent is a kind of additive used in fuel or lubricating oil, its role to keep engine parts clean in the motor. The most commonly used clearing agent is alkaline metal soap detergent, which can neutralize the acidity produced in the combustion process.
Dispersant can keep the pollutants suspending in the oil, to prevent oil sludge and film formation on engine parts. Dispersant is usually a non-metallic material (ashless), to be used together with the detergent (control of pollutants).
Antioxidants are also known as oxidation inhibitors, which are used to slow down the oxidation of oil.
Anti wear agent (抗磨剂)
Anti-wear agent is used to form tough films on the highly loaded components, to block the direct contact and locking between metal surfaces.
Anti friction agent (摩擦改进剂)
Anti friction agent adheres to the surface components of engine parts, and reduce the friction and wear when slight friction occurs. Friction depends on the smoothness of the contact surface, and the pressure between the two surfaces.
Anti foaming agent抗泡剂
The purpose of anti foaming agent is to suppress the foam forming process in the lubricating oil. Foams can cause gas cavities in the pump and reduce the fluidity of lubricants.
Anti rust agent 腐蚀抑制剂
Anti rust agent or corrosion inhibitors are used to prevent metal surfaces from chemical reactions with water or other pollutants (control corrosion and acid)
Pour point depressant 降凝剂
Pour point depressant can reduce the pour point of a petroleum product, which is the fluidity under low temperature and shear. (control viscosity)
All additives above must go with a balanced allocation, to perform specific functions that a lubricating oil requires. Only through complex preparation and formulation with professional technology, a formula can achieve the desired effect with the base oil blending well with the additives and viscosity modifiers, so that all the components do not conflict with each other while playing their parts.
If one kind of additive content is higher, it may inhibit other additives and viscosity index improver from playing their role. For example, if anti foaming agent content is too low, lubricating oil will form bubbles and cavitations and cause damage to the engine. A wrong type of detergent is used, the acidity in the oil cannot be neutralized and the dispersant couldn’t effectively prevent the soot formation and precipitation on the engine parts. Therefore, the proportion of all ingredients must be accurate to reconcile together to perform all the functions. Use professional knowledge to allocate the proportions of agents in a compound additive, to meet the various requirements from the durability to the protection, so as to realize excellent fuel economy and efficiency.