What are the lubricant additives?

What kinds of lubricating oil additives are there?

With the development of machinery industry, the requirements for lubricating oil are becoming higher and higher

It is economical and effective to add various additives to the lubricating oil to improve the quality of the oil

Lubricating oil additives can be divided into:

– antiwear agent, detergent, dispersant, antioxidant, anti-corrosion and anti rust agent, antifriction agent, viscosity index improver, pour point depressant, anti foaming agent, etc

Antiwear agent

Objective: to reduce friction and wear

Typical compounds: sulfur, phosphorus, chlorine, lead and other compounds. Such as sulfurized olefins, chlorinated paraffins, ZDDP, borates, etc., they form an adsorption film or reaction film on the friction surface to protect the friction surface.

Detergent

Objective: to keep the friction surface clean and neutralize the acidic substances produced by the deterioration of lubricating oil

Typical compounds: sulfonate, alkyl phenol salt, barium sulfide polyisobutylene salt, alkyl salicylate, etc

dispersant

Objective: to keep the insoluble matter in the oil suspended and not deposit in the oil passage or friction pair to prevent further condensation

Typical compounds: ester compounds with long chains

Antioxidant

Purpose: to prevent oxidation of lubricating oil

Typical compounds: phenol salt, ZDDP, amine salt, sulfur / phosphorus compound, etc. generally protect the lubricating oil by sacrificing themselves

Corrosion and rust inhibitor

Objective: to protect non-ferrous metals from corrosion and prevent ferrous metals from corrosion

Typical compound: oil containing compound with polarity. Generally, it plays a protective role by adsorbing on the metal surface

Viscosity index improver

Objective: to improve the viscosity temperature performance of lubricating oil and obtain the required viscosity characteristics

Typical compounds: high molecular compounds or polymers, such as PIB, OCP, HSD, PMA

Pour point depressant

Objective: to reduce the freezing point of lubricating oil

Typical compounds: generally high molecular compounds with polar groups, such as polymethacrylate, alkyl naphthalene and other compounds

Antifoaming agent

Objective: to reduce the foaming of lubricating oil in use or eliminate foam in time.

Typical compounds: generally methyl silicone oil or polyacrylate compounds

– special additives for changing oil-gas interfacial tension

– promote the rapid rupture of bubbles on the oil surface

Lubricating oil formula

It is not simple to add additives to the oil to get the corresponding products

Unknown effects may occur between different additives

The more additives, the better. There is also an appropriate amount

The quality of lubricating oil depends not only on the formulation of additives

The performance of base oil is very important to the performance of finished lubricating oil