Additives For Lubricants

Introduction:

The additives when correctly formulated into lubricants enable them to ‘stay in grade’.  Most modern lubricants and coolants contain organometallic oil additives. Some of these additives are formed from compounds of one or more of the same chemical elements used in component parts.

 

Main purposes of lubricant additives:

• - Lubricant protection
  Inhibition of thermo-oxidative degradation: Antioxidants
  Inhibition of catalytic effects of the metal surfaces: Metal deactivators and Corrosion inhibitors
• - Metal surface protection
  Wear inhibition: Extreme Pressure/ Antiwear additives (EP/AWs) and friction modifiers
  Rust prevention: Corrosion inhibitors
  Yellow metal attack prevention: Metal deactivators
• - Flow protection
  To decrease the temperature at which non-synthetic lubricants start to solidify: pour point depressants.
  To help lubricants function at elevated temperatures, supporting continued equipment operation:
  Viscosity Modifiers.

 

MOLYBDENUM

Extreme pressure additive in specialty oils and greases; corrosion inhibitor in some coolant supplemental additives

MAGNESIUM

Detergent, dispersant, alkalinity increaser

SODIUM

Corrosion inhibitor in oils and coolants

BORON

Detergent, dispersant; anti‐oxidant in oils and coolants

BARIUM

Corrosion and rust inhibitors; detergent; anti‐smoke additive in fuels

PHOSPHORUS

Anti‐wear; combustion chamber deposit reducer; corrosion inhibitor in coolants

POTASSIUM Compounds

Corrosion inhibitor; trace element in fuels; also found as a mineral salt in sea water

CALCIUM

Detergent, dispersant, alkalinity increaser

ZINC

Anti‐wear, anti‐oxidant, corrosion inhibitor

ANTIMONY

Anti‐wear, anti‐oxidant

The modern lubricants for heavy duty engines are highly refined which otherwise may produce sludge or suffer a progressive increase in viscosity. For these reasons, the lubricants are seasoned by the addition of certain oil soluble organic compounds containing inorganic elements such as phosphorus sulphur, AMINE derivatives. METALS are added to the mineral based lubricating oil to exhibit the desired properties. the oil soluble organic compounds added to the present day lubricating to impart one or more of the following characteristics.

• Anti-oxidant and anti-corrosive agents
• Detergent-dispersant
• Extreme pressure addition
• power point depression
• viscosity index improver
• antifoam agent
• Oiliness and film-strength agents.