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:
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.