![]() Water and polar impurities increase the speed of attack. The rate of oxidation doubles with every 10º C rise in temperature. This vicious cycle leads to an increase in rust and corrosion, resulting in metal damage from oxygen and acid attack. Oxidation will lead to an increase in the oil’s viscosity and deposits of varnish and sludge. ![]() Antioxidants – Compounds designed to retard oxidative decomposition.Often composed of silicone polymers or organic copolymers. Reduces the surface tension of the fluid to speed the collapse of foam. Antifoam Agents – Prevents lubricants from forming a persistent foam.At low temperatures, the wax tends to separate, trapping a substantial amount of oil, inhibiting oil flow and hindering lubrication. In general, the pour point is indicative of the amount of wax in an oil. Pour Point Depressants – Designed to enable lubricants to flow at lower than normal temperatures (compared to the base oil in its natural state).At high temperatures, the chain relaxes and an increase in viscosity sity modifiers are polymeric molecules that are sensitive to temperature. At low temperatures, the molecule chain contracts and does not impact the fluid viscosity. Viscosity improvers are polymeric molecules that are sensitive to temperature. Viscosity Improvers – VI improvers (also known as viscosity modifiers) are additives that increase the viscosity of the fluid throughout its useful temperature range.This is caused by a chemical reaction with elastomer to cause slight seal swell as specified by the manufacturer (OEM). Seal Swell Agents – Their express purpose is to swell elastomeric seals.These are also called boundary lubrication additives. ![]() Friction Modifiers – Minimises light surface contacts (sliding & rolling) that may occur in a given machine design.Thereby preventing metal to metal contact. Chemical reaction with metal surface forms a film with lower shear strength than the metal. ![]()
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