Lubricant is a substance used for lubricating an engine or component, such as oil or grease, in order to reduce friction between surfaces in mutual contact. It also reduces the heat generated when the metallic surfaces move. Depending on the application, we use either lubricating oil or grease.
Following are some of the primary functions of lubricants:
Prevents physical contact of moving parts
Lubricants provide a protective layer that acts as a physical barrier between the moving parts. This reduces friction and surface fatigue leading to reduced heat generation, operating noise, and vibration.
Lubricant-to-surface friction is significantly less than surface-to-surface friction. Thus the use of lubricant reduces the overall system friction between load-bearing surfaces which translates into reduced heat generation, reduced formation of wear particles, and improved efficiency.
Transfer of heat
Lubricants work as an initial heat transfer agent between some heated combustion and heat dissipating systems. The liquid lubricants, like engine oils, constantly circulate inside the engines, thereby transferring heat away from localized hot spots and simultaneously warming cold surfaces. It helps to cool the engine from fluid friction and combustion of fuel.
Cleaning contaminants and derbies
Deposits such as solid carbon, varnish, and sludge can interfere with the correct and efficient operation of the equipment. Piston rings might get stuck and oil passages get blocked. Lubricants can prevent this by improving the viscosity control of oils.
Lubricant circulation systems also carry away internally generated debris and external contaminants that get introduced into the system to a filter where they can be removed. Lubricants for automotive engines often contain detergent and dispersant additives which assist in debris and contaminant transport to the filter for removal.
Lubricants like hydraulic fluid are used as the working fluid for hydrostatic power transmission.
Protects against wear
Lubricants keep moving parts apart thereby preventing wear. Lubricants may also contain anti-wear or extreme pressure additives that boost their performance against wear and fatigue.
Prevents corrosion and rust
Good quality lubricants are typically formulated with additives that form chemical bonds with surfaces which exclude moisture, to prevent corrosion and rust. It reduces corrosion between two metallic surfaces and prevents contact between these surfaces to avoid immersed corrosion. Corrosion is also prevented by flushing derbies from between moving parts.
Lubricants assist in forming seals between pistons and cylinders. High quality oils can provide increased bearing protection.
Help Save Costs
Good quality lubricants reduce drain interval leading to cost savings with respect to materials.