lubricating oil properties
These properties are dependent on duties a lubricant is expected to perform :-
1.Detergency :-Detergency of oil is obtained by adding some metallic based additives which will prevent the build up of small deposits in the metal surface.In 2 -stroke ,it is very important as it removes the deposits from ring pack area and keeps the combustion space as clean as possible.
2.Dispersancy :-It is the property of L.O which prevents impurities to mix up with itself and keeps them suspended in the surface .This makes it easy for the separator or clarifier to remove it from the oil.
3.Anti-emulsion :- It is the property of lubricating oil to separate from water in a non-miscible emulsion.Example :- Water ingress into lubricating oil requires the water to be separated ,so that water can be removed.
4.Anti -Bacterial :- It is property in which no any microbial degradation is there.Bacteria attacks metals and forms has resulting in corrosion of steel.
6.Anti -oxidation :- It is the tendency to resist oxidation.Additives are used to improve this property.Ex-Amines or organic metallic additives.
7.Viscosity :-It determines the resistance of oil internal cohesive forces and protest setting up of certain conditions for friction between the moving surfaces.
8.Viscosity Index :-It is the property con lubricating oil to resist the change in viscosity as per change in temperature.
9.Alkalnity :- When fuel burns,the fumes carry H2So4 which can cause acidic corrosion .For a trunk piston engine or 4 stroke engines the main lube oil is responsible for piston and liner lubrication.Hence it comes directly in contact with the combustible fuel.Thus,it is very important but for 2 -stroke engines separate grade of lube oil is important for controlling acidic corrosion.
10.Therma Stability :- It is the property of the oil to be stable and resist cracking at high temperature (Preventing thermal stress )
11.Anti – foaming :- Preventing the undesirable phenomenon of the oil mixing with air resulting in cavitations and overheating.
12.Anti -wear properties :-Koad carrying capacity to withstand pressure inside the engine .If not achieved the oil will forced out and metal to metal contact will result in wiping out and and wear down of the machine.
13.Oiliness and EO Additive oils :- It us the tendency of oil to adhere or wet the moving surface.