What is lubricants?

lubricants :- 

lubricant is a kind of substance which is used to minimise the friction of the two continiously moving body.

in any type of mechinery due to the presence of moving parts there is constant rubbing of the surface of the moving parts of the mechinery this resistance between the mechinery is known as friction.  

this friction is not good for the life of the mechinery hence it casuses wear and tear to the parts of mechine which also afecs the life and efficiency of the mechinary.

the friction inside the rolling or movin parts in the mechinary not only causes the wear and trear of the moving parts of mechine but also release a large amount of heat energy which effects the efficiency of the mechinery 

to minimise the friction between the moving parts of mechine some substence are inceeted between the moving parts of he mechinery to reduce the friction of the mechine these substance forms the thin layer in between two moving or sliding bodies by application of lubricants betweeen them is known as lubrication

in another words we can say that the substance which is introduced between the moving and silliding mechinery parts to reduce the frictional resistance between to fix the problems of wear ad tear in the moving mechinery parts 

and the process of reducing the friction in between the rolling and silliding parts of mechinery to overcome with the problem of wear and tear is known as lubrication 

as we know the surface of metal which is used in the mechine are never perfectly smooth and the have a irregularities in the form of elevation(which is the peak point) or depression (which is valleys) at the microscopic level 

when the moving metal surface came in the contact during moving of these metal parts, these parts gets rubbed against each other the asperties get welded due to the local mealting and some energy has to be spent to break the welded junction 

the asperties begins deforming and flattening out. this causes the formation of weed junctiojns ploughing or cutting out the softer material by the aspeties of the harder materials and the interlocking of the surfqace irregularities.

this friction produces due to the irregularities of the rolling and slidding metal surface this may cause damage to the mechinery in three ways 

1. heat generation :- 

the irregular surface of the rolling and sliding metals cause the production of huge friction and this friction leads to the generation of heat in the large amount and these produces heat may change the shape and size of the machinery parts which causes deformation of the machines 

2. energy loss :- 

this is another problem that arises due to friction. the power which is supplied to the machinery doesn't convert totally into the work some amount of energy is lost in terms of heat or in other form and which is determined as the energy loss

 

3. material loss :- 

the next disadvantages of the friction which is produced inside the machine is the loss of materials of the moving or sliding parts of the machinery and due to the difference of the hardness of these moving bodies leads to the lost of the materials 

function of lubricants :- 

as we see above the working of the lubricants and the requirements of the lubrication inside the machinery

now we will see the functions of the lubricants 

1. the very first function of a lubricant is it reduces the friction inside the machinery 

2. As we see above, it forms a thin layer over the rolling or sliding surface so it prevents the direct contact of these rubbing surfaces so that it reduces the wear and tear and surface deformation. by this it cure the machine from maintenance cost 

3. it also works as a coolant and prevents machine from heating effect 

4. By reducing the heating effect it prevents the expansion of metal by local frictional heat. 

5. it avoids the seizure of moving surfaces that's why the use of lubricant reduces the liberation of frictional heat 

6. also it makes the movement much smooth relatively 

7. it absorbs shocks between bearing and and in the moving parts of engine and contributes in reducing the noise of the machine 

8. also in an internal combustion engine it ac as a seal by sealing the piston and cylinder at the compression ring by this it protects the leakage of gasses at the high pressure in the compression chamber 

9. The lubricant also carried away the contaminated products from the rear parts of the machine so they may be removed from the system by oil draining or by oil purification system. 

so above we get the knowledge about the lubricants and also we come to know about the various different applications of lubricant. 

BY :- ADARSH GUPTA