Lubrication system

 LUBRICATION SYSTEM 

Lubrication system is the one of the main and basic system in the engine .The lubrication and hydraulic systems continuously provide clean, cool lubrication and hydraulic fluid to the components at the proper pressure, temperature and flow. 

Source :car and drive

lubrication is required for maintenance of engine.  Lubrication circuit is one of the most important ones in the engine. The engine cannot run smoothly for more than a few minutes without the lubricating oil.  

 Objective of Lubrication 

 The objectives of lubrication are: 

1. Reduce the friction

2. Reduce wear

3. Reduce the heat

4. To provide cooling effect

5. To provide cushioning effect

6. To provide cleaning action

7. To provide a sealing action

Objectives:-

1. Reduce the friction: 

lubricating oil should reduce the friction between two metallic surfaces.

source:MiniPhysics

2. Reduce wear:

 lubricating oil should reduce the wear between two metallic surfaces.

3. Reduce the heat: 

must reduce heat between two metallic surfaces

4. To provide cooling effect:

 The lubricating oil takes heat from the hot moving parts during its circulation and delivers it to the surrounding air through the crank case. 

5. To provide cushioning effect : 

The lubricating oil serves also as a good cushion against the shocks experienced by the engine. For example, instant combustion of the fuel in the combustion chamber produces a sudden pressure rise in the cylinder and the shock goes to the bearings through the piston, gudgeon pin and the connecting rod. This shock is then absorbed by the layer of oil present in the main bearings. 

6. To provide cleaning action :

  The lubricating oil serves another useful purpose in providing a cleaning action. During its circulation it carries away many impurities, e.g. carbon particles.  

7. To provide a sealing action:

The lubricating oil also helps the piston rings to maintain an effective seal against the high pressure gases in the cylinder from leaking out toward the crank case side. 

Automobile Engine Lubrication 

source:softinway.blog

The main parts of an automotive engine which require lubrication are: 

• Main crankshaft bearings

 • Big end bearings 

• Gudgeon pin bearings 

• Piston rings and cylinder walls 

• Timing Gears 

• Camshaft and camshaft bearings

Properties of a good lubricant 

1. Viscosity:

2. Physical stability

3. Chemical stability

4. Resistance against corrosion

5. Pour point

6. Flash point

7. Cleanliness:

Properties of a good lubricant :

1. Viscosity: Resistance to flow of lubricating oil

source:cradle-cfd

2. Physical stability: The lubricating oil should be physically stable in higher and lower temperature

3. Chemical stability: The lubricating oil should be chemically stable in higher and lower temperature

4. Resistance against corrosion: The oil should not have any tendency to corrode the pipe lines, crank case and other engine parts with which it comes into contact.

Source:Team-BHP

5. Pour point: The minimum temperature the oil should be pour called pour point

Source:Fluidsolution inc

6. Flash point: The minimum temperature the oil should be flash called flash point

Source:Wikipedia
7. Cleanliness: The lubricating oil should be sufficiently clean and stable itself.

Types of Lubricants 

 Depending on widely varying requirements of different parts, the automotive lubricants may be classified as below. 

1. On the basis of their state 

• Solid lubricant such as graphite, soapstone, talc, mica, molybdenum di sulphide.

Source:slideshare
 • Semi-solid lubricants such as greases e.g., aluminum paste. 
Source:TPCE mech books

• Liquid lubricants such as mineral oil, vegetable oils, animal oils.

Source: machinery lubrication
 • Emulsions such as oil in water. 



Source:Hindawi

2. On the basis of their origin 

• Natural lubricants such as mineral oils, vegetable oils, animals oils, graphite. 

Source:tesco
• Synthetic lubricants such as refined petroleum oils, commercial grade oils, grease. 

Source:fuels and lubes

3. On the Basis of Variation in Viscosity

 • Mono-grade oils such as SAE 20, SAE 30, SAE 50 etc.

Source:swgiftec

 • Multi-grade oils such as SAE 20W 40, SAE 15W 40 etc.

Source:Amazon.in

 4. On the basis of special preparation 

• Blended lubricants such as blended by castor oil, palmitic acid, oleic acid. 

• Compounded lubricants such as compounded with polyglycols, fluorocarbons, silicones.




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