Hydraulics and Pneumatic Machines – JSS2 Basic Technology Lesson Note (Third Term)

Hydraulics and pneumatic machines

Topic: lubrication 

LUBRICATION: is the process of applying a lubricant (substance such as oil or grease) to an engine or components to reduce friction and allow smooth movement. 

LUBRICANT: a substance such as oil or grease that reduces friction when

They are applied as a surface coating to moving parts. 

Examples of effective lubricants are: 

1. Grease 
2. Oils 
3. Penetrating lubricant 
4. Dry lubricant 

FUNCTION OF LUBRICANTS

1. To reduce friction 
2. To prevent wear 
3. To protect the equipment from corrosion 
4. To control temperature (dissipate heat) 
5. To control contamination (carry contaminants to a filter or sump) 
6. To transmit power (hydraulic) 
7. To provide a fluid seal. 

PROPERTIES OF A GOOD LUBRICANT 

1. A high viscosity index 
2. Thermal stability 
3. Hydraulic stability 
4. Demulsibility 
5. Corrosion prevention.

REDUCING FRICTION EFFECTS BETWEEN MESHING GEARS 

When two gear teeth mesh together, they usually rub against one another such that the frictional effect generates heat and wear on the surface. To reduce wear loss of power transmission, friction between the meshing teeth must be reduced. This is achieved by lubricating the gears with suitable gear oil. 

FUNCTIONS OF LUBRICANTS IN GEAR 

1. Reduce friction between moving parts 
2. Prevent heat build-up 
3. Protect moving surfaces 
4. Help remove and trap harmful chemicals in the engine 
5. Act to deaden sound 
6. Help prevent corrosion of metal 
7. Prolong the life