Seal: The seal is an agent or element which prevents leakage of oil from hydraulic elements and protects the system from dust and dirt.

Classification of seals based on shape:

a) ‘O’ Ring seal b) ‘V’ Ring seal c) U-packing seal d) T- ring seal e) Cup seal

Factors for seal selection:

1) Type of fluid used in system

2) Maximum temperature of system in working condition

3) Functional reliability expected

4) Cost of seal

5) Working pressure of system

6) Environmental condition