It is a very important part of a pump. It is a means of preventing migration of fluids across a joint.


- Types of Seals      


Gland Packing :
This was the means used before the development of 'mechanical seal'. Wrapping a spindle or a shaft with a rope like material is termed as gland packing.






Single Mechanical Seal :
The seal consists of mainly two parts - stationary and rotary rings; mounted on the pump shaft and housed in a bellow of a suitable material. The two rings are kept in position and in contact with the help of a spring.


Double Mechanical Seal :
This consists of two independent seals mounted within a seal chamber which is water flushed for lubrication.

Advantage & Application of Double Mechanical Seal :

- To minimize the risk of failure of a single seal design.
- Electroless plating solutions : Double seal contains liquid in the chamber which prevents ' Plating-out' onto the inboard seal faces.
- Concentrated Chemicals.
- High Temperatures.
- Abrasive solutions.
- Containing Critical solution.
- Crystalline Solution.