Mechanical Seals

Mechanical seals are also used to stop leakage along the pump shaft (same purpose as that for the compression packing.) The objectives of a mechanical seal are:

a. Control leakage along the pump drive shaft.

b. Prevent leakage of air into the pump under suction lift conditions.

The figure provided here is a schematic for a common mechanical seal. In later sections more details are provided for this basic seal. Over time hundreds of designs have been developed to improve the basic design - but fundamentals of how they work remain the same.