Sanitary Self-priming Pump Mechanical Seal

The mechanical seal acts as a check valve and a slider bearing. The obvious function is that of a check valve to prevent liquid under pressure from leaking out of the pump, or from drawing air into the pump when under vacuum conditions.

Mechanical seals are simple devices. There are metal parts including a spring, a stationary seat, and a rotating seat (also called the primary ring) and there are the elastomers parts.