General

Mechanical seal refers to a device for preventing fluid leakage caused by at least one pair of end faces perpendicular to the rotation axis under the action of fluid pressure and compensating mechanism elastic force (or magnetic force) and the cooperation of the auxiliary seals. The elastic loading mechanism and the auxiliary seal are mechanical seals of the metallic bellows, which we call metal bellows seal. Due to the limited elastic force of the rubber bellows, in the light seal, the rubber bellows is used as the auxiliary seal, and it is generally necessary to use the spring to increase the spring force. 
 

Structure 
1. Main parts of the mechanical seal are dynamic ring and static ring.
2. Auxiliary seals: O-shaped, X-shaped, U-shaped, wedge-shaped, rectangular flexible graphite, PTFE coated rubber O-ring and etc.
3. Elastic compensation mechanism: spring, push ring, spring seat and key or various screws.
4. Divided into single end, double single side, balanced type, unbalanced type, any direction of rotation, fixed rotation.
 

Principal
The mechanical seal is a shaft seal device that resists leakage by a pair of or pairs of end faces that are relatively slid perpendicular to the shaft under the action of the fluid pressure and the elastic force (or magnetic force) of the compensating mechanism.
The general mechanical seal structure consists of stationary ring (static ring), rotating ring (dynamic ring), elastic component, spring seat, screw, rotating auxiliary seal ring and static auxiliary sealing ring, and the anti-rotation pin is fixed at the pressure cover to prevent the static ring from rotating.
Rotating ring and static ring can be referred to as compensating ring or uncompensated ring depending on whether they have axial compensating capabilities.