Description
A mechanical seal is a machine element made to seal the passage point of a rotating part (usually a shaft) through a wall (usually the machine casing). Features of the mechanical seal are two surfaces sliding on each other – usually arranged at right angles to the rotational axle – which are pressed together by axial forces. Between the sliding surfaces is a liquid or gaseous lubricating film. Single or double acting mechanical seals are used to seal the shaft gland. Sealing is achieved through axial sliding faces which are pressed against each other by spring force and this prevents them opening when at rest. The stationary part of the mechanical seal usually sits in a housing and the rotating unit on the shaft sleeve. In the sealing gap between the sliding faces a lubricating film is generated by the pumped medium in order to prevent the sliding faces running dry. Every mechanical seal possesses five basic1.One ring (usually the seal face) circulating synchronously with the rotating part (shaft)
2.Secondary seal (usually O-ring) between shaft and ring
3.A stationary ring (usually the stationary seat) arranged in the stationary part (casing)
4.Secondary seal (usually O-ring) between these parts
5.Spring for the seal face