PUMP-CONVEYED FLUID DYNAMIC-PRESSURE MECHANICAL SEAL

摘要

A pump-conveyed fluid dynamic-pressure mechanical seal is formed of a dynamic ring (3), a static ring (11), and the like. More than three reversely-bent fluid grooves (39) are opened on a sealing surface of the dynamic ring of the mechanical seal, an outlet is located at the outer diameter of the sealing surface of the dynamic ring, and an inlet (31) is connected to sealing cavity (1) through an opening (30) on the dynamic ring (3) or the static ring (11). During the rotation of the dynamic ring (3), a medium in the fluid groove (39) is accelerated to be a high-speed fluid; under the effect of a centrifugal force, the high-speed fluid flows to a side of the outer diameter of the dynamic ring (3) and is pumped and conveyed into the sealing cavity, and forms a low-pressure area at the inlet (31) of the reversely-bent fluid groove (39). Under the effect of a pressure difference, the medium inside the sealing cavity (1) flows into the reversely-bent fluid groove (39) through the opening (30), so as to form a new pump conveyance cycle. In the process that the high-speed fluid is pumped out, with the gradual increase of the flowing cross section of the reversely-bent fluid groove, the flowing sped decreases, and the pressure increases, so as to form an opening force for separating a dynamic ring and a static ring. The sealing has desirable capabilities of self-lubrication, self-cleansing, and endurance to interference of solid particles, and optimal sealing performance.