Bi-directional movable shaft seal using liquid for isolation

Abstract

The invention relates to the technical field of dynamic sealing, in particular to a structure for sealing a medium in rotating equipment. A bi-directional movable shaft seal using liquid for isolation is mounted on a rotating shaft. The bi-directional movable shaft seal comprises a liquid collecting cavity located in the middle, and an upper boosting cavity and a lower boosting cavity which communicate with the liquid collecting cavity, wherein a boosting structure is arranged on the inner wall surface of the upper boosting cavity or the outer wall surface, opposite to the inner wall surface of the upper boosting cavity, of the rotating shaft; a reverse boosting structure is arranged on the inner wall surface of the lower boosting cavity or the outer wall surface, opposite to the inner wall surface of the lower boosting cavity, of the rotating shaft; the liquid collecting cavity is filled with sealing liquid; and when the rotating shaft rotates clockwise or anticlockwise, both the boosting structure in the upper boosting cavity and the reverse boosting structure in the lower boosting cavity guide the sealing liquid to flow towards the liquid collecting cavity. Under the action of the boosting structures, the sealing liquid can be defined in the liquid collecting cavity, the sealing liquid in the liquid collecting cavity is used as an isolating medium, and the function of sealing the medium in the rotating shaft is realized.

Description

technical field [0001] The invention relates to the technical field of dynamic sealing, in particular to a structure for sealing media in rotating equipment. Background technique [0002] In rotating equipment, such as pumps, fans, etc., it is necessary to seal the medium in the equipment. When the rotating equipment is running, the shaft is rotating, but the part fixed to the equipment casing is stationary, so a sealing structure is needed to realize dynamic sealing. Commonly used dynamic seal structures include mechanical seals, packing seals, labyrinth seals, etc. These sealing structures have their own characteristics. For example, although the mechanical seal has a good sealing effect, its structure is precise and easy to damage. The packing seal has a simple structure and many application occasions, but its service life is short, and it belongs to direct contact seal. The moving and static parts directly rub against each other during use, so the service life is short...

AI Technical Summary

Problems solved by technology

These sealing structures have their own characteristics. For example, although the mechanical seal has a good sealing effect, its structure is precise and easy to damage.

The packing seal has a simple structure and many applications, but its life is short, and it is a direct contact seal. The moving and static parts are directly rubbed during use, and the life is short.

The labyrinth seal structure is relatively simple, but the medium on the seal side and the outside are only separated by the labyrinth structure of the labyrinth seal, which cannot avoid a small amount of leakage of the medium from the seal side to the outside

For some labyrinth structures that have both throttling and micro-screw pump functions, the shaft is required to rotate in a certain direction, and the application of shaft seals has strong limitations.

Images