SU1762065A1 - Noncontact sealing device - Google Patents

Abstract

The invention relates to a sealing technique. The purpose of the invention is to increase the sealing efficiency. The sealing device consists of a shaft 1, a housing 2 and a disk 4 mounted on the shaft 1 located in the annular chamber 3 of the housing 2 with radial blades 5 on its base surface 6. Axial clearances 6 between the end surfaces of the blades 5 and the matching end flat wall 7 chambers 3 are cyclically variable in the circumferential direction, which has an additional mechanical effect on the working fluid in the seal cavity and leads to additional turbulence and vortex formation. 2 hp ff, 3 ill.

Description

The invention relates to a sealing technique, in particular to contactless sealing devices of the impeller type of rotating shafts of hydraulic machines.

The purpose of the invention is to increase the sealing efficiency by increasing flow turbulence and flow resistance in the axial clearance.

FIG. 1 shows a sealing device in longitudinal section; in fig. 2 - scan the outer cylindrical surface of the impeller when performing blades of equal height; in fig. 3 - the same when performing blades of variable height.

The device consists of a shaft 1, a housing 2 and a disk 4 mounted on the shaft 1 located in the annular chamber 3 of the housing 2 with radial vanes 5 on its base surface 6, with axial clearances between the end surfaces of the blades 5

and the counter face flat wall 7 of the chamber 3 are cyclically variable in the circumferential direction

The blades 5 can be made equal in height and placed one at a time or in groups on axial protrusions 8 of a non-planar base surface 6 of disk 4 (FIG. 2), or made cyclically variable in height in the circumferential direction and placed on a base the surface 6 of the disk 4 (Fig. 2)

The sealing device operates as follows.

When the shaft 1 rotates, the working fluid in the seal cavity is in a complex motion in both axial and radial directions. The presence of a cyclically variable in the circumferential direction of the gap between the blades 6 and the wall 7 means that, in addition to the blades 5, there is an additional series of peculiar blades, due to the presence of protrusions 8 on the base

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Claims (3)

surface 6, or the presence of increased-sized blades (or groups of blades 5, the same height). The number of these blades corresponds to the cyclicity in the change of the specified gap. These blades have an additional mechanical effect on the liquid, which significantly changes the flow pattern, leads to additional turbulence and transformation, to an increase in the hydraulic resistance of the entire path and, as a result, to an increase in the effectiveness of sealing. Claim 1. Non-contact sealing device comprising a shaft, a housing, as well as an open type impeller in the form of a disk mounted on a shaft with radial vanes on a base surface located in an annular chamber of the housing with axial gaps between the end surfaces of the blades and the corresponding flat end wall of the chamber in order to increase sealing efficiency by increasing flow turbulization and flow resistance, the gaps between the end faces current response and the end surface of the housing chamber wall made cyclically varying in the circumferential direction. 2. The device according to claim 1, that is, with the fact that the blades are made the same in height and placed one by one or in groups at a non-planar cyclically variable in height in the circumferential the direction of the base surface of the disk. 3. Device pop. 1, characterized in that the blades or their group are made cyclically variable in height in the circumferential direction and are placed on a flat surface that is perpendicular to the axis of the disk. Rie.1 fiag Lj fiue.3