阅读说明：本技术 一种大型轴流式压缩机轴端密封结构 (Shaft end sealing structure of large axial flow compressor ) 是由 杨方 曹洪强 刘朝 王荣 杨充 荆莎 常少雄 郭丹蕾 韩东 冀雪雁 高磊 杨哲 于 2020-06-25 设计创作，主要内容包括：本发明提出一种大型轴流式压缩机轴端密封结构,包括：壳体、转轴、密封片和弧形石墨条,转轴的轴面上设置有多组密封片,壳体的轴孔处的内侧壁设置有安装槽,每个安装槽内分别装配有多个弧形石墨条,多个弧形石墨条在安装槽内拼接成环形石墨圈,并围在密封片的外侧。本发明的大型轴流式压缩机轴端密封结构可提高轴端密封的轴向抗压性能,有效阻隔高压介质的泄露,提高机组运行效率,能够满足大型轴流式压缩机组轴端密封的应用。(The invention provides a shaft end sealing structure of a large axial flow compressor, which comprises: casing, pivot, gasket and arc graphite strip are provided with the multiunit gasket on the axial plane of pivot, and the inside wall of the axle hole department of casing is provided with the mounting groove, is equipped with a plurality of arc graphite strips in every mounting groove respectively, and a plurality of arc graphite strips splice into annular graphite circle in the mounting groove to enclose the outside at the gasket. The shaft end sealing structure of the large axial-flow compressor can improve the axial compression resistance of the shaft end seal, effectively prevent high-pressure medium from leaking, improve the operation efficiency of the unit, and meet the application of the shaft end seal of the large axial-flow compressor unit.)

1. A shaft end sealing structure of a large axial flow compressor is characterized by comprising: casing (1), pivot (2), gasket (3) and arc graphite strip (4), be provided with multiunit gasket (3) on the axial plane of pivot (2), the inside wall of the shaft hole department of casing (1) is provided with mounting groove (101), every be equipped with a plurality of arc graphite strips (4) in mounting groove (101) respectively, it is a plurality of arc graphite strip (4) are in splice into annular graphite circle in mounting groove (101), and enclose the outside of gasket (3).

2. A large axial compressor shaft end sealing structure according to claim 1, characterized in that the inner side wall of the arc-shaped graphite strip (4) can directly contact with the outer edge of the sealing sheet (3).

3. The shaft end sealing structure of the large axial flow compressor according to claim 1, wherein the mounting groove (101) is a T-shaped groove, and the section of the arc-shaped graphite strip (4) is matched with the section of the mounting groove (101).

4. The shaft end sealing structure of the large axial flow compressor according to claim 3, wherein a dovetail groove (401) is formed in the outer peripheral surface of the arc-shaped graphite strip (4), an arc-shaped convex ring (102) is arranged at the bottom of the mounting groove (101), and the section of the arc-shaped convex ring (102) is trapezoidal and matched with the dovetail groove (401).

5. The large axial flow compressor shaft end sealing structure according to claim 4, wherein the arc-shaped convex ring (102) and the groove bottom of the mounting groove (101) are of an integral structure.

6. A shaft end sealing structure of a large axial flow compressor according to claim 1, characterized in that a plurality of groups of arc bottom grooves (201) are arranged on the rotating shaft (2), and a plurality of sealing sheets (3) are respectively fixed in each group of arc bottom grooves (201).

7. The shaft end sealing structure of the large axial flow compressor as recited in claim 6, wherein the inner edges of the sealing sheets (3) are provided with arc flanges (301), each sealing sheet (3) is respectively padded in one arc bottom groove (201) through the arc flanges (301), and the inner sides of the arc flanges (301) are provided with steel rings (302).

8. A large axial compressor shaft end sealing structure according to any one of claims 1-7, characterized in that two or more mounting grooves (101) are arranged in the shaft hole of the shell (1), and the arc-shaped graphite strips (4) in each mounting groove (101) respectively form a seal with a group of sealing sheets (3).

Technical Field

The invention belongs to the technical field of large axial flow machine sealing, and particularly relates to a shaft end sealing structure of a large axial flow compressor.

Background

Because of market demand changes, users have more and more demand on large axial-flow compressors, and large axial-flow compressors (the shaft end sealing diameter is about 1 m) have overlarge shaft diameter and very high requirement on center balance, after parts are assembled on a rotating shaft, gaps and vibration are easily generated under the working conditions of high heat, high pressure and high rotating speed, so that the selectable shaft end sealing structure is very limited, a volume sealing device is usually sleeved on the rotating shaft, and a non-contact comb seal is usually selected, namely, the comb seal of a rotor embedded sealing sheet is used as the shaft end seal, a shell matched with the seal is made of cast iron, the comb seal of the type usually avoids the phenomenon that the sealing sheet is seriously damaged and the gap is continuously increased or the more serious unit vibration is caused after collision and friction are generated between the sealing sheet on the rotating shaft and the shell due to the vibration and the like when the unit passes through the critical rotating speed, the shaft end sealing clearance design of the large axial flow compressor generally needs to be larger than 0.3 mm-0.4 mm. When the sealing clearance is greater than 0.3mm ~0.4mm, though avoided the gasket to collide with impaired, nevertheless lead to sealed effect not good to unit inefficiency just so must shut down the compressor, changes the gasket, and the maintenance cost is very high.

Disclosure of Invention

In view of the above, it is an object of the present invention to provide a large axial compressor shaft end seal structure for overcoming the above problems or at least partially solving or alleviating the above problems.

The invention provides a shaft end sealing structure of a large axial flow compressor, which comprises: casing, pivot, gasket and arc graphite strip, be provided with the multiunit gasket on the axial plane of pivot, the inside wall of the axle hole department of casing is provided with the mounting groove, every be equipped with a plurality of arc graphite strips in the mounting groove respectively, it is a plurality of arc graphite strip is in splice into annular graphite circle in the mounting groove, and enclose the outside of gasket.

The invention also has the following optional features.

Alternatively, the inner side wall of the arc-shaped graphite strip and the outer edge of the sealing sheet can be in direct contact.

Optionally, the mounting groove is a T-shaped groove, and the section of the arc-shaped graphite strip is matched with the section of the mounting groove.

Optionally, a dovetail groove is formed in the outer peripheral surface of the arc-shaped graphite strip, an arc-shaped convex ring is arranged at the bottom of the mounting groove, and the cross section of the arc-shaped convex ring is trapezoidal and is matched with the dovetail groove.

Optionally, the arc-shaped convex ring and the groove bottom of the mounting groove are of an integrated structure.

Optionally, a plurality of groups of arc bottom grooves are formed in the rotating shaft, and a plurality of sealing pieces are fixed in each group of arc bottom grooves respectively.

Optionally, the inner edge of the sealing piece is provided with an arc-shaped flange, each sealing piece is respectively padded in the arc-shaped bottom groove through the arc-shaped flange, and a steel ring is arranged on the inner side of the arc-shaped flange.

Optionally, the shaft hole of the casing has two or more mounting grooves, and the arc graphite strip in each mounting groove forms a seal with one group of sealing pieces respectively.

According to the shaft end sealing structure of the large axial-flow compressor, the mounting groove is formed in the shaft hole of the shell to embed the replaceable arc-shaped graphite strip, no pressure relief gap is generated, the multiple groups of sealing pieces are arranged on the rotating shaft, the gravity center of the rotating shaft cannot be deviated, the sealing is improved by reducing the gap between the arc-shaped graphite strip and the sealing pieces, the axial compression resistance of the shaft end sealing can be improved, the leakage of a high-pressure medium is effectively blocked, the operation efficiency of a unit is improved, and the application of the shaft end sealing of the large axial-flow compressor unit.

Drawings

FIG. 1 is a schematic cross-sectional view of the integrated oil and gas seal system configuration of the present invention;

Fig. 2 is a partially enlarged schematic view of fig. 1.

In the above figures: 1, a shell; 101, mounting a groove; 102 arc-shaped convex rings; 2, rotating a shaft; 201 arc bottom groove; 3, sealing a sheet; 301 steel ring; 4, arc-shaped graphite strips; 401 dovetail groove.

The present invention will be described in further detail with reference to the accompanying drawings and examples.

Detailed Description