CN215980866U

CN215980866U - Packing sealing device for large butterfly valve

Info

Publication number: CN215980866U
Application number: CN202122040962.8U
Authority: CN
Inventors: 林毅铭; 朱文宣; 陆荣华; 王晨; 刘亮; 吴上予
Original assignee: Huaneng Shanghai Electric Power Maintenance Co ltd
Current assignee: Huaneng Shanghai Electric Power Maintenance Co ltd
Priority date: 2021-08-27
Filing date: 2021-08-27
Publication date: 2022-03-08
Anticipated expiration: 2031-08-27

Abstract

The utility model relates to a packing sealing device for a large butterfly valve, which comprises a packing chamber arranged at the upper end part of a valve body of the butterfly valve and a packing gland assembled with the packing chamber, wherein the packing chamber comprises an annular mounting shell, and a first packing chamber and a second packing chamber which are arranged in the annular mounting shell and are communicated with each other, the first packing chamber and the second packing chamber are arranged at the central position of the annular mounting shell, the diameter of the first packing chamber is larger than that of the second packing chamber, the second packing chamber is assembled and connected with the packing gland, and the joint of the first packing chamber and the second packing chamber is provided with an oblique angle for installing an O-shaped ring. Compared with the prior art, the utility model has the advantages of reducing the leakage of the packing chamber, prolonging the service life of the valve and the like.

Description

Packing sealing device for large butterfly valve

Technical Field

The utility model relates to the technical field of butterfly valves of power plants, in particular to a packing sealing device for a large butterfly valve.

Background

At present, domestic or imported butterfly valves are used in circulating water systems of domestic and foreign 300MW and 600MW units produced by a plurality of domestic power plants, such as: the large butterfly valve generally comprises a packing chamber arranged at the upper end part of a valve body, packing arranged in the packing chamber, a packing gland positioned on the valve body, a valve rod arranged at the central part of the valve body, a related pressure platform and other components. However, in the daily operation process of these large butterfly valves, the defects of leakage of the packing chamber and the like generally occur, and the workload of maintenance personnel is increased.

The top of the valve body of the traditional large butterfly valve is provided with a packing chamber, and the traditional packing chamber is of a first-order structure and is sealed by adopting flexible packing; and the locking form of the packing gland adopts two-point fixation. After the traditional packing sealing structure is used for a period of time, the packing assembly is extruded unevenly when the packing assembly is extruded due to the fact that the extrusion of the valve body easily reaches the limit of deformation of the packing assembly, so that the packing is leaked, the sealing effect of the device is reduced, the service life of the valve is easily influenced, and the stable operation of a unit is further influenced. Due to the position specificity and the structure specificity of the valve, the difficulty of on-line maintenance is high and the expected effect of repair cannot be achieved necessarily.

SUMMERY OF THE UTILITY MODEL

The present invention is directed to overcoming the above-mentioned disadvantages of the prior art and providing a stuffing seal for a large butterfly valve.

The purpose of the utility model can be realized by the following technical scheme:

the utility model provides a packing sealing device for large-scale butterfly valve, is including locating the packing chamber of the valve body upper end of butterfly valve and the gland that is used for with the packing chamber assembly, the packing chamber includes cyclic annular installation casing and locates the first packing cavity and the second packing cavity that link up each other in the cyclic annular installation casing, first packing cavity with the second packing cavity is located the central point of cyclic annular installation casing puts, the diameter of first packing cavity is greater than the diameter of second packing cavity, second packing cavity and gland be assembled between/be connected.

Preferably, the joint of the first packing chamber and the second packing chamber is provided with a bevel angle for installing an O-shaped snare.

Preferably, an O-ring groove for mounting an O-ring is formed in a joint surface of the annular mounting shell corresponding to the second packing chamber and the valve body.

Preferably, the annular mounting shell is provided with a mounting mechanism which is assembled and connected with the packing gland.

Preferably, the mounting mechanism comprises four first bolt holes which are arranged on the peripheral outer surface of the annular mounting shell and have a cross structure.

Preferably, the packing gland includes discoid base and the cylinder of locating on the discoid base, the cylindrical center is equipped with central through hole, central through hole runs through the setting of discoid base, four second bolt holes have been seted up to the upper surface of discoid base for cross structure, set for position, the size phase-match of second bolt hole with set for position, the size of first bolt hole.

Preferably, the bevel is a 15 ° bevel.

Preferably, the width of the O-shaped ring groove is 6mm, and the depth of the O-shaped ring groove is 3 mm.

Preferably, a flexible packing is disposed within the second packing chamber.

Preferably, flexible graphite packing is disposed within the second packing chamber.

Compared with the prior art, the utility model has the following beneficial effects:

1) the O-shaped ring is additionally arranged between the packing chamber and the valve body, so that the problem of leakage between the valve body and the packing chamber can be effectively solved, in addition, the improved packing chamber is also internally and additionally provided with the O-shaped ring, the leakage of the packing chamber can be greatly reduced, and further, the workload of daily maintenance personnel can be reduced.

2) The packing chamber comprises two packing chambers with different diameters, namely, multi-stage multi-form sealing is changed, and a packing gland locking form adopts four-point fixation, so that packing is not easy to extrude unevenly, and water leakage of the valve rod is caused.

3) The sealing mode is changed into a multi-channel sealing mode consisting of two O-shaped rings and flexible graphite packing to replace the original flexible packing sealing mode, and the sealing effect can be effectively improved.

4) The packing sealing device for the large butterfly valve can eliminate the leakage problem between the valve body and the packing chamber by 100 percent, prolong the service life of the valve, ensure the supply of circulating cooling water and ensure the stable operation of a unit.

Drawings

FIG. 1 is a schematic side sectional view of a packing chamber of an embodiment of the apparatus of the present invention;

FIG. 2 is a schematic top view of the packing chamber of the apparatus of the present invention in an embodiment;

FIG. 3 is a schematic side sectional view of a packing gland of the apparatus of the present invention in an embodiment;

FIG. 4 is a schematic top view of a packing gland of the apparatus of the present invention in an embodiment;

the reference numbers in the figures indicate:

1. first filler cavity, 2, second filler cavity, 3, oblique angle, 4, first bolt hole, 5, O type ring groove, 6, gland, 7, discoid base, 8, cylinder, 9, central through hole, 10, second bolt hole, 11, cyclic annular installation casing.

Detailed Description

The utility model is described in detail below with reference to the figures and specific embodiments. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.

Examples

The utility model relates to a packing sealing device for a large butterfly valve, which comprises an improved multi-step multi-form packing chamber arranged at the upper end part of a valve body of the butterfly valve and an improved packing gland arranged with the packing chamber, wherein the packing gland is a gland provided with four-point fixed points. The device carries out rationalization to gland and the packing cavity in the butterfly valve and improves: the locking form of the new packing gland is changed into 4-point fixation, the adverse effect caused by uneven stress when the bolt is fastened is avoided, and the sealing form is changed into multi-sealing formed by 2O-shaped rings and flexible graphite packing to replace the original flexible packing sealing.

Specifically, an improved multi-step and multi-form packing chamber is shown in fig. 1-2, and comprises an annular mounting shell 11 and a first packing chamber 1 and a second packing chamber 2 which are arranged in the annular mounting shell 11 and communicated with each other, wherein the first packing chamber 1 and the second packing chamber 2 are arranged at the central position of the annular mounting shell 11. The outer surface of the periphery of the annular mounting shell 11 is in a cross structure and is provided with four first bolt holes 4.

The diameter of the first packing chamber 1 is larger than the diameter of the second packing chamber 2. The connection part of the first packing chamber 1 and the second packing chamber 2 is provided with a 15-degree bevel 3 for adding a 6mm O-shaped ring sleeve as the first seal from the valve rod to the packing chamber.

The second packing chamber 2 is provided with a flexible packing, which can be preferably a flexible graphite packing, for serving as a second seal of the valve. An O-shaped ring groove 5 is arranged at the joint surface of the annular mounting shell 11 corresponding to the second packing chamber 2 and the valve body and used for mounting an O-shaped sealing ring as the last sealing.

In this embodiment, the O-ring groove 5 is an O-ring groove with a width of 6mm and a depth of 3mm, and is used for installing a 5mm O-ring.

The packing gland 6 is intended to be fitted with the second packing chamber 2. The dimensions of the second packing chamber 2 match the dimensions of the packing gland 6. As shown in fig. 3 and 4, the packing gland 6 includes a disk-shaped base 7, a cylinder 8 is provided on the disk-shaped base 7, a central through hole 9 is provided at the center of the cylinder 8, and the central through hole 9 is provided to penetrate through the disk-shaped base 7. The disc-shaped base 7 is provided with four second bolt holes 10 in a cross structure. The set position and size of the second bolt hole 10 are matched with those of the first bolt hole 4, and the second bolt hole and the first bolt hole are used for fixing the packing gland 6 and the packing chamber through fastening bolts.

The improved packing chamber has proper O-ring inside, and this can reduce the leakage greatly. In addition, the packing chamber is changed into multi-stage multi-form sealing, and the packing gland locking form adopts four-point fixation, so that the packing is not easy to extrude unevenly, and the water leakage of the valve rod is caused. According to the design, the leakage of the packing chamber can be eliminated by 100 percent, and the workload of daily maintenance personnel is reduced. And the service life of the valve can be prolonged, the supply of circulating cooling water is ensured, and the stable operation of the unit is ensured.

While the utility model has been described with reference to specific embodiments, the utility model is not limited thereto, and those skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope of the utility model. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The packing sealing device for the large butterfly valve comprises a packing chamber arranged at the upper end part of a valve body of the butterfly valve and a packing gland (6) assembled with the packing chamber, and is characterized in that the packing chamber comprises an annular mounting shell (11), and a first packing chamber (1) and a second packing chamber (2) which are arranged in the annular mounting shell (11) and are communicated with each other, wherein the first packing chamber (1) and the second packing chamber (2) are arranged at the central position of the annular mounting shell (11), the diameter of the first packing chamber (1) is larger than that of the second packing chamber (2), and the second packing chamber (2) is assembled and connected with the packing gland (6).

2. The stuffing seal for large butterfly valves according to claim 1, characterized in that the connection of the first stuffing chamber (1) and the second stuffing chamber (2) is provided with a bevel (3) to mount an O-ring trap.

3. The packing seal device for a large butterfly valve according to claim 1, wherein an O-ring groove (5) for mounting an O-ring is formed at a joint surface of the annular mounting housing (11) and the valve body corresponding to the second packing chamber (2).

4. The packing seal device for a large butterfly valve according to claim 1, characterized in that the annular mounting housing (11) is provided with a mounting means for fitting connection with the packing gland (6).

5. The stuffing seal for large butterfly valves according to claim 4, wherein said mounting means comprises four first bolt holes (4) in a cross configuration provided on the peripheral outer surface of said annular mounting housing (11).

6. The packing seal device for a large butterfly valve according to claim 5, wherein the packing gland (6) comprises a disk-shaped base (7) and a cylinder (8) arranged on the disk-shaped base (7), a central through hole (9) is arranged in the center of the cylinder (8), the central through hole (9) is arranged through the disk-shaped base (7), four second bolt holes (10) are arranged in a cross structure on the upper surface of the disk-shaped base (7), and the set positions and sizes of the second bolt holes (10) are matched with the set positions and sizes of the first bolt holes (4).

7. A stuffing seal for large butterfly valves according to claim 2, characterized in that said bevel (3) is a bevel of 15 °.

8. The stuffing seal for large butterfly valves according to claim 3, characterized in that the O-ring groove (5) has a width of 6mm and a depth of 3 mm.

9. A stuffing seal for large butterfly valves according to claim 1, characterized in that inside said second stuffing chamber (2) there is a flexible stuffing.

10. A packing seal for large butterfly valves according to claim 9, characterised in that a flexible graphite packing is provided in the second packing chamber (2).