JPH07139644A - High temperature slide valve - Google Patents

Abstract

(57) [Summary] [Structure] The packing box 21 is formed in a cylindrical shape with a bottom, and an inner packing portion 23, a central packing portion 24, and an outer packing portion 25 are arranged inside the packing box 21. An elastic biasing means 26 is interposed between the inner packing portion 23 and the central packing portion 24, and a locking mechanism portion 26 is interposed between the central packing portion 24 and the outer packing portion 25. The packing land 33 is arranged in the opening 21 b of the packing box 21, and the fastening means 34 is interposed between the packing land 33 and the packing box 21. [Effect] By pressing the inner packing portion and the outer packing portion by the elastic biasing means, the sealing property can be maintained for a long period of time, and the frequency of tightening by the tightening means can be suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high temperature slide valve used in petroleum refining equipment and the like.

[0002]

2. Description of the Related Art FIG. 2 is a partially cutaway perspective view of a conventional high temperature slide valve. In FIG. 2, the valve housing 1 of the high temperature slide valve has a cylindrical flow passage 2, and the flow passage 2 is a valve seat 3
And is configured to open and close the fluid flow by sliding the valve body 4. A bonnet 5 is formed so as to project from a side portion of the valve box 1, and an opening portion thereof is closed by a bonnet cover 6. A packing box 7 projects horizontally from the center of the bonnet cover 6. The valve rod 9 passes through the bonnet 5,
It is inserted through the shaft hole of the packing box 7. A plurality of gland packings 10A are fitted in the packing box 7,
It is sealed by these gland packings 10A. The gland packing 10A is held by the packing land 11. Further, an aeration pipe 12 is attached to the packing box 7 in order to prevent foreign matter from entering the gland portion 10, and air is blown in to perform purging. A back sheet 13 is attached to the bonnet cover 6.

[0003]

However, although the seal of the valve rod 9 of the conventional high temperature slide valve is purged by air from the aeration pipe 12, foreign matter such as dust enters the gland portion 10. There is a risk. Further, in the conventional high temperature slide valve, there is a problem that the life of the gland portion is short and the valve rod 9 is worn by the purge by air or steam. Further, when the gland packing 10A is worn, the gland bolt attaching the packing land 11 is retightened, and the gland packing 10A is pressed by the packing land 11 in the axial direction of the valve rod 9 so that Gland packing 1 for the inner peripheral surface of the shaft hole of the packing box 7
Although the pressure contact force of 0 A is increased, there is a problem that the pressing force against the packing land 11 does not reach the gland packing 10A on the bonnet cover 13 side.

The present invention solves the above-mentioned problems, and can perform reliable sealing without using a purge gas, and can prevent erosion of a valve rod by not using a purge gas. It is an object of the present invention to provide a high temperature slide valve capable of maintaining a sealing function of packing for a long time.

[0005]

In order to solve the above-mentioned problems, a high temperature slide valve of the present invention holds a valve rod connected to a valve element in a packing box so that the valve rod can be withdrawn and withdrawn in the axial direction. In the high temperature slide valve in which the valve body slides in the valve box by opening and closing to open and close the flow path in the valve box with the valve body,
The packing box is formed in the shape of a cylinder with a bottom, and a shaft hole is formed in the bottom of the packing box located inside the valve box facing the valve body, and the valve rod is placed through this shaft hole. Inside the box, the inner packing part, the center packing part, and the outer packing part are arranged in order from the bottom side, and both packing parts are set upside down along the axial direction of the valve rod between the inner packing part and the center packing part. An elastic urging means for pressing in the direction is interposed, and a locking mechanism that receives the central packing in the axial direction of the valve rod is interposed between the central packing and the outer packing, and this locking mechanism is It is formed so as to be movable toward the center packing part along the axial direction of the valve stem, and packing lands are arranged in the opening of the packing box, and the packing lands are pressed between the packing lands and packing boxes toward the outer packing. Intervening tightening means Those were.

In addition, an injection port ring that forms a sealant filling space is provided in the central packing portion, and a sealant filling port that communicates with the sealant filling space is provided in the packing box.

[0007]

With the above structure, the inner packing portion, the central packing portion, and the outer packing portion are slidably in contact with the valve rod on the inner peripheral surface, and are pressed against the inner side surface of the packing box on the outer peripheral surface to contact the outer peripheral surface of the valve rod and the packing box. Seal between the inner surfaces of the. At this time, the elastic urging means presses the inner packing part and the central packing part in the direction opposite to each other along the axial direction of the valve rod, and is received by the inner packing part and the locking mechanism part which are received by the bottom part of the packing box. The central packing portion receives the pressing force of the elastic biasing means and tries to expand in the radial direction of the valve rod. Therefore, even if the inner packing portion and the outer packing portion are worn, the sealing performance is not impaired for a long period of time.

Each packing part wears due to long-term use, the sealability of the inner packing part and the central packing part is impaired even with the pressing force of the elastic biasing means, and the controlled fluid leaks also to the outer packing part. In this case, the sealing force is increased by increasing the pressing force of the tightening means and pressing the outer packing part in the axial direction of the valve stem through the packing land to expand the outer packing part in the radial direction of the valve stem. Recover. At this time, the pressing force of the tightening means acts on the central packing portion via the outer packing portion and the locking mechanism portion, and by force acts on the inner packing portion via the elastic biasing means. The sealing property of the internal packing part is improved.

If the sealing property of the outer packing part is not restored even if the pressing force of the tightening means is increased, the outer packing part is replaced while the controlled fluid is flowing. For this reason, the sealant is filled from the sealant filling port into the sealant filling space, and the external packing is replaced in a state where the filled sealant ensures the sealing property.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Members having the same functions as those described with reference to FIG. 2 are designated by the same reference numerals and the description thereof will be omitted. In FIG. 1, the inner surface of the bonnet cover 6 is covered with a refractory material 6a, and the bonnet cover 6 is fixed to the packing box 2
1 is provided. The packing box 21 has a bottomed cylindrical shape, and a shaft hole 22 is formed in a bottom portion 21a of the packing box 21 located inside the valve box A facing the valve body. The valve rod 9 is inserted into the shaft hole 22 so as to be retractable in the axial direction.

Inside the packing box 21, the inner packing portion 23 and the central packing portion 24 are sequentially arranged from the bottom 21a side.
And the outer packing portion 25 are arranged. Each packing part 2
3, 24, and 25 are gland packings that are slidably contacted with the valve rod 9 on the inner peripheral surface and the packing box 2 on the outer peripheral surface.
Press the inner surface of 1. Packing portions 23, 24, 25
May be expanded graphite compression-molded, such as Grafoil.

Inner packing portion 23 and central packing portion 24
In between, an elastic biasing means 26 for pressing both packing parts 23, 24 in a direction opposite to the axial direction of the valve rod 9 is provided.
Is intervening. The elastic biasing means 26 includes a backup ring 27 and a guide ring 28 that are movably provided in the axial direction of the valve rod 9, and a spring 29 interposed between the backup ring 27 and the guide ring 28. The spring 29 is located outside the small diameter portion 28 a of the guide ring 28 and has one end, and one end of the spring 29 has a large diameter portion 28 b of the guide ring 28.
, And the other end is in contact with the backup ring 27.

Central packing portion 24 and outer packing portion 25
A locking mechanism portion 30 that receives the central packing portion 24 in the axial direction of the valve rod is interposed between the locking mechanism portion 30 and the central packing portion 30 along the axial direction of the valve rod 9. The locking ring 31 is provided so as to be movable toward the portion 24, and the locking pin 32 is engaged with the locking ring 31. The locking ring 31 has a large diameter portion 31 a on one side facing the central packing portion 24 and a small diameter portion 31 b on the other side facing the outer packing portion 25. The locking pin 32 is arranged after penetrating the wall of the packing box 21 in the radial direction of the valve rod 9,
It is fixed to the packing box 21 by welding, and one end thereof is in contact with the large diameter portion 31a of the locking ring 31 in the axial direction of the valve rod 9. Therefore, the locking ring 31 cannot move toward the outer packing portion 25.

A packing land 33 is arranged in the opening 21b of the packing box 21.
Is composed of a pressing portion 33a that contacts the outer packing portion 25 and a flange portion 33b. Tightening means 34 is interposed between the flange portion 33 b of the packing land 33 and the packing box 21. This tightening means 34 is provided with a packing land 33.
Of the tightening bolt 34a that is screwed into the packing box 21 by inserting the through hole 33c formed in the flange portion 33b, the tightening nut 34b that is screwed into the tightening bolt 34a, and the tightening nut 34a and the flange portion 33b. It is composed of a plurality of disc springs 34c interposed therebetween, and the packing land 33 is always pressed against the outer packing portion 25 via the flange portion 33b by the urging force of the disc spring 34c, and the tightening nut 34b is also provided.
The pressing force is adjusted by tightening.

The central packing portion 24 has a first inlet port ring 35 at an intermediate position, and the first inlet port ring 35 forms a sealant filling space 36, and an outer space 36.
a and the inner space 36b are separated from each other by the walls 36a, 36
It has a through hole 36c communicating with b. Packing box 2
1 is provided with a sealant filling port 37 communicating with the sealant filling space 36, and this sealant filling port 37 is for supplying an emergency sealant 38 such as steam or grease to the sealant filling space 36.

The outer packing portion 25 has a second injection ring 39 at an intermediate position, and the second injection port ring 39 forms a grease filling space 40. The outer space 40a and the inner space 40b are separated from each other by a wall body. Has a through hole 40c that connects the two spaces 40a and 40b. The packing box 21 is provided with a grease filling port 41 communicating with the grease filling space 40, and the grease filling port 41 is for supplying the grease 42 to the grease filling space 40.

The operation of the above structure will be described below.
The inner packing portion 23, the central packing portion 24, and the outer packing portion 25 slidably contact the valve rod 9 on the inner peripheral surface and press contact with the inner side surface of the packing box 21 on the outer peripheral surface to form the outer peripheral surface of the valve rod 9 and the packing box 21. Seal between the inner surfaces.

At this time, the spring 29 of the elastic biasing means 26 causes the backup ring 27 and the guide ring 28 to move.
Through the inner packing portion 23 and the central packing portion 24
Is pressed in the opposite direction along the axial direction of the valve rod 9.
That is, the elastic biasing means 26 presses the inner packing portion 23 toward the bottom portion 21a, and the central packing portion 24
Is pressed toward the locking mechanism section 30.

The inner packing portion 23 received by the bottom portion 21a of the packing box 21 and the central packing portion 24 received by the locking ring 31 of the locking mechanism portion 30 receive the pressing force of the elastic biasing means 26 and the valve rod. In order to expand in the radial direction of 9, the outer peripheral surface of the valve rod 9 and the inner surface of the packing box 21 are pressed against each other. Therefore, even if the inner packing portion 23 and the outer packing portion 24 are worn due to friction with the valve rod 9, the sealability can be maintained for a long period of time. Also, from the grease filling port 41 to the external packing 2
The grease 42 is greased in the grease filling space 40 of No. 5 to extend the life of the outer packing portion 25.

Each packing portion 23, 2 is used for a long period of time.
4 and 25 are worn, the sealability of the inner packing portion 23 and the central packing portion 24 is impaired even with the pressing force of the elastic biasing means 26, and the disc spring 34c of the tightening means 34 is damaged.
If the sealing property of the outer packing part 25 is impaired even if the pressing force is applied and the controlled fluid leaks, the tightening nut 34b of the tightening means 34 is retightened to restore the sealing property.

That is, the tightening force of the tightening nut 34b acts on the flange portion 33b of the packing land 33 via the disc spring 34c, and the pressing portion 33a of the packing land 33 causes the outer packing portion 25 to move to the axial center of the valve rod 9. The outer packing part 25 is expanded in the radial direction of the valve rod 9 by pressing in the direction to restore the sealing property.

At this time, in the locking mechanism portion 30, the locking ring 31 that engages with the locking pin 32 has the central packing portion 2.
You can move to side 4. Therefore, the pressing force of the tightening means 34 acts on the central packing portion 24 via the outer packing portion 25 and the locking ring 31 of the locking mechanism portion 30, and by force, the inner packing via the elastic biasing means 26. Since it acts on the portion 23, the sealability of the central packing portion 24 and the inner packing portion 23 is also improved.

If the sealing property of the outer packing portion 25 is not restored even if the pressing force of the tightening means 34 is increased by the additional tightening of the tightening nut 34b, the outer packing portion 25 is replaced while the controlled fluid is flowing. There is a need to. Therefore, the emergency sealant 3 such as steam or grease is introduced from the sealant filling port 37 to the sealant filling space 36.
8 filled and filled emergency sealant 38
The outer packing 25
Replace.

[0024]

As described above, according to the present invention, the inner packing portion and the central packing portion try to expand in the radial direction of the valve rod by receiving the pressing force of the elastic biasing means. Even if the outer packing part is worn, the sealing property can be maintained for a long period of time, and the frequency of additional tightening in the tightening means can be suppressed. By ensuring the sealability by the sealant filled in the sealant filling space, the outer packing part can be replaced while the controlled fluid flows in the valve box. Moreover, the conventional purge gas is unnecessary, and the erosion of the valve rod can be prevented by not using the purge gas.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a high temperature slide valve according to an embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view of a conventional high temperature slide valve.

[Explanation of symbols]

 21 packing box 23 inner packing part 24 central packing part 25 outer packing part 26 elastic biasing means 30 locking mechanism part 33 packing land 34 tightening means

Claims (2)

[Claims] 1. A valve rod connected to a valve body is retained in a packing box so as to be able to move back and forth in the axial direction, and the valve body slides in the valve box when the valve rod moves back and forth, so that the flow path in the valve box is valved. In a high temperature slide valve that opens and closes with the body, the packing box is formed in a cylindrical shape with a bottom, and a shaft hole is formed at the bottom of the packing box located inside the valve box facing the valve body. Insert the valve stem into the packing box, place the inner packing part, the center packing part, and the outer packing part in order from the bottom side inside the packing box, and insert both packing parts between the inner packing part and the center packing part. An elastic biasing means that presses the rod in the direction opposite to the axial direction is interposed, and a locking mechanism that receives the central packing in the axial direction of the valve rod is provided between the central packing and the outer packing. And install this locking mechanism along the axial direction of the valve stem. The packing land is arranged so as to be movable toward the central packing part, the packing land is arranged in the opening of the packing box, and the tightening means for pressing the packing land toward the outer packing is interposed between the packing land and the packing box. A high temperature slide valve characterized in that 2. The high temperature use machine according to claim 1, wherein the central packing part is provided with an inlet ring forming a sealant filling space, and the packing box is provided with a sealant filling port communicating with the sealant filling space. Slide valve.